Transform XML tree viewer to blink-in-js implementation.

Source/core/xml/DocumentXMLTreeViewer.js

+// Copyright 2014 The Chromium Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style license that can be
+// found in the LICENSE file.
+
+"use strict";
+
+installClass("Document", function(DocumentPrototype) {
+    // FIXME: The stylesheet should be defined in a separate css file
+    var styleSheet = [
+        "div.header {",
+        "    border-bottom: 2px solid black;",
+        "    padding-bottom: 5px;",
+        "    margin: 10px;",
+        "}",
+        "",
+        "div.collapsible > div.hidden {",
+        "    display:none;",
+        "}",
+        "",
+        ".pretty-print {",
+        "    margin-top: 1em;",
+        "    margin-left: 20px;",
+        "    font-family: monospace;",
+        "    font-size: 13px;",
+        "}",
+        "",
+        "#webkit-xml-viewer-source-xml {",
+        "    display: none;",
+        "}",
+        "",
+        ".collapsible-content {",
+        "    margin-left: 1em;",
+        "}",
+        ".comment {",
+        "    white-space: pre;",
+        "}",
+        "",
+        ".button {",
+        "    -webkit-user-select: none;",
+        "    cursor: pointer;",
+        "    display: inline-block;",
+        "    margin-left: -10px;",
+        "    width: 10px;",
+        "    background-repeat: no-repeat;",
+        "    background-position: left top;",
+        "    vertical-align: bottom;",
+        "}",
+        "",
+        ".collapse-button {",
+        "    background-image: -webkit-canvas(arrowDown);",
+        "    height: 10px;",
+        "}",
+        "",
+        ".expand-button {",
+        "    background-image: -webkit-canvas(arrowRight);",
+        "    height: 11px;",
+        "}"].join('');
+    var nodeParentPairs = [];
+    var tree;
+
+    function prepareWebKitXMLViewer(noStyleMessage)
+    {
+        var html = createHTMLElement('html');
+        var head = createHTMLElement('head');
+        html.appendChild(head);
+        var style = createHTMLElement('style');
+        style.id = 'xml-viewer-style';
+        style.appendChild(document.createTextNode(styleSheet));
+        head.appendChild(style);
+        var body = createHTMLElement('body');
+        html.appendChild(body);
+        var sourceXML = createHTMLElement('div');
+        sourceXML.id = 'webkit-xml-viewer-source-xml';
+        body.appendChild(sourceXML);
+
+        var child;
+        while (child = document.firstChild) {
+            document.removeChild(child);
+            if (child.nodeType != Node.DOCUMENT_TYPE_NODE)
+                sourceXML.appendChild(child);
+        }
+        document.appendChild(html);
+
+        var header = createHTMLElement('div');
+        body.appendChild(header);
+        header.classList.add('header');
+        var headerSpan = createHTMLElement('span');
+        header.appendChild(headerSpan);
+        headerSpan.textContent = noStyleMessage;
+        header.appendChild(createHTMLElement('br'));
+
+        tree = createHTMLElement('div');
+        body.appendChild(tree);
+        tree.classList.add('pretty-print');
+        window.onload = sourceXMLLoaded;
+    }
+
+    function sourceXMLLoaded()
+    {
+        var sourceXML = document.getElementById('webkit-xml-viewer-source-xml');
+        if (!sourceXML)
+            return; // Stop if some XML tree extension is already processing this document
+
+        for (var child = sourceXML.firstChild; child; child = child.nextSibling)
+            nodeParentPairs.push({parentElement: tree, node: child});
+
+        for (var i = 0; i < nodeParentPairs.length; i++)
+            processNode(nodeParentPairs[i].parentElement, nodeParentPairs[i].node);
+
+        drawArrows();
+        initButtons();
+
+        return false;
+    }
+
+    // Tree processing.
+
+    function processNode(parentElement, node)
+    {
+        if (!processNode.processorsMap) {
+            processNode.processorsMap = {};

[PhistucK, 2014/09/02 07:36:45]

Perhaps cache processNode.processorsMap instead of performing this lookup every
time? It is less verbose and more performant.

