gecko-dev/suite/browser/pageInfo.js

/* -*- Mode: Java; tab-width: 4; indent-tabs-mode: nil; c-basic-offset: 2 -*- */
/* ***** BEGIN LICENSE BLOCK *****
 * Version: NPL 1.1/GPL 2.0/LGPL 2.1
 *
 * The contents of this file are subject to the Netscape 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/NPL/
 *
 * 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 mozilla.org code.
 *
 * The Initial Developer of the Original Code is Netscape
 * Communications Corporation.  Portions created by Netscape are
 * Copyright (C) 1998 Netscape Communications Corporation. All
 * Rights Reserved.
 *
 * Contributor(s): smorrison@gte.com
 *   Terry Hayes <thayes@netscape.com>
 *   Daniel Brooks <db48x@yahoo.com>
 *
 * 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 NPL, 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 NPL, the GPL or the LGPL.
 *
 * ***** END LICENSE BLOCK *****
*/

//******** define a js object to implement nsITreeView
function pageInfoTreeView(columnids, copycol)
{
  // columnids is an array of strings indicating the names of the columns, in order
  this.columnids = columnids;
  this.colcount = columnids.length

  // copycol is the index number for the column that we want to add to 
  // the copy-n-paste buffer when the user hits accel-c
  this.copycol = copycol;
  this.rows = 0;
  this.tree = null;
  this.data = new Array;
  this.selection = null;
  this.sortcol = null;
  this.sortdir = 0;
  this.initialized = 0; // set this to one once we fill in all the rows
}

pageInfoTreeView.prototype = {
  set rowCount(c) { throw "rowCount is a readonly property"; },
  get rowCount() { return this.rows; },

  setTree: function(tree) 
  {
    this.tree = tree;
  },

  getCellText: function(row, column)
  {
    var colidx = 0;
    // loop through the list of column names to find the index to the column 
    // we should be worrying about. very much a hack, but what can you do?
    while(colidx < this.colcount && column != this.columnids[colidx])
      colidx++;

    // row can be null, but js arrays are 0-indexed.
    // colidx cannot be null, but can be larger than the number
    // of columns in the array (when column is a string not in 
    // this.columnids.) In this case it's the fault of
    // whoever typoed while calling this function.
    return this.data[row][colidx] || "";
  },

  setCellText: function(row, column, value) 
  {
    var colidx = 0;
    // loop through the list of column names to find the index 
    // to the column the should be worrying about. very much a hack, but
    // what can you do? 
    // XXX: I think there's a better way to do this now...
    while(colidx < this.colcount && column != this.columnids[colidx])
      colidx++;
    this.data[row][colidx] = value;
  },

  addRow: function(row)
  {
    this.rows = this.data.push(row);
  },

  addRows: function(rows)
  {
    var length = rows.length;
    for(var i = 0; i < length; i++)
      this.rows = this.data.push(rows[i]);
  },

  rowCountChanged: function(index, count)
  {
    this.tree.rowCountChanged(index, count);
  },

  invalidate: function()
  {
    this.tree.invalidate();
  },

  clear: function()
  {
    this.data = new Array;
    this.rows = 0;
  },

  handleCopy: function(row)
  {
    return (row < 0 || copycol < 0) ? "" : (this.data[row][this.copycol] || "");
  },

  performActionOnRow: function(action, row)
  {
    if (action == "copy")
    {
      var data = this.handleCopy(row)
      this.tree.treeBody.parentNode.setAttribute("copybuffer", data);
    }
  },

  getRowProperties: function(row, column, prop) { },
  getCellProperties: function(row, prop) { },
  getColumnProperties: function(column, elem, prop) { },
  isContainer: function(index) { return false; },
  isContainerOpen: function(index) { return false; },
  isSeparator: function(index) { return false; },
  isSorted: function() { },
  canDropOn: function(index) { return false; },
  canDropBeforeAfter: function(index, before) { return false; },
  drop: function(row, orientation) { return false; },
  getParentIndex: function(index) { return 0; },
  hasNextSibling: function(index, after) { return false; },
  getLevel: function(index) { return 0; },
  getImageSrc: function(row, column) { },
  getProgressMode: function(row, column) { },
  getCellValue: function(row, column) { },
  toggleOpenState: function(index) { },
  cycleHeader: function(col, elem) { },
  selectionChanged: function() { },
  cycleCell: function(row, column) { },
  isEditable: function(row, column) { return false; },
  performAction: function(action) { },
  performActionOnCell: function(action, row, column) { }
};

