includes/libs/lessc.inc.php

   1 <?php
   2 // @codingStandardsIgnoreFile File external to MediaWiki. Ignore coding conventions checks.
   3 /**
   4  * lessphp v0.4.0@2cc77e3c7b
   5  * http://leafo.net/lessphp
   6  *
   7  * LESS CSS compiler, adapted from http://lesscss.org
   8  *
   9  * For ease of distribution, lessphp 0.4.0 is under a dual license.
  10  * You are free to pick which one suits your needs.
  11  *
  12  * MIT LICENSE
  13  *
  14  * Copyright 2013, Leaf Corcoran <leafot@gmail.com>
  15  *
  16  * Permission is hereby granted, free of charge, to any person obtaining
  17  * a copy of this software and associated documentation files (the
  18  * "Software"), to deal in the Software without restriction, including
  19  * without limitation the rights to use, copy, modify, merge, publish,
  20  * distribute, sublicense, and/or sell copies of the Software, and to
  21  * permit persons to whom the Software is furnished to do so, subject to
  22  * the following conditions:
  23  *
  24  * The above copyright notice and this permission notice shall be
  25  * included in all copies or substantial portions of the Software.
  26  *
  27  * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,
  28  * EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
  29  * MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND
  30  * NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE
  31  * LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION
  32  * OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION
  33  * WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
  34  *
  35  * GPL VERSION 3
  36  *
  37  * Please refer to http://www.gnu.org/licenses/gpl-3.0.html for the full
  38  * text of the GPL version 3
  39  */
  40
  41
  42 /**
  43  * The LESS compiler and parser.
  44  *
  45  * Converting LESS to CSS is a three stage process. The incoming file is parsed
  46  * by `lessc_parser` into a syntax tree, then it is compiled into another tree
  47  * representing the CSS structure by `lessc`. The CSS tree is fed into a
  48  * formatter, like `lessc_formatter` which then outputs CSS as a string.
  49  *
  50  * During the first compile, all values are *reduced*, which means that their
  51  * types are brought to the lowest form before being dump as strings. This
  52  * handles math equations, variable dereferences, and the like.
  53  *
  54  * The `parse` function of `lessc` is the entry point.
  55  *
  56  * In summary:
  57  *
  58  * The `lessc` class creates an instance of the parser, feeds it LESS code,
  59  * then transforms the resulting tree to a CSS tree. This class also holds the
  60  * evaluation context, such as all available mixins and variables at any given
  61  * time.
  62  *
  63  * The `lessc_parser` class is only concerned with parsing its input.
  64  *
  65  * The `lessc_formatter` takes a CSS tree, and dumps it to a formatted string,
  66  * handling things like indentation.
  67  */
  68 class lessc {
  69         static public $VERSION = "v0.4.0";
  70
  71         static public $TRUE = array("keyword", "true");
  72         static public $FALSE = array("keyword", "false");
  73
  74         protected $libFunctions = array();
  75         protected $registeredVars = array();
  76         protected $preserveComments = false;
  77
  78         public $vPrefix = '@'; // prefix of abstract properties
  79         public $mPrefix = '$'; // prefix of abstract blocks
  80         public $parentSelector = '&';
  81
  82         public $importDisabled = false;
  83         public $importDir = '';
  84
  85         protected $numberPrecision = null;
  86
  87         protected $allParsedFiles = array();
  88
  89         // set to the parser that generated the current line when compiling
  90         // so we know how to create error messages
  91         protected $sourceParser = null;
  92         protected $sourceLoc = null;
  93
  94         static protected $nextImportId = 0; // uniquely identify imports
  95
  96         // attempts to find the path of an import url, returns null for css files
  97         protected function findImport($url) {
  98                 foreach ((array)$this->importDir as $dir) {
  99                         $full = $dir.(substr($dir, -1) != '/' ? '/' : '').$url;
 100                         if ($this->fileExists($file = $full.'.less') || $this->fileExists($file = $full)) {
 101                                 return $file;
 102                         }
 103                 }
 104
 105                 return null;
 106         }
 107
 108         protected function fileExists($name) {
 109                 return is_file($name);
 110         }
 111
 112         static public function compressList($items, $delim) {
 113                 if (!isset($items[1]) && isset($items[0])) return $items[0];
 114                 else return array('list', $delim, $items);
 115         }
 116
 117         static public function preg_quote($what) {
 118                 return preg_quote($what, '/');
 119         }
 120
 121         protected function tryImport($importPath, $parentBlock, $out) {
 122                 if ($importPath[0] == "function" && $importPath[1] == "url") {
 123                         $importPath = $this->flattenList($importPath[2]);
 124                 }
 125
 126                 $str = $this->coerceString($importPath);
 127                 if ($str === null) return false;
 128
 129                 $url = $this->compileValue($this->lib_e($str));
 130
 131                 // don't import if it ends in css
 132                 if (substr_compare($url, '.css', -4, 4) === 0) return false;
 133
 134                 $realPath = $this->findImport($url);
 135
 136                 if ($realPath === null) return false;
 137
 138                 if ($this->importDisabled) {
 139                         return array(false, "/* import disabled */");
 140                 }
 141
 142                 if (isset($this->allParsedFiles[realpath($realPath)])) {
 143                         return array(false, null);
 144                 }
 145
 146                 $this->addParsedFile($realPath);
 147                 $parser = $this->makeParser($realPath);
 148                 $root = $parser->parse(file_get_contents($realPath));
 149
 150                 // set the parents of all the block props
 151                 foreach ($root->props as $prop) {
 152                         if ($prop[0] == "block") {
 153                                 $prop[1]->parent = $parentBlock;
 154                         }
 155                 }
 156
 157                 // copy mixins into scope, set their parents
 158                 // bring blocks from import into current block
 159                 // TODO: need to mark the source parser these came from this file
 160                 foreach ($root->children as $childName => $child) {
 161                         if (isset($parentBlock->children[$childName])) {
 162                                 $parentBlock->children[$childName] = array_merge(
 163                                         $parentBlock->children[$childName],
 164                                         $child);
 165                         } else {
 166                                 $parentBlock->children[$childName] = $child;
 167                         }
 168                 }
 169
 170                 $pi = pathinfo($realPath);
 171                 $dir = $pi["dirname"];
 172
 173                 list($top, $bottom) = $this->sortProps($root->props, true);
 174                 $this->compileImportedProps($top, $parentBlock, $out, $parser, $dir);
 175
 176                 return array(true, $bottom, $parser, $dir);
 177         }
 178
 179         protected function compileImportedProps($props, $block, $out, $sourceParser, $importDir) {
 180                 $oldSourceParser = $this->sourceParser;
 181
 182                 $oldImport = $this->importDir;
 183
 184                 // TODO: this is because the importDir api is stupid
 185                 $this->importDir = (array)$this->importDir;
 186                 array_unshift($this->importDir, $importDir);
 187
 188                 foreach ($props as $prop) {
 189                         $this->compileProp($prop, $block, $out);
 190                 }
 191
 192                 $this->importDir = $oldImport;
 193                 $this->sourceParser = $oldSourceParser;
 194         }
 195
 196         /**
 197          * Recursively compiles a block.
 198          *
 199          * A block is analogous to a CSS block in most cases. A single LESS document
 200          * is encapsulated in a block when parsed, but it does not have parent tags
 201          * so all of it's children appear on the root level when compiled.
 202          *
 203          * Blocks are made up of props and children.
 204          *
 205          * Props are property instructions, array tuples which describe an action
 206          * to be taken, eg. write a property, set a variable, mixin a block.
 207          *
 208          * The children of a block are just all the blocks that are defined within.
 209          * This is used to look up mixins when performing a mixin.
 210          *
 211          * Compiling the block involves pushing a fresh environment on the stack,
 212          * and iterating through the props, compiling each one.
 213          *
 214          * See lessc::compileProp()
 215          *
 216          */
 217         protected function compileBlock($block) {
 218                 switch ($block->type) {
 219                 case "root":
 220                         $this->compileRoot($block);
 221                         break;
 222                 case null:
 223                         $this->compileCSSBlock($block);
 224                         break;
 225                 case "media":
 226                         $this->compileMedia($block);
 227                         break;
 228                 case "directive":
 229                         $name = "@" . $block->name;
 230                         if (!empty($block->value)) {
 231                                 $name .= " " . $this->compileValue($this->reduce($block->value));
 232                         }
 233
 234                         $this->compileNestedBlock($block, array($name));
 235                         break;
 236                 default:
 237                         $this->throwError("unknown block type: $block->type\n");
 238                 }
 239         }
 240
 241         protected function compileCSSBlock($block) {
 242                 $env = $this->pushEnv();
 243
 244                 $selectors = $this->compileSelectors($block->tags);
 245                 $env->selectors = $this->multiplySelectors($selectors);
 246                 $out = $this->makeOutputBlock(null, $env->selectors);
 247
 248                 $this->scope->children[] = $out;
 249                 $this->compileProps($block, $out);
 250
 251                 $block->scope = $env; // mixins carry scope with them!
 252                 $this->popEnv();
 253         }
 254
 255         protected function compileMedia($media) {
 256                 $env = $this->pushEnv($media);
 257                 $parentScope = $this->mediaParent($this->scope);
 258
 259                 $query = $this->compileMediaQuery($this->multiplyMedia($env));
 260
 261                 $this->scope = $this->makeOutputBlock($media->type, array($query));
 262                 $parentScope->children[] = $this->scope;
 263
 264                 $this->compileProps($media, $this->scope);
 265
 266                 if (count($this->scope->lines) > 0) {
 267                         $orphanSelelectors = $this->findClosestSelectors();
 268                         if (!is_null($orphanSelelectors)) {
 269                                 $orphan = $this->makeOutputBlock(null, $orphanSelelectors);
 270                                 $orphan->lines = $this->scope->lines;
 271                                 array_unshift($this->scope->children, $orphan);
 272                                 $this->scope->lines = array();
 273                         }
 274                 }
 275
 276                 $this->scope = $this->scope->parent;
 277                 $this->popEnv();
 278         }
 279
 280         protected function mediaParent($scope) {
 281                 while (!empty($scope->parent)) {
 282                         if (!empty($scope->type) && $scope->type != "media") {
 283                                 break;
 284                         }
 285                         $scope = $scope->parent;
 286                 }
 287
 288                 return $scope;
 289         }
 290
 291         protected function compileNestedBlock($block, $selectors) {
 292                 $this->pushEnv($block);
 293                 $this->scope = $this->makeOutputBlock($block->type, $selectors);
 294                 $this->scope->parent->children[] = $this->scope;
 295
 296                 $this->compileProps($block, $this->scope);
 297
 298                 $this->scope = $this->scope->parent;
 299                 $this->popEnv();
 300         }
 301
 302         protected function compileRoot($root) {
 303                 $this->pushEnv();
 304                 $this->scope = $this->makeOutputBlock($root->type);
 305                 $this->compileProps($root, $this->scope);
 306                 $this->popEnv();
 307         }
 308
 309         protected function compileProps($block, $out) {
 310                 foreach ($this->sortProps($block->props) as $prop) {
 311                         $this->compileProp($prop, $block, $out);
 312                 }
 313                 $out->lines = $this->deduplicate($out->lines);
 314         }
 315
 316         /**
 317          * Deduplicate lines in a block. Comments are not deduplicated. If a
 318          * duplicate rule is detected, the comments immediately preceding each
 319          * occurence are consolidated.
 320          */
 321         protected function deduplicate($lines) {
 322                 $unique = array();
 323                 $comments = array();
 324
 325                 foreach($lines as $line) {
 326                         if (strpos($line, '/*') === 0) {
 327                                 $comments[] = $line;
 328                                 continue;
 329                         }
 330                         if (!in_array($line, $unique)) {
 331                                 $unique[] = $line;
 332                         }
 333                         array_splice($unique, array_search($line, $unique), 0, $comments);
 334                         $comments = array();
 335                 }
 336                 return array_merge($unique, $comments);
 337         }
 338
 339         protected function sortProps($props, $split = false) {
 340                 $vars = array();
 341                 $imports = array();
 342                 $other = array();
 343                 $stack = array();
 344
 345                 foreach ($props as $prop) {
 346                         switch ($prop[0]) {
 347                         case "comment":
 348                                 $stack[] = $prop;
 349                                 break;
 350                         case "assign":
 351                                 $stack[] = $prop;
 352                                 if (isset($prop[1][0]) && $prop[1][0] == $this->vPrefix) {
 353                                         $vars = array_merge($vars, $stack);
 354                                 } else {
 355                                         $other = array_merge($other, $stack);
 356                                 }
 357                                 $stack = array();
 358                                 break;
 359                         case "import":
 360                                 $id = self::$nextImportId++;
 361                                 $prop[] = $id;
 362                                 $stack[] = $prop;
 363                                 $imports = array_merge($imports, $stack);
 364                                 $other[] = array("import_mixin", $id);
 365                                 $stack = array();
 366                                 break;
 367                         default:
 368                                 $stack[] = $prop;
 369                                 $other = array_merge($other, $stack);
 370                                 $stack = array();
 371                                 break;
 372                         }
 373                 }
 374                 $other = array_merge($other, $stack);
 375
 376                 if ($split) {
 377                         return array(array_merge($vars, $imports), $other);
 378                 } else {
 379                         return array_merge($vars, $imports, $other);
 380                 }
 381         }
 382
 383         protected function compileMediaQuery($queries) {
 384                 $compiledQueries = array();
 385                 foreach ($queries as $query) {
 386                         $parts = array();
 387                         foreach ($query as $q) {
 388                                 switch ($q[0]) {
 389                                 case "mediaType":
 390                                         $parts[] = implode(" ", array_slice($q, 1));
 391                                         break;
 392                                 case "mediaExp":
 393                                         if (isset($q[2])) {
 394                                                 $parts[] = "($q[1]: " .
 395                                                         $this->compileValue($this->reduce($q[2])) . ")";
 396                                         } else {
 397                                                 $parts[] = "($q[1])";
 398                                         }
 399                                         break;
 400                                 case "variable":
 401                                         $parts[] = $this->compileValue($this->reduce($q));
 402                                 break;
 403                                 }
 404                         }
 405
 406                         if (count($parts) > 0) {
 407                                 $compiledQueries[] =  implode(" and ", $parts);
 408                         }
 409                 }
 410
 411                 $out = "@media";
 412                 if (!empty($parts)) {
 413                         $out .= " " .
