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domconverter.js 21 KB

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  1. /**
  2. * @license Copyright (c) 2003-2015, CKSource - Frederico Knabben. All rights reserved.
  3. * For licensing, see LICENSE.md.
  4. */
  5. 'use strict';
  6. import ViewText from './text.js';
  7. import ViewElement from './element.js';
  8. import ViewPosition from './position.js';
  9. import ViewRange from './range.js';
  10. import ViewSelection from './selection.js';
  11. import ViewDocumentFragment from './documentfragment.js';
  12. import { BR_FILLER, INLINE_FILLER_LENGTH, isBlockFiller, isInlineFiller, startsWithFiller, getDataWithoutFiller } from './filler.js';
  13. import indexOf from '../../utils/dom/indexof.js';
  14. /**
  15. * DomConverter is a set of tools to do transformations between DOM nodes and view nodes. It also handles
  16. * {@link engine.treeView.DomConverter#bindElements binding} these nodes.
  17. *
  18. * DomConverter does not check which nodes should be rendered (use {@link engine.treeView.Renderer}), does not keep a
  19. * state of a tree nor keeps synchronization between tree view and DOM tree (use {@link engine.treeView.Document}).
  20. *
  21. * DomConverter keeps DOM elements to View element bindings, so when the converter will be destroyed, the binding will
  22. * be lost. Two converters will keep separate binding maps, so one tree view can be bound with two DOM trees.
  23. *
  24. * @memberOf engine.treeView
  25. */
  26. export default class DomConverter {
  27. /**
  28. * Creates DOM converter.
  29. *
  30. * @param {Object} options Object with configuration options.
  31. * @param {Function} [options.blockFiller=engine.treeView.filler.BR_FILLER] Block filler creator.
  32. */
  33. constructor( options = {} ) {
  34. // Using WeakMap prevent memory leaks: when the converter will be destroyed all referenced between View and DOM
  35. // will be removed. Also because it is a *Weak*Map when both view and DOM elements will be removed referenced
  36. // will be also removed, isn't it brilliant?
  37. //
  38. // Yes, PJ. It is.
  39. //
  40. // You guys so smart.
  41. //
  42. // I've been here. Seen stuff. Afraid of code now.
  43. /**
  44. * Block {@link engine.treeView.filler filler} creator, which is used to create all block fillers during the
  45. * view to DOM conversion and to recognize block fillers during the DOM to view conversion.
  46. *
  47. * @readonly
  48. * @member {Function} engine.treeView.DomConverter#blockFiller
  49. */
  50. this.blockFiller = options.blockFiller || BR_FILLER;
  51. /**
  52. * DOM to View mapping.
  53. *
  54. * @private
  55. * @member {WeakMap} engine.treeView.DomConverter#_domToViewMapping
  56. */
  57. this._domToViewMapping = new WeakMap();
  58. /**
  59. * View to DOM mapping.
  60. *
  61. * @private
  62. * @member {WeakMap} engine.treeView.DomConverter#_viewToDomMapping
  63. */
  64. this._viewToDomMapping = new WeakMap();
  65. }
  66. /**
  67. * Binds DOM and View elements, so it will be possible to get corresponding elements using
  68. * {@link engine.treeView.DomConverter#getCorrespondingViewElement getCorrespondingViewElement} and
  69. * {@link engine.treeView.DomConverter#getCorrespondingDomElement getCorrespondingDomElement}.
  70. *
  71. * @param {HTMLElement} domElement DOM element to bind.
  72. * @param {engine.treeView.Element} viewElement View element to bind.
  73. */
  74. bindElements( domElement, viewElement ) {
  75. this._domToViewMapping.set( domElement, viewElement );
  76. this._viewToDomMapping.set( viewElement, domElement );
  77. }
  78. /**
  79. * Binds DOM and View document fragments, so it will be possible to get corresponding document fragments using
  80. * {@link engine.treeView.DomConverter#getCorrespondingViewDocumentFragment getCorrespondingViewDocumentFragment} and
  81. * {@link engine.treeView.DomConverter#getCorrespondingDomDocumentFragment getCorrespondingDomDocumentFragment}.
  82. *
  83. * @param {DocumentFragment} domFragment DOM document fragment to bind.
