includes/linker/LinkRenderer.php

   1 <?php
   2 /**
   3  * This program is free software; you can redistribute it and/or modify
   4  * it under the terms of the GNU General Public License as published by
   5  * the Free Software Foundation; either version 2 of the License, or
   6  * (at your option) any later version.
   7  *
   8  * This program is distributed in the hope that it will be useful,
   9  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  10  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
  11  * GNU General Public License for more details.
  12  *
  13  * You should have received a copy of the GNU General Public License along
  14  * with this program; if not, write to the Free Software Foundation, Inc.,
  15  * 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301, USA.
  16  * http://www.gnu.org/copyleft/gpl.html
  17  *
  18  * @file
  19  * @license GPL-2.0+
  20  * @author Kunal Mehta <legoktm@member.fsf.org>
  21  */
  22 namespace MediaWiki\Linker;
  23
  24 use DummyLinker;
  25 use Hooks;
  26 use Html;
  27 use HtmlArmor;
  28 use Linker;
  29 use MediaWiki\MediaWikiServices;
  30 use Sanitizer;
  31 use Title;
  32 use TitleFormatter;
  33
  34 /**
  35  * Class that generates HTML <a> links for pages.
  36  *
  37  * @since 1.28
  38  */
  39 class LinkRenderer {
  40
  41         /**
  42          * Whether to force the pretty article path
  43          *
  44          * @var bool
  45          */
  46         private $forceArticlePath = false;
  47
  48         /**
  49          * A PROTO_* constant or false
  50          *
  51          * @var string|bool|int
  52          */
  53         private $expandUrls = false;
  54
  55         /**
  56          * @var int
  57          */
  58         private $stubThreshold = 0;
  59
  60         /**
  61          * @var TitleFormatter
  62          */
  63         private $titleFormatter;
  64
  65         /**
  66          * Whether to run the legacy Linker hooks
  67          *
  68          * @var bool
  69          */
  70         private $runLegacyBeginHook = true;
  71
  72         /**
  73          * @param TitleFormatter $titleFormatter
  74          */
  75         public function __construct( TitleFormatter $titleFormatter ) {
  76                 $this->titleFormatter = $titleFormatter;
  77         }
  78
  79         /**
  80          * @param bool $force
  81          */
  82         public function setForceArticlePath( $force ) {
  83                 $this->forceArticlePath = $force;
  84         }
  85
  86         /**
  87          * @return bool
  88          */
  89         public function getForceArticlePath() {
  90                 return $this->forceArticlePath;
  91         }
  92
  93         /**
  94          * @param string|bool|int $expand A PROTO_* constant or false
  95          */
  96         public function setExpandURLs( $expand ) {
  97                 $this->expandUrls = $expand;
  98         }
  99
 100         /**
 101          * @return string|bool|int a PROTO_* constant or false
 102          */
 103         public function getExpandURLs() {
 104                 return $this->expandUrls;
 105         }
 106
 107         /**
 108          * @param int $threshold
 109          */
 110         public function setStubThreshold( $threshold ) {
 111                 $this->stubThreshold = $threshold;
 112         }
 113
 114         /**
 115          * @return int
 116          */
 117         public function getStubThreshold() {
 118                 return $this->stubThreshold;
 119         }
 120
 121         /**
 122          * @param bool $run
 123          */
 124         public function setRunLegacyBeginHook( $run ) {
 125                 $this->runLegacyBeginHook = $run;
 126         }
 127
 128         /**
 129          * @param LinkTarget $target
 130          * @param string|HtmlArmor|null $text
 131          * @param array $extraAttribs
 132          * @param array $query
 133          * @return string
 134          */
 135         public function makeLink(
 136                 LinkTarget $target, $text = null, array $extraAttribs = [], array $query = []
 137         ) {
 138                 $title = Title::newFromLinkTarget( $target );
 139                 if ( $title->isKnown() ) {
 140                         return $this->makeKnownLink( $target, $text, $extraAttribs, $query );