 414                                 implode($this->formatter->selectorSeparator, $compiledQueries);
 415                 }
 416                 return $out;
 417         }
 418
 419         protected function multiplyMedia($env, $childQueries = null) {
 420                 if (is_null($env) ||
 421                         !empty($env->block->type) && $env->block->type != "media")
 422                 {
 423                         return $childQueries;
 424                 }
 425
 426                 // plain old block, skip
 427                 if (empty($env->block->type)) {
 428                         return $this->multiplyMedia($env->parent, $childQueries);
 429                 }
 430
 431                 $out = array();
 432                 $queries = $env->block->queries;
 433                 if (is_null($childQueries)) {
 434                         $out = $queries;
 435                 } else {
 436                         foreach ($queries as $parent) {
 437                                 foreach ($childQueries as $child) {
 438                                         $out[] = array_merge($parent, $child);
 439                                 }
 440                         }
 441                 }
 442
 443                 return $this->multiplyMedia($env->parent, $out);
 444         }
 445
 446         protected function expandParentSelectors(&$tag, $replace) {
 447                 $parts = explode("$&$", $tag);
 448                 $count = 0;
 449                 foreach ($parts as &$part) {
 450                         $part = str_replace($this->parentSelector, $replace, $part, $c);
 451                         $count += $c;
 452                 }
 453                 $tag = implode($this->parentSelector, $parts);
 454                 return $count;
 455         }
 456
 457         protected function findClosestSelectors() {
 458                 $env = $this->env;
 459                 $selectors = null;
 460                 while ($env !== null) {
 461                         if (isset($env->selectors)) {
 462                                 $selectors = $env->selectors;
 463                                 break;
 464                         }
 465                         $env = $env->parent;
 466                 }
 467
 468                 return $selectors;
 469         }
 470
 471
 472         // multiply $selectors against the nearest selectors in env
 473         protected function multiplySelectors($selectors) {
 474                 // find parent selectors
 475
 476                 $parentSelectors = $this->findClosestSelectors();
 477                 if (is_null($parentSelectors)) {
 478                         // kill parent reference in top level selector
 479                         foreach ($selectors as &$s) {
 480                                 $this->expandParentSelectors($s, "");
 481                         }
 482
 483                         return $selectors;
 484                 }
 485
 486                 $out = array();
 487                 foreach ($parentSelectors as $parent) {
 488                         foreach ($selectors as $child) {
 489                                 $count = $this->expandParentSelectors($child, $parent);
 490
 491                                 // don't prepend the parent tag if & was used
 492                                 if ($count > 0) {
 493                                         $out[] = trim($child);
 494                                 } else {
 495                                         $out[] = trim($parent . ' ' . $child);
 496                                 }
 497                         }
 498                 }
 499
 500                 return $out;
 501         }
 502
 503         // reduces selector expressions
 504         protected function compileSelectors($selectors) {
 505                 $out = array();
 506
 507                 foreach ($selectors as $s) {
 508                         if (is_array($s)) {
 509                                 list(, $value) = $s;
 510                                 $out[] = trim($this->compileValue($this->reduce($value)));
 511                         } else {
 512                                 $out[] = $s;
 513                         }
 514                 }
 515
 516                 return $out;
 517         }
 518
 519         protected function eq($left, $right) {
 520                 return $left == $right;
 521         }
 522
 523         protected function patternMatch($block, $orderedArgs, $keywordArgs) {
 524                 // match the guards if it has them
 525                 // any one of the groups must have all its guards pass for a match
 526                 if (!empty($block->guards)) {
 527                         $groupPassed = false;
 528                         foreach ($block->guards as $guardGroup) {
 529                                 foreach ($guardGroup as $guard) {
 530                                         $this->pushEnv();
 531                                         $this->zipSetArgs($block->args, $orderedArgs, $keywordArgs);
 532
 533                                         $negate = false;
 534                                         if ($guard[0] == "negate") {
 535                                                 $guard = $guard[1];
 536                                                 $negate = true;
 537                                         }
 538
 539                                         $passed = $this->reduce($guard) == self::$TRUE;
 540                                         if ($negate) $passed = !$passed;
 541
 542                                         $this->popEnv();
 543
 544                                         if ($passed) {
 545                                                 $groupPassed = true;
 546                                         } else {
 547                                                 $groupPassed = false;
 548                                                 break;
 549                                         }
 550                                 }
 551
 552                                 if ($groupPassed) break;
 553                         }
 554
 555                         if (!$groupPassed) {
 556                                 return false;
 557                         }
 558                 }
 559
 560                 if (empty($block->args)) {
 561                         return $block->isVararg || empty($orderedArgs) && empty($keywordArgs);
 562                 }
 563
 564                 $remainingArgs = $block->args;
 565                 if ($keywordArgs) {
 566                         $remainingArgs = array();
 567                         foreach ($block->args as $arg) {
 568                                 if ($arg[0] == "arg" && isset($keywordArgs[$arg[1]])) {
 569                                         continue;
 570                                 }
 571
 572                                 $remainingArgs[] = $arg;
 573                         }
 574                 }
 575
 576                 $i = -1; // no args
 577                 // try to match by arity or by argument literal
 578                 foreach ($remainingArgs as $i => $arg) {
 579                         switch ($arg[0]) {
 580                         case "lit":
 581                                 if (empty($orderedArgs[$i]) || !$this->eq($arg[1], $orderedArgs[$i])) {
 582                                         return false;
 583                                 }
 584                                 break;
 585                         case "arg":
 586                                 // no arg and no default value
 587                                 if (!isset($orderedArgs[$i]) && !isset($arg[2])) {
 588                                         return false;
 589                                 }
 590                                 break;
 591                         case "rest":
 592                                 $i--; // rest can be empty
 593                                 break 2;
 594                         }
 595                 }
 596
 597                 if ($block->isVararg) {
 598                         return true; // not having enough is handled above
 599                 } else {
 600                         $numMatched = $i + 1;
 601                         // greater than becuase default values always match
 602                         return $numMatched >= count($orderedArgs);
 603                 }
 604         }
 605
 606         protected function patternMatchAll($blocks, $orderedArgs, $keywordArgs, $skip=array()) {
 607                 $matches = null;
 608                 foreach ($blocks as $block) {
 609                         // skip seen blocks that don't have arguments
 610                         if (isset($skip[$block->id]) && !isset($block->args)) {
 611                                 continue;
 612                         }
 613
 614                         if ($this->patternMatch($block, $orderedArgs, $keywordArgs)) {
 615                                 $matches[] = $block;
 616                         }
 617                 }
 618
 619                 return $matches;
 620         }
 621
 622         // attempt to find blocks matched by path and args
 623         protected function findBlocks($searchIn, $path, $orderedArgs, $keywordArgs, $seen=array()) {
 624                 if ($searchIn == null) return null;
 625                 if (isset($seen[$searchIn->id])) return null;
 626                 $seen[$searchIn->id] = true;
 627
 628                 $name = $path[0];
 629
 630                 if (isset($searchIn->children[$name])) {
 631                         $blocks = $searchIn->children[$name];
 632                         if (count($path) == 1) {
 633                                 $matches = $this->patternMatchAll($blocks, $orderedArgs, $keywordArgs, $seen);
 634                                 if (!empty($matches)) {
 635                                         // This will return all blocks that match in the closest
 636                                         // scope that has any matching block, like lessjs
 637                                         return $matches;
 638                                 }
 639                         } else {
 640                                 $matches = array();
 641                                 foreach ($blocks as $subBlock) {
 642                                         $subMatches = $this->findBlocks($subBlock,
 643                                                 array_slice($path, 1), $orderedArgs, $keywordArgs, $seen);
 644
 645                                         if (!is_null($subMatches)) {
 646                                                 foreach ($subMatches as $sm) {
 647                                                         $matches[] = $sm;
 648                                                 }
 649                                         }
 650                                 }
 651
 652                                 return count($matches) > 0 ? $matches : null;
 653                         }
 654                 }
 655                 if ($searchIn->parent === $searchIn) return null;
 656                 return $this->findBlocks($searchIn->parent, $path, $orderedArgs, $keywordArgs, $seen);
 657         }
 658
 659         // sets all argument names in $args to either the default value
 660         // or the one passed in through $values
 661         protected function zipSetArgs($args, $orderedValues, $keywordValues) {
 662                 $assignedValues = array();
 663
 664                 $i = 0;
 665                 foreach ($args as  $a) {
 666                         if ($a[0] == "arg") {
 667                                 if (isset($keywordValues[$a[1]])) {
 668                                         // has keyword arg
 669                                         $value = $keywordValues[$a[1]];
 670                                 } elseif (isset($orderedValues[$i])) {
 671                                         // has ordered arg
 672                                         $value = $orderedValues[$i];
 673                                         $i++;
 674                                 } elseif (isset($a[2])) {
 675                                         // has default value
 676                                         $value = $a[2];
 677                                 } else {
 678                                         $this->throwError("Failed to assign arg " . $a[1]);
 679                                         $value = null; // :(
 680                                 }
 681
 682                                 $value = $this->reduce($value);
 683                                 $this->set($a[1], $value);
 684                                 $assignedValues[] = $value;
 685                         } else {
 686                                 // a lit
 687                                 $i++;
 688                         }
 689                 }
 690
 691                 // check for a rest
 692                 $last = end($args);
 693                 if ($last[0] == "rest") {
 694                         $rest = array_slice($orderedValues, count($args) - 1);
 695                         $this->set($last[1], $this->reduce(array("list", " ", $rest)));
 696                 }
 697
 698                 // wow is this the only true use of PHP's + operator for arrays?
 699                 $this->env->arguments = $assignedValues + $orderedValues;
 700         }
 701
 702         // compile a prop and update $lines or $blocks appropriately
 703         protected function compileProp($prop, $block, $out) {
 704                 // set error position context
 705                 $this->sourceLoc = isset($prop[-1]) ? $prop[-1] : -1;
 706
 707                 switch ($prop[0]) {
 708                 case 'assign':
 709                         list(, $name, $value) = $prop;
 710                         if ($name[0] == $this->vPrefix) {
 711                                 $this->set($name, $value);
 712                         } else {
 713                                 $out->lines[] = $this->formatter->property($name,
 714                                                 $this->compileValue($this->reduce($value)));
 715                         }
 716                         break;
 717                 case 'block':
 718                         list(, $child) = $prop;
 719                         $this->compileBlock($child);
 720                         break;
 721                 case 'mixin':
 722                         list(, $path, $args, $suffix) = $prop;
 723
 724                         $orderedArgs = array();
 725                         $keywordArgs = array();
 726                         foreach ((array)$args as $arg) {
 727                                 $argval = null;
 728                                 switch ($arg[0]) {
 729                                 case "arg":
 730                                         if (!isset($arg[2])) {
 731                                                 $orderedArgs[] = $this->reduce(array("variable", $arg[1]));
 732                                         } else {
 733                                                 $keywordArgs[$arg[1]] = $this->reduce($arg[2]);
 734                                         }
 735                                         break;
 736
 737                                 case "lit":
 738                                         $orderedArgs[] = $this->reduce($arg[1]);
 739                                         break;
 740                                 default:
 741                                         $this->throwError("Unknown arg type: " . $arg[0]);
 742                                 }
 743                         }
 744
 745                         $mixins = $this->findBlocks($block, $path, $orderedArgs, $keywordArgs);
 746
 747                         if ($mixins === null) {
 748                                 $this->throwError("{$prop[1][0]} is undefined");
 749                         }
 750
 751                         foreach ($mixins as $mixin) {
 752                                 if ($mixin === $block && !$orderedArgs) {
 753                                         continue;
 754                                 }
 755
 756                                 $haveScope = false;
 757                                 if (isset($mixin->parent->scope)) {
 758                                         $haveScope = true;
 759                                         $mixinParentEnv = $this->pushEnv();
 760                                         $mixinParentEnv->storeParent = $mixin->parent->scope;
 761                                 }
 762
 763                                 $haveArgs = false;
 764                                 if (isset($mixin->args)) {
 765                                         $haveArgs = true;
 766                                         $this->pushEnv();
 767                                         $this->zipSetArgs($mixin->args, $orderedArgs, $keywordArgs);
 768                                 }
 769
 770                                 $oldParent = $mixin->parent;
 771                                 if ($mixin != $block) $mixin->parent = $block;
 772
 773                                 foreach ($this->sortProps($mixin->props) as $subProp) {
 774                                         if ($suffix !== null &&
 775                                                 $subProp[0] == "assign" &&
 776                                                 is_string($subProp[1]) &&
 777                                                 $subProp[1]{0} != $this->vPrefix)
 778                                         {
 779                                                 $subProp[2] = array(
 780                                                         'list', ' ',
 781                                                         array($subProp[2], array('keyword', $suffix))
 782                                                 );
 783                                         }
 784
 785                                         $this->compileProp($subProp, $mixin, $out);
 786                                 }
 787
 788                                 $mixin->parent = $oldParent;
 789
 790                                 if ($haveArgs) $this->popEnv();
 791                                 if ($haveScope) $this->popEnv();
 792                         }
 793
 794                         break;
 795                 case 'raw':
 796                         $out->lines[] = $prop[1];
 797                         break;
 798                 case "directive":
 799                         list(, $name, $value) = $prop;
 800                         $out->lines[] = "@$name " . $this->compileValue($this->reduce($value)).';';
 801                         break;
 802                 case "comment":
 803                         $out->lines[] = $prop[1];
 804                         break;
 805                 case "import";
 806                         list(, $importPath, $importId) = $prop;
 807                         $importPath = $this->reduce($importPath);
 808
 809                         if (!isset($this->env->imports)) {
 810                                 $this->env->imports = array();
 811                         }
 812
 813                         $result = $this->tryImport($importPath, $block, $out);
 814
 815                         $this->env->imports[$importId] = $result === false ?
 816                                 array(false, "@import " . $this->compileValue($importPath).";") :
 817                                 $result;
 818
 819                         break;
 820                 case "import_mixin":
 821                         list(,$importId) = $prop;
 822                         $import = $this->env->imports[$importId];
 823                         if ($import[0] === false) {
 824                                 if (isset($import[1])) {
 825                                         $out->lines[] = $import[1];
 826                                 }
 827                         } else {
 828                                 list(, $bottom, $parser, $importDir) = $import;
 829                                 $this->compileImportedProps($bottom, $block, $out, $parser, $importDir);
 830                         }
 831
 832                         break;
 833                 default:
 834                         $this->throwError("unknown op: {$prop[0]}\n");
 835                 }
 836         }
 837
 838
 839         /**
 840          * Compiles a primitive value into a CSS property value.
 841          *
 842          * Values in lessphp are typed by being wrapped in arrays, their format is
 843          * typically:
 844          *
 845          *     array(type, contents [, additional_contents]*)
 846          *
 847          * The input is expected to be reduced. This function will not work on
 848          * things like expressions and variables.
