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/* * Copyright (C) 2012 Google Inc. * Licensed to The Android Open Source Project. * * 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. */ var BLOCKED_SRC_ATTR = "blocked-src"; // the set of Elements currently scheduled for processing in handleAllImageLoads // this is an Array, but we treat it like a Set and only insert unique items var gImageLoadElements = []; var gScaleInfo; /** * Only revert transforms that do an imperfect job of shrinking content if they fail * to shrink by this much. Expressed as a ratio of: * (original width difference : width difference after transforms); */ var TRANSFORM_MINIMUM_EFFECTIVE_RATIO = 0.7; // Don't ship with this on. var DEBUG_DISPLAY_TRANSFORMS = false; var gTransformText = {}; /** * Returns the page offset of an element. * * @param {Element} element The element to return the page offset for. * @return {left: number, top: number} A tuple including a left and top value representing * the page offset of the element. */ function getTotalOffset(el) { var result = { left: 0, top: 0 }; var parent = el; while (parent) { result.left += parent.offsetLeft; result.top += parent.offsetTop; parent = parent.offsetParent; } return result; } /** * Walks up the DOM starting at a given element, and returns an element that has the * specified class name or null. */ function up(el, className) { var parent = el; while (parent) { if (parent.classList && parent.classList.contains(className)) { break; } parent = parent.parentNode; } return parent || null; } function getCachedValue(div, property, attrName) { var value; if (div.hasAttribute(attrName)) { value = div.getAttribute(attrName); } else { value = div[property]; div.setAttribute(attrName, value); } return value; } function onToggleClick(e) { toggleQuotedText(e.target); measurePositions(); } function toggleQuotedText(toggleElement) { var elidedTextElement = toggleElement.nextSibling; var isHidden = getComputedStyle(elidedTextElement).display == 'none'; toggleElement.innerHTML = isHidden ? MSG_HIDE_ELIDED : MSG_SHOW_ELIDED; elidedTextElement.style.display = isHidden ? 'block' : 'none'; // Revealing the elided text should normalize it to fit-width to prevent // this message from blowing out the conversation width. if (isHidden) { normalizeElementWidths([elidedTextElement]); } } function collapseAllQuotedText() { processQuotedText(document.documentElement, false /* showElided */); } function processQuotedText(elt, showElided) { var i; var elements = elt.getElementsByClassName("elided-text"); var elidedElement, toggleElement; for (i = 0; i < elements.length; i++) { elidedElement = elements[i]; toggleElement = document.createElement("div"); toggleElement.className = "mail-elided-text"; toggleElement.innerHTML = MSG_SHOW_ELIDED; toggleElement.setAttribute("dir", "auto"); toggleElement.onclick = onToggleClick; elidedElement.style.display = 'none'; elidedElement.parentNode.insertBefore(toggleElement, elidedElement); if (showElided) { toggleQuotedText(toggleElement); } } } function isConversationEmpty(bodyDivs) { var i, len; var msgBody; var text; // Check if given divs are empty (in appearance), and disable zoom if so. for (i = 0, len = bodyDivs.length; i < len; i++) { msgBody = bodyDivs[i]; // use 'textContent' to exclude markup when determining whether bodies are empty // (fall back to more expensive 'innerText' if 'textContent' isn't implemented) text = msgBody.textContent || msgBody.innerText; if (text.trim().length > 0) { return false; } } return true; } function normalizeAllMessageWidths() { var expandedBodyDivs; var metaViewport; var contentValues; var isEmpty; expandedBodyDivs = document.querySelectorAll(".expanded > .mail-message-content"); isEmpty = isConversationEmpty(expandedBodyDivs); normalizeElementWidths(expandedBodyDivs); // assemble a working <meta> viewport "content" value from the base