includes/changes/ChangesListFilter.php

   1 <?php
   2 /**
   3  * Represents a filter (used on ChangesListSpecialPage and descendants)
   4  *
   5  * This program is free software; you can redistribute it and/or modify
   6  * it under the terms of the GNU General Public License as published by
   7  * the Free Software Foundation; either version 2 of the License, or
   8  * (at your option) any later version.
   9  *
  10  * This program is distributed in the hope that it will be useful,
  11  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  12  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
  13  * GNU General Public License for more details.
  14  *
  15  * You should have received a copy of the GNU General Public License along
  16  * with this program; if not, write to the Free Software Foundation, Inc.,
  17  * 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301, USA.
  18  * http://www.gnu.org/copyleft/gpl.html
  19  *
  20  * @file
  21  * @license GPL 2+
  22  * @author Matthew Flaschen
  23  */
  24
  25 /**
  26  * Represents a filter (used on ChangesListSpecialPage and descendants)
  27  *
  28  * @since 1.29
  29  */
  30 abstract class ChangesListFilter {
  31         /**
  32          * Filter name
  33          *
  34          * @var string $name
  35          */
  36         protected $name;
  37
  38         /**
  39          * CSS class suffix used for attribution, e.g. 'bot'.
  40          *
  41          * In this example, if bot actions are included in the result set, this CSS class
  42          * will then be included in all bot-flagged actions.
  43          *
  44          * @var string|null $cssClassSuffix
  45          */
  46         protected $cssClassSuffix;
  47
  48         /**
  49          * Callable that returns true if and only if a row is attributed to this filter
  50          *
  51          * @var callable $isRowApplicableCallable
  52          */
  53         protected $isRowApplicableCallable;
  54
  55         /**
  56          * Group.  ChangesListFilterGroup this belongs to
  57          *
  58          * @var ChangesListFilterGroup $group
  59          */
  60         protected $group;
  61
  62         /**
  63          * i18n key of label for structured UI
  64          *
  65          * @var string $label
  66          */
  67         protected $label;
  68
  69         /**
  70          * i18n key of description for structured UI
  71          *
  72          * @var string $description
  73          */
  74         protected $description;
  75
  76         /**
  77          * List of conflicting groups
  78          *
  79          * @var array $conflictingGroups Array of associative arrays with conflict
  80          *   information.  See setUnidirectionalConflict
  81          */
  82         protected $conflictingGroups = [];
  83
  84         /**
  85          * List of conflicting filters
  86          *
  87          * @var array $conflictingFilters Array of associative arrays with conflict
  88          *   information.  See setUnidirectionalConflict
  89          */
  90         protected $conflictingFilters = [];
  91
  92         /**
  93          * List of filters that are a subset of the current filter
  94          *
  95          * @var array $subsetFilters Array of associative arrays with subset information
  96          */
  97         protected $subsetFilters = [];
  98
  99         /**
 100          * Priority integer.  Higher value means higher up in the group's filter list.
 101          *
 102          * @var string $priority
 103          */
 104         protected $priority;
 105
 106         const RESERVED_NAME_CHAR = '_';
 107
 108         /**
 109          * Creates a new filter with the specified configuration, and registers it to the
 110          * specified group.
 111          *
 112          * It infers which UI (it can be either or both) to display the filter on based on
 113          * which messages are provided.
 114          *
 115          * If 'label' is provided, it will be displayed on the structured UI.  Thus,
 116          * 'label', 'description', and sub-class parameters are optional depending on which
 117          * UI it's for.
 118          *
 119          * @param array $filterDefinition ChangesListFilter definition
 120          *
 121          * $filterDefinition['name'] string Name of filter; use lowercase with no
 122          *  punctuation
 123          * $filterDefinition['cssClassSuffix'] string CSS class suffix, used to mark
 124          *  that a particular row belongs to this filter (when a row is included by the
 125          *  filter) (optional)
 126          * $filterDefinition['isRowApplicableCallable'] Callable taking two parameters, the
 127          *  IContextSource, and the RecentChange object for the row, and returning true if
 128          *  the row is attributed to this filter.  The above CSS class will then be
 129          *  automatically added (optional, required if cssClassSuffix is used).
 130          * $filterDefinition['group'] ChangesListFilterGroup Group.  Filter group this
 131          *  belongs to.
 132          * $filterDefinition['label'] string i18n key of label for structured UI.
 133          * $filterDefinition['description'] string i18n key of description for structured
 134          *  UI.
 135          * $filterDefinition['priority'] int Priority integer.  Higher value means higher
 136          *  up in the group's filter list.