 849          */
 850         public function compileValue($value) {
 851                 switch ($value[0]) {
 852                 case 'list':
 853                         // [1] - delimiter
 854                         // [2] - array of values
 855                         return implode($value[1], array_map(array($this, 'compileValue'), $value[2]));
 856                 case 'raw_color':
 857                         if (!empty($this->formatter->compressColors)) {
 858                                 return $this->compileValue($this->coerceColor($value));
 859                         }
 860                         return $value[1];
 861                 case 'keyword':
 862                         // [1] - the keyword
 863                         return $value[1];
 864                 case 'number':
 865                         list(, $num, $unit) = $value;
 866                         // [1] - the number
 867                         // [2] - the unit
 868                         if ($this->numberPrecision !== null) {
 869                                 $num = round($num, $this->numberPrecision);
 870                         }
 871                         return $num . $unit;
 872                 case 'string':
 873                         // [1] - contents of string (includes quotes)
 874                         list(, $delim, $content) = $value;
 875                         foreach ($content as &$part) {
 876                                 if (is_array($part)) {
 877                                         $part = $this->compileValue($part);
 878                                 }
 879                         }
 880                         return $delim . implode($content) . $delim;
 881                 case 'color':
 882                         // [1] - red component (either number or a %)
 883                         // [2] - green component
 884                         // [3] - blue component
 885                         // [4] - optional alpha component
 886                         list(, $r, $g, $b) = $value;
 887                         $r = round($r);
 888                         $g = round($g);
 889                         $b = round($b);
 890
 891                         if (count($value) == 5 && $value[4] != 1) { // rgba
 892                                 return 'rgba('.$r.','.$g.','.$b.','.$value[4].')';
 893                         }
 894
 895                         $h = sprintf("#%02x%02x%02x", $r, $g, $b);
 896
 897                         if (!empty($this->formatter->compressColors)) {
 898                                 // Converting hex color to short notation (e.g. #003399 to #039)
 899                                 if ($h[1] === $h[2] && $h[3] === $h[4] && $h[5] === $h[6]) {
 900                                         $h = '#' . $h[1] . $h[3] . $h[5];
 901                                 }
 902                         }
 903
 904                         return $h;
 905
 906                 case 'function':
 907                         list(, $name, $args) = $value;
 908                         return $name.'('.$this->compileValue($args).')';
 909                 default: // assumed to be unit
 910                         $this->throwError("unknown value type: $value[0]");
 911                 }
 912         }
 913
 914         protected function lib_pow($args) {
 915                 list($base, $exp) = $this->assertArgs($args, 2, "pow");
 916                 return pow($this->assertNumber($base), $this->assertNumber($exp));
 917         }
 918
 919         protected function lib_pi() {
 920                 return pi();
 921         }
 922
 923         protected function lib_mod($args) {
 924                 list($a, $b) = $this->assertArgs($args, 2, "mod");
 925                 return $this->assertNumber($a) % $this->assertNumber($b);
 926         }
 927
 928         protected function lib_tan($num) {
 929                 return tan($this->assertNumber($num));
 930         }
 931
 932         protected function lib_sin($num) {
 933                 return sin($this->assertNumber($num));
 934         }
 935
 936         protected function lib_cos($num) {
 937                 return cos($this->assertNumber($num));
 938         }
 939
 940         protected function lib_atan($num) {
 941                 $num = atan($this->assertNumber($num));
 942                 return array("number", $num, "rad");
 943         }
 944
 945         protected function lib_asin($num) {
 946                 $num = asin($this->assertNumber($num));
 947                 return array("number", $num, "rad");
 948         }
 949
 950         protected function lib_acos($num) {
 951                 $num = acos($this->assertNumber($num));
 952                 return array("number", $num, "rad");
 953         }
 954
 955         protected function lib_sqrt($num) {
 956                 return sqrt($this->assertNumber($num));
 957         }
 958
 959         protected function lib_extract($value) {
 960                 list($list, $idx) = $this->assertArgs($value, 2, "extract");
 961                 $idx = $this->assertNumber($idx);
 962                 // 1 indexed
 963                 if ($list[0] == "list" && isset($list[2][$idx - 1])) {
 964                         return $list[2][$idx - 1];
 965                 }
 966         }
 967
 968         protected function lib_isnumber($value) {
 969                 return $this->toBool($value[0] == "number");
 970         }
 971
 972         protected function lib_isstring($value) {
 973                 return $this->toBool($value[0] == "string");
 974         }
 975
 976         protected function lib_iscolor($value) {
 977                 return $this->toBool($this->coerceColor($value));
 978         }
 979
 980         protected function lib_iskeyword($value) {
 981                 return $this->toBool($value[0] == "keyword");
 982         }
 983
 984         protected function lib_ispixel($value) {
 985                 return $this->toBool($value[0] == "number" && $value[2] == "px");
 986         }
 987
 988         protected function lib_ispercentage($value) {
 989                 return $this->toBool($value[0] == "number" && $value[2] == "%");
 990         }
 991
 992         protected function lib_isem($value) {
 993                 return $this->toBool($value[0] == "number" && $value[2] == "em");
 994         }
 995
 996         protected function lib_isrem($value) {
 997                 return $this->toBool($value[0] == "number" && $value[2] == "rem");
 998         }
 999
1000         protected function lib_rgbahex($color) {
1001                 $color = $this->coerceColor($color);
1002                 if (is_null($color))
1003                         $this->throwError("color expected for rgbahex");
1004
1005                 return sprintf("#%02x%02x%02x%02x",
1006                         isset($color[4]) ? $color[4]*255 : 255,
1007                         $color[1],$color[2], $color[3]);
1008         }
1009
1010         protected function lib_argb($color){
1011                 return $this->lib_rgbahex($color);
1012         }
1013
1014         /**
1015          * Given an url, decide whether to output a regular link or the base64-encoded contents of the file
1016          *
1017          * @param  array  $value either an argument list (two strings) or a single string
1018          * @return string        formatted url(), either as a link or base64-encoded
1019          */
1020         protected function lib_data_uri($value) {
1021                 $mime = ($value[0] === 'list') ? $value[2][0][2] : null;
1022                 $url = ($value[0] === 'list') ? $value[2][1][2][0] : $value[2][0];
1023
1024                 $fullpath = $this->findImport($url);
1025
1026                 if($fullpath && ($fsize = filesize($fullpath)) !== false) {
1027                         // IE8 can't handle data uris larger than 32KB
1028                         if($fsize/1024 < 32) {
1029                                 if(is_null($mime)) {
1030                                         if(class_exists('finfo')) { // php 5.3+
1031                                                 $finfo = new finfo(FILEINFO_MIME);
1032                                                 $mime = explode('; ', $finfo->file($fullpath));
1033                                                 $mime = $mime[0];
1034                                         } elseif(function_exists('mime_content_type')) { // PHP 5.2
1035                                                 $mime = mime_content_type($fullpath);
1036                                         }
1037                                 }
1038
1039                                 if(!is_null($mime)) // fallback if the MIME type is still unknown
1040                                         $url = sprintf('data:%s;base64,%s', $mime, base64_encode(file_get_contents($fullpath)));
1041                         }
1042                 }
1043
1044                 return 'url("'.$url.'")';
1045         }
1046
1047         // utility func to unquote a string
1048         protected function lib_e($arg) {
1049                 switch ($arg[0]) {
1050                         case "list":
1051                                 $items = $arg[2];
1052                                 if (isset($items[0])) {
1053                                         return $this->lib_e($items[0]);
1054                                 }
1055                                 $this->throwError("unrecognised input");
1056                         case "string":
1057                                 $arg[1] = "";
1058                                 return $arg;
1059                         case "keyword":
1060                                 return $arg;
1061                         default:
1062                                 return array("keyword", $this->compileValue($arg));
1063                 }
1064         }
1065
1066         protected function lib__sprintf($args) {
1067                 if ($args[0] != "list") return $args;
1068                 $values = $args[2];
1069                 $string = array_shift($values);
1070                 $template = $this->compileValue($this->lib_e($string));
1071
1072                 $i = 0;
1073                 if (preg_match_all('/%[dsa]/', $template, $m)) {
1074                         foreach ($m[0] as $match) {
1075                                 $val = isset($values[$i]) ?
1076                                         $this->reduce($values[$i]) : array('keyword', '');
1077
1078                                 // lessjs compat, renders fully expanded color, not raw color
1079                                 if ($color = $this->coerceColor($val)) {
1080                                         $val = $color;
1081                                 }
1082
1083                                 $i++;
1084                                 $rep = $this->compileValue($this->lib_e($val));
1085                                 $template = preg_replace('/'.self::preg_quote($match).'/',
1086                                         $rep, $template, 1);
1087                         }
1088                 }
1089
1090                 $d = $string[0] == "string" ? $string[1] : '"';
1091                 return array("string", $d, array($template));
1092         }
1093
1094         protected function lib_floor($arg) {
1095                 $value = $this->assertNumber($arg);
1096                 return array("number", floor($value), $arg[2]);
1097         }
1098
1099         protected function lib_ceil($arg) {
1100                 $value = $this->assertNumber($arg);
1101                 return array("number", ceil($value), $arg[2]);
1102         }
1103
1104         protected function lib_round($arg) {
1105                 if($arg[0] != "list") {
1106                         $value = $this->assertNumber($arg);
1107                         return array("number", round($value), $arg[2]);
1108                 } else {
1109                         $value = $this->assertNumber($arg[2][0]);
1110                         $precision = $this->assertNumber($arg[2][1]);
1111                         return array("number", round($value, $precision), $arg[2][0][2]);
1112                 }
1113         }
1114
1115         protected function lib_unit($arg) {
1116                 if ($arg[0] == "list") {
1117                         list($number, $newUnit) = $arg[2];
1118                         return array("number", $this->assertNumber($number),
1119                                 $this->compileValue($this->lib_e($newUnit)));
1120                 } else {
1121                         return array("number", $this->assertNumber($arg), "");
1122                 }
1123         }
1124
1125         /**
1126          * Helper function to get arguments for color manipulation functions.
1127          * takes a list that contains a color like thing and a percentage
1128          */
1129         public function colorArgs($args) {
1130                 if ($args[0] != 'list' || count($args[2]) < 2) {
1131                         return array(array('color', 0, 0, 0), 0);
1132                 }
1133                 list($color, $delta) = $args[2];
1134                 $color = $this->assertColor($color);
1135                 $delta = floatval($delta[1]);
1136
1137                 return array($color, $delta);
1138         }
1139
1140         protected function lib_darken($args) {
1141                 list($color, $delta) = $this->colorArgs($args);
1142
1143                 $hsl = $this->toHSL($color);
1144                 $hsl[3] = $this->clamp($hsl[3] - $delta, 100);
1145                 return $this->toRGB($hsl);
1146         }
1147
1148         protected function lib_lighten($args) {
1149                 list($color, $delta) = $this->colorArgs($args);
1150
1151                 $hsl = $this->toHSL($color);
1152                 $hsl[3] = $this->clamp($hsl[3] + $delta, 100);
1153                 return $this->toRGB($hsl);
1154         }
1155
1156         protected function lib_saturate($args) {
1157                 list($color, $delta) = $this->colorArgs($args);
1158
1159                 $hsl = $this->toHSL($color);
1160                 $hsl[2] = $this->clamp($hsl[2] + $delta, 100);
1161                 return $this->toRGB($hsl);
1162         }
1163
1164         protected function lib_desaturate($args) {
1165                 list($color, $delta) = $this->colorArgs($args);
1166
1167                 $hsl = $this->toHSL($color);
1168                 $hsl[2] = $this->clamp($hsl[2] - $delta, 100);
1169                 return $this->toRGB($hsl);
1170         }
1171
1172         protected function lib_spin($args) {
1173                 list($color, $delta) = $this->colorArgs($args);
1174
1175                 $hsl = $this->toHSL($color);
1176
1177                 $hsl[1] = $hsl[1] + $delta % 360;
1178                 if ($hsl[1] < 0) $hsl[1] += 360;
1179
1180                 return $this->toRGB($hsl);
1181         }
1182
1183         protected function lib_fadeout($args) {
1184                 list($color, $delta) = $this->colorArgs($args);
1185                 $color[4] = $this->clamp((isset($color[4]) ? $color[4] : 1) - $delta/100);
1186                 return $color;
1187         }
1188
1189         protected function lib_fadein($args) {
1190                 list($color, $delta) = $this->colorArgs($args);
1191                 $color[4] = $this->clamp((isset($color[4]) ? $color[4] : 1) + $delta/100);
1192                 return $color;
1193         }
1194
1195         protected function lib_hue($color) {
1196                 $hsl = $this->toHSL($this->assertColor($color));
1197                 return round($hsl[1]);
1198         }
1199
1200         protected function lib_saturation($color) {
1201                 $hsl = $this->toHSL($this->assertColor($color));
1202                 return round($hsl[2]);
1203         }
1204
1205         protected function lib_lightness($color) {
1206                 $hsl = $this->toHSL($this->assertColor($color));
1207                 return round($hsl[3]);
1208         }
1209
1210         // get the alpha of a color
1211         // defaults to 1 for non-colors or colors without an alpha
1212         protected function lib_alpha($value) {
1213                 if (!is_null($color = $this->coerceColor($value))) {
1214                         return isset($color[4]) ? $color[4] : 1;
1215                 }
1216         }
1217
1218         // set the alpha of the color
1219         protected function lib_fade($args) {
1220                 list($color, $alpha) = $this->colorArgs($args);
1221                 $color[4] = $this->clamp($alpha / 100.0);
1222                 return $color;
1223         }
1224
1225         protected function lib_percentage($arg) {
1226                 $num = $this->assertNumber($arg);
1227                 return array("number", $num*100, "%");
1228         }
1229
1230         // mixes two colors by weight
1231         // mix(@color1, @color2, [@weight: 50%]);
1232         // http://sass-lang.com/docs/yardoc/Sass/Script/Functions.html#mix-instance_method
1233         protected function lib_mix($args) {
1234                 if ($args[0] != "list" || count($args[2]) < 2)
1235                         $this->throwError("mix expects (color1, color2, weight)");
1236
1237                 list($first, $second) = $args[2];
1238                 $first = $this->assertColor($first);
1239                 $second = $this->assertColor($second);
1240
1241                 $first_a = $this->lib_alpha($first);
1242                 $second_a = $this->lib_alpha($second);
1243
1244                 if (isset($args[2][2])) {
1245                         $weight = $args[2][2][1] / 100.0;
1246                 } else {
1247                         $weight = 0.5;
1248                 }
1249
1250                 $w = $weight * 2 - 1;
1251                 $a = $first_a - $second_a;
1252
1253                 $w1 = (($w * $a == -1 ? $w : ($w + $a)/(1 + $w * $a)) + 1) / 2.0;
1254                 $w2 = 1.0 - $w1;
1255
1256                 $new = array('color',
1257                         $w1 * $first[1] + $w2 * $second[1],
1258                         $w1 * $first[2] + $w2 * $second[2],
1259                         $w1 * $first[3] + $w2 * $second[3],
1260                 );
1261
1262                 if ($first_a != 1.0 || $second_a != 1.0) {
1263                         $new[] = $first_a * $weight + $second_a * ($weight - 1);
1264                 }
1265
1266                 return $this->fixColor($new);
1267         }
1268
1269         protected function lib_contrast($args) {
1270             $darkColor  = array('color', 0, 0, 0);
1271             $lightColor = array('color', 255, 255, 255);
1272             $threshold  = 0.43;
1273
1274             if ( $args[0] == 'list' ) {
1275                 $inputColor = ( isset($args[2][0]) ) ? $this->assertColor($args[2][0])  : $lightColor;
1276                 $darkColor  = ( isset($args[2][1]) ) ? $this->assertColor($args[2][1])  : $darkColor;
1277                 $lightColor = ( isset($args[2][2]) ) ? $this->assertColor($args[2][2])  : $lightColor;
1278                 $threshold  = ( isset($args[2][3]) ) ? $this->assertNumber($args[2][3]) : $threshold;
1279             }
1280             else {
1281                 $inputColor  = $this->assertColor($args);
1282             }
1283
1284             $inputColor = $this->coerceColor($inputColor);
1285             $darkColor  = $this->coerceColor($darkColor);
1286             $lightColor = $this->coerceColor($lightColor);
1287
1288             //Figure out which is actually light and dark!
1289             if ( $this->lib_luma($darkColor) > $this->lib_luma($lightColor) ) {
1290                 $t  = $lightColor;
1291                 $lightColor = $darkColor;
1292                 $darkColor  = $t;
1293             }
1294
1295             $inputColor_alpha = $this->lib_alpha($inputColor);
1296             if ( ( $this->lib_luma($inputColor) * $inputColor_alpha) < $threshold) {
1297                 return $lightColor;
1298             }
1299             return $darkColor;
1300         }
1301
1302         protected function lib_luma($color) {
1303             $color = $this->coerceColor($color);
1304             return (0.2126 * $color[0] / 255) + (0.7152 * $color[1] / 255) + (0.0722 * $color[2] / 255);
1305         }
1306
1307
1308         public function assertColor($value, $error = "expected color value") {
1309                 $color = $this->coerceColor($value);
1310                 if (is_null($color)) $this->throwError($error);
1311                 return $color;
1312         }
1313
1314         public function assertNumber($value, $error = "expecting number") {
1315                 if ($value[0] == "number") return $value[1];
1316                 $this->throwError($error);
1317         }
1318
1319         public function assertArgs($value, $expectedArgs, $name="") {
1320                 if ($expectedArgs == 1) {
1321                         return $value;
1322                 } else {
1323                         if ($value[0] !== "list" || $value[1] != ",") $this->throwError("expecting list");
1324                         $values = $value[2];
1325                         $numValues = count($values);
1326                         if ($expectedArgs != $numValues) {
1327                                 if ($name) {
1328                                         $name = $name . ": ";
1329                                 }
1330
1331                                 $this->throwError("${name}expecting $expectedArgs arguments, got $numValues");
1332                         }
1333
1334                         return $values;
1335                 }
1336         }
1337
1338         protected function toHSL($color) {
1339                 if ($color[0] == 'hsl') return $color;
1340
1341                 $r = $color[1] / 255;
1342                 $g = $color[2] / 255;
1343                 $b = $color[3] / 255;
1344
1345                 $min = min($r, $g, $b);
1346                 $max = max($r, $g, $b);
1347
1348                 $L = ($min + $max) / 2;
1349                 if ($min == $max) {
1350                         $S = $H = 0;
1351                 } else {
1352                         if ($L < 0.5)
1353                                 $S = ($max - $min)/($max + $min);
1354                         else
1355                                 $S = ($max - $min)/(2.0 - $max - $min);
1356
1357                         if ($r == $max) $H = ($g - $b)/($max - $min);
1358                         elseif ($g == $max) $H = 2.0 + ($b - $r)/($max - $min);
1359                         elseif ($b == $max) $H = 4.0 + ($r - $g)/($max - $min);
1360
1361                 }
1362
1363                 $out = array('hsl',
1364                         ($H < 0 ? $H + 6 : $H)*60,
1365                         $S*100,
1366                         $L*100,
1367                 );
1368
1369                 if (count($color) > 4) $out[] = $color[4]; // copy alpha
1370                 return $out;
1371         }
1372
1373         protected function toRGB_helper($comp, $temp1, $temp2) {
1374                 if ($comp < 0) $comp += 1.0;
1375                 elseif ($comp > 1) $comp -= 1.0;
1376
1377                 if (6 * $comp < 1) return $temp1 + ($temp2 - $temp1) * 6 * $comp;
1378                 if (2 * $comp < 1) return $temp2;
1379                 if (3 * $comp < 2) return $temp1 + ($temp2 - $temp1)*((2/3) - $comp) * 6;
1380
1381                 return $temp1;
1382         }
1383
1384         /**
1385          * Converts a hsl array into a color value in rgb.