value in the // document, plus any dynamically determined options metaViewport = document.getElementById("meta-viewport"); contentValues = [metaViewport.getAttribute("content")]; if (isEmpty) { contentValues.push(metaViewport.getAttribute("data-zoom-off")); } else { contentValues.push(metaViewport.getAttribute("data-zoom-on")); } metaViewport.setAttribute("content", contentValues.join(",")); } /* * Normalizes the width of all elements supplied to the document body's overall width. * Narrower elements are zoomed in, and wider elements are zoomed out. * This method is idempotent. */ function normalizeElementWidths(elements) { var i; var el; var documentWidth; var goalWidth; var origWidth; var newZoom, oldZoom; var outerZoom; var outerDiv; documentWidth = document.body.offsetWidth; goalWidth = WEBVIEW_WIDTH; for (i = 0; i < elements.length; i++) { el = elements[i]; oldZoom = el.style.zoom; // reset any existing normalization if (oldZoom) { el.style.zoom = 1; } origWidth = el.style.width; el.style.width = goalWidth + "px"; transformContent(el, goalWidth, el.scrollWidth); newZoom = documentWidth / el.scrollWidth; if (NORMALIZE_MESSAGE_WIDTHS) { if (el.classList.contains("mail-message-content")) { outerZoom = 1; } else { outerDiv = up(el, "mail-message-content"); outerZoom = outerDiv ? outerDiv.style.zoom : 1; } el.style.zoom = newZoom / outerZoom; } el.style.width = origWidth; } } function transformContent(el, docWidth, elWidth) { var nodes; var i, len; var index; var newWidth = elWidth; var wStr; var touched; // the format of entries in this array is: // entry := [ undoFunction, undoFunctionThis, undoFunctionParamArray ] var actionLog = []; var node; var done = false; var msgId; var transformText; var existingText; var textElement; var start; var beforeWidth; var tmpActionLog = []; if (elWidth <= docWidth) { return; } start = Date.now(); if (el.parentElement.classList.contains("mail-message")) { msgId = el.parentElement.id; transformText = "[origW=" + elWidth + "/" + docWidth; } // Try munging all divs or textareas with inline styles where the width // is wider than docWidth, and change it to be a max-width. touched = false; nodes = ENABLE_MUNGE_TABLES ? el.querySelectorAll("div[style], textarea[style]") : []; touched = transformBlockElements(nodes, docWidth, actionLog); if (touched) { newWidth = el.scrollWidth; console.log("ran div-width munger on el=" + el + " oldW=" + elWidth + " newW=" + newWidth + " docW=" + docWidth); if (msgId) { transformText += " DIV:newW=" + newWidth; } if (newWidth <= docWidth) { done = true; } } if (!done) { // OK, that wasn't enough. Find images with widths and override their widths. nodes = ENABLE_MUNGE_IMAGES ? el.querySelectorAll("img") : []; touched = transformImages(nodes, docWidth, actionLog); if (touched) { newWidth = el.scrollWidth; console.log("ran img munger on el=" + el + " oldW=" + elWidth + " newW=" + newWidth + " docW=" + docWidth); if (msgId) { transformText += " IMG:newW=" + newWidth; } if (newWidth <= docWidth) { done = true; } } } if (!done) { // OK, that wasn't enough. Find tables with widths and override their widths. // Also ensure that any use of 'table-layout: fixed' is negated, since using // that with 'width: auto' causes erratic table width. nodes = ENABLE_MUNGE_TABLES ? el.querySelectorAll("table") : []; touched = addClassToElements(nodes, shouldMungeTable, "munged", actionLog); if (touched) { newWidth = el.scrollWidth; console.log("ran table munger on el=" + el + " oldW=" + elWidth + " newW=" + newWidth + " docW=" + docWidth); if (msgId) { transformText += " TABLE:newW=" + newWidth; } if (newWidth <= docWidth) { done = true; } } } if (!done) { // OK, that wasn't enough. Try munging all <td> to override any width and nowrap set. beforeWidth = newWidth; nodes = ENABLE_MUNGE_TABLES ? el.querySelectorAll("td") : []; touched = addClassToElements(nodes, null /* mungeAll */, "munged", tmpActionLog); if (touched) { newWidth = el.scrollWidth; console.log("ran td munger on el=" + el + " oldW=" + elWidth + " newW=" + newWidth + " docW=" + docWidth); if (msgId) { transformText += " TD:newW=" + newWidth; } if (newWidth <= docWidth) { done = true; } else if (newWidth == beforeWidth) { // this transform did not improve things, and it is somewhat risky. // back it out, since it's the last transform and we gained nothing. undoActions(tmpActionLog); } else { // the transform WAS effective (although not 100%) // copy the temporary action log entries over as normal for (i = 0, len = tmpActionLog.length; i < len; i++) { actionLog.push(tmpActionLog[i]); } } } } // If the transformations shrank the width significantly enough, leave them in place. // We figure that in those cases, the benefits outweight the risk of rendering artifacts. if (!done && (elWidth - newWidth) / (elWidth - docWidth) > TRANSFORM_MINIMUM_EFFECTIVE_RATIO) { console.log("transform(s) deemed effective enough"); done = true; } if (done) { if (msgId) { transformText += "]"; existingText = gTransformText[msgId]; if (!existingText) { transformText = "Message transforms: " + transformText; } else { transformText = existingText + " " + transformText; } gTransformText[msgId] = transformText; window.mail.onMessageTransform(msgId, transformText); if (DEBUG_DISPLAY_TRANSFORMS) { textElement = el.firstChild; if (!textElement.classList || !textElement.classList.contains("transform-text")) { textElement = document.createElement("div"); textElement.classList.add("transform-text"); textElement.style.fontSize = "10px"; textElement.style.color = "#ccc"; el.insertBefore(textElement, el.firstChild); } textElement.innerHTML = transformText + "<br>"; } } console.log("munger(s) succeeded, elapsed time=" + (Date.now() - start)); return; } // reverse all changes if the width is STILL not narrow enough // (except the width->maxWidth change, which is not particularly destructive) undoActions(actionLog); if (actionLog.length > 0) { console.log("all mungers failed, changes reversed. elapsed time=" + (Date.now() - start)); } } function undoActions(actionLog) { for (i = 0, len = actionLog.length; i < len; i++) { actionLog[i][0].apply(actionLog[i][1], actionLog[i][2]); } } function addClassToElements(nodes, conditionFn, classToAdd, actionLog) { var i, len; var node; var added = false; for (i = 0, len = nodes.length; i < len; i++) { node = nodes[i]; if (!conditionFn || conditionFn(node)) { if (node.classList.contains(classToAdd)) { continue; } node.classList.add(classToAdd); added = true; actionLog.push([node.classList.remove, node.classList, [classToAdd]]); } } return added; } function transformBlockElements(nodes, docWidth, actionLog) { var i, len; var node; var wStr; var index; var touched = false; for (i = 0, len = nodes.length; i < len; i++) { node = nodes[i]; wStr = node.style.width || node.style.minWidth; index = wStr ? wStr.indexOf("px") : -1; if (index >= 0 && wStr.slice(0, index) > docWidth) { saveStyleProperty(node, "width", actionLog); saveStyleProperty(node, "minWidth", actionLog); saveStyleProperty(node, "maxWidth", actionLog); node.style.width = "100%"; node.style.minWidth = ""; node.style.maxWidth = wStr; touched = true; } } return touched; } function transformImages(nodes, docWidth, actionLog) { var i, len; var node; var w, h; var touched = false; for (i = 0, len = nodes.length; i < len; i++) { node = nodes[i]; w = node.offsetWidth; h = node.offsetHeight; // shrink w/h proportionally if the img is wider than available width if (w > docWidth) { saveStyleProperty(node, "maxWidth", actionLog); saveStyleProperty(node, "width", actionLog); saveStyleProperty(node, "height", actionLog); node.style.maxWidth = docWidth + "px"; node.style.width = "100%"; node.style.height = "auto"; touched = true; } } return touched; } function saveStyleProperty(node, property, actionLog) { var