var map = processNode.processorsMap;
if (!map) {
  map = {};
  processNode.processorsMap = map;
  map[Node.PROCESSING_INSTRUCTION_NODE] = processProcessingInstruction;
  map[Node.ELEMENT_NODE] = processElement;

+            processNode.processorsMap[Node.PROCESSING_INSTRUCTION_NODE] = processProcessingInstruction;
+            processNode.processorsMap[Node.ELEMENT_NODE] = processElement;
+            processNode.processorsMap[Node.COMMENT_NODE] = processComment;
+            processNode.processorsMap[Node.TEXT_NODE] = processText;
+            processNode.processorsMap[Node.CDATA_SECTION_NODE] = processCDATA;
+        }
+        if (processNode.processorsMap[node.nodeType])
+            processNode.processorsMap[node.nodeType].call(this, parentElement, node);
+    }
+
+    function processElement(parentElement, node)
+    {
+        if (!node.firstChild)
+            processEmptyElement(parentElement, node);
+        else {
+            var child = node.firstChild;
+            if (child.nodeType == Node.TEXT_NODE && isShort(child.nodeValue) && !child.nextSibling)
+                processShortTextOnlyElement(parentElement, node);
+            else
+                processComplexElement(parentElement, node);
+        }
+    }
+
+    function processEmptyElement(parentElement, node)
+    {
+        var line = createLine();
+        line.appendChild(createTag(node, false, true));
+        parentElement.appendChild(line);
+    }
+
+    function processShortTextOnlyElement(parentElement, node)
+    {
+        var line = createLine();
+        line.appendChild(createTag(node, false, false));
+        for (var child = node.firstChild; child; child = child.nextSibling)
+            line.appendChild(createText(child.nodeValue));
+        line.appendChild(createTag(node, true, false));
+        parentElement.appendChild(line);
+    }
+
+    function processComplexElement(parentElement, node)
+    {
+        var collapsible = createCollapsible();
+
+        collapsible.expanded.start.appendChild(createTag(node, false, false));

[PhistucK, 2014/09/02 07:36:45]

Same here.

+        for (var child = node.firstChild; child; child = child.nextSibling)
+            nodeParentPairs.push({parentElement: collapsible.expanded.content, node: child});
+        collapsible.expanded.end.appendChild(createTag(node, true, false));
+
+        collapsible.collapsed.content.appendChild(createTag(node, false, false));

[PhistucK, 2014/09/02 07:36:45]

Same here.

