_source/plugins/undo/plugin.js

   1 /*\r
   2 Copyright (c) 2003-2010, CKSource - Frederico Knabben. All rights reserved.\r
   3 For licensing, see LICENSE.html or http://ckeditor.com/license\r
   4 */\r
   5 \r
   6 /**\r
   7  * @fileOverview Undo/Redo system for saving shapshot for document modification\r
   8  *              and other recordable changes.\r
   9  */\r
  10 \r
  11 (function()\r
  12 {\r
  13         CKEDITOR.plugins.add( 'undo',\r
  14         {\r
  15                 requires : [ 'selection', 'wysiwygarea' ],\r
  16 \r
  17                 init : function( editor )\r
  18                 {\r
  19                         var undoManager = new UndoManager( editor );\r
  20 \r
  21                         var undoCommand = editor.addCommand( 'undo',\r
  22                                 {\r
  23                                         exec : function()\r
  24                                         {\r
  25                                                 if ( undoManager.undo() )\r
  26                                                 {\r
  27                                                         editor.selectionChange();\r
  28                                                         this.fire( 'afterUndo' );\r
  29                                                 }\r
  30                                         },\r
  31                                         state : CKEDITOR.TRISTATE_DISABLED,\r
  32                                         canUndo : false\r
  33                                 });\r
  34 \r
  35                         var redoCommand = editor.addCommand( 'redo',\r
  36                                 {\r
  37                                         exec : function()\r
  38                                         {\r
  39                                                 if ( undoManager.redo() )\r
  40                                                 {\r
  41                                                         editor.selectionChange();\r
  42                                                         this.fire( 'afterRedo' );\r
  43                                                 }\r
  44                                         },\r
  45                                         state : CKEDITOR.TRISTATE_DISABLED,\r
  46                                         canUndo : false\r
  47                                 });\r
  48 \r
  49                         undoManager.onChange = function()\r
  50                         {\r
  51                                 undoCommand.setState( undoManager.undoable() ? CKEDITOR.TRISTATE_OFF : CKEDITOR.TRISTATE_DISABLED );\r
  52                                 redoCommand.setState( undoManager.redoable() ? CKEDITOR.TRISTATE_OFF : CKEDITOR.TRISTATE_DISABLED );\r
  53                         };\r
  54 \r
  55                         function recordCommand( event )\r
  56                         {\r
  57                                 // If the command hasn't been marked to not support undo.\r
  58                                 if ( undoManager.enabled && event.data.command.canUndo !== false )\r
  59                                         undoManager.save();\r
  60                         }\r
  61 \r
  62                         // We'll save snapshots before and after executing a command.\r
  63                         editor.on( 'beforeCommandExec', recordCommand );\r
  64                         editor.on( 'afterCommandExec', recordCommand );\r
  65 \r
  66                         // Save snapshots before doing custom changes.\r
  67                         editor.on( 'saveSnapshot', function()\r
  68                                 {\r
  69                                         undoManager.save();\r
  70                                 });\r
  71 \r
  72                         // Registering keydown on every document recreation.(#3844)\r
  73                         editor.on( 'contentDom', function()\r
  74                                 {\r
  75                                         editor.document.on( 'keydown', function( event )\r
  76                                                 {\r
  77                                                         // Do not capture CTRL hotkeys.\r
  78                                                         if ( !event.data.$.ctrlKey && !event.data.$.metaKey )\r
  79                                                                 undoManager.type( event );\r
  80                                                 });\r
  81                                 });\r
  82 \r
  83                         // Always save an undo snapshot - the previous mode might have\r
  84                         // changed editor contents.\r
  85                         editor.on( 'beforeModeUnload', function()\r
  86                                 {\r
  87                                         editor.mode == 'wysiwyg' && undoManager.save( true );\r
  88                                 });\r
  89 \r
  90                         // Make the undo manager available only in wysiwyg mode.\r
  91                         editor.on( 'mode', function()\r
  92                                 {\r