 141                 } else {
 142                         return $this->makeBrokenLink( $target, $text, $extraAttribs, $query );
 143                 }
 144         }
 145
 146         /**
 147          * Get the options in the legacy format
 148          *
 149          * @param bool $isKnown Whether the link is known or broken
 150          * @return array
 151          */
 152         private function getLegacyOptions( $isKnown ) {
 153                 $options = [ 'stubThreshold' => $this->stubThreshold ];
 154                 if ( $this->forceArticlePath ) {
 155                         $options[] = 'forcearticlepath';
 156                 }
 157                 if ( $this->expandUrls === PROTO_HTTP ) {
 158                         $options[] = 'http';
 159                 } elseif ( $this->expandUrls === PROTO_HTTPS ) {
 160                         $options[] = 'https';
 161                 }
 162
 163                 $options[] = $isKnown ? 'known' : 'broken';
 164
 165                 return $options;
 166         }
 167
 168         private function runBeginHook( LinkTarget $target, &$text, &$extraAttribs, &$query, $isKnown ) {
 169                 $ret = null;
 170                 if ( !Hooks::run( 'HtmlPageLinkRendererBegin',
 171                         [ $this, $target, &$text, &$extraAttribs, &$query, &$ret ] )
 172                 ) {
 173                         return $ret;
 174                 }
 175
 176                 // Now run the legacy hook
 177                 return $this->runLegacyBeginHook( $target, $text, $extraAttribs, $query, $isKnown );
 178         }
 179
 180         private function runLegacyBeginHook( LinkTarget $target, &$text, &$extraAttribs, &$query,
 181                 $isKnown
 182         ) {
 183                 if ( !$this->runLegacyBeginHook || !Hooks::isRegistered( 'LinkBegin' ) ) {
 184                         // Disabled, or nothing registered
 185                         return null;
 186                 }
 187
 188                 $realOptions = $options = $this->getLegacyOptions( $isKnown );
 189                 $ret = null;
 190                 $dummy = new DummyLinker();
 191                 $title = Title::newFromLinkTarget( $target );
 192                 if ( $text !== null ) {
 193                         $realHtml = $html = HtmlArmor::getHtml( $text );
 194                 } else {
 195                         $realHtml = $html = null;
 196                 }
 197                 if ( !Hooks::run( 'LinkBegin',
 198                         [ $dummy, $title, &$html, &$extraAttribs, &$query, &$options, &$ret ] )
 199                 ) {
 200                         return $ret;
 201                 }
 202
 203                 if ( $html !== null && $html !== $realHtml ) {
 204                         // &$html was modified, so re-armor it as $text
 205                         $text = new HtmlArmor( $html );
 206                 }
 207
 208                 // Check if they changed any of the options, hopefully not!
 209                 if ( $options !== $realOptions ) {
 210                         $factory = MediaWikiServices::getInstance()->getLinkRendererFactory();
 211                         // They did, so create a separate instance and have that take over the rest
 212                         $newRenderer = $factory->createFromLegacyOptions( $options );
 213                         // Don't recurse the hook...
 214                         $newRenderer->setRunLegacyBeginHook( false );
 215                         if ( in_array( 'known', $options, true ) ) {
 216                                 return $newRenderer->makeKnownLink( $title, $text, $extraAttribs, $query );
 217                         } elseif ( in_array( 'broken', $options, true ) ) {
 218                                 return $newRenderer->makeBrokenLink( $title, $text, $extraAttribs, $query );
 219                         } else {
 220                                 return $newRenderer->makeLink( $title, $text, $extraAttribs, $query );
 221                         }
 222                 }
 223
 224                 return null;
 225         }
 226
 227         /**
 228          * If you have already looked up the proper CSS classes using Linker::getLinkColour()
 229          * or some other method, use this to avoid looking it up again.
