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  *
  54  * @since 1.17
  55  * @author Niklas Laxström
  56  */
  57 class Message {
  58         /**
  59          * In which language to get this message. True, which is the default,
  60          * means the current interface language, false content language.
  61          */
  62         protected $interface = true;
  63
  64         /**
  65          * In which language to get this message. Overrides the $interface
  66          * variable.
  67          *
  68          * @var Language
  69          */
  70         protected $language = null;
  71
  72         /**
  73          * The message key.
  74          */
  75         protected $key;
  76
  77         /**
  78          * List of parameters which will be substituted into the message.
  79          */
  80         protected $parameters = array();
  81
  82         /**
  83          * Format for the message.
  84          * Supported formats are:
  85          * * text (transform)
  86          * * escaped (transform+htmlspecialchars)
  87          * * block-parse
  88          * * parse (default)
  89          * * plain
  90          */
  91         protected $format = 'parse';
  92
  93         /**
  94          * Whether database can be used.
  95          */
  96         protected $useDatabase = true;
  97
  98         /**
  99          * Title object to use as context
 100          */
 101         protected $title = null;
 102
 103         /**
 104          * Constructor.
 105          * @param $key: message key, or array of message keys to try and use the first non-empty message for
 106          * @param $params Array message parameters
 107          * @return Message: $this
 108          */
 109         public function __construct( $key, $params = array() ) {
 110                 global $wgLang;
 111                 $this->key = $key;
 112                 $this->parameters = array_values( $params );
 113                 $this->language = $wgLang;
 114         }
 115
 116         /**
 117          * Factory function that is just wrapper for the real constructor. It is
 118          * intented to be used instead of the real constructor, because it allows
 119          * chaining method calls, while new objects don't.
 120          * @param $key String: message key
 121          * @param Varargs: parameters as Strings
 122          * @return Message: $this
 123          */
 124         public static function newFromKey( $key /*...*/ ) {
 125                 $params = func_get_args();
 126                 array_shift( $params );
 127                 return new self( $key, $params );
 128         }
 129
 130         /**
 131          * Factory function accepting multiple message keys and returning a message instance
 132          * for the first message which is non-empty. If all messages are empty then an
 133          * instance of the first message key is returned.
 134          * @param Varargs: message keys
 135          * @return Message: $this
 136          */
 137         public static function newFallbackSequence( /*...*/ ) {
 138                 $keys = func_get_args();
 139                 if ( func_num_args() == 1 ) {
 140                         if ( is_array($keys[0]) ) {
 141                                 // Allow an array to be passed as the first argument instead
 142                                 $keys = array_values($keys[0]);
 143                         } else {
 144                                 // Optimize a single string to not need special fallback handling
 145                                 $keys = $keys[0];
 146                         }
 147                 }
 148                 return new self( $keys );
 149         }
 150
 151         /**
 152          * Adds parameters to the parameter list of this message.
 153          * @param Varargs: parameters as Strings
 154          * @return Message: $this
 155          */
 156         public function params( /*...*/ ) {
 157                 $args = func_get_args();
 158                 if ( isset( $args[0] ) && is_array( $args[0] ) ) {
 159                         $args = $args[0];
 160                 }
 161                 $args_values = array_values( $args );
 162                 $this->parameters = array_merge( $this->parameters, $args_values );
 163                 return $this;
 164         }
 165
 166         /**
 167          * Add parameters that are substituted after parsing or escaping.
 168          * In other words the parsing process cannot access the contents
 169          * of this type of parameter, and you need to make sure it is
 170          * sanitized beforehand.  The parser will see "$n", instead.
 171          * @param Varargs: raw parameters as Strings
 172          * @return Message: $this
 173          */
 174         public function rawParams( /*...*/ ) {
 175                 $params = func_get_args();
 176                 if ( isset( $params[0] ) && is_array( $params[0] ) ) {
 177                         $params = $params[0];
 178                 }
 179                 foreach( $params as $param ) {
 180                         $this->parameters[] = self::rawParam( $param );
 181                 }
 182                 return $this;
 183         }
 184
 185         /**
 186          * Add parameters that are numeric and will be passed through
 187          * Language::formatNum before substitution
 188          * @param Varargs: numeric parameters
 189          * @return Message: $this
 190          */
 191         public function numParams( /*...*/ ) {
 192                 $params = func_get_args();
 193                 if ( isset( $params[0] ) && is_array( $params[0] ) ) {
 194                         $params = $params[0];
 195                 }
 196                 foreach( $params as $param ) {
 197                         $this->parameters[] = self::numParam( $param );
 198                 }
 199                 return $this;
 200         }
 201
 202         /**
 203          * Request the message in any language that is supported.