  93                                         undoManager.enabled = editor.mode == 'wysiwyg';\r
  94                                         undoManager.onChange();\r
  95                                 });\r
  96 \r
  97                         editor.ui.addButton( 'Undo',\r
  98                                 {\r
  99                                         label : editor.lang.undo,\r
 100                                         command : 'undo'\r
 101                                 });\r
 102 \r
 103                         editor.ui.addButton( 'Redo',\r
 104                                 {\r
 105                                         label : editor.lang.redo,\r
 106                                         command : 'redo'\r
 107                                 });\r
 108 \r
 109                         editor.resetUndo = function()\r
 110                         {\r
 111                                 // Reset the undo stack.\r
 112                                 undoManager.reset();\r
 113 \r
 114                                 // Create the first image.\r
 115                                 editor.fire( 'saveSnapshot' );\r
 116                         };\r
 117                 }\r
 118         });\r
 119 \r
 120         // Gets a snapshot image which represent the current document status.\r
 121         function Image( editor )\r
 122         {\r
 123                 var selection = editor.getSelection();\r
 124 \r
 125                 this.contents   = editor.getSnapshot();\r
 126                 this.bookmarks  = selection && selection.createBookmarks2( true );\r
 127 \r
 128                 // In IE, we need to remove the expando attributes.\r
 129                 if ( CKEDITOR.env.ie )\r
 130                         this.contents = this.contents.replace( /\s+_cke_expando=".*?"/g, '' );\r
 131         }\r
 132 \r
 133         // Attributes that browser may changing them when setting via innerHTML.\r
 134         var protectedAttrs = /\b(?:href|src|name)="[^"]*?"/gi;\r
 135 \r
 136         Image.prototype =\r
 137         {\r
 138                 equals : function( otherImage, contentOnly )\r
 139                 {\r
 140                         var thisContents = this.contents,\r
 141                                 otherContents = otherImage.contents;\r
 142 \r
 143                         // For IE6/7 : Comparing only the protected attribute values but not the original ones.(#4522)\r
 144                         if( CKEDITOR.env.ie && ( CKEDITOR.env.ie7Compat || CKEDITOR.env.ie6Compat ) )\r
 145                         {\r
 146                                 thisContents = thisContents.replace( protectedAttrs, '' );\r
 147                                 otherContents = otherContents.replace( protectedAttrs, '' );\r
 148                         }\r
 149 \r
 150                         if( thisContents != otherContents )\r
 151                                 return false;\r
 152 \r
 153                         if ( contentOnly )\r
 154                                 return true;\r
 155 \r
 156                         var bookmarksA = this.bookmarks,\r
 157                                 bookmarksB = otherImage.bookmarks;\r
 158 \r
 159                         if ( bookmarksA || bookmarksB )\r
 160                         {\r
 161                                 if ( !bookmarksA || !bookmarksB || bookmarksA.length != bookmarksB.length )\r
 162                                         return false;\r
 163 \r
 164                                 for ( var i = 0 ; i < bookmarksA.length ; i++ )\r
 165                                 {\r
 166                                         var bookmarkA = bookmarksA[ i ],\r
 167                                                 bookmarkB = bookmarksB[ i ];\r
 168 \r
 169                                         if (\r
 170                                                 bookmarkA.startOffset != bookmarkB.startOffset ||\r
 171                                                 bookmarkA.endOffset != bookmarkB.endOffset ||\r
 172                                                 !CKEDITOR.tools.arrayCompare( bookmarkA.start, bookmarkB.start ) ||\r
 173                                                 !CKEDITOR.tools.arrayCompare( bookmarkA.end, bookmarkB.end ) )\r
 174                                         {\r
 175                                                 return false;\r
 176                                         }\r
 177                                 }\r
 178                         }\r
 179 \r
 180                         return true;\r
 181                 }\r
 182         };\r
 183 \r
 184         /**\r
 185          * @constructor Main logic for Redo/Undo feature.\r
 186          */\r
 187         function UndoManager( editor )\r
 188         {\r
 189                 this.editor = editor;\r
 190 \r
 191                 // Reset the undo stack.\r
 192                 this.reset();\r
 193         }\r
 194 \r
 195 \r
 196         var editingKeyCodes = { /*Backspace*/ 8:1, /*Delete*/ 46:1 },\r
 197                 modifierKeyCodes = { /*Shift*/ 16:1, /*Ctrl*/ 17:1, /*Alt*/ 18:1 },\r
 198                 navigationKeyCodes = { 37:1, 38:1, 39:1, 40:1 };  // Arrows: L, T, R, B\r