  84. * @param {engine.treeView.DocumentFragment} viewFragment View document fragment to bind.
  85. */
  86. bindDocumentFragments( domFragment, viewFragment ) {
  87. this._domToViewMapping.set( domFragment, viewFragment );
  88. this._viewToDomMapping.set( viewFragment, domFragment );
  89. }
  90. /**
  91. * Converts view to DOM. For all text nodes, not bound elements and document fragments new items will
  92. * be created. For bound elements and document fragments function will return corresponding items.
  93. *
  94. * @param {engine.treeView.Node|engine.treeView.DocumentFragment} viewNode View node or document fragment to transform.
  95. * @param {document} domDocument Document which will be used to create DOM nodes.
  96. * @param {Object} [options] Conversion options.
  97. * @param {Boolean} [options.bind=false] Determines whether new elements will be bound.
  98. * @param {Boolean} [options.withChildren=true] If true node's and document fragment's children will be converted too.
  99. * @returns {Node|DocumentFragment} Converted node or DocumentFragment.
  100. */
  101. viewToDom( viewNode, domDocument, options = {} ) {
  102. if ( viewNode instanceof ViewText ) {
  103. return domDocument.createTextNode( viewNode.data );
  104. } else {
  105. if ( this.getCorrespondingDom( viewNode ) ) {
  106. return this.getCorrespondingDom( viewNode );
  107. }
  108. let domElement;
  109. if ( viewNode instanceof ViewDocumentFragment ) {
  110. // Create DOM document fragment.
  111. domElement = domDocument.createDocumentFragment();
  112. if ( options.bind ) {
  113. this.bindDocumentFragments( domElement, viewNode );
  114. }
  115. } else {
  116. // Create DOM element.
  117. domElement = domDocument.createElement( viewNode.name );
  118. if ( options.bind ) {
  119. this.bindElements( domElement, viewNode );
  120. }
  121. // Copy element's attributes.
  122. for ( let key of viewNode.getAttributeKeys() ) {
  123. domElement.setAttribute( key, viewNode.getAttribute( key ) );
  124. }
  125. }
  126. if ( options.withChildren || options.withChildren === undefined ) {
  127. for ( let child of this.viewChildrenToDom( viewNode, domDocument, options ) ) {
  128. domElement.appendChild( child );
  129. }
  130. }
  131. return domElement;
  132. }
  133. }
  134. /**
  135. * Converts children of the view element to DOM using {@link engine.treeView.DomConverter#viewToDom} method.
  136. * Additionally this method adds block {@link engine.treeView.filler filler} to the list of children, if needed.
  137. *
  138. * @param {engine.treeView.Element|engine.treeView.DocumentFragment} viewElement Parent view element.
  139. * @param {document} domDocument Document which will be used to create DOM nodes.
  140. * @param {Object} options See {@link engine.treeView.DomConverter#viewToDom} options parameter.
  141. * @returns {Iterable.<Node>} DOM nodes.
  142. */
  143. *viewChildrenToDom( viewElement, domDocument, options = {} ) {
  144. let fillerPositionOffset = viewElement.getFillerOffset && viewElement.getFillerOffset();
  145. let offset = 0;
  146. for ( let childView of viewElement.getChildren() ) {
  147. if ( fillerPositionOffset === offset ) {
  148. yield this.blockFiller( domDocument );
  149. }
  150. yield this.viewToDom( childView, domDocument, options );
  151. offset++;
  152. }
  153. if ( fillerPositionOffset === offset ) {
  154. yield this.blockFiller( domDocument );
  155. }
  156. }
  157. /**
  158. * Converts view {@link engine.treeView.Range} to DOM range.
  159. * Inline and block {@link engine.treeView.filler fillers} are handled during the conversion.
  160. *
  161. * @param {engine.treeView.Range} viewRange View range.
  162. * @returns {Range} DOM range.
  163. */
  164. viewRangeToDom( viewRange ) {
  165. const domStart = this.viewPositionToDom( viewRange.start );
  166. const domEnd = this.viewPositionToDom( viewRange.end );
  167. const domRange = new Range();
  168. domRange.setStart( domStart.parent, domStart.offset );
  169. domRange.setEnd( domEnd.parent, domEnd.offset );
  170. return domRange;
  171. }
  172. /**
  173. * Converts view {@link engine.treeView.Position} to DOM parent and offset.
