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