// mmm, yummy. global variables.
var theWindow = null;
var theDocument = null;

// column number to copy from, second argument to pageInfoTreeView's constructor
const COPYCOL_NONE = -1;
const COPYCOL_META_CONTENT = 1;
const COPYCOL_FORM_ACTION = 2;
const COPYCOL_LINK_ADDRESS = 1;
const COPYCOL_IMAGE_ADDRESS = 0;

// one nsITreeView for each tree in the window
var metaView = new pageInfoTreeView(["meta-name","meta-content"], COPYCOL_META_CONTENT);
var formView = new pageInfoTreeView(["form-name","form-method","form-action","form-node"], COPYCOL_FORM_ACTION);
var fieldView = new pageInfoTreeView(["field-label","field-field","field-type","field-value"], COPYCOL_NONE);
var linkView = new pageInfoTreeView(["link-name","link-address","link-type"], COPYCOL_LINK_ADDRESS);
var imageView = new pageInfoTreeView(["image-address","image-type","image-alt","image-node", "image-bg"], COPYCOL_IMAGE_ADDRESS);

// localized strings (will be filled in when the document is loaded)
// this isn't all of them, these are just the ones that would otherwise have been loaded inside a loop
var gStrings = {}
var theBundle;

const DRAGSERVICE_CONTRACTID    = "@mozilla.org/widget/dragservice;1";
const TRANSFERABLE_CONTRACTID   = "@mozilla.org/widget/transferable;1";
const ARRAY_CONTRACTID          = "@mozilla.org/supports-array;1";
const STRING_CONTRACTID         = "@mozilla.org/supports-string;1";

// a number of services I'll need later
// the cache services
const nsICacheService = Components.interfaces.nsICacheService;
const cacheService = Components.classes["@mozilla.org/network/cache-service;1"].getService(nsICacheService);
var httpCacheSession = cacheService.createSession("HTTP", 0, true);
httpCacheSession.doomEntriesIfExpired = false;
var ftpCacheSession = cacheService.createSession("FTP", 0, true);
ftpCacheSession.doomEntriesIfExpired = false;

// scriptable date formater, for pretty printing dates
const nsIScriptableDateFormat = Components.interfaces.nsIScriptableDateFormat;
var dateService = Components.classes["@mozilla.org/intl/scriptabledateformat;1"].getService(nsIScriptableDateFormat);

// clipboard helper
try
{
  const gClipboardHelper = Components.classes["@mozilla.org/widget/clipboardhelper;1"].getService(Components.interfaces.nsIClipboardHelper);
}
catch(e)
{
  // do nothing, later code will handle the error
}

// namespaces, don't need all of these yet...
const XLinkNS = "http://www.w3.org/1999/xlink";
const XULNS   = "http://www.mozilla.org/keymaster/gatekeeper/there.is.only.xul";
const XMLNS   = "http://www.w3.org/XML/1998/namespace";
const XHTMLNS = "http://www.w3.org/1999/xhtml";

/* Overlays register init functions here.
 *   Add functions to call by invoking "onLoadRegistry.append(XXXLoadFunc);"
 *   The XXXLoadFunc should be unique to the overlay module, and will be
 *   invoked as "XXXLoadFunc();"
 */
var onLoadRegistry = [ ];
 