  174. *
  175. * Inline and block {@link engine.treeView.filler fillers} are handled during the conversion.
  176. * If the converted position is directly before inline filler it is moved inside the filler.
  177. *
  178. * @param {engine.treeView.position} viewPosition View position.
  179. * @returns {Object} position
  180. * @returns {Node} position.parent DOM position parent.
  181. * @returns {Number} position.offset DOM position offset.
  182. */
  183. viewPositionToDom( viewPosition ) {
  184. const viewParent = viewPosition.parent;
  185. if ( viewParent instanceof ViewText ) {
  186. const domParent = this.getCorrespondingDomText( viewParent );
  187. let offset = viewPosition.offset;
  188. if ( startsWithFiller( domParent ) ) {
  189. offset += INLINE_FILLER_LENGTH;
  190. }
  191. return { parent: domParent, offset: offset };
  192. }
  193. // viewParent instance of ViewElement.
  194. else {
  195. let domParent, domBefore, domAfter;
  196. if ( viewPosition.offset === 0 ) {
  197. domParent = this.getCorrespondingDom( viewPosition.parent );
  198. domAfter = domParent.childNodes[ 0 ];
  199. } else {
  200. domBefore = this.getCorrespondingDom( viewPosition.nodeBefore );
  201. domParent = domBefore.parentNode;
  202. domAfter = domBefore.nextSibling;
  203. }
  204. // If there is an inline filler at position return position inside the filler. We should never return
  205. // the position before the inline filler.
  206. if ( domAfter instanceof Text && startsWithFiller( domAfter ) ) {
  207. return { parent: domAfter, offset: INLINE_FILLER_LENGTH };
  208. }
  209. const offset = domBefore ? indexOf( domBefore ) + 1 : 0;
  210. return { parent: domParent, offset: offset };
  211. }
  212. }
  213. /**
  214. * Converts DOM to view. For all text nodes, not bound elements and document fragments new items will
  215. * be created. For bound elements and document fragments function will return corresponding items. For
  216. * {@link engine.treeView.filler fillers} `null` will be returned.
  217. *
  218. * @param {Node|DocumentFragment} domNode DOM node or document fragment to transform.
  219. * @param {Object} [options] Conversion options.
  220. * @param {Boolean} [options.bind=false] Determines whether new elements will be bound.
  221. * @param {Boolean} [options.withChildren=true] It true node's and document fragment's children will be converted too.
  222. * @returns {engine.treeView.Node|engine.treeView.DocumentFragment|null} Converted node or document fragment. Null
  223. * if DOM node is a {@link engine.treeView.filler filler}.
  224. */
  225. domToView( domNode, options = {} ) {
  226. if ( isBlockFiller( domNode, this.blockFiller ) ) {
  227. return null;
  228. }
  229. if ( domNode instanceof Text ) {
  230. if ( isInlineFiller( domNode ) ) {
  231. return null;
  232. } else {
  233. return new ViewText( getDataWithoutFiller( domNode ) );
  234. }
  235. } else {
  236. if ( this.getCorrespondingView( domNode ) ) {
  237. return this.getCorrespondingView( domNode );
  238. }
  239. let viewElement;
  240. if ( domNode instanceof DocumentFragment ) {
  241. // Create view document fragment.
  242. viewElement = new ViewDocumentFragment();
  243. if ( options.bind ) {
  244. this.bindDocumentFragments( domNode, viewElement );
  245. }
  246. } else {
  247. // Create view element.
  248. viewElement = new ViewElement( domNode.tagName.toLowerCase() );
  249. if ( options.bind ) {
  250. this.bindElements( domNode, viewElement );
  251. }
  252. // Copy element's attributes.
  253. const attrs = domNode.attributes;
  254. for ( let i = attrs.length - 1; i >= 0; i-- ) {
  255. viewElement.setAttribute( attrs[ i ].name, attrs[ i ].value );
  256. }
  257. }
  258. if ( options.withChildren || options.withChildren === undefined ) {
  259. for ( let child of this.domChildrenToView( domNode, options ) ) {
  260. viewElement.appendChildren( child );
  261. }
  262. }
  263. return viewElement;
  264. }
  265. }
  266. /**
  267. * Converts children of the DOM element to view nodes using {@link engine.treeView.DomConverter#domToView} method.
