includes/linker/LinkRenderer.php

   1 <?php
   2 /**
   3  * This program is free software; you can redistribute it and/or modify
   4  * it under the terms of the GNU General Public License as published by
   5  * the Free Software Foundation; either version 2 of the License, or
   6  * (at your option) any later version.
   7  *
   8  * This program is distributed in the hope that it will be useful,
   9  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  10  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
  11  * GNU General Public License for more details.
  12  *
  13  * You should have received a copy of the GNU General Public License along
  14  * with this program; if not, write to the Free Software Foundation, Inc.,
  15  * 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301, USA.
  16  * http://www.gnu.org/copyleft/gpl.html
  17  *
  18  * @file
  19  * @license GPL-2.0+
  20  * @author Kunal Mehta <legoktm@member.fsf.org>
  21  */
  22 namespace MediaWiki\Linker;
  23
  24 use DummyLinker;
  25 use Hooks;
  26 use Html;
  27 use HtmlArmor;
  28 use Linker;
  29 use MediaWiki\MediaWikiServices;
  30 use Sanitizer;
  31 use Title;
  32 use TitleFormatter;
  33
  34 /**
  35  * Class that generates HTML <a> links for pages.
  36  *
  37  * @since 1.28
  38  */
  39 class LinkRenderer {
  40
  41         /**
  42          * Whether to force the pretty article path
  43          *
  44          * @var bool
  45          */
  46         private $forceArticlePath = false;
  47
  48         /**
  49          * A PROTO_* constant or false
  50          *
  51          * @var string|bool|int
  52          */
  53         private $expandUrls = false;
  54
  55         /**
  56          * Whether extra classes should be added
  57          *
  58          * @var bool
  59          */
  60         private $noClasses = false;
  61
  62         /**
  63          * @var int
  64          */
  65         private $stubThreshold = 0;
  66
  67         /**
  68          * @var TitleFormatter
  69          */
  70         private $titleFormatter;
  71
  72         /**
  73          * Whether to run the legacy Linker hooks
  74          *
  75          * @var bool
  76          */
  77         private $runLegacyBeginHook = true;
  78
  79         /**
  80          * @param TitleFormatter $titleFormatter
  81          */
  82         public function __construct( TitleFormatter $titleFormatter ) {
  83                 $this->titleFormatter = $titleFormatter;
  84         }
  85
  86         /**
  87          * @param bool $force
  88          */
  89         public function setForceArticlePath( $force ) {
  90                 $this->forceArticlePath = $force;
  91         }
  92
  93         /**
  94          * @return bool
  95          */
  96         public function getForceArticlePath() {
  97                 return $this->forceArticlePath;
  98         }
  99
 100         /**
 101          * @param string|bool|int $expand A PROTO_* constant or false
 102          */
 103         public function setExpandURLs( $expand ) {
 104                 $this->expandUrls = $expand;
 105         }
 106
 107         /**
 108          * @return string|bool|int a PROTO_* constant or false
 109          */
 110         public function getExpandURLs() {
 111                 return $this->expandUrls;
 112         }
 113
 114         /**
 115          * @param bool $no
 116          */
 117         public function setNoClasses( $no ) {
 118                 $this->noClasses = $no;
 119         }
 120
 121         /**
 122          * @return bool
 123          */
 124         public function getNoClasses() {
 125                 return $this->noClasses;
 126         }
 127
 128         /**
 129          * @param int $threshold
 130          */
 131         public function setStubThreshold( $threshold ) {
 132                 $this->stubThreshold = $threshold;
 133         }
 134
 135         /**
 136          * @return int
 137          */
 138         public function getStubThreshold() {
 139                 return $this->stubThreshold;
 140         }
 141
 142         /**
 143          * @param bool $run
