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                 global $wgMessageCache;
 133                 $keys = func_get_args();
 134                 if ( func_num_args() == 1 ) {
 135                         if ( is_array($keys[0]) ) {
 136                                 // Allow an array to be passed as the first argument instead
 137                                 $keys = array_values($keys[0]);
 138                         } else {
 139                                 // Optimize a single string to not need special fallback handling
 140                                 $keys = $keys[0];
 141                         }
 142                 }
 143                 return new self( $keys );
 144         }
 145
 146         /**
 147          * Adds parameters to the parameter list of this message.
 148          * @param Varargs: parameters as Strings
 149          * @return Message: $this
 150          */
 151         public function params( /*...*/ ) {
 152                 $args_values = array_values( func_get_args() );
 153                 $this->parameters = array_merge( $this->parameters, $args_values );
 154                 return $this;
 155         }
 156
 157         /**
 158          * Add parameters that are substituted after parsing or escaping.
 159          * In other words the parsing process cannot access the contents
 160          * of this type of parameter, and you need to make sure it is
 161          * sanitized beforehand.  The parser will see "$n", instead.
 162          * @param Varargs: raw parameters as Strings
 163          * @return Message: $this
 164          */
 165         public function rawParams( /*...*/ ) {
 166                 $params = func_get_args();
 167                 foreach( $params as $param ) {
 168                         $this->parameters[] = self::rawParam( $param );
 169                 }
 170                 return $this;
 171         }
 172
 173         /**
 174          * Request the message in any language that is supported.
 175          * As a side effect interface message status is unconditionally
 176          * turned off.
 177          * @param $lang Mixed: language code or Language object.
 178          * @return Message: $this
 179          */
 180         public function inLanguage( $lang ) {
 181                 if( $lang instanceof Language ){
 182                         $this->language = $lang;
 183                 } elseif ( is_string( $lang ) ) {
 184                         if( $this->language->getCode() != $lang ) {
 185                                 $this->language = Language::factory( $lang );
 186                         }
 187                 } else {
 188                         $type = gettype( $lang );
 189                         throw new MWException( __METHOD__ . " must be "
 190                                 . "passed a String or Language object; $type given"
 191                         );
 192                 }
 193                 $this->interface = false;
 194                 return $this;
 195         }
 196
 197         /**
 198          * Request the message in the wiki's content language.
 199          * @return Message: $this
 200          */
 201         public function inContentLanguage() {
 202                 global $wgContLang;
 203                 $this->interface = false;
 204                 $this->language = $wgContLang;
 205                 return $this;
 206         }
 207
 208         /**
 209          * Enable or disable database use.
 210          * @param $value Boolean
 211          * @return Message: $this
 212          */
 213         public function useDatabase( $value ) {
 214                 $this->useDatabase = (bool) $value;
 215                 return $this;
 216         }
 217
 218         /**
 219          * Returns the message parsed from wikitext to HTML.
 220          * TODO: in PHP >= 5.2.0, we can make this a magic method,
 221          * and then we can do, eg:
 222          *     $foo = Message::get($key);
 223          *     $string = "<abbr>$foo</abbr>";
 224          * But we shouldn't implement that while MediaWiki still supports
 225          * PHP < 5.2; or people will start using it...
 226          * @return String: HTML
 227          */
 228         public function toString() {
 229                 $string = $this->getMessageText();
 230
 231                 # Replace parameters before text parsing
 232                 $string = $this->replaceParameters( $string, 'before' );
 233
 234                 # Maybe transform using the full parser
 235                 if( $this->format === 'parse' ) {
 236                         $string = $this->parseText( $string );
 237                         $m = array();
 238                         if( preg_match( '/^<p>(.*)\n?<\/p>\n?$/sU', $string, $m ) ) {
 239                                 $string = $m[1];
 240                         }
 241                 } elseif( $this->format === 'block-parse' ){
 242                         $string = $this->parseText( $string );
 243                 } elseif( $this->format === 'text' ){
 244                         $string = $this->transformText( $string );
 245                 } elseif( $this->format === 'escaped' ){
 246                         # FIXME: Sanitizer method here?
