includes/Message.php

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