  268. * Additionally this method omits block {@link engine.treeView.filler filler}, if it exists in the DOM parent.
  269. *
  270. * @param {HTMLElement} domElement Parent DOM element.
  271. * @param {Object} options See {@link engine.treeView.DomConverter#domToView} options parameter.
  272. * @returns {Iterable.<engine.treeView.Node>} View nodes.
  273. */
  274. *domChildrenToView( domElement, options = {} ) {
  275. for ( let i = 0; i < domElement.childNodes.length; i++ ) {
  276. const domChild = domElement.childNodes[ i ];
  277. const viewChild = this.domToView( domChild, options );
  278. if ( viewChild !== null ) {
  279. yield viewChild;
  280. }
  281. }
  282. }
  283. /**
  284. * Converts DOM selection to view {@link engine.treeView.Selection}.
  285. * Ranges which cannot be converted will be omitted.
  286. *
  287. * @param {Selection} domSelection DOM selection.
  288. * @returns {engine.treeView.Selection} View selection.
  289. */
  290. domSelectionToView( domSelection ) {
  291. const viewSelection = new ViewSelection();
  292. for ( let i = 0; i < domSelection.rangeCount; i++ ) {
  293. const domRange = domSelection.getRangeAt( i );
  294. const viewRange = this.domRangeToView( domRange );
  295. if ( viewRange ) {
  296. viewSelection.addRange( viewRange );
  297. }
  298. }
  299. return viewSelection;
  300. }
  301. /**
  302. * Converts DOM Range to view {@link engine.treeView.range}.
  303. * If the start or end position can not be converted `null` is returned.
  304. *
  305. * @param {Range} domRange DOM range.
  306. * @returns {engine.treeView.Range|null} View range.
  307. */
  308. domRangeToView( domRange ) {
  309. const viewStart = this.domPositionToView( domRange.startContainer, domRange.startOffset );
  310. const viewEnd = this.domPositionToView( domRange.endContainer, domRange.endOffset );
  311. if ( viewStart && viewEnd ) {
  312. return new ViewRange( viewStart, viewEnd );
  313. }
  314. return null;
  315. }
  316. /**
  317. * Converts DOM parent and offset to view {@link engine.treeView.Position}.
  318. *
  319. * If the position is inside a {@link engine.treeView.filler filler} which has no corresponding view node,
  320. * position of the filler will be converted and returned.
  321. *
  322. * If structures are too different and it is not possible to find corresponding position then `null` will be returned.
  323. *
  324. * @param {Node} domParent DOM position parent.
  325. * @param {Number} domOffset DOM position offset.
  326. * @returns {engine.treeView.Position} viewPosition View position.
  327. */
  328. domPositionToView( domParent, domOffset ) {
  329. if ( isBlockFiller( domParent, this.blockFiller ) ) {
  330. return this.domPositionToView( domParent.parentNode, indexOf( domParent ) );
  331. }
  332. if ( domParent instanceof Text ) {
  333. if ( isInlineFiller( domParent ) ) {
  334. return this.domPositionToView( domParent.parentNode, indexOf( domParent ) );
  335. }
  336. const viewParent = this.getCorrespondingViewText( domParent );
  337. let offset = domOffset;
  338. if ( !viewParent ) {
  339. return null;
  340. }
  341. if ( startsWithFiller( domParent ) ) {
  342. offset -= INLINE_FILLER_LENGTH;
  343. offset = offset < 0 ? 0 : offset;
  344. }
  345. return new ViewPosition( viewParent, offset );
  346. }
  347. // domParent instanceof HTMLElement.