 144          */
 145         public function setRunLegacyBeginHook( $run ) {
 146                 $this->runLegacyBeginHook = $run;
 147         }
 148
 149         /**
 150          * @param LinkTarget $target
 151          * @param string|HtmlArmor|null $text
 152          * @param array $extraAttribs
 153          * @param array $query
 154          * @return string
 155          */
 156         public function makeLink(
 157                 LinkTarget $target, $text = null, array $extraAttribs = [], array $query = []
 158         ) {
 159                 $title = Title::newFromLinkTarget( $target );
 160                 if ( $title->isKnown() ) {
 161                         return $this->makeKnownLink( $target, $text, $extraAttribs, $query );
 162                 } else {
 163                         return $this->makeBrokenLink( $target, $text, $extraAttribs, $query );
 164                 }
 165         }
 166
 167         /**
 168          * Get the options in the legacy format
 169          *
 170          * @param bool $isKnown Whether the link is known or broken
 171          * @return array
 172          */
 173         private function getLegacyOptions( $isKnown ) {
 174                 $options = [ 'stubThreshold' => $this->stubThreshold ];
 175                 if ( $this->noClasses ) {
 176                         $options[] = 'noclasses';
 177                 }
 178                 if ( $this->forceArticlePath ) {
 179                         $options[] = 'forcearticlepath';
 180                 }
 181                 if ( $this->expandUrls === PROTO_HTTP ) {
 182                         $options[] = 'http';
 183                 } elseif ( $this->expandUrls === PROTO_HTTPS ) {
 184                         $options[] = 'https';
 185                 }
 186
 187                 $options[] = $isKnown ? 'known' : 'broken';
 188
 189                 return $options;
 190         }
 191
 192         private function runBeginHook( LinkTarget $target, &$text, &$extraAttribs, &$query, $isKnown ) {
 193                 $ret = null;
 194                 if ( !Hooks::run( 'HtmlPageLinkRendererBegin',
 195                         [ $this, $target, &$text, &$extraAttribs, &$query, &$ret ] )
 196                 ) {
 197                         return $ret;
 198                 }
 199
 200                 // Now run the legacy hook
 201                 return $this->runLegacyBeginHook( $target, $text, $extraAttribs, $query, $isKnown );
 202         }
 203
 204         private function runLegacyBeginHook( LinkTarget $target, &$text, &$extraAttribs, &$query,
 205                 $isKnown
 206         ) {
 207                 if ( !$this->runLegacyBeginHook || !Hooks::isRegistered( 'LinkBegin' ) ) {
 208                         // Disabled, or nothing registered
 209                         return null;
 210                 }
 211
 212                 $realOptions = $options = $this->getLegacyOptions( $isKnown );
 213                 $ret = null;
 214                 $dummy = new DummyLinker();
 215                 $title = Title::newFromLinkTarget( $target );
 216                 $realHtml = $html = HtmlArmor::getHtml( $text );
 217                 if ( !Hooks::run( 'LinkBegin',
 218                         [ $dummy, $title, &$html, &$extraAttribs, &$query, &$options, &$ret ] )
 219                 ) {
 220                         return $ret;
 221                 }
 222
 223                 if ( $html !== null && $html !== $realHtml ) {
 224                         // &$html was modified, so re-armor it as $text
 225                         $text = new HtmlArmor( $html );
 226                 }
 227
 228                 // Check if they changed any of the options, hopefully not!
 229                 if ( $options !== $realOptions ) {
 230                         $factory = MediaWikiServices::getInstance()->getLinkRendererFactory();
 231                         // They did, so create a separate instance and have that take over the rest
 232                         $newRenderer = $factory->createFromLegacyOptions( $options );
 233                         // Don't recurse the hook...