1386          * Expects H to be in range of 0 to 360, S and L in 0 to 100
1387          */
1388         protected function toRGB($color) {
1389                 if ($color[0] == 'color') return $color;
1390
1391                 $H = $color[1] / 360;
1392                 $S = $color[2] / 100;
1393                 $L = $color[3] / 100;
1394
1395                 if ($S == 0) {
1396                         $r = $g = $b = $L;
1397                 } else {
1398                         $temp2 = $L < 0.5 ?
1399                                 $L*(1.0 + $S) :
1400                                 $L + $S - $L * $S;
1401
1402                         $temp1 = 2.0 * $L - $temp2;
1403
1404                         $r = $this->toRGB_helper($H + 1/3, $temp1, $temp2);
1405                         $g = $this->toRGB_helper($H, $temp1, $temp2);
1406                         $b = $this->toRGB_helper($H - 1/3, $temp1, $temp2);
1407                 }
1408
1409                 // $out = array('color', round($r*255), round($g*255), round($b*255));
1410                 $out = array('color', $r*255, $g*255, $b*255);
1411                 if (count($color) > 4) $out[] = $color[4]; // copy alpha
1412                 return $out;
1413         }
1414
1415         protected function clamp($v, $max = 1, $min = 0) {
1416                 return min($max, max($min, $v));
1417         }
1418
1419         /**
1420          * Convert the rgb, rgba, hsl color literals of function type
1421          * as returned by the parser into values of color type.
1422          */
1423         protected function funcToColor($func) {
1424                 $fname = $func[1];
1425                 if ($func[2][0] != 'list') return false; // need a list of arguments
1426                 $rawComponents = $func[2][2];
1427
1428                 if ($fname == 'hsl' || $fname == 'hsla') {
1429                         $hsl = array('hsl');
1430                         $i = 0;
1431                         foreach ($rawComponents as $c) {
1432                                 $val = $this->reduce($c);
1433                                 $val = isset($val[1]) ? floatval($val[1]) : 0;
1434
1435                                 if ($i == 0) $clamp = 360;
1436                                 elseif ($i < 3) $clamp = 100;
1437                                 else $clamp = 1;
1438
1439                                 $hsl[] = $this->clamp($val, $clamp);
1440                                 $i++;
1441                         }
1442
1443                         while (count($hsl) < 4) $hsl[] = 0;
1444                         return $this->toRGB($hsl);
1445
1446                 } elseif ($fname == 'rgb' || $fname == 'rgba') {
1447                         $components = array();
1448                         $i = 1;
1449                         foreach ($rawComponents as $c) {
1450                                 $c = $this->reduce($c);
1451                                 if ($i < 4) {
1452                                         if ($c[0] == "number" && $c[2] == "%") {
1453                                                 $components[] = 255 * ($c[1] / 100);
1454                                         } else {
1455                                                 $components[] = floatval($c[1]);
1456                                         }
1457                                 } elseif ($i == 4) {
1458                                         if ($c[0] == "number" && $c[2] == "%") {
1459                                                 $components[] = 1.0 * ($c[1] / 100);
1460                                         } else {
1461                                                 $components[] = floatval($c[1]);
1462                                         }
1463                                 } else break;
1464
1465                                 $i++;
1466                         }
1467                         while (count($components) < 3) $components[] = 0;
1468                         array_unshift($components, 'color');
1469                         return $this->fixColor($components);
1470                 }
1471
1472                 return false;
1473         }
1474
1475         protected function reduce($value, $forExpression = false) {
1476                 switch ($value[0]) {
1477                 case "interpolate":
1478                         $reduced = $this->reduce($value[1]);
1479                         $var = $this->compileValue($reduced);
1480                         $res = $this->reduce(array("variable", $this->vPrefix . $var));
1481
1482                         if ($res[0] == "raw_color") {
1483                                 $res = $this->coerceColor($res);
1484                         }
1485
1486                         if (empty($value[2])) $res = $this->lib_e($res);
1487
1488                         return $res;
1489                 case "variable":
1490                         $key = $value[1];
1491                         if (is_array($key)) {
1492                                 $key = $this->reduce($key);
1493                                 $key = $this->vPrefix . $this->compileValue($this->lib_e($key));
1494                         }
1495
1496                         $seen =& $this->env->seenNames;
1497
1498                         if (!empty($seen[$key])) {
1499                                 $this->throwError("infinite loop detected: $key");
1500                         }
1501
1502                         $seen[$key] = true;
1503                         $out = $this->reduce($this->get($key));
1504                         $seen[$key] = false;
1505                         return $out;
1506                 case "list":
1507                         foreach ($value[2] as &$item) {
1508                                 $item = $this->reduce($item, $forExpression);
1509                         }
1510                         return $value;
1511                 case "expression":
1512                         return $this->evaluate($value);
1513                 case "string":
1514                         foreach ($value[2] as &$part) {
1515                                 if (is_array($part)) {
1516                                         $strip = $part[0] == "variable";
1517                                         $part = $this->reduce($part);
1518                                         if ($strip) $part = $this->lib_e($part);
1519                                 }
1520                         }
1521                         return $value;
1522                 case "escape":
1523                         list(,$inner) = $value;
1524                         return $this->lib_e($this->reduce($inner));
1525                 case "function":
1526                         $color = $this->funcToColor($value);
1527                         if ($color) return $color;
1528
1529                         list(, $name, $args) = $value;
1530                         if ($name == "%") $name = "_sprintf";
1531
1532                         $f = isset($this->libFunctions[$name]) ?
1533                                 $this->libFunctions[$name] : array($this, 'lib_'.str_replace('-', '_', $name));
1534
1535                         if (is_callable($f)) {
1536                                 if ($args[0] == 'list')
1537                                         $args = self::compressList($args[2], $args[1]);
1538
1539                                 $ret = call_user_func($f, $this->reduce($args, true), $this);
1540
1541                                 if (is_null($ret)) {
1542                                         return array("string", "", array(
1543                                                 $name, "(", $args, ")"
1544                                         ));
1545                                 }
1546
1547                                 // convert to a typed value if the result is a php primitive
1548                                 if (is_numeric($ret)) $ret = array('number', $ret, "");
1549                                 elseif (!is_array($ret)) $ret = array('keyword', $ret);
1550
1551                                 return $ret;
1552                         }
1553
1554                         // plain function, reduce args
1555                         $value[2] = $this->reduce($value[2]);
1556                         return $value;
1557                 case "unary":
1558                         list(, $op, $exp) = $value;
1559                         $exp = $this->reduce($exp);
1560
1561                         if ($exp[0] == "number") {
1562                                 switch ($op) {
1563                                 case "+":
1564                                         return $exp;
1565                                 case "-":
1566                                         $exp[1] *= -1;
1567                                         return $exp;
1568                                 }
1569                         }
1570                         return array("string", "", array($op, $exp));
1571                 }
1572
1573                 if ($forExpression) {
1574                         switch ($value[0]) {
1575                         case "keyword":
1576                                 if ($color = $this->coerceColor($value)) {
1577                                         return $color;
1578                                 }
1579                                 break;
1580                         case "raw_color":
1581                                 return $this->coerceColor($value);
1582                         }
1583                 }
1584
1585                 return $value;
1586         }
1587
1588
1589         // coerce a value for use in color operation
1590         protected function coerceColor($value) {
1591                 switch($value[0]) {
1592                         case 'color': return $value;
1593                         case 'raw_color':
1594                                 $c = array("color", 0, 0, 0);
1595                                 $colorStr = substr($value[1], 1);
1596                                 $num = hexdec($colorStr);
1597                                 $width = strlen($colorStr) == 3 ? 16 : 256;
1598
1599                                 for ($i = 3; $i > 0; $i--) { // 3 2 1
1600                                         $t = $num % $width;
1601                                         $num /= $width;
1602
1603                                         $c[$i] = $t * (256/$width) + $t * floor(16/$width);
1604                                 }
1605
1606                                 return $c;
1607                         case 'keyword':
1608                                 $name = $value[1];
1609                                 if (isset(self::$cssColors[$name])) {
1610                                         $rgba = explode(',', self::$cssColors[$name]);
1611
1612                                         if(isset($rgba[3]))
1613                                                 return array('color', $rgba[0], $rgba[1], $rgba[2], $rgba[3]);
1614
1615                                         return array('color', $rgba[0], $rgba[1], $rgba[2]);
1616                                 }
1617                                 return null;
1618                 }
1619         }
1620
1621         // make something string like into a string
1622         protected function coerceString($value) {
1623                 switch ($value[0]) {
1624                 case "string":
1625                         return $value;
1626                 case "keyword":
1627                         return array("string", "", array($value[1]));
1628                 }
1629                 return null;
1630         }
1631
1632         // turn list of length 1 into value type
1633         protected function flattenList($value) {
1634                 if ($value[0] == "list" && count($value[2]) == 1) {
1635                         return $this->flattenList($value[2][0]);
1636                 }
1637                 return $value;
1638         }
1639
1640         public function toBool($a) {
1641                 if ($a) return self::$TRUE;
1642                 else return self::$FALSE;
1643         }
1644
1645         // evaluate an expression
1646         protected function evaluate($exp) {
1647                 list(, $op, $left, $right, $whiteBefore, $whiteAfter) = $exp;
1648
1649                 $left = $this->reduce($left, true);
1650                 $right = $this->reduce($right, true);
1651
1652                 if ($leftColor = $this->coerceColor($left)) {
1653                         $left = $leftColor;
1654                 }
1655
1656                 if ($rightColor = $this->coerceColor($right)) {
1657                         $right = $rightColor;
1658                 }
1659
1660                 $ltype = $left[0];
1661                 $rtype = $right[0];
1662
1663                 // operators that work on all types
1664                 if ($op == "and") {
1665                         return $this->toBool($left == self::$TRUE && $right == self::$TRUE);
1666                 }
1667
1668                 if ($op == "=") {
1669                         return $this->toBool($this->eq($left, $right) );
1670                 }
1671
1672                 if ($op == "+" && !is_null($str = $this->stringConcatenate($left, $right))) {
1673                         return $str;
1674                 }
1675
1676                 // type based operators
1677                 $fname = "op_${ltype}_${rtype}";
1678                 if (is_callable(array($this, $fname))) {
1679                         $out = $this->$fname($op, $left, $right);
1680                         if (!is_null($out)) return $out;
1681                 }
1682
1683                 // make the expression look it did before being parsed
1684                 $paddedOp = $op;
1685                 if ($whiteBefore) $paddedOp = " " . $paddedOp;
1686                 if ($whiteAfter) $paddedOp .= " ";
1687
1688                 return array("string", "", array($left, $paddedOp, $right));
1689         }
1690
1691         protected function stringConcatenate($left, $right) {
1692                 if ($strLeft = $this->coerceString($left)) {
1693                         if ($right[0] == "string") {
1694                                 $right[1] = "";
1695                         }
1696                         $strLeft[2][] = $right;
1697                         return $strLeft;
1698                 }
1699
1700                 if ($strRight = $this->coerceString($right)) {
1701                         array_unshift($strRight[2], $left);
1702                         return $strRight;
1703                 }
1704         }
1705
1706
1707         // make sure a color's components don't go out of bounds
1708         protected function fixColor($c) {
1709                 foreach (range(1, 3) as $i) {
1710                         if ($c[$i] < 0) $c[$i] = 0;
1711                         if ($c[$i] > 255) $c[$i] = 255;
1712                 }
1713
1714                 return $c;
1715         }
1716
1717         protected function op_number_color($op, $lft, $rgt) {
1718                 if ($op == '+' || $op == '*') {
1719                         return $this->op_color_number($op, $rgt, $lft);
1720                 }
1721         }
1722
1723         protected function op_color_number($op, $lft, $rgt) {
1724                 if ($rgt[0] == '%') $rgt[1] /= 100;
1725
1726                 return $this->op_color_color($op, $lft,
1727                         array_fill(1, count($lft) - 1, $rgt[1]));
1728         }
1729
1730         protected function op_color_color($op, $left, $right) {
1731                 $out = array('color');
1732                 $max = count($left) > count($right) ? count($left) : count($right);
1733                 foreach (range(1, $max - 1) as $i) {
1734                         $lval = isset($left[$i]) ? $left[$i] : 0;
1735                         $rval = isset($right[$i]) ? $right[$i] : 0;
1736                         switch ($op) {
1737                         case '+':
1738                                 $out[] = $lval + $rval;
1739                                 break;
1740                         case '-':
1741                                 $out[] = $lval - $rval;
1742                                 break;
1743                         case '*':
1744                                 $out[] = $lval * $rval;
1745                                 break;
1746                         case '%':
1747                                 $out[] = $lval % $rval;
1748                                 break;
1749                         case '/':
1750                                 if ($rval == 0) $this->throwError("evaluate error: can't divide by zero");
1751                                 $out[] = $lval / $rval;
1752                                 break;
1753                         default:
1754                                 $this->throwError('evaluate error: color op number failed on op '.$op);
1755                         }
1756                 }
1757                 return $this->fixColor($out);
1758         }
1759
1760         function lib_red($color){
1761                 $color = $this->coerceColor($color);
1762                 if (is_null($color)) {
1763                         $this->throwError('color expected for red()');
1764                 }
1765
1766                 return $color[1];
1767         }
1768
1769         function lib_green($color){
1770                 $color = $this->coerceColor($color);
1771                 if (is_null($color)) {
1772                         $this->throwError('color expected for green()');
1773                 }
1774
1775                 return $color[2];
1776         }
1777
1778         function lib_blue($color){
1779                 $color = $this->coerceColor($color);
1780                 if (is_null($color)) {
1781                         $this->throwError('color expected for blue()');
1782                 }
1783
1784                 return $color[3];
1785         }
1786
1787
1788         // operator on two numbers
1789         protected function op_number_number($op, $left, $right) {
1790                 $unit = empty($left[2]) ? $right[2] : $left[2];
1791
1792                 $value = 0;
1793                 switch ($op) {
1794                 case '+':
1795                         $value = $left[1] + $right[1];
1796                         break;
1797                 case '*':
1798                         $value = $left[1] * $right[1];
1799                         break;
1800                 case '-':
1801                         $value = $left[1] - $right[1];
1802                         break;
1803                 case '%':
1804                         $value = $left[1] % $right[1];
1805                         break;
1806                 case '/':
1807                         if ($right[1] == 0) $this->throwError('parse error: divide by zero');
1808                         $value = $left[1] / $right[1];
1809                         break;
1810                 case '<':
1811                         return $this->toBool($left[1] < $right[1]);
1812                 case '>':
1813                         return $this->toBool($left[1] > $right[1]);
1814                 case '>=':
1815                         return $this->toBool($left[1] >= $right[1]);
1816                 case '=<':
1817                         return $this->toBool($left[1] <= $right[1]);
1818                 default:
1819                         $this->throwError('parse error: unknown number operator: '.$op);
1820                 }
1821
1822                 return array("number", $value, $unit);
1823         }
1824
1825
1826         /* environment functions */
1827
1828         protected function makeOutputBlock($type, $selectors = null) {
1829                 $b = new stdclass;
1830                 $b->lines = array();
1831                 $b->children = array();
1832                 $b->selectors = $selectors;
1833                 $b->type = $type;
1834                 $b->parent = $this->scope;
1835                 return $b;
1836         }
1837
1838         // the state of execution
1839         protected function pushEnv($block = null) {
1840                 $e = new stdclass;
1841                 $e->parent = $this->env;
1842                 $e->store = array();
1843                 $e->block = $block;
1844
1845                 $this->env = $e;
1846                 return $e;
1847         }
1848
1849         // pop something off the stack
1850         protected function popEnv() {
1851                 $old = $this->env;
1852                 $this->env = $this->env->parent;
1853                 return $old;
1854         }
1855
1856         // set something in the current env
1857         protected function set($name, $value) {
1858                 $this->env->store[$name] = $value;
1859         }
1860
1861
1862         // get the highest occurrence entry for a name
1863         protected function get($name) {
1864                 $current = $this->env;
1865
1866                 $isArguments = $name == $this->vPrefix . 'arguments';
1867                 while ($current) {
1868                         if ($isArguments && isset($current->arguments)) {
1869                                 return array('list', ' ', $current->arguments);
1870                         }
1871
1872                         if (isset($current->store[$name]))
1873                                 return $current->store[$name];
1874                         else {
1875                                 $current = isset($current->storeParent) ?