 230          *
 231          * @param LinkTarget $target
 232          * @param string|HtmlArmor|null $text
 233          * @param string $classes CSS classes to add
 234          * @param array $extraAttribs
 235          * @param array $query
 236          * @return string
 237          */
 238         public function makePreloadedLink(
 239                 LinkTarget $target, $text = null, $classes, array $extraAttribs = [], array $query = []
 240         ) {
 241                 // Run begin hook
 242                 $ret = $this->runBeginHook( $target, $text, $extraAttribs, $query, true );
 243                 if ( $ret !== null ) {
 244                         return $ret;
 245                 }
 246                 $target = $this->normalizeTarget( $target );
 247                 $url = $this->getLinkURL( $target, $query );
 248                 $attribs = [ 'class' => $classes ];
 249                 $prefixedText = $this->titleFormatter->getPrefixedText( $target );
 250                 if ( $prefixedText !== '' ) {
 251                         $attribs['title'] = $prefixedText;
 252                 }
 253
 254                 $attribs = [
 255                         'href' => $url,
 256                 ] + $this->mergeAttribs( $attribs, $extraAttribs );
 257
 258                 if ( $text === null ) {
 259                         $text = $this->getLinkText( $target );
 260                 }
 261
 262                 return $this->buildAElement( $target, $text, $attribs, true );
 263         }
 264
 265         /**
 266          * @param LinkTarget $target
 267          * @param string|HtmlArmor|null $text
 268          * @param array $extraAttribs
 269          * @param array $query
 270          * @return string
 271          */
 272         public function makeKnownLink(
 273                 LinkTarget $target, $text = null, array $extraAttribs = [], array $query = []
 274         ) {
 275                 $classes = [];
 276                 if ( $target->isExternal() ) {
 277                         $classes[] = 'extiw';
 278                 }
 279                 $colour = Linker::getLinkColour( $target, $this->stubThreshold );
 280                 if ( $colour !== '' ) {
 281                         $classes[] = $colour;
 282                 }
 283
 284                 return $this->makePreloadedLink(
 285                         $target,
 286                         $text,
 287                         $classes ? implode( ' ', $classes ) : '',
 288                         $extraAttribs,
 289                         $query
 290                 );
 291         }
 292
 293         /**
 294          * @param LinkTarget $target
 295          * @param string|HtmlArmor|null $text
 296          * @param array $extraAttribs
 297          * @param array $query
 298          * @return string
 299          */
 300         public function makeBrokenLink(
 301                 LinkTarget $target, $text = null, array $extraAttribs = [], array $query = []
 302         ) {
 303                 // Run legacy hook
 304                 $ret = $this->runBeginHook( $target, $text, $extraAttribs, $query, false );
 305                 if ( $ret !== null ) {
 306                         return $ret;
 307                 }
 308
 309                 # We don't want to include fragments for broken links, because they
 310                 # generally make no sense.
 311                 if ( $target->hasFragment() ) {
 312                         $target = $target->createFragmentTarget( '' );
 313                 }
 314                 $target = $this->normalizeTarget( $target );
 315
 316                 if ( !isset( $query['action'] ) && $target->getNamespace() !== NS_SPECIAL ) {
 317                         $query['action'] = 'edit';
 318                         $query['redlink'] = '1';
 319                 }
 320
 321                 $url = $this->getLinkURL( $target, $query );
 322                 $attribs = [ 'class' => 'new' ];
 323                 $prefixedText = $this->titleFormatter->getPrefixedText( $target );
 324                 if ( $prefixedText !== '' ) {
 325                         // This ends up in parser cache!