 234                         $newRenderer->setRunLegacyBeginHook( false );
 235                         if ( in_array( 'known', $options, true ) ) {
 236                                 return $newRenderer->makeKnownLink( $title, $text, $extraAttribs, $query );
 237                         } elseif ( in_array( 'broken', $options, true ) ) {
 238                                 return $newRenderer->makeBrokenLink( $title, $text, $extraAttribs, $query );
 239                         } else {
 240                                 return $newRenderer->makeLink( $title, $text, $extraAttribs, $query );
 241                         }
 242                 }
 243
 244                 return null;
 245         }
 246
 247         /**
 248          * @param LinkTarget $target
 249          * @param string|HtmlArmor|null $text
 250          * @param array $extraAttribs
 251          * @param array $query
 252          * @return string
 253          */
 254         public function makeKnownLink(
 255                 LinkTarget $target, $text = null, array $extraAttribs = [], array $query = []
 256         ) {
 257                 // Run begin hook
 258                 $ret = $this->runBeginHook( $target, $text, $extraAttribs, $query, true );
 259                 if ( $ret !== null ) {
 260                         return $ret;
 261                 }
 262                 $target = $this->normalizeTarget( $target );
 263                 $url = $this->getLinkURL( $target, $query );
 264                 $attribs = [];
 265                 if ( !$this->noClasses ) {
 266                         $classes = [];
 267                         if ( $target->isExternal() ) {
 268                                 $classes[] = 'extiw';
 269                         }
 270                         $title = Title::newFromLinkTarget( $target );
 271                         $colour = Linker::getLinkColour( $title, $this->stubThreshold );
 272                         if ( $colour !== '' ) {
 273                                 $classes[] = $colour;
 274                         }
 275                         if ( $classes ) {
 276                                 $attribs['class'] = implode( ' ', $classes );
 277                         }
 278                 }
 279
 280                 $prefixedText = $this->titleFormatter->getPrefixedText( $target );
 281                 if ( $prefixedText !== '' ) {
 282                         $attribs['title'] = $prefixedText;
 283                 }
 284
 285                 $attribs = [
 286                         'href' => $url,
 287                 ] + $this->mergeAttribs( $attribs, $extraAttribs );
 288
 289                 if ( $text === null ) {
 290                         $text = $this->getLinkText( $target );
 291                 }
 292
 293                 return $this->buildAElement( $target, $text, $attribs, true );
 294         }
 295
 296         /**
 297          * @param LinkTarget $target
 298          * @param string|HtmlArmor|null $text
 299          * @param array $extraAttribs
 300          * @param array $query
 301          * @return string
 302          */
 303         public function makeBrokenLink(
 304                 LinkTarget $target, $text = null, array $extraAttribs = [], array $query = []
 305         ) {
 306                 // Run legacy hook
 307                 $ret = $this->runBeginHook( $target, $text, $extraAttribs, $query, false );
 308                 if ( $ret !== null ) {
 309                         return $ret;
 310                 }
 311
 312                 # We don't want to include fragments for broken links, because they
 313                 # generally make no sense.
 314                 if ( $target->hasFragment() ) {
 315                         $target = $target->createFragmentTarget( '' );
 316                 }
 317                 $target = $this->normalizeTarget( $target );
 318
 319                 if ( !isset( $query['action'] ) && $target->getNamespace() !== NS_SPECIAL ) {
 320                         $query['action'] = 'edit';
 321                         $query['redlink'] = '1';
 322                 }
 323
 324                 $url = $this->getLinkURL( $target, $query );
 325                 $attribs = $this->noClasses ? [] : [ 'class' => 'new' ];
 326                 $prefixedText = $this->titleFormatter->getPrefixedText( $target );
 327                 if ( $prefixedText !== '' ) {
 328                         // This ends up in parser cache!
