includes/Message.php

   1 <?php
   2 /**
   3  * This class provides methods for fetching interface messages and
   4  * processing them into variety of formats that are needed in MediaWiki.
   5  *
   6  * It is intented to replace the old wfMsg* functions that over time grew
   7  * unusable.
   8  *
   9  * Examples:
  10  * Fetching a message text for interface message
  11  *    $button = Xml::button( wfMessage( 'submit' )->text() );
  12  * </pre>
  13  * Messages can have parameters:
  14  *    wfMessage( 'welcome-to' )->params( $wgSitename )->text();
  15  *        {{GRAMMAR}} and friends work correctly
  16  *    wfMessage( 'are-friends', $user, $friend );
  17  *    wfMessage( 'bad-message' )->rawParams( '<script>...</script>' )->escaped();
  18  * </pre>
  19  * Sometimes the message text ends up in the database, so content language is needed.
  20  *    wfMessage( 'file-log', $user, $filename )->inContentLanguage()->text()
  21  * </pre>
  22  * Checking if message exists:
  23  *    wfMessage( 'mysterious-message' )->exists()
  24  * </pre>
  25  * If you want to use a different language:
  26  *    wfMessage( 'email-header' )->inLanguage( $user->getOption( 'language' ) )->plain()
  27  *        Note that you cannot parse the text except in the content or interface
  28  *        languages
  29  * </pre>
  30  *
  31  *
  32  * Comparison with old wfMsg* functions:
  33  *
  34  * Use full parsing.
  35  *     wfMsgExt( 'key', array( 'parseinline' ), 'apple' );
  36  *     === wfMessage( 'key', 'apple' )->parse();
  37  * </pre>
  38  * Parseinline is used because it is more useful when pre-building html.
  39  * In normal use it is better to use OutputPage::(add|wrap)WikiMsg.
  40  *
  41  * Places where html cannot be used. {{-transformation is done.
  42  *     wfMsgExt( 'key', array( 'parsemag' ), 'apple', 'pear' );
  43  *     === wfMessage( 'key', 'apple', 'pear' )->text();
  44  * </pre>
  45  *
  46  * Shortcut for escaping the message too, similar to wfMsgHTML, but
  47  * parameters are not replaced after escaping by default.
  48  * $escaped = wfMessage( 'key' )->rawParams( 'apple' )->escaped();
  49  * </pre>
  50  *
  51  * TODO:
  52  * - test, can we have tests?
  53  * - sort out the details marked with fixme
  54  *
  55  * @since 1.17
  56  * @author Niklas Laxström
  57  */
  58 class Message {
  59         /**
  60          * In which language to get this message. True, which is the default,
  61          * means the current interface language, false content language.
  62          */
  63         protected $interface = true;
  64
  65         /**
  66          * In which language to get this message. Overrides the $interface
  67          * variable.
  68          */
  69         protected $language = null;
  70
  71         /**
  72          * The message key.
  73          */
  74         protected $key;
  75
  76         /**
  77          * List of parameters which will be substituted into the message.
  78          */
  79         protected $parameters = array();
  80
  81         /**
  82          * Format for the message.
  83          * Supported formats are:
  84          * * text (transform)
  85          * * escaped (transform+htmlspecialchars)
  86          * * block-parse
  87          * * parse (default)
  88          * * plain
  89          */
  90         protected $format = 'parse';
  91
  92         /**
  93          * Whether database can be used.
  94          */
  95         protected $useDatabase = true;
  96
  97         /**
  98          * Constructor.
  99          * @param $key: message key, or array of message keys to try and use the first non-empty message for
 100          * @param $params Array message parameters
 101          * @return Message: $this
 102          */
 103         public function __construct( $key, $params = array() ) {
 104                 global $wgLang;
 105                 $this->key = $key;
 106                 $this->parameters = array_values( $params );
 107                 $this->language = $wgLang;
 108         }
 109
 110         /**
 111          * Factory function that is just wrapper for the real constructor. It is
 112          * intented to be used instead of the real constructor, because it allows
 113          * chaining method calls, while new objects don't.
 114          * @param $key String: message key
 115          * @param Varargs: parameters as Strings
 116          * @return Message: $this
 117          */
 118         public static function newFromKey( $key /*...*/ ) {
 119                 $params = func_get_args();
 120                 array_shift( $params );
 121                 return new self( $key, $params );
 122         }
 123
 124         /**
 125          * Factory function accepting multiple message keys and returning a message instance
 126          * for the first message which is non-empty. If all messages are empty then an
 127          * instance of the first message key is returned.