/* Called when PageInfo window is loaded.  Arguments are:
 *  window.arguments[0] - document to use for source (null=Page Info, otherwise Frame Info)
 *  window.arguments[1] - tab name to display first (may be null)
*/
function onLoadPageInfo()
{
  //dump("===============================================================================\n");

  theBundle = document.getElementById("pageinfobundle");
  gStrings.unknown = theBundle.getString("unknown");
  gStrings.notSet = theBundle.getString("notset");
  gStrings.emptyString = theBundle.getString("emptystring");
  gStrings.linkAnchor = theBundle.getString("linkAnchor");
  gStrings.linkArea = theBundle.getString("linkArea");
  gStrings.linkSubmit = theBundle.getString("linkSubmit");
  gStrings.linkSubmission = theBundle.getString("linkSubmission");
  gStrings.linkRel = theBundle.getString("linkRel");
  gStrings.linkStylesheet = theBundle.getString("linkStylesheet");
  gStrings.linkRev = theBundle.getString("linkRev");
  gStrings.linkX = theBundle.getString("linkX");
  gStrings.mediaImg = theBundle.getString("mediaImg");
  gStrings.mediaBGImg = theBundle.getString("mediaBGImg");
  gStrings.mediaApplet = theBundle.getString("mediaApplet");
  gStrings.mediaObject = theBundle.getString("mediaObject");
  gStrings.mediaEmbed = theBundle.getString("mediaEmbed");
  gStrings.mediaLink = theBundle.getString("mediaLink");
  gStrings.mediaInput = theBundle.getString("mediaInput");

  var docTitle = "";
  if("arguments" in window && window.arguments.length >= 1 && window.arguments[0])
  {
    theWindow = null;
    theDocument = window.arguments[0];
    docTitle = theBundle.getString("frameInfo.title");
  } 
  else 
  {
    if ("gBrowser" in window.opener)
      theWindow = window.opener.gBrowser.contentWindow;
    else
      theWindow = window.opener.frames[0];
    theDocument = theWindow.document;

    docTitle = theBundle.getString("pageInfo.title");
  }

  document.title = docTitle;

  // do the easy stuff first
  makeGeneralTab();

  /* Call registered overlay init functions */
  for (x in onLoadRegistry)
  {
    onLoadRegistry[x]();
  }

  /* Select the requested tab, if the name is specified */
  if ("arguments" in window && window.arguments.length > 1)
  {
    var tabName = window.arguments[1];

    if (tabName)
    {
      var tabControl = document.getElementById("tabbox");
      var tab = document.getElementById(tabName);

      if (tabControl && tab)
      {
        tabControl.selectedTab = tab;
      }
    }
  }
}

function doHelpButton() {
  var tabControl = document.getElementById("tabbox");
  switch (tabControl.selectedTab.id) {
    case "generalTab":
      helpdoc = "pageinfo_general";
      break;
    case "formsTab":
      helpdoc = "pageinfo_forms";
      break;
    case "linksTab":
      helpdoc = "pageinfo_links";
      break;
    case "mediaTab":
      helpdoc = "pageinfo_media";
      break;
    case "securityTab":
      helpdoc = "pageinfo_security";
      break;
    case "p3pTab":
      helpdoc = "pageinfo_privacy";
      break;
    default:
      helpdoc = "pageinfo_general";
      break;
  }
  openHelp(helpdoc);  
}
 
function makeGeneralTab()
{
  var title = (theDocument.title) ? theBundle.getFormattedString("pageTitle", [theDocument.title]) : theBundle.getString("noPageTitle");
  document.getElementById("titletext").value = title;

  var url = theDocument.location;
  document.getElementById("urltext").value = url;

  var mode = ("compatMode" in theDocument && theDocument.compatMode == "BackCompat") ? theBundle.getString("generalQuirksMode") : theBundle.getString("generalStrictMode");
  document.getElementById("modetext").value = mode;

  var referrer = (theDocument.referrer) ? theDocument.referrer : theBundle.getString("generalNoReferrer");
  document.getElementById('refertext').value = referrer;

  // find out the mime type
  var mimeType = theDocument.contentType || gStrings.unknown;
  document.getElementById("typetext").value = mimeType;
  
  // get the meta tags
  var metaNodes = theDocument.getElementsByTagName("meta");
  var metaTree = document.getElementById("metatree");

  metaTree.treeBoxObject.view = metaView;

  var length = metaNodes.length;
  for (var i = 0; i < length; i++)
    metaView.addRow([metaNodes[i].name || metaNodes[i].httpEquiv, metaNodes[i].content]);

  metaView.rowCountChanged(0, length);
  