 199 \r
 200         UndoManager.prototype =\r
 201         {\r
 202                 /**\r
 203                  * Process undo system regard keystrikes.\r
 204                  * @param {CKEDITOR.dom.event} event\r
 205                  */\r
 206                 type : function( event )\r
 207                 {\r
 208                         var keystroke = event && event.data.getKey(),\r
 209                                 isModifierKey = keystroke in modifierKeyCodes,\r
 210                                 isEditingKey = keystroke in editingKeyCodes,\r
 211                                 wasEditingKey = this.lastKeystroke in editingKeyCodes,\r
 212                                 sameAsLastEditingKey = isEditingKey && keystroke == this.lastKeystroke,\r
 213                                 // Keystrokes which navigation through contents.\r
 214                                 isReset = keystroke in navigationKeyCodes,\r
 215                                 wasReset = this.lastKeystroke in navigationKeyCodes,\r
 216 \r
 217                                 // Keystrokes which just introduce new contents.\r
 218                                 isContent = ( !isEditingKey && !isReset ),\r
 219 \r
 220                                 // Create undo snap for every different modifier key.\r
 221                                 modifierSnapshot = ( isEditingKey && !sameAsLastEditingKey ),\r
 222                                 // Create undo snap on the following cases:\r
 223                                 // 1. Just start to type .\r
 224                                 // 2. Typing some content after a modifier.\r
 225                                 // 3. Typing some content after make a visible selection.\r
 226                                 startedTyping = !( isModifierKey || this.typing )\r
 227                                         || ( isContent && ( wasEditingKey || wasReset ) );\r
 228 \r
 229                         if ( startedTyping || modifierSnapshot )\r
 230                         {\r
 231                                 var beforeTypeImage = new Image( this.editor );\r
 232 \r
 233                                 // Use setTimeout, so we give the necessary time to the\r
 234                                 // browser to insert the character into the DOM.\r
 235                                 CKEDITOR.tools.setTimeout( function()\r
 236                                         {\r
 237                                                 var currentSnapshot = this.editor.getSnapshot();\r
 238 \r
 239                                                 // In IE, we need to remove the expando attributes.\r
 240                                                 if ( CKEDITOR.env.ie )\r
 241                                                         currentSnapshot = currentSnapshot.replace( /\s+_cke_expando=".*?"/g, '' );\r
 242 \r
 243                                                 if ( beforeTypeImage.contents != currentSnapshot )\r
 244                                                 {\r
 245                                                         // It's safe to now indicate typing state.\r
 246                                                         this.typing = true;\r
 247 \r
 248                                                         // This's a special save, with specified snapshot\r
 249                                                         // and without auto 'fireChange'.\r
 250                                                         if ( !this.save( false, beforeTypeImage, false ) )\r
 251                                                                 // Drop future snapshots.\r
 252                                                                 this.snapshots.splice( this.index + 1, this.snapshots.length - this.index - 1 );\r
 253 \r
 254                                                         this.hasUndo = true;\r
 255                                                         this.hasRedo = false;\r
 256 \r
 257                                                         this.typesCount = 1;\r
 258                                                         this.modifiersCount = 1;\r
 259 \r
 260                                                         this.onChange();\r
 261                                                 }\r
 262                                         },\r
 263                                         0, this\r
 264                                 );\r
 265                         }\r
 266 \r
 267                         this.lastKeystroke = keystroke;\r
 268 \r
 269                         // Create undo snap after typed too much (over 25 times).\r
 270                         if ( isEditingKey )\r
 271                         {\r
 272                                 this.typesCount = 0;\r
 273                                 this.modifiersCount++;\r
 274 \r
 275                                 if ( this.modifiersCount > 25 )\r
 276                                 {\r
 277                                         this.save( false, null, false );\r
 278                                         this.modifiersCount = 1;\r