 128          * @param Varargs: message keys
 129          * @return Message: $this
 130          */
 131         public static function newFallbackSequence( /*...*/ ) {
 132                 $keys = func_get_args();
 133                 if ( func_num_args() == 1 ) {
 134                         if ( is_array($keys[0]) ) {
 135                                 // Allow an array to be passed as the first argument instead
 136                                 $keys = array_values($keys[0]);
 137                         } else {
 138                                 // Optimize a single string to not need special fallback handling
 139                                 $keys = $keys[0];
 140                         }
 141                 }
 142                 return new self( $keys );
 143         }
 144
 145         /**
 146          * Adds parameters to the parameter list of this message.
 147          * @param Varargs: parameters as Strings
 148          * @return Message: $this
 149          */
 150         public function params( /*...*/ ) {
 151                 $args_values = array_values( func_get_args() );
 152                 $this->parameters = array_merge( $this->parameters, $args_values );
 153                 return $this;
 154         }
 155
 156         /**
 157          * Add parameters that are substituted after parsing or escaping.
 158          * In other words the parsing process cannot access the contents
 159          * of this type of parameter, and you need to make sure it is
 160          * sanitized beforehand.  The parser will see "$n", instead.
 161          * @param Varargs: raw parameters as Strings
 162          * @return Message: $this
 163          */
 164         public function rawParams( /*...*/ ) {
 165                 $params = func_get_args();
 166                 foreach( $params as $param ) {
 167                         $this->parameters[] = self::rawParam( $param );
 168                 }
 169                 return $this;
 170         }
 171
 172         /**
 173          * Add parameters that are numeric and will be passed through
 174          * Language::formatNum before substitution
 175          * @param Varargs: numeric parameters
 176          * @return Message: $this
 177          */
 178         public function numParams( /*...*/ ) {
 179                 $params = func_get_args();
 180                 foreach( $params as $param ) {
 181                         $this->parameters[] = self::numParam( $param );
 182                 }
 183                 return $this;
 184         }
 185
 186         /**
 187          * Request the message in any language that is supported.
 188          * As a side effect interface message status is unconditionally
 189          * turned off.
 190          * @param $lang Mixed: language code or Language object.
 191          * @return Message: $this
 192          */
 193         public function inLanguage( $lang ) {
 194                 if( $lang instanceof Language ){
 195                         $this->language = $lang;
 196                 } elseif ( is_string( $lang ) ) {
 197                         if( $this->language->getCode() != $lang ) {
 198                                 $this->language = Language::factory( $lang );
 199                         }
 200                 } else {
 201                         $type = gettype( $lang );
 202                         throw new MWException( __METHOD__ . " must be "
 203                                 . "passed a String or Language object; $type given"
 204                         );
 205                 }
 206                 $this->interface = false;
 207                 return $this;
 208         }
 209
 210         /**
 211          * Request the message in the wiki's content language.
 212          * @return Message: $this
 213          */
 214         public function inContentLanguage() {
 215                 global $wgContLang;
 216                 $this->interface = false;
 217                 $this->language = $wgContLang;
 218                 return $this;
 219         }
 220
 221         /**
 222          * Enable or disable database use.
 223          * @param $value Boolean
 224          * @return Message: $this
 225          */
 226         public function useDatabase( $value ) {
 227                 $this->useDatabase = (bool) $value;
 228                 return $this;
 229         }
 230
 231         /**
 232          * Returns the message parsed from wikitext to HTML.
 233          * TODO: in PHP >= 5.2.0, we can make this a magic method,
 234          * and then we can do, eg:
 235          *     $foo = Message::get($key);
 236          *     $string = "<abbr>$foo</abbr>";
 237          * But we shouldn't implement that while MediaWiki still supports
 238          * PHP < 5.2; or people will start using it...
 239          * @return String: HTML
 240          */
 241         public function toString() {
 242                 $string = $this->getMessageText();
 243
 244                 # Replace parameters before text parsing
 245                 $string = $this->replaceParameters( $string, 'before' );
 246
 247                 # Maybe transform using the full parser
 248                 if( $this->format === 'parse' ) {
 249                         $string = $this->parseText( $string );
 250                         $m = array();
 251                         if( preg_match( '/^<p>(.*)\n?<\/p>\n?$/sU', $string, $m ) ) {
 252                                 $string = $m[1];
 253                         }
 254                 } elseif( $this->format === 'block-parse' ){
 255                         $string = $this->parseText( $string );
 256                 } elseif( $this->format === 'text' ){
 257                         $string = $this->transformText( $string );
 258                 } elseif( $this->format === 'escaped' ){
 259                         # FIXME: Sanitizer method here?
 260                         $string = $this->transformText( $string );
 261                         $string = htmlspecialchars( $string );
 262                 }
 263
 264                 # Raw parameter replacement
 265                 $string = $this->replaceParameters( $string, 'after' );
 266
 267                 return $string;
 268         }
 269
 270         /**
 271          * Fully parse the text from wikitext to HTML
 272          * @return String parsed HTML
 273          */
 274         public function parse() {
 275                 $this->format = 'parse';
 276                 return $this->toString();
 277         }
 278
 279         /**
 280          * Returns the message text. {{-transformation is done.