  348. else {
  349. if ( domOffset === 0 ) {
  350. const viewParent = this.getCorrespondingView( domParent );
  351. if ( viewParent ) {
  352. return new ViewPosition( viewParent, 0 );
  353. }
  354. } else {
  355. const viewBefore = this.getCorrespondingView( domParent.childNodes[ domOffset - 1 ] );
  356. if ( viewBefore ) {
  357. return new ViewPosition( viewBefore.parent, viewBefore.getIndex() + 1 );
  358. }
  359. }
  360. return null;
  361. }
  362. }
  363. /**
  364. * Gets corresponding view item. This function use
  365. * {@link engine.treeView.DomConverter#getCorrespondingViewElement getCorrespondingViewElement}
  366. * for elements, {@link engine.treeView.DomConverter#getCorrespondingViewText getCorrespondingViewText} for text
  367. * nodes and {@link engine.treeView.DomConverter#getCorrespondingViewDocumentFragment getCorrespondingViewDocumentFragment}
  368. * for document fragments.
  369. *
  370. * Note that for the block or inline {@link engine.treeView.filler filler} this method returns `null`.
  371. *
  372. * @param {Node|DocumentFragment} domNode DOM node or document fragment.
  373. * @returns {engine.treeView.Node|engine.treeView.DocumentFragment|null} Corresponding view item.
  374. */
  375. getCorrespondingView( domNode ) {
  376. if ( domNode instanceof HTMLElement ) {
  377. return this.getCorrespondingViewElement( domNode );
  378. } else if ( domNode instanceof DocumentFragment ) {
  379. return this.getCorrespondingViewDocumentFragment( domNode );
  380. } else if ( domNode instanceof Text ) {
  381. return this.getCorrespondingViewText( domNode );
  382. }
  383. return null;
  384. }
  385. /**
  386. * Gets corresponding view element. Returns element if an view element was
  387. * {@link engine.treeView.DomConverter#bindElements bound} to the given DOM element or `null` otherwise.
  388. *
  389. * @param {HTMLElement} domElement DOM element.
  390. * @returns {engine.treeView.Element|null} Corresponding element or `null` if no element was bound.
  391. */
  392. getCorrespondingViewElement( domElement ) {
  393. return this._domToViewMapping.get( domElement );
  394. }
  395. /**
  396. * Gets corresponding view document fragment. Returns document fragment if an view element was
  397. * {@link engine.treeView.DomConverter#bindDocumentFragments bound} to the given DOM fragment or `null` otherwise.
  398. *
  399. * @param {DocumentFragment} domFragment DOM element.
  400. * @returns {engine.treeView.DocumentFragment|null} Corresponding document fragment or `null` if none element was bound.
  401. */
  402. getCorrespondingViewDocumentFragment( domFragment ) {
  403. return this._domToViewMapping.get( domFragment );
  404. }
  405. /**
  406. * Gets corresponding text node. Text nodes are not {@link engine.treeView.DomConverter#bindElements bound},
  407. * corresponding text node is returned based on the sibling or parent.
  408. *
  409. * If the directly previous sibling is a {@link engine.treeView.DomConverter#bindElements bound} element, it is used
  410. * to find the corresponding text node.
  411. *
  412. * If this is a first child in the parent and the parent is a {@link engine.treeView.DomConverter#bindElements bound}
  413. * element, it is used to find the corresponding text node.
  414. *
  415. * Otherwise `null` is returned.
  416. *
  417. * Note that for the block or inline {@link engine.treeView.filler filler} this method returns `null`.
  418. *
  419. * @param {Text} domText DOM text node.
  420. * @returns {engine.treeView.Text|null} Corresponding view text node or `null`, if it was not possible to find a
  421. * corresponding node.
  422. */
  423. getCorrespondingViewText( domText ) {
  424. if ( isInlineFiller( domText ) ) {
  425. return null;
  426. }
  427. const previousSibling = domText.previousSibling;
  428. // Try to use previous sibling to find the corresponding text node.
  429. if ( previousSibling ) {
  430. if ( !( previousSibling instanceof HTMLElement ) ) {
  431. // The previous is text or comment.
  432. return null;
  433. }
  434. const viewElement = this.getCorrespondingViewElement( previousSibling );
  435. if ( viewElement ) {
  436. const nextSibling = viewElement.getNextSibling();
  437. // It might be filler which has no corresponding view node.
  438. if ( nextSibling instanceof ViewText ) {
  439. return viewElement.getNextSibling();
  440. } else {
  441. return null;
  442. }
  443. }
  444. }
  445. // Try to use parent to find the corresponding text node.