+        collapsible.collapsed.content.appendChild(createText('...'));
+        collapsible.collapsed.content.appendChild(createTag(node, true, false));
+        parentElement.appendChild(collapsible);
+    }
+
+    function processComment(parentElement, node)
+    {
+        if (isShort(node.nodeValue)) {
+            var line = createLine();
+            line.appendChild(createComment('<!-- ' + node.nodeValue + ' -->'));
+            parentElement.appendChild(line);
+        } else {
+            var collapsible = createCollapsible();
+
+            collapsible.expanded.start.appendChild(createComment('<!--'));
+            collapsible.expanded.content.appendChild(createComment(node.nodeValue));
+            collapsible.expanded.end.appendChild(createComment('-->'));
+
+            collapsible.collapsed.content.appendChild(createComment('<!--'));
+            collapsible.collapsed.content.appendChild(createComment('...'));
+            collapsible.collapsed.content.appendChild(createComment('-->'));
+            parentElement.appendChild(collapsible);
+        }
+    }
+
+    function processCDATA(parentElement, node)
+    {
+        if (isShort(node.nodeValue)) {
+            var line = createLine();
+            line.appendChild(createText('<![CDATA[ ' + node.nodeValue + ' ]]>'));
+            parentElement.appendChild(line);
+        } else {
+            var collapsible = createCollapsible();
+
+            collapsible.expanded.start.appendChild(createText('<![CDATA['));
+            collapsible.expanded.content.appendChild(createText(node.nodeValue));
+            collapsible.expanded.end.appendChild(createText(']]>'));
+
+            collapsible.collapsed.content.appendChild(createText('<![CDATA['));
+            collapsible.collapsed.content.appendChild(createText('...'));
+            collapsible.collapsed.content.appendChild(createText(']]>'));
+            parentElement.appendChild(collapsible);
+        }
+    }
+
+    function processProcessingInstruction(parentElement, node)
+    {
+        if (isShort(node.nodeValue)) {
+            var line = createLine();
+            line.appendChild(createComment('<?' + node.nodeName + ' ' + node.nodeValue + '?>'));
+            parentElement.appendChild(line);
+        } else {
+            var collapsible = createCollapsible();
+
+            collapsible.expanded.start.appendChild(createComment('<?' + node.nodeName));
+            collapsible.expanded.content.appendChild(createComment(node.nodeValue));
+            collapsible.expanded.end.appendChild(createComment('?>'));
+
+            collapsible.collapsed.content.appendChild(createComment('<?' + node.nodeName));
+            collapsible.collapsed.content.appendChild(createComment('...'));
+            collapsible.collapsed.content.appendChild(createComment('?>'));
+            parentElement.appendChild(collapsible);
+        }
+    }
+
+    function processText(parentElement, node)
+    {
+        parentElement.appendChild(createText(node.nodeValue));
+    }
+
+    // Processing utils.
+
+    function trim(value)
+    {
+        return value.replace(/^\s\s*/, '').replace(/\s\s*$/, '');
+    }
+
+    function isShort(value)
+    {
+        return trim(value).length <= 50;
+    }
+
+    // Tree rendering.
+
+    function createHTMLElement(elementName)
+    {
+        return document.createElementNS('http://www.w3.org/1999/xhtml', elementName)
+    }
+
+    function createCollapsible()
+    {
+        var collapsible = createHTMLElement('div');
+        collapsible.classList.add('collapsible');
+        collapsible.expanded = createHTMLElement('div');
+        collapsible.expanded.classList.add('expanded');
+        collapsible.appendChild(collapsible.expanded);
+
+        collapsible.expanded.start = createLine();
+        collapsible.expanded.start.appendChild(createCollapseButton());
+        collapsible.expanded.appendChild(collapsible.expanded.start);
+
+        collapsible.expanded.content = createHTMLElement('div');
+        collapsible.expanded.content.classList.add('collapsible-content');
+        collapsible.expanded.appendChild(collapsible.expanded.content);
+
+        collapsible.expanded.end = createLine();
+        collapsible.expanded.appendChild(collapsible.expanded.end);
+
+        collapsible.collapsed = createHTMLElement('div');
+        collapsible.collapsed.classList.add('collapsed');
+        collapsible.collapsed.classList.add('hidden');
+        collapsible.appendChild(collapsible.collapsed);
+        collapsible.collapsed.content = createLine();
+        collapsible.collapsed.content.appendChild(createExpandButton());
+        collapsible.collapsed.appendChild(collapsible.collapsed.content);
+
+        return collapsible;
+    }
+
+    function createButton()
+    {
+        var button = createHTMLElement('span');
+        button.classList.add('button');
+        return button;
+    }
+
+    function createCollapseButton(str)
+    {
+        var button = createButton();
+        button.classList.add('collapse-button');
+        return button;
+    }
+
+    function createExpandButton(str)