1876                                         $current->storeParent : $current->parent;
1877                         }
1878                 }
1879
1880                 $this->throwError("variable $name is undefined");
1881         }
1882
1883         // inject array of unparsed strings into environment as variables
1884         protected function injectVariables($args) {
1885                 $this->pushEnv();
1886                 $parser = new lessc_parser($this, __METHOD__);
1887                 foreach ($args as $name => $strValue) {
1888                         if ($name{0} != '@') $name = '@'.$name;
1889                         $parser->count = 0;
1890                         $parser->buffer = (string)$strValue;
1891                         if (!$parser->propertyValue($value)) {
1892                                 throw new Exception("failed to parse passed in variable $name: $strValue");
1893                         }
1894
1895                         $this->set($name, $value);
1896                 }
1897         }
1898
1899         /**
1900          * Initialize any static state, can initialize parser for a file
1901          * $opts isn't used yet
1902          */
1903         public function __construct($fname = null) {
1904                 if ($fname !== null) {
1905                         // used for deprecated parse method
1906                         $this->_parseFile = $fname;
1907                 }
1908         }
1909
1910         public function compile($string, $name = null) {
1911                 $locale = setlocale(LC_NUMERIC, 0);
1912                 setlocale(LC_NUMERIC, "C");
1913
1914                 $this->parser = $this->makeParser($name);
1915                 $root = $this->parser->parse($string);
1916
1917                 $this->env = null;
1918                 $this->scope = null;
1919
1920                 $this->formatter = $this->newFormatter();
1921
1922                 if (!empty($this->registeredVars)) {
1923                         $this->injectVariables($this->registeredVars);
1924                 }
1925
1926                 $this->sourceParser = $this->parser; // used for error messages
1927                 $this->compileBlock($root);
1928
1929                 ob_start();
1930                 $this->formatter->block($this->scope);
1931                 $out = ob_get_clean();
1932                 setlocale(LC_NUMERIC, $locale);
1933                 return $out;
1934         }
1935
1936         public function compileFile($fname, $outFname = null) {
1937                 if (!is_readable($fname)) {
1938                         throw new Exception('load error: failed to find '.$fname);
1939                 }
1940
1941                 $pi = pathinfo($fname);
1942
1943                 $oldImport = $this->importDir;
1944
1945                 $this->importDir = (array)$this->importDir;
1946                 $this->importDir[] = $pi['dirname'].'/';
1947
1948                 $this->addParsedFile($fname);
1949
1950                 $out = $this->compile(file_get_contents($fname), $fname);
1951
1952                 $this->importDir = $oldImport;
1953
1954                 if ($outFname !== null) {
1955                         return file_put_contents($outFname, $out);
1956                 }
1957
1958                 return $out;
1959         }
1960
1961         // compile only if changed input has changed or output doesn't exist
1962         public function checkedCompile($in, $out) {
1963                 if (!is_file($out) || filemtime($in) > filemtime($out)) {
1964                         $this->compileFile($in, $out);
1965                         return true;
1966                 }
1967                 return false;
1968         }
1969
1970         /**
1971          * Execute lessphp on a .less file or a lessphp cache structure
1972          *
1973          * The lessphp cache structure contains information about a specific
1974          * less file having been parsed. It can be used as a hint for future
1975          * calls to determine whether or not a rebuild is required.
1976          *
1977          * The cache structure contains two important keys that may be used
1978          * externally:
1979          *
1980          * compiled: The final compiled CSS
1981          * updated: The time (in seconds) the CSS was last compiled
1982          *
1983          * The cache structure is a plain-ol' PHP associative array and can
1984          * be serialized and unserialized without a hitch.
1985          *
1986          * @param mixed $in Input
1987          * @param bool $force Force rebuild?
1988          * @return array lessphp cache structure
1989          */
1990         public function cachedCompile($in, $force = false) {
1991                 // assume no root
1992                 $root = null;
1993
1994                 if (is_string($in)) {
1995                         $root = $in;
1996                 } elseif (is_array($in) and isset($in['root'])) {
1997                         if ($force or ! isset($in['files'])) {
1998                                 // If we are forcing a recompile or if for some reason the
1999                                 // structure does not contain any file information we should
2000                                 // specify the root to trigger a rebuild.
2001                                 $root = $in['root'];
2002                         } elseif (isset($in['files']) and is_array($in['files'])) {
2003                                 foreach ($in['files'] as $fname => $ftime ) {
2004                                         if (!file_exists($fname) or filemtime($fname) > $ftime) {
2005                                                 // One of the files we knew about previously has changed
2006                                                 // so we should look at our incoming root again.
2007                                                 $root = $in['root'];
2008                                                 break;
2009                                         }
2010                                 }
2011                         }
2012                 } else {
2013                         // TODO: Throw an exception? We got neither a string nor something
2014                         // that looks like a compatible lessphp cache structure.
2015                         return null;
2016                 }
2017
2018                 if ($root !== null) {
2019                         // If we have a root value which means we should rebuild.
2020                         $out = array();
2021                         $out['root'] = $root;
2022                         $out['compiled'] = $this->compileFile($root);
2023                         $out['files'] = $this->allParsedFiles();
2024                         $out['updated'] = time();
2025                         return $out;
2026                 } else {
2027                         // No changes, pass back the structure
2028                         // we were given initially.
2029                         return $in;
2030                 }
2031
2032         }
2033
2034         // parse and compile buffer
2035         // This is deprecated
2036         public function parse($str = null, $initialVariables = null) {
2037                 if (is_array($str)) {
2038                         $initialVariables = $str;
2039                         $str = null;
2040                 }
2041
2042                 $oldVars = $this->registeredVars;
2043                 if ($initialVariables !== null) {
2044                         $this->setVariables($initialVariables);
2045                 }
2046
2047                 if ($str == null) {
2048                         if (empty($this->_parseFile)) {
2049                                 throw new exception("nothing to parse");
2050                         }
2051
2052                         $out = $this->compileFile($this->_parseFile);
2053                 } else {
2054                         $out = $this->compile($str);
2055                 }
2056
2057                 $this->registeredVars = $oldVars;
2058                 return $out;
2059         }
2060
2061         protected function makeParser($name) {
2062                 $parser = new lessc_parser($this, $name);
2063                 $parser->writeComments = $this->preserveComments;
2064
2065                 return $parser;
2066         }
2067
2068         public function setFormatter($name) {
2069                 $this->formatterName = $name;
2070         }
2071
2072         protected function newFormatter() {
2073                 $className = "lessc_formatter_lessjs";
2074                 if (!empty($this->formatterName)) {
2075                         if (!is_string($this->formatterName))
2076                                 return $this->formatterName;
2077                         $className = "lessc_formatter_$this->formatterName";
2078                 }
2079
2080                 return new $className;
2081         }
2082
2083         public function setPreserveComments($preserve) {
2084                 $this->preserveComments = $preserve;
2085         }
2086
2087         public function registerFunction($name, $func) {
2088                 $this->libFunctions[$name] = $func;
2089         }
2090
2091         public function unregisterFunction($name) {
2092                 unset($this->libFunctions[$name]);
2093         }
2094
2095         public function setVariables($variables) {
2096                 $this->registeredVars = array_merge($this->registeredVars, $variables);
2097         }
2098
2099         public function unsetVariable($name) {
2100                 unset($this->registeredVars[$name]);
2101         }
2102
2103         public function setImportDir($dirs) {
2104                 $this->importDir = (array)$dirs;
2105         }
2106
2107         public function addImportDir($dir) {
2108                 $this->importDir = (array)$this->importDir;
2109                 $this->importDir[] = $dir;
2110         }
2111
2112         public function allParsedFiles() {
2113                 return $this->allParsedFiles;
2114         }
2115
2116         public function addParsedFile($file) {
2117                 $this->allParsedFiles[realpath($file)] = filemtime($file);
2118         }
2119
2120         /**
2121          * Uses the current value of $this->count to show line and line number
2122          */
2123         public function throwError($msg = null) {
2124                 if ($this->sourceLoc >= 0) {
2125                         $this->sourceParser->throwError($msg, $this->sourceLoc);
2126                 }
2127                 throw new exception($msg);
2128         }
2129
2130         // compile file $in to file $out if $in is newer than $out
2131         // returns true when it compiles, false otherwise
2132         public static function ccompile($in, $out, $less = null) {
2133                 if ($less === null) {
2134                         $less = new self;
2135                 }
2136                 return $less->checkedCompile($in, $out);
2137         }
2138
2139         public static function cexecute($in, $force = false, $less = null) {
2140                 if ($less === null) {
2141                         $less = new self;
2142                 }
2143                 return $less->cachedCompile($in, $force);
2144         }
2145
2146         static protected $cssColors = array(
2147                 'aliceblue' => '240,248,255',
2148                 'antiquewhite' => '250,235,215',
2149                 'aqua' => '0,255,255',
2150                 'aquamarine' => '127,255,212',
2151                 'azure' => '240,255,255',
2152                 'beige' => '245,245,220',
2153                 'bisque' => '255,228,196',
2154                 'black' => '0,0,0',
2155                 'blanchedalmond' => '255,235,205',
2156                 'blue' => '0,0,255',
2157                 'blueviolet' => '138,43,226',
2158                 'brown' => '165,42,42',
2159                 'burlywood' => '222,184,135',
2160                 'cadetblue' => '95,158,160',
2161                 'chartreuse' => '127,255,0',
2162                 'chocolate' => '210,105,30',
2163                 'coral' => '255,127,80',
2164                 'cornflowerblue' => '100,149,237',
2165                 'cornsilk' => '255,248,220',
2166                 'crimson' => '220,20,60',
2167                 'cyan' => '0,255,255',
2168                 'darkblue' => '0,0,139',
2169                 'darkcyan' => '0,139,139',
2170                 'darkgoldenrod' => '184,134,11',
2171                 'darkgray' => '169,169,169',
2172                 'darkgreen' => '0,100,0',
2173                 'darkgrey' => '169,169,169',
2174                 'darkkhaki' => '189,183,107',
2175                 'darkmagenta' => '139,0,139',
2176                 'darkolivegreen' => '85,107,47',
2177                 'darkorange' => '255,140,0',
2178                 'darkorchid' => '153,50,204',
2179                 'darkred' => '139,0,0',
2180                 'darksalmon' => '233,150,122',
2181                 'darkseagreen' => '143,188,143',
2182                 'darkslateblue' => '72,61,139',
2183                 'darkslategray' => '47,79,79',
2184                 'darkslategrey' => '47,79,79',
2185                 'darkturquoise' => '0,206,209',
2186                 'darkviolet' => '148,0,211',
2187                 'deeppink' => '255,20,147',
2188                 'deepskyblue' => '0,191,255',
2189                 'dimgray' => '105,105,105',
2190                 'dimgrey' => '105,105,105',
2191                 'dodgerblue' => '30,144,255',
2192                 'firebrick' => '178,34,34',
2193                 'floralwhite' => '255,250,240',
2194                 'forestgreen' => '34,139,34',
2195                 'fuchsia' => '255,0,255',
2196                 'gainsboro' => '220,220,220',
2197                 'ghostwhite' => '248,248,255',
2198                 'gold' => '255,215,0',
2199                 'goldenrod' => '218,165,32',
2200                 'gray' => '128,128,128',
2201                 'green' => '0,128,0',
2202                 'greenyellow' => '173,255,47',
2203                 'grey' => '128,128,128',
2204                 'honeydew' => '240,255,240',
2205                 'hotpink' => '255,105,180',
2206                 'indianred' => '205,92,92',
2207                 'indigo' => '75,0,130',
2208                 'ivory' => '255,255,240',
2209                 'khaki' => '240,230,140',
2210                 'lavender' => '230,230,250',
2211                 'lavenderblush' => '255,240,245',
2212                 'lawngreen' => '124,252,0',
2213                 'lemonchiffon' => '255,250,205',
2214                 'lightblue' => '173,216,230',
2215                 'lightcoral' => '240,128,128',
2216                 'lightcyan' => '224,255,255',
2217                 'lightgoldenrodyellow' => '250,250,210',
2218                 'lightgray' => '211,211,211',
2219                 'lightgreen' => '144,238,144',
2220                 'lightgrey' => '211,211,211',
2221                 'lightpink' => '255,182,193',
2222                 'lightsalmon' => '255,160,122',
2223                 'lightseagreen' => '32,178,170',
2224                 'lightskyblue' => '135,206,250',
2225                 'lightslategray' => '119,136,153',
2226                 'lightslategrey' => '119,136,153',
2227                 'lightsteelblue' => '176,196,222',
2228                 'lightyellow' => '255,255,224',
2229                 'lime' => '0,255,0',
2230                 'limegreen' => '50,205,50',
2231                 'linen' => '250,240,230',
2232                 'magenta' => '255,0,255',
2233                 'maroon' => '128,0,0',
2234                 'mediumaquamarine' => '102,205,170',
2235                 'mediumblue' => '0,0,205',
2236                 'mediumorchid' => '186,85,211',
2237                 'mediumpurple' => '147,112,219',
2238                 'mediumseagreen' => '60,179,113',
2239                 'mediumslateblue' => '123,104,238',
2240                 'mediumspringgreen' => '0,250,154',
2241                 'mediumturquoise' => '72,209,204',
2242                 'mediumvioletred' => '199,21,133',
2243                 'midnightblue' => '25,25,112',
2244                 'mintcream' => '245,255,250',
2245                 'mistyrose' => '255,228,225',
2246                 'moccasin' => '255,228,181',
2247                 'navajowhite' => '255,222,173',
2248                 'navy' => '0,0,128',
2249                 'oldlace' => '253,245,230',
2250                 'olive' => '128,128,0',
2251                 'olivedrab' => '107,142,35',
2252                 'orange' => '255,165,0',
2253                 'orangered' => '255,69,0',
2254                 'orchid' => '218,112,214',
2255                 'palegoldenrod' => '238,232,170',
2256                 'palegreen' => '152,251,152',
2257                 'paleturquoise' => '175,238,238',
2258                 'palevioletred' => '219,112,147',
2259                 'papayawhip' => '255,239,213',
2260                 'peachpuff' => '255,218,185',
2261                 'peru' => '205,133,63',
2262                 'pink' => '255,192,203',
2263                 'plum' => '221,160,221',
2264                 'powderblue' => '176,224,230',
2265                 'purple' => '128,0,128',
2266                 'red' => '255,0,0',
2267                 'rosybrown' => '188,143,143',
2268                 'royalblue' => '65,105,225',
2269                 'saddlebrown' => '139,69,19',
2270                 'salmon' => '250,128,114',
2271                 'sandybrown' => '244,164,96',
2272                 'seagreen' => '46,139,87',
2273                 'seashell' => '255,245,238',
2274                 'sienna' => '160,82,45',
2275                 'silver' => '192,192,192',
2276                 'skyblue' => '135,206,235',
2277                 'slateblue' => '106,90,205',
2278                 'slategray' => '112,128,144',
2279                 'slategrey' => '112,128,144',
2280                 'snow' => '255,250,250',
2281                 'springgreen' => '0,255,127',
2282                 'steelblue' => '70,130,180',
2283                 'tan' => '210,180,140',
2284                 'teal' => '0,128,128',
2285                 'thistle' => '216,191,216',
2286                 'tomato' => '255,99,71',
2287                 'transparent' => '0,0,0,0',
2288                 'turquoise' => '64,224,208',
2289                 'violet' => '238,130,238',
2290                 'wheat' => '245,222,179',
2291                 'white' => '255,255,255',
2292                 'whitesmoke' => '245,245,245',
2293                 'yellow' => '255,255,0',
2294                 'yellowgreen' => '154,205,50'
2295         );
2296 }
2297
2298 // responsible for taking a string of LESS code and converting it into a
2299 // syntax tree
2300 class lessc_parser {
2301         static protected $nextBlockId = 0; // used to uniquely identify blocks
2302
2303         static protected $precedence = array(
2304                 '=<' => 0,
2305                 '>=' => 0,
2306                 '=' => 0,
2307                 '<' => 0,
2308                 '>' => 0,
2309
2310                 '+' => 1,
2311                 '-' => 1,
2312                 '*' => 2,
2313                 '/' => 2,
2314                 '%' => 2,
2315         );
2316
2317         static protected $whitePattern;
2318         static protected $commentMulti;
2319
2320         static protected $commentSingle = "//";
2321         static protected $commentMultiLeft = "/*";
2322         static protected $commentMultiRight = "*/";
2323
2324         // regex string to match any of the operators
2325         static protected $operatorString;
2326
2327         // these properties will supress division unless it's inside parenthases
2328         static protected $supressDivisionProps =
2329                 array('/border-radius$/i', '/^font$/i');
2330
2331         protected $blockDirectives = array("font-face", "keyframes", "page", "-moz-document", "viewport", "-moz-viewport", "-o-viewport", "-ms-viewport");
2332         protected $lineDirectives = array("charset");
2333
2334         /**
2335          * if we are in parens we can be more liberal with whitespace around
2336          * operators because it must evaluate to a single value and thus is less
2337          * ambiguous.