 137          */
 138         public function __construct( array $filterDefinition ) {
 139                 if ( isset( $filterDefinition['group'] ) ) {
 140                         $this->group = $filterDefinition['group'];
 141                 } else {
 142                         throw new MWException( 'You must use \'group\' to specify the ' .
 143                                 'ChangesListFilterGroup this filter belongs to' );
 144                 }
 145
 146                 if ( strpos( $filterDefinition['name'], self::RESERVED_NAME_CHAR ) !== false ) {
 147                         throw new MWException( 'Filter names may not contain \'' .
 148                                 self::RESERVED_NAME_CHAR .
 149                                 '\'.  Use the naming convention: \'lowercase\''
 150                         );
 151                 }
 152
 153                 if ( $this->group->getFilter( $filterDefinition['name'] ) ) {
 154                         throw new MWException( 'Two filters in a group cannot have the ' .
 155                                 "same name: '{$filterDefinition['name']}'" );
 156                 }
 157
 158                 $this->name = $filterDefinition['name'];
 159
 160                 if ( isset( $filterDefinition['cssClassSuffix'] ) ) {
 161                         $this->cssClassSuffix = $filterDefinition['cssClassSuffix'];
 162                         $this->isRowApplicableCallable = $filterDefinition['isRowApplicableCallable'];
 163                 }
 164
 165                 if ( isset( $filterDefinition['label'] ) ) {
 166                         $this->label = $filterDefinition['label'];
 167                         $this->description = $filterDefinition['description'];
 168                 }
 169
 170                 $this->priority = $filterDefinition['priority'];
 171
 172                 $this->group->registerFilter( $this );
 173         }
 174
 175         /**
 176          * Marks that the given ChangesListFilterGroup or ChangesListFilter conflicts with this object.
 177          *
 178          * WARNING: This means there is a conflict when both things are *shown*
 179          * (not filtered out), even for the hide-based filters.  So e.g. conflicting with
 180          * 'hideanons' means there is a conflict if only anonymous users are *shown*.
 181          *
 182          * @param ChangesListFilterGroup|ChangesListFilter $other Other
 183          *  ChangesListFilterGroup or ChangesListFilter
 184          * @param string $globalKey i18n key for top-level conflict message
 185          * @param string $forwardKey i18n key for conflict message in this
 186          *  direction (when in UI context of $this object)
 187          * @param string $backwardKey i18n key for conflict message in reverse
 188          *  direction (when in UI context of $other object)
 189          */
 190         public function conflictsWith( $other, $globalKey, $forwardKey,
 191                 $backwardKey ) {
 192
 193                 if ( $globalKey === null || $forwardKey === null ||
 194                         $backwardKey === null ) {
 195
 196                         throw new MWException( 'All messages must be specified' );
 197                 }
 198
 199                 $this->setUnidirectionalConflict(
 200                         $other,
 201                         $globalKey,
 202                         $forwardKey
 203                 );
 204
 205                 $other->setUnidirectionalConflict(
 206                         $this,
 207                         $globalKey,
 208                         $backwardKey
 209                 );
 210         }
 211
 212         /**
 213          * Marks that the given ChangesListFilterGroup or ChangesListFilter conflicts with
 214          * this object.
 215          *
 216          * Internal use ONLY.
 217          *
 218          * @param ChangesListFilterGroup|ChangesListFilter $other Other
 219          *  ChangesListFilterGroup or ChangesListFilter
 220          * @param string $globalDescription i18n key for top-level conflict message
 221          * @param string $contextDescription i18n key for conflict message in this
 222          *  direction (when in UI context of $this object)
 223          */
 224         public function setUnidirectionalConflict( $other, $globalDescription,
 225                 $contextDescription ) {
 226
 227                 if ( $other instanceof ChangesListFilterGroup ) {
 228                         $this->conflictingGroups[] = [
 229                                 'group' => $other->getName(),
 230                                 'globalDescription' => $globalDescription,
 231                                 'contextDescription' => $contextDescription,
 232                         ];
 233                 } elseif ( $other instanceof ChangesListFilter ) {
 234                         $this->conflictingFilters[] = [
 235                                 'group' => $other->getGroup()->getName(),
 236                                 'filter' => $other->getName(),
 237                                 'globalDescription' => $globalDescription,
 238                                 'contextDescription' => $contextDescription,
 239                         ];
 240                 } else {
 241                         throw new MWException( 'You can only pass in a ChangesListFilterGroup or a ChangesListFilter' );
 242                 }
 243         }
 244
 245         /**
 246          * Marks that the current instance is (also) a superset of the filter passed in.
 247          * This can be called more than once.
 248          *
 249          * This means that anything in the results for the other filter is also in the
 250          * results for this one.