savedName = "data-" + property; node.setAttribute(savedName, node.style[property]); actionLog.push([undoSetProperty, node, [property, savedName]]); } function undoSetProperty(property, savedProperty) { this.style[property] = savedProperty ? this.getAttribute(savedProperty) : ""; } function shouldMungeTable(table) { return table.hasAttribute("width") || table.style.width; } function hideAllUnsafeImages() { hideUnsafeImages(document.getElementsByClassName("mail-message-content")); } function hideUnsafeImages(msgContentDivs) { var i, msgContentCount; var j, imgCount; var msgContentDiv, image; var images; var showImages; var k = 0; var urls = new Array(); var messageIds = new Array(); for (i = 0, msgContentCount = msgContentDivs.length; i < msgContentCount; i++) { msgContentDiv = msgContentDivs[i]; showImages = msgContentDiv.classList.contains("mail-show-images"); images = msgContentDiv.getElementsByTagName("img"); for (j = 0, imgCount = images.length; j < imgCount; j++) { image = images[j]; var src = rewriteRelativeImageSrc(image); if (src) { urls[k] = src; messageIds[k] = msgContentDiv.parentNode.id; k++; } attachImageLoadListener(image); // TODO: handle inline image attachments for all supported protocols if (!showImages) { blockImage(image); } } } window.mail.onInlineAttachmentsParsed(urls, messageIds); } /** * Changes relative paths to absolute path by pre-pending the account uri. * @param {Element} imgElement Image for which the src path will be updated. * @returns the rewritten image src string or null if the imgElement was not rewritten. */ function rewriteRelativeImageSrc(imgElement) { var src = imgElement.src; // DOC_BASE_URI will always be a unique x-thread:// uri for this particular conversation if (src.indexOf(DOC_BASE_URI) == 0 && (DOC_BASE_URI != CONVERSATION_BASE_URI)) { // The conversation specifies a different base uri than the document src = CONVERSATION_BASE_URI + src.substring(DOC_BASE_URI.length); imgElement.src = src; return src; } // preserve cid urls as is if (src.substring(0, 4) == "cid:") { return src; } return null; }; function attachImageLoadListener(imageElement) { // Reset the src attribute to the empty string because onload will only fire if the src // attribute is set after the onload listener. var originalSrc = imageElement.src; imageElement.src = ''; imageElement.onload = imageOnLoad; imageElement.src = originalSrc; } /** * Handle an onload event for an <img> tag. * The image could be within an elided-text block, or at the top level of a message. * When a new image loads, its new bounds may affect message or elided-text geometry, * so we need to inspect and adjust the enclosing element's zoom level where necessary. * * Because this method can be called really often, and zoom-level adjustment is slow, * we collect the elements to be processed and do them all later in a single deferred pass. */ function imageOnLoad(e) { // normalize the quoted text parent if we're in a quoted text block, or else // normalize the parent message content element var parent = up(e.target, "elided-text") || up(e.target, "mail-message-content"); if (!parent) { // sanity check. shouldn't really happen. return; } // if there was no previous work, schedule a new deferred job if (gImageLoadElements.length == 0) { window.setTimeout(handleAllImageOnLoads, 0); } // enqueue the work if it wasn't already enqueued if (gImageLoadElements.indexOf(parent) == -1) { gImageLoadElements.push(parent); } } // handle all deferred work from image onload events function handleAllImageOnLoads() { normalizeElementWidths(gImageLoadElements); measurePositions(); // clear the queue so the next onload event starts a new job gImageLoadElements = []; } function blockImage(imageElement) { var src = imageElement.src; if (src.indexOf("http://") == 0 || src.indexOf("https://") == 0 || src.indexOf("content://") == 0 || src.indexOf("cid:") == 