  446. else {
  447. const viewElement = this.getCorrespondingViewElement( domText.parentNode );
  448. if ( viewElement ) {
  449. const firstChild = viewElement.getChild( 0 );
  450. // It might be filler which has no corresponding view node.
  451. if ( firstChild instanceof ViewText ) {
  452. return firstChild;
  453. } else {
  454. return null;
  455. }
  456. }
  457. }
  458. return null;
  459. }
  460. /**
  461. * Gets corresponding DOM item. This function uses
  462. * {@link engine.treeView.DomConverter#getCorrespondingDomElement getCorrespondingDomElement} for
  463. * elements, {@link engine.treeView.DomConverter#getCorrespondingDomText getCorrespondingDomText} for text nodes
  464. * and {@link engine.treeView.DomConverter#getCorrespondingDomDocumentFragment getCorrespondingDomDocumentFragment}
  465. * for document fragments.
  466. *
  467. * @param {engine.treeView.Node|engine.treeView.DomFragment} viewNode View node or document fragment.
  468. * @returns {Node|DocumentFragment|null} Corresponding DOM node or document fragment.
  469. */
  470. getCorrespondingDom( viewNode ) {
  471. if ( viewNode instanceof ViewElement ) {
  472. return this.getCorrespondingDomElement( viewNode );
  473. } else if ( viewNode instanceof ViewDocumentFragment ) {
  474. return this.getCorrespondingDomDocumentFragment( viewNode );
  475. } else {
  476. return this.getCorrespondingDomText( viewNode );
  477. }
  478. }
  479. /**
  480. * Gets corresponding DOM element. Returns element if an DOM element was
  481. * {@link engine.treeView.DomConverter#bindElements bound} to the given view element or `null` otherwise.
  482. *
  483. * @param {engine.treeView.Element} viewElement View element.
  484. * @returns {HTMLElement|null} Corresponding element or `null` if none element was bound.
  485. */
  486. getCorrespondingDomElement( viewElement ) {
  487. return this._viewToDomMapping.get( viewElement );
  488. }
  489. /**
  490. * Gets corresponding DOM document fragment. Returns document fragment if an DOM element was
  491. * {@link engine.treeView.DomConverter#bindDocumentFragments bound} to the given view document fragment or `null` otherwise.
  492. *
  493. * @param {engine.treeView.DocumentFragment} viewDocumentFragment View document fragment.
  494. * @returns {DocumentFragment|null} Corresponding document fragment or `null` if no fragment was bound.
  495. */
  496. getCorrespondingDomDocumentFragment( viewDocumentFragment ) {
  497. return this._viewToDomMapping.get( viewDocumentFragment );
  498. }
  499. /**
  500. * Gets corresponding text node. Text nodes are not {@link engine.treeView.DomConverter#bindElements bound},
  501. * corresponding text node is returned based on the sibling or parent.
  502. *
  503. * If the directly previous sibling is a {@link engine.treeView.DomConverter#bindElements bound} element, it is used
  504. * to find the corresponding text node.
  505. *
  506. * If this is a first child in the parent and the parent is a {@link engine.treeView.DomConverter#bindElements bound}
  507. * element, it is used to find the corresponding text node.
  508. *
  509. * Otherwise `null` is returned.
  510. *
  511. * @param {engine.treeView.Text} viewText View text node.
  512. * @returns {Text|null} Corresponding DOM text node or `null`, if it was not possible to find a corresponding node.
  513. */
  514. getCorrespondingDomText( viewText ) {
  515. const previousSibling = viewText.getPreviousSibling();
  516. // Try to use previous sibling to find the corresponding text node.
  517. if ( previousSibling && this.getCorrespondingDom( previousSibling ) ) {
  518. return this.getCorrespondingDom( previousSibling ).nextSibling;
  519. }
  520. // Try to use parent to find the corresponding text node.
  521. if ( !previousSibling && this.getCorrespondingDom( viewText.parent ) ) {
  522. return this.getCorrespondingDom( viewText.parent ).childNodes[ 0 ];
  523. }
  524. return null;
  525. }
  526. }