/** * @license Copyright (c) 2003-2018, CKSource - Frederico Knabben. All rights reserved. * For licensing, see LICENSE.md. */ /** * Contains {@link module:engine/model/selection~Selection model selection} to * {@link module:engine/view/documentselection~DocumentSelection view selection} converters for * {@link module:engine/conversion/downcastdispatcher~DowncastDispatcher downcast dispatcher}. * * @module engine/conversion/downcast-selection-converters */ /** * Function factory that creates a converter which converts a non-collapsed {@link module:engine/model/selection~Selection model selection} * to a {@link module:engine/view/documentselection~DocumentSelection view selection}. The converter consumes appropriate * value from the `consumable` object and maps model positions from the selection to view positions. * * modelDispatcher.on( 'selection', convertRangeSelection() ); * * @returns {Function} Selection converter. */ export function convertRangeSelection() { return ( evt, data, conversionApi ) => { const selection = data.selection; if ( selection.isCollapsed ) { return; } if ( !conversionApi.consumable.consume( selection, 'selection' ) ) { return; } const viewRanges = []; for ( const range of selection.getRanges() ) { const viewRange = conversionApi.mapper.toViewRange( range ); viewRanges.push( viewRange ); } conversionApi.writer.setSelection( viewRanges, { backward: selection.isBackward } ); }; } /** * Function factory that creates a converter which converts a collapsed {@link module:engine/model/selection~Selection model selection} to * a {@link module:engine/view/documentselection~DocumentSelection view selection}. The converter consumes appropriate * value from the `consumable` object, maps the model selection position to the view position and breaks * {@link module:engine/view/attributeelement~AttributeElement attribute elements} at the selection position. * * modelDispatcher.on( 'selection', convertCollapsedSelection() ); * * An example of the view state before and after converting the collapsed selection: * *
f^oobar
* ->f^oobar
* * By breaking attribute elements like ``, the selection is in a correct element. Then, when the selection attribute is * converted, broken attributes might be merged again, or the position where the selection is may be wrapped * with different, appropriate attribute elements. * * See also {@link module:engine/conversion/downcast-selection-converters~clearAttributes} which does a clean-up * by merging attributes. * * @returns {Function} Selection converter. */ export function convertCollapsedSelection() { return ( evt, data, conversionApi ) => { const selection = data.selection; if ( !selection.isCollapsed ) { return; } if ( !conversionApi.consumable.consume( selection, 'selection' ) ) { return; } const viewWriter = conversionApi.writer; const modelPosition = selection.getFirstPosition(); const viewPosition = conversionApi.mapper.toViewPosition( modelPosition ); const brokenPosition = viewWriter.breakAttributes( viewPosition ); viewWriter.setSelection( brokenPosition ); }; } /** * Function factory that creates a converter which clears artifacts after the previous * {@link module:engine/model/selection~Selection model selection} conversion. It removes all empty * {@link module:engine/view/attributeelement~AttributeElement view attribute elements} and merges sibling attributes at all start and end * positions of all ranges. * *^
* ->^
* *foo^barbar
* ->foo^barbar
* *foo^barbar
* ->foo^barbar
* * This listener should be assigned before any converter for the new selection: * * modelDispatcher.on( 'selection', clearAttributes() ); * * See {@link module:engine/conversion/downcast-selection-converters~convertCollapsedSelection} * which does the opposite by breaking attributes in the selection position. * * @returns {Function} Selection converter. */ export function clearAttributes() { return ( evt, data, conversionApi ) => { const viewWriter = conversionApi.writer; const viewSelection = viewWriter.document.selection; for ( const range of viewSelection.getRanges() ) { // Not collapsed selection should not have artifacts. if ( range.isCollapsed ) { // Position might be in the node removed by the view writer. if ( range.end.parent.document ) { conversionApi.writer.mergeAttributes( range.start ); } } } viewWriter.setSelection( null ); }; }