 204          * As a side effect interface message status is unconditionally
 205          * turned off.
 206          * @param $lang Mixed: language code or Language object.
 207          * @return Message: $this
 208          */
 209         public function inLanguage( $lang ) {
 210                 if ( $lang instanceof Language || $lang instanceof StubUserLang ) {
 211                         $this->language = $lang;
 212                 } elseif ( is_string( $lang ) ) {
 213                         if( $this->language->getCode() != $lang ) {
 214                                 $this->language = Language::factory( $lang );
 215                         }
 216                 } else {
 217                         $type = gettype( $lang );
 218                         throw new MWException( __METHOD__ . " must be "
 219                                 . "passed a String or Language object; $type given"
 220                         );
 221                 }
 222                 $this->interface = false;
 223                 return $this;
 224         }
 225
 226         /**
 227          * Request the message in the wiki's content language.
 228          * @return Message: $this
 229          */
 230         public function inContentLanguage() {
 231                 global $wgContLang;
 232                 $this->interface = false;
 233                 $this->language = $wgContLang;
 234                 return $this;
 235         }
 236
 237         /**
 238          * Enable or disable database use.
 239          * @param $value Boolean
 240          * @return Message: $this
 241          */
 242         public function useDatabase( $value ) {
 243                 $this->useDatabase = (bool) $value;
 244                 return $this;
 245         }
 246
 247         /**
 248          * Set the Title object to use as context when transforming the message
 249          *
 250          * @param $title Title object
 251          * @return Message: $this
 252          */
 253         public function title( $title ) {
 254                 $this->title = $title;
 255                 return $this;
 256         }
 257
 258         /**
 259          * Returns the message parsed from wikitext to HTML.
 260          * @return String: HTML
 261          */
 262         public function toString() {
 263                 $string = $this->getMessageText();
 264
 265                 # Replace parameters before text parsing
 266                 $string = $this->replaceParameters( $string, 'before' );
 267
 268                 # Maybe transform using the full parser
 269                 if( $this->format === 'parse' ) {
 270                         $string = $this->parseText( $string );
 271                         $m = array();
 272                         if( preg_match( '/^<p>(.*)\n?<\/p>\n?$/sU', $string, $m ) ) {
 273                                 $string = $m[1];
 274                         }
 275                 } elseif( $this->format === 'block-parse' ){
 276                         $string = $this->parseText( $string );
 277                 } elseif( $this->format === 'text' ){
 278                         $string = $this->transformText( $string );
 279                 } elseif( $this->format === 'escaped' ){
 280                         $string = $this->transformText( $string );
 281                         $string = htmlspecialchars( $string, ENT_QUOTES, 'UTF-8', false );
 282                 }
 283
 284                 # Raw parameter replacement
 285                 $string = $this->replaceParameters( $string, 'after' );
 286
 287                 return $string;
 288         }
 289
 290         /**
 291          * Magic method implementation of the above (for PHP >= 5.2.0), so we can do, eg:
 292          *     $foo = Message::get($key);
 293          *     $string = "<abbr>$foo</abbr>";
 294          * @return String
 295          */
 296         public function __toString() {
 297                 return $this->toString();
 298         }
 299
 300         /**
 301          * Fully parse the text from wikitext to HTML
 302          * @return String parsed HTML
 303          */
 304         public function parse() {
 305                 $this->format = 'parse';
 306                 return $this->toString();
 307         }
 308
 309         /**
 310          * Returns the message text. {{-transformation is done.
 311          * @return String: Unescaped message text.
 312          */
 313         public function text() {
 314                 $this->format = 'text';
 315                 return $this->toString();
 316         }
 317
 318         /**
 319          * Returns the message text as-is, only parameters are subsituted.
 320          * @return String: Unescaped untransformed message text.
 321          */
 322         public function plain() {
 323                 $this->format = 'plain';
 324                 return $this->toString();
 325         }
 326
 327         /**
 328          * Returns the parsed message text which is always surrounded by a block element.
 329          * @return String: HTML
 330          */
 331         public function parseAsBlock() {
 332                 $this->format = 'block-parse';
 333                 return $this->toString();
 334         }
 335
 336         /**
 337          * Returns the message text. {{-transformation is done and the result
 338          * is escaped excluding any raw parameters.
 339          * @return String: Escaped message text.
 340          */
 341         public function escaped() {
 342                 $this->format = 'escaped';
 343                 return $this->toString();
 344         }
 345
 346         /**
 347          * Check whether a message key has been defined currently.
