/**
* @license
* Copyright The Closure Library Authors.
* SPDX-License-Identifier: Apache-2.0
*/
/**
* @fileoverview Utilities for working with ranges in HTML documents.
*
* @suppress {strictMissingProperties}
*/
goog.provide('goog.dom.Range');
goog.require('goog.dom');
goog.require('goog.dom.AbstractRange');
goog.require('goog.dom.ControlRange');
goog.require('goog.dom.MultiRange');
goog.require('goog.dom.NodeType');
goog.require('goog.dom.TextRange');
/**
* Create a new selection from the given browser window's current selection.
* Note that this object does not auto-update if the user changes their
* selection and should be used as a snapshot.
* @param {Window=} opt_win The window to get the selection of. Defaults to the
* window this class was defined in.
* @return {goog.dom.AbstractRange?} A range wrapper object, or null if there
* was an error.
*/
goog.dom.Range.createFromWindow = function(opt_win) {
'use strict';
var sel =
goog.dom.AbstractRange.getBrowserSelectionForWindow(opt_win || window);
return sel && goog.dom.Range.createFromBrowserSelection(sel);
};
/**
* Create a new range wrapper from the given browser selection object. Note
* that this object does not auto-update if the user changes their selection and
* should be used as a snapshot.
* @param {!Object} selection The browser selection object.
* @return {goog.dom.AbstractRange?} A range wrapper object or null if there
* was an error.
*/
goog.dom.Range.createFromBrowserSelection = function(selection) {
'use strict';
var range;
var isReversed = false;
if (selection.createRange) {
try {
range = selection.createRange();
} catch (e) {
// Access denied errors can be thrown here in IE if the selection was
// a flash obj or if there are cross domain issues
return null;
}
} else if (selection.rangeCount) {
if (selection.rangeCount > 1) {
return goog.dom.MultiRange.createFromBrowserSelection(
/** @type {!Selection} */ (selection));
} else {
range = selection.getRangeAt(0);
isReversed = goog.dom.Range.isReversed(
selection.anchorNode, selection.anchorOffset, selection.focusNode,
selection.focusOffset);
}
} else {
return null;
}
return goog.dom.Range.createFromBrowserRange(range, isReversed);
};
/**
* Create a new range wrapper from the given browser range object.
* @param {Range|TextRange} range The browser range object.
* @param {boolean=} opt_isReversed Whether the focus node is before the anchor
* node.
* @return {!goog.dom.AbstractRange} A range wrapper object.
*/
goog.dom.Range.createFromBrowserRange = function(range, opt_isReversed) {
'use strict';
// Create an IE control range when appropriate.
return goog.dom.AbstractRange.isNativeControlRange(range) ?
goog.dom.ControlRange.createFromBrowserRange(range) :
goog.dom.TextRange.createFromBrowserRange(range, opt_isReversed);
};
/**
* Create a new range wrapper that selects the given node's text.
* @param {Node} node The node to select.
* @param {boolean=} opt_isReversed Whether the focus node is before the anchor
* node.
* @return {!goog.dom.AbstractRange} A range wrapper object.
*/
goog.dom.Range.createFromNodeContents = function(node, opt_isReversed) {
'use strict';
return goog.dom.TextRange.createFromNodeContents(node, opt_isReversed);
};
/**
* Create a new range wrapper that represents a caret at the given node,
* accounting for the given offset. This always creates a TextRange, regardless
* of whether node is an image node or other control range type node.
* @param {Node} node The node to place a caret at.
* @param {number} offset The offset within the node to place the caret at.
* @return {!goog.dom.AbstractRange} A range wrapper object.
*/
goog.dom.Range.createCaret = function(node, offset) {
'use strict';
return goog.dom.TextRange.createFromNodes(node, offset, node, offset);
};
/**
* Create a new range wrapper that selects the area between the given nodes,
* accounting for the given offsets.
* @param {Node} anchorNode The node to anchor on.
* @param {number} anchorOffset The offset within the node to anchor on.
* @param {Node} focusNode The node to focus on.
* @param {number} focusOffset The offset within the node to focus on.
* @return {!goog.dom.AbstractRange} A range wrapper object.
*/
goog.dom.Range.createFromNodes = function(
anchorNode, anchorOffset, focusNode, focusOffset) {
'use strict';
return goog.dom.TextRange.createFromNodes(
anchorNode, anchorOffset, focusNode, focusOffset);
};
/**
* Clears the window's selection.
* @param {Window=} opt_win The window to get the selection of. Defaults to the
* window this class was defined in.
*/
goog.dom.Range.clearSelection = function(opt_win) {
'use strict';
var sel =
goog.dom.AbstractRange.getBrowserSelectionForWindow(opt_win || window);
if (!sel) {
return;
}
if (sel.empty) {
// We can't just check that the selection is empty, because IE
// sometimes gets confused.
try {
sel.empty();
} catch (e) {
// Emptying an already empty selection throws an exception in IE
}
} else {
try {
sel.removeAllRanges();
} catch (e) {
// This throws in IE9 if the range has been invalidated; for example, if
// the user clicked on an element which disappeared during the event
// handler.
}
}
};
/**
* Tests if the window has a selection.
* @param {Window=} opt_win The window to check the selection of. Defaults to
* the window this class was defined in.
* @return {boolean} Whether the window has a selection.
*/
goog.dom.Range.hasSelection = function(opt_win) {
'use strict';
var sel =
goog.dom.AbstractRange.getBrowserSelectionForWindow(opt_win || window);
return !!(sel && sel.rangeCount);
};
/**
* Returns whether the focus position occurs before the anchor position.
* @param {Node} anchorNode The node to anchor on.
* @param {number} anchorOffset The offset within the node to anchor on.
* @param {Node} focusNode The node to focus on.
* @param {number} focusOffset The offset within the node to focus on.
* @return {boolean} Whether the focus position occurs before the anchor
* position.
*/
goog.dom.Range.isReversed = function(
anchorNode, anchorOffset, focusNode, focusOffset) {
'use strict';
if (anchorNode == focusNode) {
return focusOffset < anchorOffset;
}
var child;
if (anchorNode.nodeType == goog.dom.NodeType.ELEMENT && anchorOffset) {
child = anchorNode.childNodes[anchorOffset];
if (child) {
anchorNode = child;
anchorOffset = 0;
} else if (goog.dom.contains(anchorNode, focusNode)) {
// If focus node is contained in anchorNode, it must be before the
// end of the node. Hence we are reversed.
return true;
}
}
if (focusNode.nodeType == goog.dom.NodeType.ELEMENT && focusOffset) {
child = focusNode.childNodes[focusOffset];
if (child) {
focusNode = child;
focusOffset = 0;
} else if (goog.dom.contains(focusNode, anchorNode)) {
// If anchor node is contained in focusNode, it must be before the
// end of the node. Hence we are not reversed.
return false;
}
}
return (goog.dom.compareNodeOrder(anchorNode, focusNode) ||
anchorOffset - focusOffset) > 0;
};