 251          *
 252          * @param ChangesListFilter The filter the current instance is a superset of
 253          */
 254         public function setAsSupersetOf( ChangesListFilter $other ) {
 255                 if ( $other->getGroup() !== $this->getGroup() ) {
 256                         throw new MWException( 'Supersets can only be defined for filters in the same group' );
 257                 }
 258
 259                 $this->subsetFilters[] = [
 260                         // It's always the same group, but this makes the representation
 261                         // more consistent with conflicts.
 262                         'group' => $other->getGroup()->getName(),
 263                         'filter' => $other->getName(),
 264                 ];
 265         }
 266
 267         /**
 268          * @return string Name, e.g. hideanons
 269          */
 270         public function getName() {
 271                 return $this->name;
 272         }
 273
 274         /**
 275          * @return ChangesListFilterGroup Group this belongs to
 276          */
 277         public function getGroup() {
 278                 return $this->group;
 279         }
 280
 281         /**
 282          * @return string i18n key of label for structured UI
 283          */
 284         public function getLabel() {
 285                 return $this->label;
 286         }
 287
 288         /**
 289          * @return string i18n key of description for structured UI
 290          */
 291         public function getDescription() {
 292                 return $this->description;
 293         }
 294
 295         /**
 296          * Checks whether the filter should display on the unstructured UI
 297          *
 298          * @return bool Whether to display
 299          */
 300         abstract public function displaysOnUnstructuredUi();
 301
 302         /**
 303          * Checks whether the filter should display on the structured UI
 304          * This refers to the exact filter.  See also isFeatureAvailableOnStructuredUi.
 305          *
 306          * @return bool Whether to display
 307          */
 308         public function displaysOnStructuredUi() {
 309                 return $this->label !== null;
 310         }
 311
 312         /**
 313          * Checks whether an equivalent feature for this filter is available on the
 314          * structured UI.
 315          *
 316          * This can either be the exact filter, or a new filter that replaces it.
 317          */
 318         public function isFeatureAvailableOnStructuredUi() {
 319                 return $this->displaysOnStructuredUi();
 320         }
 321
 322         /**
 323          * @return int Priority.  Higher value means higher up in the group list
 324          */
 325         public function getPriority() {
 326                 return $this->priority;
 327         }
 328
 329         /**
 330          * Gets the CSS class
 331          *
 332          * @return string|null CSS class, or null if not defined
 333          */
 334         protected function getCssClass() {
 335                 if ( $this->cssClassSuffix !== null ) {
 336                         return ChangesList::CSS_CLASS_PREFIX . $this->cssClassSuffix;
 337                 } else {
 338                         return null;
 339                 }
 340         }
 341
 342         /**
 343          * Add CSS class if needed
 344          *
 345          * @param IContextSource $ctx Context source
 346          * @param RecentChange $rc Recent changes object
 347          * @param Non-associative array of CSS class names; appended to if needed
 348          */
 349         public function applyCssClassIfNeeded( IContextSource $ctx, RecentChange $rc, array &$classes ) {
 350                 if ( $this->isRowApplicableCallable === null ) {
 351                         return;
 352                 }
 353
 354                 if ( call_user_func( $this->isRowApplicableCallable, $ctx, $rc ) ) {
 355                         $classes[] = $this->getCssClass();
 356                 }
 357         }
 358
 359         /**
 360          * Gets the JS data required by the front-end of the structured UI
 361          *
 362          * @return array Associative array Data required by the front-end.  messageKeys is
 363          *  a special top-level value, with the value being an array of the message keys to
 364          *  send to the client.
 365          */
 366         public function getJsData() {
 367                 $output = [
 368                         'name' => $this->getName(),
 369                         'label' => $this->getLabel(),
 370                         'description' => $this->getDescription(),
 371                         'cssClass' => $this->getCssClass(),
 372                         'priority' => $this->priority,
 373                         'subset' => $this->subsetFilters,
 374                         'conflicts' => [],
 375                 ];
 376
 377                 $output['messageKeys'] = [
 378                         $this->getLabel(),
 379                         $this->getDescription(),
 380                 ];
 381
 382                 $conflicts = array_merge(
 383                         $this->conflictingGroups,
 384                         $this->conflictingFilters
 385                 );
 386
 387                 foreach ( $conflicts as $conflictInfo ) {
 388                         $output['conflicts'][] = $conflictInfo;
 389                         array_push(
 390                                 $output['messageKeys'],
 391                                 $conflictInfo['globalDescription'],
 392                                 $conflictInfo['contextDescription']
 393                         );
 394                 }
 395
 396                 return $output;
 397         }
 398 }