 329                         $attribs['title'] = wfMessage( 'red-link-title', $prefixedText )
 330                                 ->inContentLanguage()
 331                                 ->text();
 332                 }
 333
 334                 $attribs = [
 335                         'href' => $url,
 336                 ] + $this->mergeAttribs( $attribs, $extraAttribs );
 337
 338                 if ( $text === null ) {
 339                         $text = $this->getLinkText( $target );
 340                 }
 341
 342                 return $this->buildAElement( $target, $text, $attribs, false );
 343         }
 344
 345         /**
 346          * Builds the final <a> element
 347          *
 348          * @param LinkTarget $target
 349          * @param string|HtmlArmor $text
 350          * @param array $attribs
 351          * @param bool $isKnown
 352          * @return null|string
 353          */
 354         private function buildAElement( LinkTarget $target, $text, array $attribs, $isKnown ) {
 355                 $ret = null;
 356                 if ( !Hooks::run( 'HtmlPageLinkRendererEnd',
 357                         [ $this, $target, $isKnown, &$text, &$attribs, &$ret ] )
 358                 ) {
 359                         return $ret;
 360                 }
 361
 362                 $html = HtmlArmor::getHtml( $text );
 363
 364                 // Run legacy hook
 365                 if ( Hooks::isRegistered( 'LinkEnd' ) ) {
 366                         $dummy = new DummyLinker();
 367                         $title = Title::newFromLinkTarget( $target );
 368                         $options = $this->getLegacyOptions( $isKnown );
 369                         if ( !Hooks::run( 'LinkEnd',
 370                                 [ $dummy, $title, $options, &$html, &$attribs, &$ret ] )
 371                         ) {
 372                                 return $ret;
 373                         }
 374                 }
 375
 376                 return Html::rawElement( 'a', $attribs, $html );
 377         }
 378
 379         /**
 380          * @param LinkTarget $target
 381          * @return string non-escaped text
 382          */
 383         private function getLinkText( LinkTarget $target ) {
 384                 $prefixedText = $this->titleFormatter->getPrefixedText( $target );
 385                 // If the target is just a fragment, with no title, we return the fragment
 386                 // text.  Otherwise, we return the title text itself.
 387                 if ( $prefixedText === '' && $target->hasFragment() ) {
 388                         return $target->getFragment();
 389                 }
 390
 391                 return $prefixedText;
 392         }
 393
 394         private function getLinkURL( LinkTarget $target, array $query = [] ) {
 395                 // TODO: Use a LinkTargetResolver service instead of Title
 396                 $title = Title::newFromLinkTarget( $target );
 397                 $proto = $this->expandUrls !== false
 398                         ? $this->expandUrls
 399                         : PROTO_RELATIVE;
 400                 if ( $this->forceArticlePath ) {
 401                         $realQuery = $query;
 402                         $query = [];
 403                 } else {
 404                         $realQuery = [];
 405                 }
 406                 $url = $title->getLinkURL( $query, false, $proto );
 407
 408                 if ( $this->forceArticlePath && $realQuery ) {
 409                         $url = wfAppendQuery( $url, $realQuery );
 410                 }
 411
 412                 return $url;
 413         }
 414
 415         /**
 416          * Normalizes the provided target
 417          *
 418          * @todo move the code from Linker actually here
 419          * @param LinkTarget $target
 420          * @return LinkTarget
 421          */
 422         private function normalizeTarget( LinkTarget $target ) {
 423                 return Linker::normaliseSpecialPage( $target );
 424         }
 425
 426         /**
 427          * Merges two sets of attributes
 428          *
 429          * @param array $defaults
 430          * @param array $attribs
 431          *
 432          * @return array
 433          */
 434         private function mergeAttribs( $defaults, $attribs ) {
 435                 if ( !$attribs ) {
 436                         return $defaults;
 437                 }
 438                 # Merge the custom attribs with the default ones, and iterate
 439                 # over that, deleting all "false" attributes.
 440                 $ret = [];
 441                 $merged = Sanitizer::mergeAttributes( $defaults, $attribs );
 442                 foreach ( $merged as $key => $val ) {
 443                         # A false value suppresses the attribute
 444                         if ( $val !== false ) {
 445                                 $ret[$key] = $val;
 446                         }
 447                 }
 448                 return $ret;
 449         }
 450
 451 }