 348          * @return Bool: true if it is and false if not.
 349          */
 350         public function exists() {
 351                 return $this->fetchMessage() !== false;
 352         }
 353
 354         /**
 355          * Check whether a message does not exist, or is an empty string
 356          * @return Bool: true if is is and false if not
 357          * @todo FIXME: Merge with isDisabled()?
 358          */
 359         public function isBlank() {
 360                 $message = $this->fetchMessage();
 361                 return $message === false || $message === '';
 362         }
 363
 364         /**
 365          * Check whether a message does not exist, is an empty string, or is "-"
 366          * @return Bool: true if is is and false if not
 367          */
 368         public function isDisabled() {
 369                 $message = $this->fetchMessage();
 370                 return $message === false || $message === '' || $message === '-';
 371         }
 372
 373         /**
 374          * @param $value
 375          * @return array
 376          */
 377         public static function rawParam( $value ) {
 378                 return array( 'raw' => $value );
 379         }
 380
 381         /**
 382          * @param $value
 383          * @return array
 384          */
 385         public static function numParam( $value ) {
 386                 return array( 'num' => $value );
 387         }
 388
 389         /**
 390          * Substitutes any paramaters into the message text.
 391          * @param $message String: the message text
 392          * @param $type String: either before or after
 393          * @return String
 394          */
 395         protected function replaceParameters( $message, $type = 'before' ) {
 396                 $replacementKeys = array();
 397                 foreach( $this->parameters as $n => $param ) {
 398                         list( $paramType, $value ) = $this->extractParam( $param );
 399                         if ( $type === $paramType ) {
 400                                 $replacementKeys['$' . ($n + 1)] = $value;
 401                         }
 402                 }
 403                 $message = strtr( $message, $replacementKeys );
 404                 return $message;
 405         }
 406
 407         /**
 408          * Extracts the parameter type and preprocessed the value if needed.
 409          * @param $param String|Array: Parameter as defined in this class.
 410          * @return Tuple(type, value)
 411          * @throws MWException
 412          */
 413         protected function extractParam( $param ) {
 414                 if ( is_array( $param ) && isset( $param['raw'] ) ) {
 415                         return array( 'after', $param['raw'] );
 416                 } elseif ( is_array( $param ) && isset( $param['num'] ) ) {
 417                         // Replace number params always in before step for now.
 418                         // No support for combined raw and num params
 419                         return array( 'before', $this->language->formatNum( $param['num'] ) );
 420                 } elseif ( !is_array( $param ) ) {
 421                         return array( 'before', $param );
 422                 } else {
 423                         throw new MWException( "Invalid message parameter" );
 424                 }
 425         }
 426
 427         /**
 428          * Wrapper for what ever method we use to parse wikitext.
 429          * @param $string String: Wikitext message contents
 430          * @return string Wikitext parsed into HTML
 431          */
 432         protected function parseText( $string ) {
 433                 return MessageCache::singleton()->parse( $string, $this->title, /*linestart*/true, $this->interface, $this->language )->getText();
 434         }
 435
 436         /**
 437          * Wrapper for what ever method we use to {{-transform wikitext.
 438          * @param $string String: Wikitext message contents
 439          * @return string Wikitext with {{-constructs replaced with their values.
 440          */
 441         protected function transformText( $string ) {
 442                 return MessageCache::singleton()->transform( $string, $this->interface, $this->language, $this->title );
 443         }
 444
 445         /**
 446          * Returns the textual value for the message.
 447          * @return Message contents or placeholder
 448          */
 449         protected function getMessageText() {
 450                 $message = $this->fetchMessage();
 451                 if ( $message === false ) {
 452                         return '&lt;' . htmlspecialchars( is_array($this->key) ? $this->key[0] : $this->key ) . '&gt;';
 453                 } else {
 454                         return $message;
 455                 }
 456         }
 457
 458         /**
 459          * Wrapper for what ever method we use to get message contents
 460          *
 461          * @return string
 462          */
 463         protected function fetchMessage() {
 464                 if ( !isset( $this->message ) ) {
 465                         $cache = MessageCache::singleton();
 466                         if ( is_array($this->key) ) {
 467                                 foreach ( $this->key as $key ) {
 468                                         $message = $cache->get( $key, $this->useDatabase, $this->language );
 469                                         if ( $message !== false && $message !== '' ) {
 470                                                 break;
 471                                         }
 472                                 }
 473                                 $this->message = $message;
 474                         } else {
 475                                 $this->message = $cache->get( $this->key, $this->useDatabase, $this->language );
 476                         }
 477                 }
 478                 return $this->message;
 479         }
 480
 481 }