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