2338          *
2339          * Consider:
2340          *     property1: 10 -5; // is two numbers, 10 and -5
2341          *     property2: (10 -5); // should evaluate to 5
2342          */
2343         protected $inParens = false;
2344
2345         // caches preg escaped literals
2346         static protected $literalCache = array();
2347
2348         public function __construct($lessc, $sourceName = null) {
2349                 $this->eatWhiteDefault = true;
2350                 // reference to less needed for vPrefix, mPrefix, and parentSelector
2351                 $this->lessc = $lessc;
2352
2353                 $this->sourceName = $sourceName; // name used for error messages
2354
2355                 $this->writeComments = false;
2356
2357                 if (!self::$operatorString) {
2358                         self::$operatorString =
2359                                 '('.implode('|', array_map(array('lessc', 'preg_quote'),
2360                                         array_keys(self::$precedence))).')';
2361
2362                         $commentSingle = lessc::preg_quote(self::$commentSingle);
2363                         $commentMultiLeft = lessc::preg_quote(self::$commentMultiLeft);
2364                         $commentMultiRight = lessc::preg_quote(self::$commentMultiRight);
2365
2366                         self::$commentMulti = $commentMultiLeft.'.*?'.$commentMultiRight;
2367                         self::$whitePattern = '/'.$commentSingle.'[^\n]*\s*|('.self::$commentMulti.')\s*|\s+/Ais';
2368                 }
2369         }
2370
2371         public function parse($buffer) {
2372                 $this->count = 0;
2373                 $this->line = 1;
2374
2375                 $this->env = null; // block stack
2376                 $this->buffer = $this->writeComments ? $buffer : $this->removeComments($buffer);
2377                 $this->pushSpecialBlock("root");
2378                 $this->eatWhiteDefault = true;
2379                 $this->seenComments = array();
2380
2381                 // trim whitespace on head
2382                 // if (preg_match('/^\s+/', $this->buffer, $m)) {
2383                 //      $this->line += substr_count($m[0], "\n");
2384                 //      $this->buffer = ltrim($this->buffer);
2385                 // }
2386                 $this->whitespace();
2387
2388                 // parse the entire file
2389                 while (false !== $this->parseChunk());
2390
2391                 if ($this->count != strlen($this->buffer))
2392                         $this->throwError();
2393
2394                 // TODO report where the block was opened
2395                 if ( !property_exists($this->env, 'parent') || !is_null($this->env->parent) )
2396                         throw new exception('parse error: unclosed block');
2397
2398                 return $this->env;
2399         }
2400
2401         /**
2402          * Parse a single chunk off the head of the buffer and append it to the
2403          * current parse environment.
2404          * Returns false when the buffer is empty, or when there is an error.
2405          *
2406          * This function is called repeatedly until the entire document is
2407          * parsed.
2408          *
2409          * This parser is most similar to a recursive descent parser. Single
2410          * functions represent discrete grammatical rules for the language, and
2411          * they are able to capture the text that represents those rules.
2412          *
2413          * Consider the function lessc::keyword(). (all parse functions are
2414          * structured the same)
2415          *
2416          * The function takes a single reference argument. When calling the
2417          * function it will attempt to match a keyword on the head of the buffer.
2418          * If it is successful, it will place the keyword in the referenced
2419          * argument, advance the position in the buffer, and return true. If it
2420          * fails then it won't advance the buffer and it will return false.
2421          *
2422          * All of these parse functions are powered by lessc::match(), which behaves
2423          * the same way, but takes a literal regular expression. Sometimes it is
2424          * more convenient to use match instead of creating a new function.
2425          *
2426          * Because of the format of the functions, to parse an entire string of
2427          * grammatical rules, you can chain them together using &&.
2428          *
2429          * But, if some of the rules in the chain succeed before one fails, then
2430          * the buffer position will be left at an invalid state. In order to
2431          * avoid this, lessc::seek() is used to remember and set buffer positions.
2432          *
2433          * Before parsing a chain, use $s = $this->seek() to remember the current
2434          * position into $s. Then if a chain fails, use $this->seek($s) to
2435          * go back where we started.
2436          */
2437         protected function parseChunk() {
2438                 if (empty($this->buffer)) return false;
2439                 $s = $this->seek();
2440
2441                 if ($this->whitespace()) {
2442                         return true;
2443                 }
2444
2445                 // setting a property
2446                 if ($this->keyword($key) && $this->assign() &&
2447                         $this->propertyValue($value, $key) && $this->end())
2448                 {
2449                         $this->append(array('assign', $key, $value), $s);
2450                         return true;
2451                 } else {
2452                         $this->seek($s);
2453                 }
2454
2455
2456                 // look for special css blocks
2457                 if ($this->literal('@', false)) {
2458                         $this->count--;
2459
2460                         // media
2461                         if ($this->literal('@media')) {
2462                                 if (($this->mediaQueryList($mediaQueries) || true)
2463                                         && $this->literal('{'))
2464                                 {
2465                                         $media = $this->pushSpecialBlock("media");
2466                                         $media->queries = is_null($mediaQueries) ? array() : $mediaQueries;
2467                                         return true;
2468                                 } else {
2469                                         $this->seek($s);
2470                                         return false;
2471                                 }
2472                         }
2473
2474                         if ($this->literal("@", false) && $this->keyword($dirName)) {
2475                                 if ($this->isDirective($dirName, $this->blockDirectives)) {
2476                                         if (($this->openString("{", $dirValue, null, array(";")) || true) &&
2477                                                 $this->literal("{"))
2478                                         {
2479                                                 $dir = $this->pushSpecialBlock("directive");
2480                                                 $dir->name = $dirName;
2481                                                 if (isset($dirValue)) $dir->value = $dirValue;
2482                                                 return true;
2483                                         }
2484                                 } elseif ($this->isDirective($dirName, $this->lineDirectives)) {
2485                                         if ($this->propertyValue($dirValue) && $this->end()) {
2486                                                 $this->append(array("directive", $dirName, $dirValue));
2487                                                 return true;
2488                                         }
2489                                 }
2490                         }
2491
2492                         $this->seek($s);
2493                 }
2494
2495                 // setting a variable
2496                 if ($this->variable($var) && $this->assign() &&
2497                         $this->propertyValue($value) && $this->end())
2498                 {
2499                         $this->append(array('assign', $var, $value), $s);
2500                         return true;
2501                 } else {
2502                         $this->seek($s);
2503                 }
2504
2505                 if ($this->import($importValue)) {
2506                         $this->append($importValue, $s);
2507                         return true;
2508                 }
2509
2510                 // opening parametric mixin
2511                 if ($this->tag($tag, true) && $this->argumentDef($args, $isVararg) &&
2512                         ($this->guards($guards) || true) &&
2513                         $this->literal('{'))
2514                 {
2515                         $block = $this->pushBlock($this->fixTags(array($tag)));
2516                         $block->args = $args;
2517                         $block->isVararg = $isVararg;
2518                         if (!empty($guards)) $block->guards = $guards;
2519                         return true;
2520                 } else {
2521                         $this->seek($s);
2522                 }
2523
2524                 // opening a simple block
2525                 if ($this->tags($tags) && $this->literal('{', false)) {
2526                         $tags = $this->fixTags($tags);
2527                         $this->pushBlock($tags);
2528                         return true;
2529                 } else {
2530                         $this->seek($s);
2531                 }
2532
2533                 // closing a block
2534                 if ($this->literal('}', false)) {
2535                         try {
2536                                 $block = $this->pop();
2537                         } catch (exception $e) {
2538                                 $this->seek($s);
2539                                 $this->throwError($e->getMessage());
2540                         }
2541
2542                         $hidden = false;
2543                         if (is_null($block->type)) {
2544                                 $hidden = true;
2545                                 if (!isset($block->args)) {
2546                                         foreach ($block->tags as $tag) {
2547                                                 if (!is_string($tag) || $tag{0} != $this->lessc->mPrefix) {
2548                                                         $hidden = false;
2549                                                         break;
2550                                                 }
2551                                         }
2552                                 }
2553
2554                                 foreach ($block->tags as $tag) {
2555                                         if (is_string($tag)) {
2556                                                 $this->env->children[$tag][] = $block;
2557                                         }
2558                                 }
2559                         }
2560
2561                         if (!$hidden) {
2562                                 $this->append(array('block', $block), $s);
2563                         }
2564
2565                         // this is done here so comments aren't bundled into he block that
2566                         // was just closed
2567                         $this->whitespace();
2568                         return true;
2569                 }
2570
2571                 // mixin
2572                 if ($this->mixinTags($tags) &&
2573                         ($this->argumentDef($argv, $isVararg) || true) &&
2574                         ($this->keyword($suffix) || true) && $this->end())
2575                 {
2576                         $tags = $this->fixTags($tags);
2577                         $this->append(array('mixin', $tags, $argv, $suffix), $s);
2578                         return true;
2579                 } else {
2580                         $this->seek($s);
2581                 }
2582
2583                 // spare ;
2584                 if ($this->literal(';')) return true;
2585
2586                 return false; // got nothing, throw error
2587         }
2588
2589         protected function isDirective($dirname, $directives) {
2590                 // TODO: cache pattern in parser
2591                 $pattern = implode("|",
2592                         array_map(array("lessc", "preg_quote"), $directives));
2593                 $pattern = '/^(-[a-z-]+-)?(' . $pattern . ')$/i';
2594
2595                 return preg_match($pattern, $dirname);
2596         }
2597
2598         protected function fixTags($tags) {
2599                 // move @ tags out of variable namespace
2600                 foreach ($tags as &$tag) {
2601                         if ($tag{0} == $this->lessc->vPrefix)
2602                                 $tag[0] = $this->lessc->mPrefix;
2603                 }
2604                 return $tags;
2605         }
2606
2607         // a list of expressions
2608         protected function expressionList(&$exps) {
2609                 $values = array();
2610
2611                 while ($this->expression($exp)) {
2612                         $values[] = $exp;
2613                 }
2614
2615                 if (count($values) == 0) return false;
2616
2617                 $exps = lessc::compressList($values, ' ');
2618                 return true;
2619         }
2620
2621         /**
2622          * Attempt to consume an expression.
2623          * @link http://en.wikipedia.org/wiki/Operator-precedence_parser#Pseudo-code
2624          */
2625         protected function expression(&$out) {
2626                 if ($this->value($lhs)) {
2627                         $out = $this->expHelper($lhs, 0);
2628
2629                         // look for / shorthand
2630                         if (!empty($this->env->supressedDivision)) {
2631                                 unset($this->env->supressedDivision);
2632                                 $s = $this->seek();
2633                                 if ($this->literal("/") && $this->value($rhs)) {
2634                                         $out = array("list", "",
2635                                                 array($out, array("keyword", "/"), $rhs));
2636                                 } else {
2637                                         $this->seek($s);
2638                                 }
2639                         }
2640
2641                         return true;
2642                 }
2643                 return false;
2644         }
2645
2646         /**
2647          * recursively parse infix equation with $lhs at precedence $minP
2648          */
2649         protected function expHelper($lhs, $minP) {
2650                 $this->inExp = true;
2651                 $ss = $this->seek();
2652
2653                 while (true) {
2654                         $whiteBefore = isset($this->buffer[$this->count - 1]) &&
2655                                 ctype_space($this->buffer[$this->count - 1]);
2656
2657                         // If there is whitespace before the operator, then we require
2658                         // whitespace after the operator for it to be an expression
2659                         $needWhite = $whiteBefore && !$this->inParens;
2660
2661                         if ($this->match(self::$operatorString.($needWhite ? '\s' : ''), $m) && self::$precedence[$m[1]] >= $minP) {
2662                                 if (!$this->inParens && isset($this->env->currentProperty) && $m[1] == "/" && empty($this->env->supressedDivision)) {
2663                                         foreach (self::$supressDivisionProps as $pattern) {
2664                                                 if (preg_match($pattern, $this->env->currentProperty)) {
2665                                                         $this->env->supressedDivision = true;
2666                                                         break 2;
2667                                                 }
2668                                         }
2669                                 }
2670
2671
2672                                 $whiteAfter = isset($this->buffer[$this->count - 1]) &&
2673                                         ctype_space($this->buffer[$this->count - 1]);
2674
2675                                 if (!$this->value($rhs)) break;
2676
2677                                 // peek for next operator to see what to do with rhs
2678                                 if ($this->peek(self::$operatorString, $next) && self::$precedence[$next[1]] > self::$precedence[$m[1]]) {
2679                                         $rhs = $this->expHelper($rhs, self::$precedence[$next[1]]);
2680                                 }
2681
2682                                 $lhs = array('expression', $m[1], $lhs, $rhs, $whiteBefore, $whiteAfter);
2683                                 $ss = $this->seek();
2684
2685                                 continue;
2686                         }
2687
2688                         break;
2689                 }
2690
2691                 $this->seek($ss);
2692
2693                 return $lhs;
2694         }
2695
2696         // consume a list of values for a property
2697         public function propertyValue(&$value, $keyName = null) {
2698                 $values = array();
2699
2700                 if ($keyName !== null) $this->env->currentProperty = $keyName;
2701
2702                 $s = null;
2703                 while ($this->expressionList($v)) {
2704                         $values[] = $v;
2705                         $s = $this->seek();
2706                         if (!$this->literal(',')) break;
2707                 }
2708
2709                 if ($s) $this->seek($s);
2710
2711                 if ($keyName !== null) unset($this->env->currentProperty);
2712
2713                 if (count($values) == 0) return false;
2714
2715                 $value = lessc::compressList($values, ', ');
2716                 return true;
2717         }
2718
2719         protected function parenValue(&$out) {
2720                 $s = $this->seek();
2721
2722                 // speed shortcut
2723                 if (isset($this->buffer[$this->count]) && $this->buffer[$this->count] != "(") {
2724                         return false;
2725                 }
2726
2727                 $inParens = $this->inParens;
2728                 if ($this->literal("(") &&
2729                         ($this->inParens = true) && $this->expression($exp) &&
2730                         $this->literal(")"))
2731                 {
2732                         $out = $exp;
2733                         $this->inParens = $inParens;
2734                         return true;
2735                 } else {
2736                         $this->inParens = $inParens;
2737                         $this->seek($s);
2738                 }
2739
2740                 return false;
2741         }
2742
2743         // a single value
2744         protected function value(&$value) {
2745                 $s = $this->seek();
2746
2747                 // speed shortcut
2748                 if (isset($this->buffer[$this->count]) && $this->buffer[$this->count] == "-") {
2749                         // negation
2750                         if ($this->literal("-", false) &&
2751                                 (($this->variable($inner) && $inner = array("variable", $inner)) ||
2752                                 $this->unit($inner) ||
2753                                 $this->parenValue($inner)))
2754                         {
2755                                 $value = array("unary", "-", $inner);
2756                                 return true;
2757                         } else {
2758                                 $this->seek($s);
2759                         }
2760                 }
2761
2762                 if ($this->parenValue($value)) return true;
2763                 if ($this->unit($value)) return true;
2764                 if ($this->color($value)) return true;
2765                 if ($this->func($value)) return true;
2766                 if ($this->string($value)) return true;
2767
2768                 if ($this->keyword($word)) {
2769                         $value = array('keyword', $word);
2770                         return true;
2771                 }
2772
2773                 // try a variable
2774                 if ($this->variable($var)) {
2775                         $value = array('variable', $var);
2776                         return true;
2777                 }
2778
2779                 // unquote string (should this work on any type?