 279                                 }\r
 280                         }\r
 281                         else if ( !isReset )\r
 282                         {\r
 283                                 this.modifiersCount = 0;\r
 284                                 this.typesCount++;\r
 285 \r
 286                                 if ( this.typesCount > 25 )\r
 287                                 {\r
 288                                         this.save( false, null, false );\r
 289                                         this.typesCount = 1;\r
 290                                 }\r
 291                         }\r
 292 \r
 293                 },\r
 294 \r
 295                 reset : function()      // Reset the undo stack.\r
 296                 {\r
 297                         /**\r
 298                          * Remember last pressed key.\r
 299                          */\r
 300                         this.lastKeystroke = 0;\r
 301 \r
 302                         /**\r
 303                          * Stack for all the undo and redo snapshots, they're always created/removed\r
 304                          * in consistency.\r
 305                          */\r
 306                         this.snapshots = [];\r
 307 \r
 308                         /**\r
 309                          * Current snapshot history index.\r
 310                          */\r
 311                         this.index = -1;\r
 312 \r
 313                         this.limit = this.editor.config.undoStackSize;\r
 314 \r
 315                         this.currentImage = null;\r
 316 \r
 317                         this.hasUndo = false;\r
 318                         this.hasRedo = false;\r
 319 \r
 320                         this.resetType();\r
 321                 },\r
 322 \r
 323                 /**\r
 324                  * Reset all states about typing.\r
 325                  * @see  UndoManager.type\r
 326                  */\r
 327                 resetType : function()\r
 328                 {\r
 329                         this.typing = false;\r
 330                         delete this.lastKeystroke;\r
 331                         this.typesCount = 0;\r
 332                         this.modifiersCount = 0;\r
 333                 },\r
 334                 fireChange : function()\r
 335                 {\r
 336                         this.hasUndo = !!this.getNextImage( true );\r
 337                         this.hasRedo = !!this.getNextImage( false );\r
 338                         // Reset typing\r
 339                         this.resetType();\r
 340                         this.onChange();\r
 341                 },\r
 342 \r
 343                 /**\r
 344                  * Save a snapshot of document image for later retrieve.\r
 345                  */\r
 346                 save : function( onContentOnly, image, autoFireChange )\r
 347                 {\r
 348                         var snapshots = this.snapshots;\r
 349 \r
 350                         // Get a content image.\r
 351                         if ( !image )\r
 352                                 image = new Image( this.editor );\r
 353 \r
 354                         // Check if this is a duplicate. In such case, do nothing.\r
 355                         if ( this.currentImage && image.equals( this.currentImage, onContentOnly ) )\r
 356                                 return false;\r
 357 \r
 358                         // Drop future snapshots.\r
 359                         snapshots.splice( this.index + 1, snapshots.length - this.index - 1 );\r
 360 \r
 361                         // If we have reached the limit, remove the oldest one.\r
 362                         if ( snapshots.length == this.limit )\r
 363                                 snapshots.shift();\r
 364 \r
 365                         // Add the new image, updating the current index.\r
 366                         this.index = snapshots.push( image ) - 1;\r
 367 \r
 368                         this.currentImage = image;\r
 369 \r
 370                         if ( autoFireChange !== false )\r
 371                                 this.fireChange();\r
 372                         return true;\r
 373                 },\r
 374 \r
 375                 restoreImage : function( image )\r
 376                 {\r
 377                         this.editor.loadSnapshot( image.contents );\r
 378 \r
 379                         if ( image.bookmarks )\r
 380                                 this.editor.getSelection().selectBookmarks( image.bookmarks );\r
 381                         else if ( CKEDITOR.env.ie )\r
 382                         {\r
 383                                 // IE BUG: If I don't set the selection to *somewhere* after setting\r
 384                                 // document contents, then IE would create an empty paragraph at the bottom\r
 385                                 // the next time the document is modified.\r
 386                                 var $range = this.editor.document.getBody().$.createTextRange();\r
 387                                 $range.collapse( true );\r
 388                                 $range.select();\r
 389                         }\r
 390 \r