0) { imageElement.setAttribute(BLOCKED_SRC_ATTR, src); imageElement.src = "data:"; } } function setWideViewport() { var metaViewport = document.getElementById('meta-viewport'); metaViewport.setAttribute('content', 'width=' + WIDE_VIEWPORT_WIDTH); } function restoreScrollPosition() { var scrollYPercent = window.mail.getScrollYPercent(); if (scrollYPercent && document.body.offsetHeight > window.innerHeight) { document.body.scrollTop = Math.floor(scrollYPercent * document.body.offsetHeight); } } function onContentReady(event) { // hack for b/1333356 if (RUNNING_KITKAT_OR_LATER) { restoreScrollPosition(); } window.mail.onContentReady(); } function setupContentReady() { var signalDiv; // PAGE READINESS SIGNAL FOR JELLYBEAN AND NEWER // Notify the app on 'webkitAnimationStart' of a simple dummy element with a simple no-op // animation that immediately runs on page load. The app uses this as a signal that the // content is loaded and ready to draw, since WebView delays firing this event until the // layers are composited and everything is ready to draw. // // This code is conditionally enabled on JB+ by setting the ENABLE_CONTENT_READY flag. if (ENABLE_CONTENT_READY) { signalDiv = document.getElementById("initial-load-signal"); signalDiv.addEventListener("webkitAnimationStart", onContentReady, false); } } // BEGIN Java->JavaScript handlers function measurePositions() { var overlayTops, overlayBottoms; var i; var len; var expandedBody, headerSpacer; var prevBodyBottom = 0; var expandedBodyDivs = document.querySelectorAll(".expanded > .mail-message-content"); // N.B. offsetTop and offsetHeight of an element with the "zoom:" style applied cannot be // trusted. overlayTops = new Array(expandedBodyDivs.length + 1); overlayBottoms = new Array(expandedBodyDivs.length + 1); for (i = 0, len = expandedBodyDivs.length; i < len; i++) { expandedBody = expandedBodyDivs[i]; headerSpacer = expandedBody.previousElementSibling; // addJavascriptInterface handler only supports string arrays overlayTops[i] = prevBodyBottom; overlayBottoms[i] = (getTotalOffset(headerSpacer).top + headerSpacer.offsetHeight); prevBodyBottom = getTotalOffset(expandedBody.nextElementSibling).top; } // add an extra one to mark the top/bottom of the last message footer spacer overlayTops[i] = prevBodyBottom; overlayBottoms[i] = document.documentElement.scrollHeight; window.mail.onWebContentGeometryChange(overlayTops, overlayBottoms); } function unblockImages(messageDomIds) { var i, j, images, imgCount, image, blockedSrc; for (j = 0, len = messageDomIds.length; j < len; j++) { var messageDomId = messageDomIds[j]; var msg = document.getElementById(messageDomId); if (!msg) { console.log("can't unblock, no matching message for id: " + messageDomId); continue; } images = msg.getElementsByTagName("img"); for (i = 0, imgCount = images.length; i < imgCount; i++) { image = images[i]; blockedSrc = image.getAttribute(BLOCKED_SRC_ATTR); if (blockedSrc) { image.src = blockedSrc; image.removeAttribute(BLOCKED_SRC_ATTR); } } } } function setConversationHeaderSpacerHeight(spacerHeight) { var spacer = document.getElementById("conversation-header"); if (!spacer) { console.log("can't set spacer for conversation header"); return; } spacer.style.height = spacerHeight + "px"; measurePositions(); } function setConversationFooterSpacerHeight(spacerHeight) { var spacer = document.getElementById("conversation-footer"); if (!spacer) { console.log("can't set spacer for conversation footer"); return; } spacer.style.height = spacerHeight + "px"; measurePositions(); } function setMessageHeaderSpacerHeight(messageDomId, spacerHeight) { var spacer = document.querySelector("#" + messageDomId + " > .mail-message-header"); setSpacerHeight(spacer, spacerHeight); } function setSpacerHeight(spacer, spacerHeight) { if (!spacer) { console.log("can't set spacer for message with id: " + messageDomId); return; } spacer.style.height = spacerHeight + "px"; measurePositions(); } function setMessageBodyVisible(messageDomId, isVisible, spacerHeight) { var i, len; var visibility = isVisible ? "block" : "none"; var messageDiv = document.querySelector("#" + messageDomId); var collapsibleDivs = document.querySelectorAll("#" + messageDomId + " > .collapsible"); if (!messageDiv || collapsibleDivs.length == 0) { console.log("can't set body visibility for message with id: " + messageDomId); return; } messageDiv.classList.toggle("expanded"); for (i = 0, len = collapsibleDivs.length; i < len; i++) { collapsibleDivs[i].style.display = visibility; } // revealing new content should trigger width normalization, since the initial render // skips collapsed and super-collapsed messages if (isVisible) { normalizeElementWidths(messageDiv.getElementsByClassName("mail-message-content")); } setMessageHeaderSpacerHeight(messageDomId, spacerHeight); } function replaceSuperCollapsedBlock(startIndex) { var parent, block, msg; block = document.querySelector(".mail-super-collapsed-block[index='" + startIndex + "']"); if (!block) { console.log("can't expand super collapsed block at index: " + startIndex); return; } parent = block.parentNode; block.innerHTML = window.mail.getTempMessageBodies(); // process the new block contents in one go before we pluck them out of the common ancestor processQuotedText(block, false /* showElided */); hideUnsafeImages(block.getElementsByClassName("mail-message-content")); msg = block.firstChild; while (msg) { parent.insertBefore(msg, block); msg = block.firstChild; } parent.removeChild(block); disablePostForms(); measurePositions(); } function processNewMessageBody(msgContentDiv) { processQuotedText(msgContentDiv, true /* showElided */); hideUnsafeImages([msgContentDiv]); if (up(msgContentDiv, "mail-message").classList.contains("expanded")) { normalizeElementWidths([msgContentDiv]); } } function replaceMessageBodies(messageIds) { var i; var id; var msgContentDiv; for (i = 0, len = messageIds.length; i < len; i++) { id = messageIds[i]; msgContentDiv = document.querySelector("#" + id + " > .mail-message-content"); // Check if we actually have a div before trying to replace this message body. if (msgContentDiv) { msgContentDiv.innerHTML = window.mail.getMessageBody(id); processNewMessageBody(msgContentDiv); } else { // There's no message div, just skip it. We're in a really busted state. console.log("Mail message content for msg " + id + " to replace not found."); } } disablePostForms(); measurePositions(); } // handle the special case of adding a single new message at the end of a conversation function appendMessageHtml() { var msg = document.createElement("div"); msg.innerHTML = window.mail.getTempMessageBodies(); var body = msg.children[0]; // toss the outer div, it was just to render innerHTML into document.body.insertBefore(body, document.getElementById("conversation-footer")); processNewMessageBody(body.querySelector(".mail-message-content")); disablePostForms(); measurePositions(); } function disablePostForms() { var forms = document.getElementsByTagName('FORM'); var i; var j; var elements; for (i = 0; i < forms.length; ++i) { if (forms[i].method.toUpperCase() === 'POST') { forms[i].onsubmit = function() { alert(MSG_FORMS_ARE_DISABLED); return false; } elements = forms[i].elements; for (j = 0; j < elements.length; ++j) { if (elements[j].type != 'submit') { elements[j].disabled = true; } } } } } // END Java->JavaScript handlers // Do this first to ensure that the readiness signal comes through, // even if a stray exception later occurs. setupContentReady(); collapseAllQuotedText(); hideAllUnsafeImages(); normalizeAllMessageWidths(); //setWideViewport(); // hack for b/1333356 if (!RUNNING_KITKAT_OR_LATER) { restoreScrollPosition(); } disablePostForms(); measurePositions();
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