2780                 if ($this->literal("~") && $this->string($str)) {
2781                         $value = array("escape", $str);
2782                         return true;
2783                 } else {
2784                         $this->seek($s);
2785                 }
2786
2787                 // css hack: \0
2788                 if ($this->literal('\\') && $this->match('([0-9]+)', $m)) {
2789                         $value = array('keyword', '\\'.$m[1]);
2790                         return true;
2791                 } else {
2792                         $this->seek($s);
2793                 }
2794
2795                 return false;
2796         }
2797
2798         // an import statement
2799         protected function import(&$out) {
2800                 if (!$this->literal('@import')) return false;
2801
2802                 // @import "something.css" media;
2803                 // @import url("something.css") media;
2804                 // @import url(something.css) media;
2805
2806                 if ($this->propertyValue($value)) {
2807                         $out = array("import", $value);
2808                         return true;
2809                 }
2810         }
2811
2812         protected function mediaQueryList(&$out) {
2813                 if ($this->genericList($list, "mediaQuery", ",", false)) {
2814                         $out = $list[2];
2815                         return true;
2816                 }
2817                 return false;
2818         }
2819
2820         protected function mediaQuery(&$out) {
2821                 $s = $this->seek();
2822
2823                 $expressions = null;
2824                 $parts = array();
2825
2826                 if (($this->literal("only") && ($only = true) || $this->literal("not") && ($not = true) || true) && $this->keyword($mediaType)) {
2827                         $prop = array("mediaType");
2828                         if (isset($only)) $prop[] = "only";
2829                         if (isset($not)) $prop[] = "not";
2830                         $prop[] = $mediaType;
2831                         $parts[] = $prop;
2832                 } else {
2833                         $this->seek($s);
2834                 }
2835
2836
2837                 if (!empty($mediaType) && !$this->literal("and")) {
2838                         // ~
2839                 } else {
2840                         $this->genericList($expressions, "mediaExpression", "and", false);
2841                         if (is_array($expressions)) $parts = array_merge($parts, $expressions[2]);
2842                 }
2843
2844                 if (count($parts) == 0) {
2845                         $this->seek($s);
2846                         return false;
2847                 }
2848
2849                 $out = $parts;
2850                 return true;
2851         }
2852
2853         protected function mediaExpression(&$out) {
2854                 $s = $this->seek();
2855                 $value = null;
2856                 if ($this->literal("(") &&
2857                         $this->keyword($feature) &&
2858                         ($this->literal(":") && $this->expression($value) || true) &&
2859                         $this->literal(")"))
2860                 {
2861                         $out = array("mediaExp", $feature);
2862                         if ($value) $out[] = $value;
2863                         return true;
2864                 } elseif ($this->variable($variable)) {
2865                         $out = array('variable', $variable);
2866                         return true;
2867                 }
2868
2869                 $this->seek($s);
2870                 return false;
2871         }
2872
2873         // an unbounded string stopped by $end
2874         protected function openString($end, &$out, $nestingOpen=null, $rejectStrs = null) {
2875                 $oldWhite = $this->eatWhiteDefault;
2876                 $this->eatWhiteDefault = false;
2877
2878                 $stop = array("'", '"', "@{", $end);
2879                 $stop = array_map(array("lessc", "preg_quote"), $stop);
2880                 // $stop[] = self::$commentMulti;
2881
2882                 if (!is_null($rejectStrs)) {
2883                         $stop = array_merge($stop, $rejectStrs);
2884                 }
2885
2886                 $patt = '(.*?)('.implode("|", $stop).')';
2887
2888                 $nestingLevel = 0;
2889
2890                 $content = array();
2891                 while ($this->match($patt, $m, false)) {
2892                         if (!empty($m[1])) {
2893                                 $content[] = $m[1];
2894                                 if ($nestingOpen) {
2895                                         $nestingLevel += substr_count($m[1], $nestingOpen);
2896                                 }
2897                         }
2898
2899                         $tok = $m[2];
2900
2901                         $this->count-= strlen($tok);
2902                         if ($tok == $end) {
2903                                 if ($nestingLevel == 0) {
2904                                         break;
2905                                 } else {
2906                                         $nestingLevel--;
2907                                 }
2908                         }
2909
2910                         if (($tok == "'" || $tok == '"') && $this->string($str)) {
2911                                 $content[] = $str;
2912                                 continue;
2913                         }
2914
2915                         if ($tok == "@{" && $this->interpolation($inter)) {
2916                                 $content[] = $inter;
2917                                 continue;
2918                         }
2919
2920                         if (!empty($rejectStrs) && in_array($tok, $rejectStrs)) {
2921                                 break;
2922                         }
2923
2924                         $content[] = $tok;
2925                         $this->count+= strlen($tok);
2926                 }
2927
2928                 $this->eatWhiteDefault = $oldWhite;
2929
2930                 if (count($content) == 0) return false;
2931
2932                 // trim the end
2933                 if (is_string(end($content))) {
2934                         $content[count($content) - 1] = rtrim(end($content));
2935                 }
2936
2937                 $out = array("string", "", $content);
2938                 return true;
2939         }
2940
2941         protected function string(&$out) {
2942                 $s = $this->seek();
2943                 if ($this->literal('"', false)) {
2944                         $delim = '"';
2945                 } elseif ($this->literal("'", false)) {
2946                         $delim = "'";
2947                 } else {
2948                         return false;
2949                 }
2950
2951                 $content = array();
2952
2953                 // look for either ending delim , escape, or string interpolation
2954                 $patt = '([^\n]*?)(@\{|\\\\|' .
2955                         lessc::preg_quote($delim).')';
2956
2957                 $oldWhite = $this->eatWhiteDefault;
2958                 $this->eatWhiteDefault = false;
2959
2960                 while ($this->match($patt, $m, false)) {
2961                         $content[] = $m[1];
2962                         if ($m[2] == "@{") {
2963                                 $this->count -= strlen($m[2]);
2964                                 if ($this->interpolation($inter, false)) {
2965                                         $content[] = $inter;
2966                                 } else {
2967                                         $this->count += strlen($m[2]);
2968                                         $content[] = "@{"; // ignore it
2969                                 }
2970                         } elseif ($m[2] == '\\') {
2971                                 $content[] = $m[2];
2972                                 if ($this->literal($delim, false)) {
2973                                         $content[] = $delim;
2974                                 }
2975                         } else {
2976                                 $this->count -= strlen($delim);
2977                                 break; // delim
2978                         }
2979                 }
2980
2981                 $this->eatWhiteDefault = $oldWhite;
2982
2983                 if ($this->literal($delim)) {
2984                         $out = array("string", $delim, $content);
2985                         return true;
2986                 }
2987
2988                 $this->seek($s);
2989                 return false;
2990         }
2991
2992         protected function interpolation(&$out) {
2993                 $oldWhite = $this->eatWhiteDefault;
2994                 $this->eatWhiteDefault = true;
2995
2996                 $s = $this->seek();
2997                 if ($this->literal("@{") &&
2998                         $this->openString("}", $interp, null, array("'", '"', ";")) &&
2999                         $this->literal("}", false))
3000                 {
3001                         $out = array("interpolate", $interp);
3002                         $this->eatWhiteDefault = $oldWhite;
3003                         if ($this->eatWhiteDefault) $this->whitespace();
3004                         return true;
3005                 }
3006
3007                 $this->eatWhiteDefault = $oldWhite;
3008                 $this->seek($s);
3009                 return false;
3010         }
3011
3012         protected function unit(&$unit) {
3013                 // speed shortcut
3014                 if (isset($this->buffer[$this->count])) {
3015                         $char = $this->buffer[$this->count];
3016                         if (!ctype_digit($char) && $char != ".") return false;
3017                 }
3018
3019                 if ($this->match('([0-9]+(?:\.[0-9]*)?|\.[0-9]+)([%a-zA-Z]+)?', $m)) {
3020                         $unit = array("number", $m[1], empty($m[2]) ? "" : $m[2]);
3021                         return true;
3022                 }
3023                 return false;
3024         }
3025
3026         // a # color
3027         protected function color(&$out) {
3028                 if ($this->match('(#(?:[0-9a-f]{8}|[0-9a-f]{6}|[0-9a-f]{3}))', $m)) {
3029                         if (strlen($m[1]) > 7) {
3030                                 $out = array("string", "", array($m[1]));
3031                         } else {
3032                                 $out = array("raw_color", $m[1]);
3033                         }
3034                         return true;
3035                 }
3036
3037                 return false;
3038         }
3039
3040         // consume an argument definition list surrounded by ()
3041         // each argument is a variable name with optional value
3042         // or at the end a ... or a variable named followed by ...
3043         // arguments are separated by , unless a ; is in the list, then ; is the
3044         // delimiter.
3045         protected function argumentDef(&$args, &$isVararg) {
3046                 $s = $this->seek();
3047                 if (!$this->literal('(')) return false;
3048
3049                 $values = array();
3050                 $delim = ",";
3051                 $method = "expressionList";
3052
3053                 $isVararg = false;
3054                 while (true) {
3055                         if ($this->literal("...")) {
3056                                 $isVararg = true;
3057                                 break;
3058                         }
3059
3060                         if ($this->$method($value)) {
3061                                 if ($value[0] == "variable") {
3062                                         $arg = array("arg", $value[1]);
3063                                         $ss = $this->seek();
3064
3065                                         if ($this->assign() && $this->$method($rhs)) {
3066                                                 $arg[] = $rhs;
3067                                         } else {
3068                                                 $this->seek($ss);
3069                                                 if ($this->literal("...")) {
3070                                                         $arg[0] = "rest";
3071                                                         $isVararg = true;
3072                                                 }
3073                                         }
3074
3075                                         $values[] = $arg;
3076                                         if ($isVararg) break;
3077                                         continue;
3078                                 } else {
3079                                         $values[] = array("lit", $value);
3080                                 }
3081                         }
3082
3083
3084                         if (!$this->literal($delim)) {
3085                                 if ($delim == "," && $this->literal(";")) {
3086                                         // found new delim, convert existing args
3087                                         $delim = ";";
3088                                         $method = "propertyValue";
3089
3090                                         // transform arg list
3091                                         if (isset($values[1])) { // 2 items
3092                                                 $newList = array();
3093                                                 foreach ($values as $i => $arg) {
3094                                                         switch($arg[0]) {
3095                                                         case "arg":
3096                                                                 if ($i) {
3097                                                                         $this->throwError("Cannot mix ; and , as delimiter types");
3098                                                                 }
3099                                                                 $newList[] = $arg[2];
3100                                                                 break;
3101                                                         case "lit":
3102                                                                 $newList[] = $arg[1];
3103                                                                 break;
3104                                                         case "rest":
3105                                                                 $this->throwError("Unexpected rest before semicolon");
3106                                                         }
3107                                                 }
3108
3109                                                 $newList = array("list", ", ", $newList);
3110
3111                                                 switch ($values[0][0]) {
3112                                                 case "arg":
3113                                                         $newArg = array("arg", $values[0][1], $newList);
3114                                                         break;
3115                                                 case "lit":
3116                                                         $newArg = array("lit", $newList);
3117                                                         break;
3118                                                 }
3119
3120                                         } elseif ($values) { // 1 item
3121                                                 $newArg = $values[0];
3122                                         }
3123
3124                                         if ($newArg) {
3125                                                 $values = array($newArg);
3126                                         }
3127                                 } else {
3128                                         break;
3129                                 }
3130                         }
3131                 }
3132
3133                 if (!$this->literal(')')) {
3134                         $this->seek($s);
3135                         return false;
3136                 }
3137
3138                 $args = $values;
3139
3140                 return true;
3141         }
3142
3143         // consume a list of tags
3144         // this accepts a hanging delimiter
3145         protected function tags(&$tags, $simple = false, $delim = ',') {
3146                 $tags = array();
3147                 while ($this->tag($tt, $simple)) {
3148                         $tags[] = $tt;
3149                         if (!$this->literal($delim)) break;
3150                 }
3151                 if (count($tags) == 0) return false;
3152
3153                 return true;
3154         }
3155
3156         // list of tags of specifying mixin path
3157         // optionally separated by > (lazy, accepts extra >)
3158         protected function mixinTags(&$tags) {
3159                 $tags = array();
3160                 while ($this->tag($tt, true)) {
3161                         $tags[] = $tt;
3162                         $this->literal(">");
3163                 }
3164
3165                 if (count($tags) == 0) return false;
3166
3167                 return true;
3168         }
3169
3170         // a bracketed value (contained within in a tag definition)
3171         protected function tagBracket(&$parts, &$hasExpression) {
3172                 // speed shortcut
3173                 if (isset($this->buffer[$this->count]) && $this->buffer[$this->count] != "[") {
3174                         return false;
3175                 }
3176
3177                 $s = $this->seek();
3178
3179                 $hasInterpolation = false;
3180
3181                 if ($this->literal("[", false)) {
3182                         $attrParts = array("[");
3183                         // keyword, string, operator
3184                         while (true) {
3185                                 if ($this->literal("]", false)) {
3186                                         $this->count--;
3187                                         break; // get out early
3188                                 }
3189
3190                                 if ($this->match('\s+', $m)) {
3191                                         $attrParts[] = " ";
3192                                         continue;
3193                                 }
3194                                 if ($this->string($str)) {
3195                                         // escape parent selector, (yuck)
3196                                         foreach ($str[2] as &$chunk) {
3197                                                 $chunk = str_replace($this->lessc->parentSelector, "$&$", $chunk);
3198                                         }
3199
3200                                         $attrParts[] = $str;
3201                                         $hasInterpolation = true;
3202                                         continue;
3203                                 }
3204
3205                                 if ($this->keyword($word)) {
3206                                         $attrParts[] = $word;
3207                                         continue;
3208                                 }
3209
3210                                 if ($this->interpolation($inter, false)) {
3211                                         $attrParts[] = $inter;
3212                                         $hasInterpolation = true;
3213                                         continue;
3214                                 }
3215
3216                                 // operator, handles attr namespace too
3217                                 if ($this->match('[|-~\$\*\^=]+', $m)) {
3218                                         $attrParts[] = $m[0];
3219                                         continue;
3220                                 }
3221
3222                                 break;
3223                         }
3224
3225                         if ($this->literal("]", false)) {
3226                                 $attrParts[] = "]";
3227                                 foreach ($attrParts as $part) {
3228                                         $parts[] = $part;
3229                                 }
3230                                 $hasExpression = $hasExpression || $hasInterpolation;
3231                                 return true;
3232                         }
3233                         $this->seek($s);
3234                 }
3235
3236                 $this->seek($s);
3237                 return false;
3238         }
3239
3240         // a space separated list of selectors
3241         protected function tag(&$tag, $simple = false) {
3242                 if ($simple)
3243                         $chars = '^@,:;{}\][>\(\) "\'';
3244                 else
3245                         $chars = '^@,;{}["\'';
3246
3247                 $s = $this->seek();
3248
3249                 $hasExpression = false;
3250                 $parts = array();
3251                 while ($this->tagBracket($parts, $hasExpression));
3252
3253                 $oldWhite = $this->eatWhiteDefault;
3254                 $this->eatWhiteDefault = false;
3255
3256                 while (true) {
3257                         if ($this->match('(['.$chars.'0-9]['.$chars.']*)', $m)) {
3258                                 $parts[] = $m[1];
3259                                 if ($simple) break;
3260
3261                                 while ($this->tagBracket($parts, $hasExpression));
3262                                 continue;
3263                         }
3264
3265                         if (isset($this->buffer[$this->count]) && $this->buffer[$this->count] == "@") {
3266                                 if ($this->interpolation($interp)) {