+    {
+        var button = createButton();
+        button.classList.add('expand-button');
+        return button;
+    }
+
+    function createComment(commentString)
+    {
+        var comment = createHTMLElement('span');
+        comment.classList.add('comment');
+        comment.classList.add('webkit-html-comment');
+        comment.textContent = commentString;
+        return comment;
+    }
+
+    function createText(value)
+    {
+        var text = createHTMLElement('span');
+        text.textContent = trim(value);
+        text.classList.add('text');
+        return text;
+    }
+
+    function createLine()
+    {
+        var line = createHTMLElement('div');
+        line.classList.add('line');
+        return line;
+    }
+
+    function createTag(node, isClosing, isEmpty)
+    {
+        var tag = createHTMLElement('span');
+        tag.classList.add('webkit-html-tag');
+
+        var stringBeforeAttrs = '<';
+        if (isClosing)
+            stringBeforeAttrs += '/';
+        stringBeforeAttrs += node.nodeName;
+        var textBeforeAttrs = document.createTextNode(stringBeforeAttrs);
+        tag.appendChild(textBeforeAttrs);
+
+        if (!isClosing) {
+            for (var i = 0; i < node.attributes.length; i++)
+                tag.appendChild(createAttribute(node.attributes[i]));
+        }
+
+        var stringAfterAttrs = '';
+        if (isEmpty)
+            stringAfterAttrs += '/';
+        stringAfterAttrs += '>';
+        var textAfterAttrs = document.createTextNode(stringAfterAttrs);
+        tag.appendChild(textAfterAttrs);
+
+        return tag;
+    }
+
+    function createAttribute(attributeNode)
+    {
+        var attribute = createHTMLElement('span');
+        attribute.classList.add('webkit-html-attribute');
+
+        var attributeName = createHTMLElement('span');
+        attributeName.classList.add('webkit-html-attribute-name');
+        attributeName.textContent = attributeNode.name;
+
+        var textBefore = document.createTextNode(' ');
+        var textBetween = document.createTextNode('="');
+
+        var attributeValue = createHTMLElement('span');
+        attributeValue.classList.add('webkit-html-attribute-value');
+        attributeValue.textContent = attributeNode.value;
+
+        var textAfter = document.createTextNode('"');
+
+        attribute.appendChild(textBefore);
+        attribute.appendChild(attributeName);
+        attribute.appendChild(textBetween);
+        attribute.appendChild(attributeValue);
+        attribute.appendChild(textAfter);
+        return attribute;
+    }
+
+    // Tree behaviour.
+
+    function drawArrows()
+    {
+        var ctx = document.getCSSCanvasContext("2d", "arrowRight", 10, 11);
+
+        ctx.fillStyle = "rgb(90,90,90)";
+        ctx.beginPath();
+        ctx.moveTo(0, 0);
+        ctx.lineTo(0, 8);
+        ctx.lineTo(7, 4);
+        ctx.lineTo(0, 0);
+        ctx.fill();
+        ctx.closePath();
+
+        var ctx = document.getCSSCanvasContext("2d", "arrowDown", 10, 10);
+
+        ctx.fillStyle = "rgb(90,90,90)";
+        ctx.beginPath();
+        ctx.moveTo(0, 0);
+        ctx.lineTo(8, 0);
+        ctx.lineTo(4, 7);
+        ctx.lineTo(0, 0);
+        ctx.fill();
+        ctx.closePath();
+    }
+
+    function expandFunction(sectionId)
+    {
+        return function()
+        {
+            document.querySelector('#' + sectionId + ' > .expanded').className = 'expanded';
+            document.querySelector('#' + sectionId + ' > .collapsed').className = 'collapsed hidden';
+        };
+    }
+
+    function collapseFunction(sectionId)
+    {
+        return function()
+        {
+            document.querySelector('#' + sectionId + ' > .expanded').className = 'expanded hidden';
+            document.querySelector('#' + sectionId + ' > .collapsed').className = 'collapsed';
+        };
+    }
+
+    function initButtons()
+    {
+        var sections = document.querySelectorAll('.collapsible');
+        for (var i = 0; i < sections.length; i++) {
+            var sectionId = 'collapsible' + i;
+            sections[i].id = sectionId;
+
+            var expandedPart = sections[i].querySelector('#' + sectionId + ' > .expanded');
+            var collapseButton = expandedPart.querySelector('.collapse-button');
+            collapseButton.onclick = collapseFunction(sectionId);
+            collapseButton.onmousedown = handleButtonMouseDown;
+
+            var collapsedPart = sections[i].querySelector('#' + sectionId + ' > .collapsed');
+            var expandButton = collapsedPart.querySelector('.expand-button');
+            expandButton.onclick = expandFunction(sectionId);
+            expandButton.onmousedown = handleButtonMouseDown;
+        }
+
+    }
+
+    function handleButtonMouseDown(e)
+    {
+       // To prevent selection on double click
+       e.preventDefault();
+    }
+
+    DocumentPrototype.transformDocumentToTreeView = function() {
+        prepareWebKitXMLViewer("This XML file does not appear to have any style information associated with it. The document tree is shown below.");
+    }
+});
+