 391                         this.index = image.index;\r
 392 \r
 393                         this.currentImage = image;\r
 394 \r
 395                         this.fireChange();\r
 396                 },\r
 397 \r
 398                 // Get the closest available image.\r
 399                 getNextImage : function( isUndo )\r
 400                 {\r
 401                         var snapshots = this.snapshots,\r
 402                                 currentImage = this.currentImage,\r
 403                                 image, i;\r
 404 \r
 405                         if ( currentImage )\r
 406                         {\r
 407                                 if ( isUndo )\r
 408                                 {\r
 409                                         for ( i = this.index - 1 ; i >= 0 ; i-- )\r
 410                                         {\r
 411                                                 image = snapshots[ i ];\r
 412                                                 if ( !currentImage.equals( image, true ) )\r
 413                                                 {\r
 414                                                         image.index = i;\r
 415                                                         return image;\r
 416                                                 }\r
 417                                         }\r
 418                                 }\r
 419                                 else\r
 420                                 {\r
 421                                         for ( i = this.index + 1 ; i < snapshots.length ; i++ )\r
 422                                         {\r
 423                                                 image = snapshots[ i ];\r
 424                                                 if ( !currentImage.equals( image, true ) )\r
 425                                                 {\r
 426                                                         image.index = i;\r
 427                                                         return image;\r
 428                                                 }\r
 429                                         }\r
 430                                 }\r
 431                         }\r
 432 \r
 433                         return null;\r
 434                 },\r
 435 \r
 436                 /**\r
 437                  * Check the current redo state.\r
 438                  * @return {Boolean} Whether the document has previous state to\r
 439                  *              retrieve.\r
 440                  */\r
 441                 redoable : function()\r
 442                 {\r
 443                         return this.enabled && this.hasRedo;\r
 444                 },\r
 445 \r
 446                 /**\r
 447                  * Check the current undo state.\r
 448                  * @return {Boolean} Whether the document has future state to restore.\r
 449                  */\r
 450                 undoable : function()\r
 451                 {\r
 452                         return this.enabled && this.hasUndo;\r
 453                 },\r
 454 \r
 455                 /**\r
 456                  * Perform undo on current index.\r
 457                  */\r
 458                 undo : function()\r
 459                 {\r
 460                         if ( this.undoable() )\r
 461                         {\r
 462                                 this.save( true );\r
 463 \r
 464                                 var image = this.getNextImage( true );\r
 465                                 if ( image )\r
 466                                         return this.restoreImage( image ), true;\r
 467                         }\r
 468 \r
 469                         return false;\r
 470                 },\r
 471 \r
 472                 /**\r
 473                  * Perform redo on current index.\r
 474                  */\r
 475                 redo : function()\r
 476                 {\r
 477                         if ( this.redoable() )\r
 478                         {\r
 479                                 // Try to save. If no changes have been made, the redo stack\r
 480                                 // will not change, so it will still be redoable.\r
 481                                 this.save( true );\r
 482 \r
 483                                 // If instead we had changes, we can't redo anymore.\r
 484                                 if ( this.redoable() )\r
 485                                 {\r
 486                                         var image = this.getNextImage( false );\r
 487                                         if ( image )\r
 488                                                 return this.restoreImage( image ), true;\r
 489                                 }\r
 490                         }\r
 491 \r
 492                         return false;\r
 493                 }\r
 494         };\r
 495 })();\r
 496 \r
 497 /**\r
 498  * The number of undo steps to be saved. The higher this setting value the more\r
 499  * memory is used for it.\r
 500  * @type Number\r
 501  * @default 20\r
 502  * @example\r
 503  * config.undoStackSize = 50;\r
 504  */\r
 505 CKEDITOR.config.undoStackSize = 20;\r