/**
 * @license Copyright (c) 2003-2018, CKSource - Frederico Knabben. All rights reserved.
 * For licensing, see LICENSE.md or https://ckeditor.com/legal/ckeditor-oss-license
 */

( function() {
	/**
	 * Represents a list os CKEDITOR.dom.range objects, which can be easily
	 * iterated sequentially.
	 *
	 * @class
	 * @extends Array
	 * @constructor Creates a rangeList class instance.
	 * @param {CKEDITOR.dom.range/CKEDITOR.dom.range[]} [ranges] The ranges contained on this list.
	 * Note that, if an array of ranges is specified, the range sequence
	 * should match its DOM order. This class will not help to sort them.
	 */
	CKEDITOR.dom.rangeList = function( ranges ) {
		if ( ranges instanceof CKEDITOR.dom.rangeList )
			return ranges;

		if ( !ranges )
			ranges = [];
		else if ( ranges instanceof CKEDITOR.dom.range )
			ranges = [ ranges ];

		return CKEDITOR.tools.extend( ranges, mixins );
	};

	var mixins = {
		/**
		 * Creates an instance of the rangeList iterator, it should be used
		 * only when the ranges processing could be DOM intrusive, which
		 * means it may pollute and break other ranges in this list.
		 * Otherwise, it's enough to just iterate over this array in a for loop.
		 *
		 * @returns {CKEDITOR.dom.rangeListIterator}
		 */
		createIterator: function() {
			var rangeList = this,
				bookmark = CKEDITOR.dom.walker.bookmark(),
				bookmarks = [],
				current;

			return {
				/**
				 * Retrieves the next range in the list.
				 *
				 * @member CKEDITOR.dom.rangeListIterator
				 * @param {Boolean} [mergeConsequent=false] Whether join two adjacent
				 * ranges into single, e.g. consequent table cells.
				 */
				getNextRange: function( mergeConsequent ) {
					current = current === undefined ? 0 : current + 1;

					var range = rangeList[ current ];

					// Multiple ranges might be mangled by each other.
					if ( range && rangeList.length > 1 ) {
						// Bookmarking all other ranges on the first iteration,
						// the range correctness after it doesn't matter since we'll
						// restore them before the next iteration.
						if ( !current ) {
							// Make sure bookmark correctness by reverse processing.
							for ( var i = rangeList.length - 1; i >= 0; i-- )
								bookmarks.unshift( rangeList[ i ].createBookmark( true ) );
						}

						if ( mergeConsequent ) {
							// Figure out how many ranges should be merged.
							var mergeCount = 0;
							while ( rangeList[ current + mergeCount + 1 ] ) {
								var doc = range.document,
									found = 0,
									left = doc.getById( bookmarks[ mergeCount ].endNode ),
									right = doc.getById( bookmarks[ mergeCount + 1 ].startNode ),
									next;

								// Check subsequent range.
								while ( 1 ) {
									next = left.getNextSourceNode( false );
									if ( !right.equals( next ) ) {
										// This could be yet another bookmark or
										// walking across block boundaries.
										if ( bookmark( next ) || ( next.type == CKEDITOR.NODE_ELEMENT && next.isBlockBoundary() ) ) {
											left = next;
											continue;
										}
									} else {
										found = 1;
									}

									break;
								}

								if ( !found )
									break;

								mergeCount++;
							}
						}

						range.moveToBookmark( bookmarks.shift() );

						// Merge ranges finally after moving to bookmarks.
						while ( mergeCount-- ) {
							next = rangeList[ ++current ];
							next.moveToBookmark( bookmarks.shift() );
							range.setEnd( next.endContainer, next.endOffset );
						}
					}

					return range;
				}
			};
		},

		/**
		 * Create bookmarks for all ranges. See {@link CKEDITOR.dom.range#createBookmark}.
		 *
		 * @param {Boolean} [serializable=false] See {@link CKEDITOR.dom.range#createBookmark}.
		 * @returns {Array} Array of bookmarks.
		 */
		createBookmarks: function( serializable ) {
			var retval = [],
				bookmark;
			for ( var i = 0; i < this.length; i++ ) {
				retval.push( bookmark = this[ i ].createBookmark( serializable, true ) );

				// Updating the container & offset values for ranges
				// that have been touched.
				for ( var j = i + 1; j < this.length; j++ ) {
					this[ j ] = updateDirtyRange( bookmark, this[ j ] );
					this[ j ] = updateDirtyRange( bookmark, this[ j ], true );
				}
			}
			return retval;
		},

		/**
		 * Create "unobtrusive" bookmarks for all ranges. See {@link CKEDITOR.dom.range#createBookmark2}.
		 *
		 * @param {Boolean} [normalized=false] See {@link CKEDITOR.dom.range#createBookmark2}.
		 * @returns {Array} Array of bookmarks.
		 */
		createBookmarks2: function( normalized ) {
			var bookmarks = [];

			for ( var i = 0; i < this.length; i++ )
				bookmarks.push( this[ i ].createBookmark2( normalized ) );

			return bookmarks;
		},

		/**
		 * Move each range in the list to the position specified by a list of bookmarks.
		 *
		 * @param {Array} bookmarks The list of bookmarks, each one matching a range in the list.
		 */
		moveToBookmarks: function( bookmarks ) {
			for ( var i = 0; i < this.length; i++ )
				this[ i ].moveToBookmark( bookmarks[ i ] );
		}
	};

	// Update the specified range which has been mangled by previous insertion of
	// range bookmark nodes.(https://dev.ckeditor.com/ticket/3256)
	function updateDirtyRange( bookmark, dirtyRange, checkEnd ) {
		var serializable = bookmark.serializable,
			container = dirtyRange[ checkEnd ? 'endContainer' : 'startContainer' ],
			offset = checkEnd ? 'endOffset' : 'startOffset';

		var bookmarkStart = serializable ? dirtyRange.document.getById( bookmark.startNode ) : bookmark.startNode;

		var bookmarkEnd = serializable ? dirtyRange.document.getById( bookmark.endNode ) : bookmark.endNode;

		if ( container.equals( bookmarkStart.getPrevious() ) ) {
			dirtyRange.startOffset = dirtyRange.startOffset - container.getLength() - bookmarkEnd.getPrevious().getLength();
			container = bookmarkEnd.getNext();
		} else if ( container.equals( bookmarkEnd.getPrevious() ) ) {
			dirtyRange.startOffset = dirtyRange.startOffset - container.getLength();
			container = bookmarkEnd.getNext();
		}

		container.equals( bookmarkStart.getParent() ) && dirtyRange[ offset ]++;
		container.equals( bookmarkEnd.getParent() ) && dirtyRange[ offset ]++;

		// Update and return this range.
		dirtyRange[ checkEnd ? 'endContainer' : 'startContainer' ] = container;
		return dirtyRange;
	}
} )();

/**
 * (Virtual Class) Do not call this constructor. This class is not really part
 * of the API. It just describes the return type of {@link CKEDITOR.dom.rangeList#createIterator}.
 *
 * @class CKEDITOR.dom.rangeListIterator
 */