 326                         $attribs['title'] = wfMessage( 'red-link-title', $prefixedText )
 327                                 ->inContentLanguage()
 328                                 ->text();
 329                 }
 330
 331                 $attribs = [
 332                         'href' => $url,
 333                 ] + $this->mergeAttribs( $attribs, $extraAttribs );
 334
 335                 if ( $text === null ) {
 336                         $text = $this->getLinkText( $target );
 337                 }
 338
 339                 return $this->buildAElement( $target, $text, $attribs, false );
 340         }
 341
 342         /**
 343          * Builds the final <a> element
 344          *
 345          * @param LinkTarget $target
 346          * @param string|HtmlArmor $text
 347          * @param array $attribs
 348          * @param bool $isKnown
 349          * @return null|string
 350          */
 351         private function buildAElement( LinkTarget $target, $text, array $attribs, $isKnown ) {
 352                 $ret = null;
 353                 if ( !Hooks::run( 'HtmlPageLinkRendererEnd',
 354                         [ $this, $target, $isKnown, &$text, &$attribs, &$ret ] )
 355                 ) {
 356                         return $ret;
 357                 }
 358
 359                 $html = HtmlArmor::getHtml( $text );
 360
 361                 // Run legacy hook
 362                 if ( Hooks::isRegistered( 'LinkEnd' ) ) {
 363                         $dummy = new DummyLinker();
 364                         $title = Title::newFromLinkTarget( $target );
 365                         $options = $this->getLegacyOptions( $isKnown );
 366                         if ( !Hooks::run( 'LinkEnd',
 367                                 [ $dummy, $title, $options, &$html, &$attribs, &$ret ] )
 368                         ) {
 369                                 return $ret;
 370                         }
 371                 }
 372
 373                 return Html::rawElement( 'a', $attribs, $html );
 374         }
 375
 376         /**
 377          * @param LinkTarget $target
 378          * @return string non-escaped text
 379          */
 380         private function getLinkText( LinkTarget $target ) {
 381                 $prefixedText = $this->titleFormatter->getPrefixedText( $target );
 382                 // If the target is just a fragment, with no title, we return the fragment
 383                 // text.  Otherwise, we return the title text itself.
 384                 if ( $prefixedText === '' && $target->hasFragment() ) {
 385                         return $target->getFragment();
 386                 }
 387
 388                 return $prefixedText;
 389         }
 390
 391         private function getLinkURL( LinkTarget $target, array $query = [] ) {
 392                 // TODO: Use a LinkTargetResolver service instead of Title
 393                 $title = Title::newFromLinkTarget( $target );
 394                 $proto = $this->expandUrls !== false
 395                         ? $this->expandUrls
 396                         : PROTO_RELATIVE;
 397                 if ( $this->forceArticlePath ) {
 398                         $realQuery = $query;
 399                         $query = [];
 400                 } else {
 401                         $realQuery = [];
 402                 }
 403                 $url = $title->getLinkURL( $query, false, $proto );
 404
 405                 if ( $this->forceArticlePath && $realQuery ) {
 406                         $url = wfAppendQuery( $url, $realQuery );
 407                 }
 408
 409                 return $url;
 410         }
 411
 412         /**
 413          * Normalizes the provided target
 414          *
 415          * @todo move the code from Linker actually here
 416          * @param LinkTarget $target
 417          * @return LinkTarget
 418          */
 419         private function normalizeTarget( LinkTarget $target ) {
 420                 return Linker::normaliseSpecialPage( $target );
 421         }
 422
 423         /**
 424          * Merges two sets of attributes
 425          *
 426          * @param array $defaults
 427          * @param array $attribs
 428          *
 429          * @return array
 430          */
 431         private function mergeAttribs( $defaults, $attribs ) {
 432                 if ( !$attribs ) {
 433                         return $defaults;
 434                 }
 435                 # Merge the custom attribs with the default ones, and iterate
 436                 # over that, deleting all "false" attributes.
 437                 $ret = [];
 438                 $merged = Sanitizer::mergeAttributes( $defaults, $attribs );
 439                 foreach ( $merged as $key => $val ) {
 440                         # A false value suppresses the attribute
 441                         if ( $val !== false ) {
 442                                 $ret[$key] = $val;
 443                         }
 444                 }
 445                 return $ret;
 446         }
 447
 448 }