 247                         $string = $this->transformText( $string );
 248                         $string = htmlspecialchars( $string );
 249                 }
 250
 251                 # Raw parameter replacement
 252                 $string = $this->replaceParameters( $string, 'after' );
 253
 254                 return $string;
 255         }
 256
 257         /**
 258          * Fully parse the text from wikitext to HTML
 259          * @return String parsed HTML
 260          */
 261         public function parse() {
 262                 $this->format = 'parse';
 263                 return $this->toString();
 264         }
 265
 266         /**
 267          * Returns the message text. {{-transformation is done.
 268          * @return String: Unescaped message text.
 269          */
 270         public function text() {
 271                 $this->format = 'text';
 272                 return $this->toString();
 273         }
 274
 275         /**
 276          * Returns the message text as-is, only parameters are subsituted.
 277          * @return String: Unescaped untransformed message text.
 278          */
 279         public function plain() {
 280                 $this->format = 'plain';
 281                 return $this->toString();
 282         }
 283
 284         /**
 285          * Returns the parsed message text which is always surrounded by a block element.
 286          * @return String: HTML
 287          */
 288         public function parseAsBlock() {
 289                 $this->format = 'block-parse';
 290                 return $this->toString();
 291         }
 292
 293         /**
 294          * Returns the message text. {{-transformation is done and the result
 295          * is escaped excluding any raw parameters.
 296          * @return String: Escaped message text.
 297          */
 298         public function escaped() {
 299                 $this->format = 'escaped';
 300                 return $this->toString();
 301         }
 302
 303         /**
 304          * Check whether a message key has been defined currently.
 305          * @return Bool: true if it is and false if not.
 306          */
 307         public function exists() {
 308                 return $this->fetchMessage() !== false;
 309         }
 310
 311         public static function rawParam( $value ) {
 312                 return array( 'raw' => $value );
 313         }
 314
 315         /**
 316          * Substitutes any paramaters into the message text.
 317          * @param $message String, the message text
 318          * @param $type String: either before or after
 319          * @return String
 320          */
 321         protected function replaceParameters( $message, $type = 'before' ) {
 322                 $replacementKeys = array();
 323                 foreach( $this->parameters as $n => $param ) {
 324                         if ( $type === 'before' && !is_array( $param ) ) {
 325                                 $replacementKeys['$' . ($n + 1)] = $param;
 326                         } elseif ( $type === 'after' && isset( $param['raw'] ) ) {
 327                                 $replacementKeys['$' . ($n + 1)] = $param['raw'];
 328                         }
 329                 }
 330                 $message = strtr( $message, $replacementKeys );
 331                 return $message;
 332         }
 333
 334         /**
 335          * Wrapper for what ever method we use to parse wikitext.
 336          * @param $string String: Wikitext message contents
 337          * @return Wikitext parsed into HTML
 338          */
 339         protected function parseText( $string ) {
 340                 global $wgOut;
 341                 return $wgOut->parse( $string, /*linestart*/true, $this->interface, $this->language );
 342         }
 343
 344         /**
 345          * Wrapper for what ever method we use to {{-transform wikitext.
 346          * @param $string String: Wikitext message contents
 347          * @return Wikitext with {{-constructs replaced with their values.
 348          */
 349         protected function transformText( $string ) {
 350                 global $wgMessageCache;
 351                 return $wgMessageCache->transform( $string, $this->interface, $this->language );
 352         }
 353
 354         /**
 355          * Returns the textual value for the message.
 356          * @return Message contents or placeholder
 357          */
 358         protected function getMessageText() {
 359                 $message = $this->fetchMessage();
 360                 if ( $message === false ) {
 361                         return '&lt;' . htmlspecialchars( is_array($this->key) ? $this->key[0] : $this->key ) . '&gt;';
 362                 } else {
 363                         return $message;
 364                 }
 365         }
 366
 367         /**
 368          * Wrapper for what ever method we use to get message contents
 369          */
 370         protected function fetchMessage() {
 371                 if ( !isset( $this->message ) ) {
 372                         global $wgMessageCache;
 373                         if ( is_array($this->key) ) {
 374                                 foreach ( $this->key as $key ) {
 375                                         $message = $wgMessageCache->get( $key, $this->useDatabase, $this->language );
 376                                         if ( $message !== false && $message !== '' ) {
 377                                                 break;
 378                                         }
 379                                 }
 380                                 $this->message = $message;
 381                         } else {
 382                                 $this->message = $wgMessageCache->get( $this->key, $this->useDatabase, $this->language );
 383                         }
 384                 }
 385                 return $this->message;
 386         }
 387
 388 }