// Licensed under the Apache License, Version 2.0 (the "License");
// you may not use this file except in compliance with the License.
// You may obtain a copy of the License at
//
// http://www.apache.org/licenses/LICENSE-2.0
//
// Unless required by applicable law or agreed to in writing, software
// distributed under the License is distributed on an "AS IS" BASIS,
// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
// See the License for the specific language governing permissions and
// limitations under the License.
// Copyright 2007 Google Inc. All Rights Reserved.
/**
* @fileoverview Iterator between two DOM text range positions.
*
*/
goog.provide('goog.dom.TextRangeIterator');
goog.require('goog.array');
goog.require('goog.dom.NodeType');
goog.require('goog.dom.RangeIterator');
goog.require('goog.dom.TagName');
goog.require('goog.iter.StopIteration');
/**
* Subclass of goog.dom.TagIterator that iterates over a DOM range. It
* adds functions to determine the portion of each text node that is selected.
*
* @param {Node} startNode The starting node position.
* @param {number} startOffset The offset in to startNode. If startNode is
* an element, indicates an offset in to childNodes. If startNode is a
* text node, indicates an offset in to nodeValue.
* @param {Node} endNode The ending node position.
* @param {number} endOffset The offset in to endNode. If endNode is
* an element, indicates an offset in to childNodes. If endNode is a
* text node, indicates an offset in to nodeValue.
* @param {boolean} opt_reverse Whether to traverse nodes in reverse.
* @constructor
* @extends {goog.dom.RangeIterator}
*/
goog.dom.TextRangeIterator = function(startNode, startOffset, endNode,
endOffset, opt_reverse) {
var goNext;
if (startNode) {
this.startNode_ = startNode;
this.startOffset_ = startOffset;
this.endNode_ = endNode;
this.endOffset_ = endOffset;
// Skip to the offset nodes - being careful to special case BRs since these
// have no children but still can appear as the startContainer of a range.
if (startNode.nodeType == goog.dom.NodeType.ELEMENT &&
startNode.tagName != goog.dom.TagName.BR) {
var startChildren = startNode.childNodes;
var candidate = startChildren[startOffset];
if (candidate) {
this.startNode_ = candidate;
this.startOffset_ = 0;
} else {
if (startChildren.length) {
this.startNode_ =
/** @type {Node} */ (goog.array.peek(startChildren));
}
goNext = true;
}
}
if (endNode.nodeType == goog.dom.NodeType.ELEMENT) {
this.endNode_ = endNode.childNodes[endOffset];
if (this.endNode_) {
this.endOffset_ = 0;
} else {
// The offset was past the last element.
this.endNode_ = endNode;
}
}
}
goog.dom.RangeIterator.call(this, opt_reverse ? this.endNode_ :
this.startNode_, opt_reverse);
if (goNext) {
try {
this.next()
} catch (e) {
if (e != goog.iter.StopIteration) {
throw e;
}
}
}
};
goog.inherits(goog.dom.TextRangeIterator, goog.dom.RangeIterator);
/**
* The first node in the selection.
* @type {Node?}
* @private
*/
goog.dom.TextRangeIterator.prototype.startNode_ = null;
/**
* The last node in the selection.
* @type {Node?}
* @private
*/
goog.dom.TextRangeIterator.prototype.endNode_ = null;
/**
* The offset within the first node in the selection.
* @type {number}
* @private
*/
goog.dom.TextRangeIterator.prototype.startOffset_ = 0;
/**
* The offset within the last node in the selection.
* @type {number}
* @private
*/
goog.dom.TextRangeIterator.prototype.endOffset_ = 0;
/** @inheritDoc */
goog.dom.TextRangeIterator.prototype.getStartTextOffset = function() {
// Offsets only apply to text nodes. If our current node is the start node,
// return the saved offset. Otherwise, return 0.
return this.node.nodeType != goog.dom.NodeType.TEXT ? -1 :
this.node == this.startNode_ ? this.startOffset_ : 0;
};
/** @inheritDoc */
goog.dom.TextRangeIterator.prototype.getEndTextOffset = function() {
// Offsets only apply to text nodes. If our current node is the end node,
// return the saved offset. Otherwise, return the length of the node.
return this.node.nodeType != goog.dom.NodeType.TEXT ? -1 :
this.node == this.endNode_ ? this.endOffset_ : this.node.nodeValue.length;
};
/** @inheritDoc */
goog.dom.TextRangeIterator.prototype.getStartNode = function() {
return this.startNode_;
};
/**
* Change the start node of the iterator.
* @param {Node} node The new start node.
*/
goog.dom.TextRangeIterator.prototype.setStartNode = function(node) {
if (!this.isStarted()) {
this.setPosition(node);
}
this.startNode_ = node;
this.startOffset_ = 0;
};
/** @inheritDoc */
goog.dom.TextRangeIterator.prototype.getEndNode = function() {
return this.endNode_;
};
/**
* Change the end node of the iterator.
* @param {Node} node The new end node.
*/
goog.dom.TextRangeIterator.prototype.setEndNode = function(node) {
this.endNode_ = node;
this.endOffset_ = 0;
};
/** @inheritDoc */
goog.dom.TextRangeIterator.prototype.isLast = function() {
return this.isStarted() && this.node == this.endNode_ &&
(!this.endOffset_ || !this.isStartTag());
};
/**
* Move to the next position in the selection.
* Throws {@code goog.iter.StopIteration} when it passes the end of the range.
* @return {Node} The node at the next position.
*/
goog.dom.TextRangeIterator.prototype.next = function() {
if (this.isLast()) {
throw goog.iter.StopIteration;
}
// Call the super function.
return goog.dom.TextRangeIterator.superClass_.next.call(this);
};
/**
* Replace this iterator's values with values from another.
* @param {goog.dom.TextRangeIterator} other The iterator to copy.
* @protected
*/
goog.dom.TextRangeIterator.prototype.copyFrom = function(other) {
this.startNode_ = other.startNode_;
this.endNode_ = other.endNode_;
this.startOffset_ = other.startOffset_;
this.endOffset_ = other.endOffset_;
this.isReversed_ = other.isReversed_;
goog.dom.TextRangeIterator.superClass_.copyFrom.call(this, other);
};
/**
* @return {goog.dom.TextRangeIterator} An identical iterator.
*/
goog.dom.TextRangeIterator.prototype.clone = function() {
var copy = new goog.dom.TextRangeIterator(this.startNode_,
this.startOffset_, this.endNode_, this.endOffset_, this.isReversed_);
copy.copyFrom(this);
return copy;
};