 281          * @return String: Unescaped message text.
 282          */
 283         public function text() {
 284                 $this->format = 'text';
 285                 return $this->toString();
 286         }
 287
 288         /**
 289          * Returns the message text as-is, only parameters are subsituted.
 290          * @return String: Unescaped untransformed message text.
 291          */
 292         public function plain() {
 293                 $this->format = 'plain';
 294                 return $this->toString();
 295         }
 296
 297         /**
 298          * Returns the parsed message text which is always surrounded by a block element.
 299          * @return String: HTML
 300          */
 301         public function parseAsBlock() {
 302                 $this->format = 'block-parse';
 303                 return $this->toString();
 304         }
 305
 306         /**
 307          * Returns the message text. {{-transformation is done and the result
 308          * is escaped excluding any raw parameters.
 309          * @return String: Escaped message text.
 310          */
 311         public function escaped() {
 312                 $this->format = 'escaped';
 313                 return $this->toString();
 314         }
 315
 316         /**
 317          * Check whether a message key has been defined currently.
 318          * @return Bool: true if it is and false if not.
 319          */
 320         public function exists() {
 321                 return $this->fetchMessage() !== false;
 322         }
 323
 324         /**
 325          * Check whether a message does not exist, or is an empty string
 326          * @return Bool: true if is is and false if not
 327          */
 328         public function isBlank() {
 329                 $message = $this->fetchMessage();
 330                 return $message === false || $message === '';
 331         }
 332
 333         /**
 334          * Check whether a message does not exist, is an empty string, or is "-"
 335          * @return Bool: true if is is and false if not
 336          */
 337         public function isDisabled() {
 338                 $message = $this->fetchMessage();
 339                 return $message === false || $message === '' || $message === '-';
 340         }
 341
 342         public static function rawParam( $value ) {
 343                 return array( 'raw' => $value );
 344         }
 345
 346         public static function numParam( $value ) {
 347                 return array( 'num' => $value );
 348         }
 349
 350         /**
 351          * Substitutes any paramaters into the message text.
 352          * @param $message String, the message text
 353          * @param $type String: either before or after
 354          * @return String
 355          */
 356         protected function replaceParameters( $message, $type = 'before' ) {
 357                 $replacementKeys = array();
 358                 foreach( $this->parameters as $n => $param ) {
 359                         if ( $type === 'before' && !is_array( $param ) ) {
 360                                 $replacementKeys['$' . ($n + 1)] = $param;
 361                         } elseif ( $type === 'after' && isset( $param['raw'] ) ) {
 362                                 $replacementKeys['$' . ($n + 1)] = $param['raw'];
 363                         } elseif ( isset( $param['num'] ) ) {
 364                                 $replacementKeys['$' . ($n + 1)] =
 365                                         $this->language->formatNum( $param['num'] );
 366                         }
 367                 }
 368                 $message = strtr( $message, $replacementKeys );
 369                 return $message;
 370         }
 371
 372         /**
 373          * Wrapper for what ever method we use to parse wikitext.
 374          * @param $string String: Wikitext message contents
 375          * @return Wikitext parsed into HTML
 376          */
 377         protected function parseText( $string ) {
 378                 global $wgOut;
 379                 return $wgOut->parse( $string, /*linestart*/true, $this->interface, $this->language );
 380         }
 381
 382         /**
 383          * Wrapper for what ever method we use to {{-transform wikitext.
 384          * @param $string String: Wikitext message contents
 385          * @return Wikitext with {{-constructs replaced with their values.
 386          */
 387         protected function transformText( $string ) {
 388                 return MessageCache::singleton()->transform( $string, $this->interface, $this->language );
 389         }
 390
 391         /**
 392          * Returns the textual value for the message.
 393          * @return Message contents or placeholder
 394          */
 395         protected function getMessageText() {
 396                 $message = $this->fetchMessage();
 397                 if ( $message === false ) {
 398                         return '&lt;' . htmlspecialchars( is_array($this->key) ? $this->key[0] : $this->key ) . '&gt;';
 399                 } else {
 400                         return $message;
 401                 }
 402         }
 403
 404         /**
 405          * Wrapper for what ever method we use to get message contents
 406          */
 407         protected function fetchMessage() {
 408                 if ( !isset( $this->message ) ) {
 409                         $cache = MessageCache::singleton();
 410                         if ( is_array($this->key) ) {
 411                                 foreach ( $this->key as $key ) {
 412                                         $message = $cache->get( $key, $this->useDatabase, $this->language );
 413                                         if ( $message !== false && $message !== '' ) {
 414                                                 break;
 415                                         }
 416                                 }
 417                                 $this->message = $message;
 418                         } else {
 419                                 $this->message = $cache->get( $this->key, $this->useDatabase, $this->language );
 420                         }
 421                 }
 422                 return $this->message;
 423         }
 424
 425 }