3267                                         $hasExpression = true;
3268                                         $interp[2] = true; // don't unescape
3269                                         $parts[] = $interp;
3270                                         continue;
3271                                 }
3272
3273                                 if ($this->literal("@")) {
3274                                         $parts[] = "@";
3275                                         continue;
3276                                 }
3277                         }
3278
3279                         if ($this->unit($unit)) { // for keyframes
3280                                 $parts[] = $unit[1];
3281                                 $parts[] = $unit[2];
3282                                 continue;
3283                         }
3284
3285                         break;
3286                 }
3287
3288                 $this->eatWhiteDefault = $oldWhite;
3289                 if (!$parts) {
3290                         $this->seek($s);
3291                         return false;
3292                 }
3293
3294                 if ($hasExpression) {
3295                         $tag = array("exp", array("string", "", $parts));
3296                 } else {
3297                         $tag = trim(implode($parts));
3298                 }
3299
3300                 $this->whitespace();
3301                 return true;
3302         }
3303
3304         // a css function
3305         protected function func(&$func) {
3306                 $s = $this->seek();
3307
3308                 if ($this->match('(%|[\w\-_][\w\-_:\.]+|[\w_])', $m) && $this->literal('(')) {
3309                         $fname = $m[1];
3310
3311                         $sPreArgs = $this->seek();
3312
3313                         $args = array();
3314                         while (true) {
3315                                 $ss = $this->seek();
3316                                 // this ugly nonsense is for ie filter properties
3317                                 if ($this->keyword($name) && $this->literal('=') && $this->expressionList($value)) {
3318                                         $args[] = array("string", "", array($name, "=", $value));
3319                                 } else {
3320                                         $this->seek($ss);
3321                                         if ($this->expressionList($value)) {
3322                                                 $args[] = $value;
3323                                         }
3324                                 }
3325
3326                                 if (!$this->literal(',')) break;
3327                         }
3328                         $args = array('list', ',', $args);
3329
3330                         if ($this->literal(')')) {
3331                                 $func = array('function', $fname, $args);
3332                                 return true;
3333                         } elseif ($fname == 'url') {
3334                                 // couldn't parse and in url? treat as string
3335                                 $this->seek($sPreArgs);
3336                                 if ($this->openString(")", $string) && $this->literal(")")) {
3337                                         $func = array('function', $fname, $string);
3338                                         return true;
3339                                 }
3340                         }
3341                 }
3342
3343                 $this->seek($s);
3344                 return false;
3345         }
3346
3347         // consume a less variable
3348         protected function variable(&$name) {
3349                 $s = $this->seek();
3350                 if ($this->literal($this->lessc->vPrefix, false) &&
3351                         ($this->variable($sub) || $this->keyword($name)))
3352                 {
3353                         if (!empty($sub)) {
3354                                 $name = array('variable', $sub);
3355                         } else {
3356                                 $name = $this->lessc->vPrefix.$name;
3357                         }
3358                         return true;
3359                 }
3360
3361                 $name = null;
3362                 $this->seek($s);
3363                 return false;
3364         }
3365
3366         /**
3367          * Consume an assignment operator
3368          * Can optionally take a name that will be set to the current property name
3369          */
3370         protected function assign($name = null) {
3371                 if ($name) $this->currentProperty = $name;
3372                 return $this->literal(':') || $this->literal('=');
3373         }
3374
3375         // consume a keyword
3376         protected function keyword(&$word) {
3377                 if ($this->match('([\w_\-\*!"][\w\-_"]*)', $m)) {
3378                         $word = $m[1];
3379                         return true;
3380                 }
3381                 return false;
3382         }
3383
3384         // consume an end of statement delimiter
3385         protected function end() {
3386                 if ($this->literal(';', false)) {
3387                         return true;
3388                 } elseif ($this->count == strlen($this->buffer) || $this->buffer[$this->count] == '}') {
3389                         // if there is end of file or a closing block next then we don't need a ;
3390                         return true;
3391                 }
3392                 return false;
3393         }
3394
3395         protected function guards(&$guards) {
3396                 $s = $this->seek();
3397
3398                 if (!$this->literal("when")) {
3399                         $this->seek($s);
3400                         return false;
3401                 }
3402
3403                 $guards = array();
3404
3405                 while ($this->guardGroup($g)) {
3406                         $guards[] = $g;
3407                         if (!$this->literal(",")) break;
3408                 }
3409
3410                 if (count($guards) == 0) {
3411                         $guards = null;
3412                         $this->seek($s);
3413                         return false;
3414                 }
3415
3416                 return true;
3417         }
3418
3419         // a bunch of guards that are and'd together
3420         // TODO rename to guardGroup
3421         protected function guardGroup(&$guardGroup) {
3422                 $s = $this->seek();
3423                 $guardGroup = array();
3424                 while ($this->guard($guard)) {
3425                         $guardGroup[] = $guard;
3426                         if (!$this->literal("and")) break;
3427                 }
3428
3429                 if (count($guardGroup) == 0) {
3430                         $guardGroup = null;
3431                         $this->seek($s);
3432                         return false;
3433                 }
3434
3435                 return true;
3436         }
3437
3438         protected function guard(&$guard) {
3439                 $s = $this->seek();
3440                 $negate = $this->literal("not");
3441
3442                 if ($this->literal("(") && $this->expression($exp) && $this->literal(")")) {
3443                         $guard = $exp;
3444                         if ($negate) $guard = array("negate", $guard);
3445                         return true;
3446                 }
3447
3448                 $this->seek($s);
3449                 return false;
3450         }
3451
3452         /* raw parsing functions */
3453
3454         protected function literal($what, $eatWhitespace = null) {
3455                 if ($eatWhitespace === null) $eatWhitespace = $this->eatWhiteDefault;
3456
3457                 // shortcut on single letter
3458                 if (!isset($what[1]) && isset($this->buffer[$this->count])) {
3459                         if ($this->buffer[$this->count] == $what) {
3460                                 if (!$eatWhitespace) {
3461                                         $this->count++;
3462                                         return true;
3463                                 }
3464                                 // goes below...
3465                         } else {
3466                                 return false;
3467                         }
3468                 }
3469
3470                 if (!isset(self::$literalCache[$what])) {
3471                         self::$literalCache[$what] = lessc::preg_quote($what);
3472                 }
3473
3474                 return $this->match(self::$literalCache[$what], $m, $eatWhitespace);
3475         }
3476
3477         protected function genericList(&$out, $parseItem, $delim="", $flatten=true) {
3478                 $s = $this->seek();
3479                 $items = array();
3480                 while ($this->$parseItem($value)) {
3481                         $items[] = $value;
3482                         if ($delim) {
3483                                 if (!$this->literal($delim)) break;
3484                         }
3485                 }
3486
3487                 if (count($items) == 0) {
3488                         $this->seek($s);
3489                         return false;
3490                 }
3491
3492                 if ($flatten && count($items) == 1) {
3493                         $out = $items[0];
3494                 } else {
3495                         $out = array("list", $delim, $items);
3496                 }
3497
3498                 return true;
3499         }
3500
3501
3502         // advance counter to next occurrence of $what
3503         // $until - don't include $what in advance
3504         // $allowNewline, if string, will be used as valid char set
3505         protected function to($what, &$out, $until = false, $allowNewline = false) {
3506                 if (is_string($allowNewline)) {
3507                         $validChars = $allowNewline;
3508                 } else {
3509                         $validChars = $allowNewline ? "." : "[^\n]";
3510                 }
3511                 if (!$this->match('('.$validChars.'*?)'.lessc::preg_quote($what), $m, !$until)) return false;
3512                 if ($until) $this->count -= strlen($what); // give back $what
3513                 $out = $m[1];
3514                 return true;
3515         }
3516
3517         // try to match something on head of buffer
3518         protected function match($regex, &$out, $eatWhitespace = null) {
3519                 if ($eatWhitespace === null) $eatWhitespace = $this->eatWhiteDefault;
3520
3521                 $r = '/'.$regex.($eatWhitespace && !$this->writeComments ? '\s*' : '').'/Ais';
3522                 if (preg_match($r, $this->buffer, $out, null, $this->count)) {
3523                         $this->count += strlen($out[0]);
3524                         if ($eatWhitespace && $this->writeComments) $this->whitespace();
3525                         return true;
3526                 }
3527                 return false;
3528         }
3529
3530         // match some whitespace
3531         protected function whitespace() {
3532                 if ($this->writeComments) {
3533                         $gotWhite = false;
3534                         while (preg_match(self::$whitePattern, $this->buffer, $m, null, $this->count)) {
3535                                 if (isset($m[1]) && empty($this->seenComments[$this->count])) {
3536                                         $this->append(array("comment", $m[1]));
3537                                         $this->seenComments[$this->count] = true;
3538                                 }
3539                                 $this->count += strlen($m[0]);
3540                                 $gotWhite = true;
3541                         }
3542                         return $gotWhite;
3543                 } else {
3544                         $this->match("", $m);
3545                         return strlen($m[0]) > 0;
3546                 }
3547         }
3548
3549         // match something without consuming it
3550         protected function peek($regex, &$out = null, $from=null) {
3551                 if (is_null($from)) $from = $this->count;
3552                 $r = '/'.$regex.'/Ais';
3553                 $result = preg_match($r, $this->buffer, $out, null, $from);
3554
3555                 return $result;
3556         }
3557
3558         // seek to a spot in the buffer or return where we are on no argument
3559         protected function seek($where = null) {
3560                 if ($where === null) return $this->count;
3561                 else $this->count = $where;
3562                 return true;
3563         }
3564
3565         /* misc functions */
3566
3567         public function throwError($msg = "parse error", $count = null) {
3568                 $count = is_null($count) ? $this->count : $count;
3569
3570                 $line = $this->line +
3571                         substr_count(substr($this->buffer, 0, $count), "\n");
3572
3573                 if (!empty($this->sourceName)) {
3574                         $loc = "$this->sourceName on line $line";
3575                 } else {
3576                         $loc = "line: $line";
3577                 }
3578
3579                 // TODO this depends on $this->count
3580                 if ($this->peek("(.*?)(\n|$)", $m, $count)) {
3581                         throw new exception("$msg: failed at `$m[1]` $loc");
3582                 } else {
3583                         throw new exception("$msg: $loc");
3584                 }
3585         }
3586
3587         protected function pushBlock($selectors=null, $type=null) {
3588                 $b = new stdclass;
3589                 $b->parent = $this->env;
3590
3591                 $b->type = $type;
3592                 $b->id = self::$nextBlockId++;
3593
3594                 $b->isVararg = false; // TODO: kill me from here
3595                 $b->tags = $selectors;
3596
3597                 $b->props = array();
3598                 $b->children = array();
3599
3600                 $this->env = $b;
3601                 return $b;
3602         }
3603
3604         // push a block that doesn't multiply tags
3605         protected function pushSpecialBlock($type) {
3606                 return $this->pushBlock(null, $type);
3607         }
3608
3609         // append a property to the current block
3610         protected function append($prop, $pos = null) {
3611                 if ($pos !== null) $prop[-1] = $pos;
3612                 $this->env->props[] = $prop;
3613         }
3614
3615         // pop something off the stack
3616         protected function pop() {
3617                 $old = $this->env;
3618                 $this->env = $this->env->parent;
3619                 return $old;
3620         }
3621
3622         // remove comments from $text
3623         // todo: make it work for all functions, not just url
3624         protected function removeComments($text) {
3625                 $look = array(
3626                         'url(', '//', '/*', '"', "'"
3627                 );
3628
3629                 $out = '';
3630                 $min = null;
3631                 while (true) {
3632                         // find the next item
3633                         foreach ($look as $token) {
3634                                 $pos = strpos($text, $token);
3635                                 if ($pos !== false) {
3636                                         if (!isset($min) || $pos < $min[1]) $min = array($token, $pos);
3637                                 }
3638                         }
3639
3640                         if (is_null($min)) break;
3641
3642                         $count = $min[1];
3643                         $skip = 0;
3644                         $newlines = 0;
3645                         switch ($min[0]) {
3646                         case 'url(':
3647                                 if (preg_match('/url\(.*?\)/', $text, $m, 0, $count))
3648                                         $count += strlen($m[0]) - strlen($min[0]);
3649                                 break;
3650                         case '"':
3651                         case "'":
3652                                 if (preg_match('/'.$min[0].'.*?(?<!\\\\)'.$min[0].'/', $text, $m, 0, $count))
3653                                         $count += strlen($m[0]) - 1;
3654                                 break;
3655                         case '//':
3656                                 $skip = strpos($text, "\n", $count);
3657                                 if ($skip === false) $skip = strlen($text) - $count;
3658                                 else $skip -= $count;
3659                                 break;
3660                         case '/*':
3661                                 if (preg_match('/\/\*.*?\*\//s', $text, $m, 0, $count)) {
3662                                         $skip = strlen($m[0]);
3663                                         $newlines = substr_count($m[0], "\n");
3664                                 }
3665                                 break;
3666                         }
3667
3668                         if ($skip == 0) $count += strlen($min[0]);
3669
3670                         $out .= substr($text, 0, $count).str_repeat("\n", $newlines);
3671                         $text = substr($text, $count + $skip);
3672
3673                         $min = null;
3674                 }
3675
3676                 return $out.$text;
3677         }
3678
3679 }
3680
3681 class lessc_formatter_classic {
3682         public $indentChar = "  ";
3683
3684         public $break = "\n";
3685         public $open = " {";
3686         public $close = "}";
3687         public $selectorSeparator = ", ";
3688         public $assignSeparator = ":";
3689
3690         public $openSingle = " { ";
3691         public $closeSingle = " }";
3692
3693         public $disableSingle = false;
3694         public $breakSelectors = false;
3695
3696         public $compressColors = false;
3697
3698         public function __construct() {
3699                 $this->indentLevel = 0;
3700         }
3701
3702         public function indentStr($n = 0) {
3703                 return str_repeat($this->indentChar, max($this->indentLevel + $n, 0));
3704         }
3705
3706         public function property($name, $value) {
3707                 return $name . $this->assignSeparator . $value . ";";
3708         }
3709
3710         protected function isEmpty($block) {
3711                 if (empty($block->lines)) {
3712                         foreach ($block->children as $child) {
3713                                 if (!$this->isEmpty($child)) return false;
3714                         }
3715
3716                         return true;
3717                 }
3718                 return false;
3719         }
3720
3721         public function block($block) {
3722                 if ($this->isEmpty($block)) return;
3723
3724                 $inner = $pre = $this->indentStr();
3725
3726                 $isSingle = !$this->disableSingle &&
3727                         is_null($block->type) && count($block->lines) == 1;
3728
3729                 if (!empty($block->selectors)) {
3730                         $this->indentLevel++;
3731
3732                         if ($this->breakSelectors) {
3733                                 $selectorSeparator = $this->selectorSeparator . $this->break . $pre;
3734                         } else {
3735                                 $selectorSeparator = $this->selectorSeparator;
3736                         }
3737
3738                         echo $pre .
3739                                 implode($selectorSeparator, $block->selectors);
3740                         if ($isSingle) {
3741                                 echo $this->openSingle;
3742                                 $inner = "";
3743                         } else {
3744                                 echo $this->open . $this->break;
3745                                 $inner = $this->indentStr();
3746                         }
3747
3748                 }
3749
3750                 if (!empty($block->lines)) {
3751                         $glue = $this->break.$inner;
3752                         echo $inner . implode($glue, $block->lines);
3753                         if (!$isSingle && !empty($block->children)) {
3754                                 echo $this->break;
3755                         }
3756                 }
3757
3758                 foreach ($block->children as $child) {
3759                         $this->block($child);
3760                 }
3761
3762                 if (!empty($block->selectors)) {
3763                         if (!$isSingle && empty($block->children)) echo $this->break;
3764
3765                         if ($isSingle) {
3766                                 echo $this->closeSingle . $this->break;
3767                         } else {
3768                                 echo $pre . $this->close . $this->break;
3769                         }
3770
3771                         $this->indentLevel--;
3772                 }
3773         }
3774 }
3775
3776 class lessc_formatter_compressed extends lessc_formatter_classic {
3777         public $disableSingle = true;
3778         public $open = "{";
3779         public $selectorSeparator = ",";
3780         public $assignSeparator = ":";
3781         public $break = "";
3782         public $compressColors = true;
3783
3784         public function indentStr($n = 0) {
3785                 return "";
3786         }
3787 }
3788
3789 class lessc_formatter_lessjs extends lessc_formatter_classic {
3790         public $disableSingle = true;
3791         public $breakSelectors = true;
3792         public $assignSeparator = ": ";
3793         public $selectorSeparator = ",";
3794 }
3795
3796