/* -*- Mode: C++; tab-width: 8; indent-tabs-mode: nil; c-basic-offset: 2 -*- */ /* vim: set ft=javascript ts=2 et sw=2 tw=80: */ /* ***** BEGIN LICENSE BLOCK ***** * Version: MPL 1.1/GPL 2.0/LGPL 2.1 * * The contents of this file are subject to the Mozilla Public License Version * 1.1 (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.mozilla.org/MPL/ * * Software distributed under the License is distributed on an "AS IS" basis, * WITHOUT WARRANTY OF ANY KIND, either express or implied. See the License * for the specific language governing rights and limitations under the * License. * * The Original Code is the Mozilla LayoutHelpers Module. * * The Initial Developer of the Original Code is * The Mozilla Foundation. * Portions created by the Initial Developer are Copyright (C) 2010 * the Initial Developer. All Rights Reserved. * * Contributor(s): * Rob Campbell (original author) * Mihai Șucan * Julian Viereck * Paul Rouget * Kyle Simpson * * Alternatively, the contents of this file may be used under the terms of * either the GNU General Public License Version 2 or later (the "GPL"), or * the GNU Lesser General Public License Version 2.1 or later (the "LGPL"), * in which case the provisions of the GPL or the LGPL are applicable instead * of those above. If you wish to allow use of your version of this file only * under the terms of either the GPL or the LGPL, and not to allow others to * use your version of this file under the terms of the MPL, indicate your * decision by deleting the provisions above and replace them with the notice * and other provisions required by the GPL or the LGPL. If you do not delete * the provisions above, a recipient may use your version of this file under * the terms of any one of the MPL, the GPL or the LGPL. * * ***** END LICENSE BLOCK ***** */ const Cu = Components.utils; const Ci = Components.interfaces; const Cr = Components.results; var EXPORTED_SYMBOLS = ["LayoutHelpers"]; LayoutHelpers = { /** * Compute the position and the dimensions for the visible portion * of a node, relativalely to the root window. * * @param nsIDOMNode aNode * a DOM element to be highlighted */ getDirtyRect: function LH_getDirectyRect(aNode) { let frameWin = aNode.ownerDocument.defaultView; let clientRect = aNode.getBoundingClientRect(); // Go up in the tree of frames to determine the correct rectangle. // clientRect is read-only, we need to be able to change properties. rect = {top: clientRect.top, left: clientRect.left, width: clientRect.width, height: clientRect.height}; // We iterate through all the parent windows. while (true) { // Does the selection overflow on the right of its window? let diffx = frameWin.innerWidth - (rect.left + rect.width); if (diffx < 0) { rect.width += diffx; } // Does the selection overflow on the bottom of its window? let diffy = frameWin.innerHeight - (rect.top + rect.height); if (diffy < 0) { rect.height += diffy; } // Does the selection overflow on the left of its window? if (rect.left < 0) { rect.width += rect.left; rect.left = 0; } // Does the selection overflow on the top of its window? if (rect.top < 0) { rect.height += rect.top; rect.top = 0; } // Selection has been clipped to fit in its own window. // Are we in the top-level window? if (frameWin.parent === frameWin || !frameWin.frameElement) { break; } // We are in an iframe. // We take into account the parent iframe position and its // offset (borders and padding). let frameRect = frameWin.frameElement.getBoundingClientRect(); let [offsetTop, offsetLeft] = this.getIframeContentOffset(frameWin.frameElement); rect.top += frameRect.top + offsetTop; rect.left += frameRect.left + offsetLeft; frameWin = frameWin.parent; } return rect; }, /** * Compute the absolute position and the dimensions of a node, relativalely * to the root window. * * @param nsIDOMNode aNode * a DOM element to get the bounds for * @param nsIWindow aContentWindow * the content window holding the node */ getRect: function LH_getRect(aNode, aContentWindow) { let frameWin = aNode.ownerDocument.defaultView; let clientRect = aNode.getBoundingClientRect(); // Go up in the tree of frames to determine the correct rectangle. // clientRect is read-only, we need to be able to change properties. rect = {top: clientRect.top + aContentWindow.pageYOffset, left: clientRect.left + aContentWindow.pageXOffset, width: clientRect.width, height: clientRect.height}; // We iterate through all the parent windows. while (true) { // Are we in the top-level window? if (frameWin.parent === frameWin || !frameWin.frameElement) { break; } // We are in an iframe. // We take into account the parent iframe position and its // offset (borders and padding). let frameRect = frameWin.frameElement.getBoundingClientRect(); let [offsetTop, offsetLeft] = this.getIframeContentOffset(frameWin.frameElement); rect.top += frameRect.top + offsetTop; rect.left += frameRect.left + offsetLeft; frameWin = frameWin.parent; } return rect; }, /** * Returns iframe content offset (iframe border + padding). * Note: this function shouldn't need to exist, had the platform provided a * suitable API for determining the offset between the iframe's content and * its bounding client rect. Bug 626359 should provide us with such an API. * * @param aIframe * The iframe. * @returns array [offsetTop, offsetLeft] * offsetTop is the distance from the top of the iframe and the * top of the content document. * offsetLeft is the distance from the left of the iframe and the * left of the content document. */ getIframeContentOffset: function LH_getIframeContentOffset(aIframe) { let style = aIframe.contentWindow.getComputedStyle(aIframe, null); // In some cases, the computed style is null if (!style) { return [0, 0]; } let paddingTop = parseInt(style.getPropertyValue("padding-top")); let paddingLeft = parseInt(style.getPropertyValue("padding-left")); let borderTop = parseInt(style.getPropertyValue("border-top-width")); let borderLeft = parseInt(style.getPropertyValue("border-left-width")); return [borderTop + paddingTop, borderLeft + paddingLeft]; }, /** * Apply the page zoom factor. */ getZoomedRect: function LH_getZoomedRect(aWin, aRect) { // get page zoom factor, if any let zoom = aWin.QueryInterface(Components.interfaces.nsIInterfaceRequestor) .getInterface(Components.interfaces.nsIDOMWindowUtils) .screenPixelsPerCSSPixel; // adjust rect for zoom scaling let aRectScaled = {}; for (let prop in aRect) { aRectScaled[prop] = aRect[prop] * zoom; } return aRectScaled; }, /** * Find an element from the given coordinates. This method descends through * frames to find the element the user clicked inside frames. * * @param DOMDocument aDocument the document to look into. * @param integer aX * @param integer aY * @returns Node|null the element node found at the given coordinates. */ getElementFromPoint: function LH_elementFromPoint(aDocument, aX, aY) { let node = aDocument.elementFromPoint(aX, aY); if (node && node.contentDocument) { if (node instanceof Ci.nsIDOMHTMLIFrameElement) { let rect = node.getBoundingClientRect(); // Gap between the iframe and its content window. let [offsetTop, offsetLeft] = LayoutHelpers.getIframeContentOffset(node); aX -= rect.left + offsetLeft; aY -= rect.top + offsetTop; if (aX < 0 || aY < 0) { // Didn't reach the content document, still over the iframe. return node; } } if (node instanceof Ci.nsIDOMHTMLIFrameElement || node instanceof Ci.nsIDOMHTMLFrameElement) { let subnode = this.getElementFromPoint(node.contentDocument, aX, aY); if (subnode) { node = subnode; } } } return node; }, };