  // get the document characterset
  var encoding = theDocument.characterSet;
  document.getElementById("encodingtext").value = encoding;

  // get the date of last modification
  var modifiedText = formatDate(theDocument.lastModified, gStrings.notSet);
  document.getElementById("modifiedtext").value = modifiedText;
  
  // get cache info
  var sourceText = theBundle.getString("generalNotCached");
  var expirationText = theBundle.getString("generalNoExpiration");
  var sizeText = gStrings.unknown;

  var pageSize = 0; 
  var kbSize = 0;
  var expirationTime = 0;

  try
  {
    var cacheEntryDescriptor = httpCacheSession.openCacheEntry(url, Components.interfaces.nsICache.ACCESS_READ, false);
    if(cacheEntryDescriptor)
    { 
      switch(cacheEntryDescriptor.deviceID)
      {
        case "disk":
          sourceText = theBundle.getString("generalDiskCache");
          break;
        case "memory":
          sourceText = theBundle.getString("generalMemoryCache");
          break;
        default:
          sourceText = cacheEntryDescriptor.deviceID;
          break;
      }

      pageSize = cacheEntryDescriptor.dataSize;
      kbSize = pageSize / 1024;
      sizeText = theBundle.getFormattedString("generalSize", [Math.round(kbSize*100)/100, pageSize]);

      expirationText = formatDate(cacheEntryDescriptor.expirationTime*1000, gStrings.notSet);
    }
  }
  catch(ex)
  {
    try
    {
      cacheEntryDescriptor = ftpCacheSession.openCacheEntry(url, Components.interfaces.nsICache.ACCESS_READ, false);
      if (cacheEntryDescriptor)
      {
        switch(cacheEntryDescriptor.deviceID)
        {
          case "disk":
            sourceText = theBundle.getString("generalDiskCache");
            break;
          case "memory":
            sourceText = theBundle.getString("generalMemoryCache");
            break;
          default:
            sourceText = cacheEntryDescriptor.deviceID;
            break;
        }

        pageSize = cacheEntryDescriptor.dataSize;
        kbSize = pageSize / 1024;
        sizeText = theBundle.getFormattedString("generalSize", [Math.round(kbSize*100)/100, pageSize]);

        expirationText = formatDate(cacheEntryDescriptor.expirationTime*1000, gStrings.notSet);
      }
    }
    catch(ex2)
    {
      sourceText = theBundle.getString("generalNotCached");
    }
  }
  document.getElementById("sourcetext").value = sourceText;
  document.getElementById("expirestext").value = expirationText;
  document.getElementById("sizetext").value = sizeText;
}

//******** Generic Build-a-tab
function makeTabs(aDocument, aWindow)
{
  if (formView.initialized || linkView.initialized || imageView.initialized)
    return;

  if (aWindow && aWindow.frames.length > 0)
  {
    var num = aWindow.frames.length;
    for (var i = 0; i < num; i++)
      makeTabs(aWindow.frames[i].document, aWindow.frames[i]);  // recurse through the frames
  }

  var formTree = document.getElementById("formtree");
  var linkTree = document.getElementById("linktree");
  var imageTree = document.getElementById("imagetree");

  formTree.treeBoxObject.view = formView;
  linkTree.treeBoxObject.view = linkView;
  imageTree.treeBoxObject.view = imageView;
  
  var iterator = aDocument.createTreeWalker(aDocument, NodeFilter.SHOW_ELEMENT, grabAll, true);
  
  while (iterator.nextNode())
    ; // it'll never be executed anyway, since grabAll never 
      // accepts any nodes

  formView.rowCountChanged(0, formView.rowCount);
  formView.selection.select(0);
  formView.initialized = 1;

  linkView.rowCountChanged(0, linkView.rowCount);
  linkView.selection.select(0);
  linkView.initialized = 1;

  imageView.rowCountChanged(0, imageView.rowCount);
  imageView.selection.select(0);
  imageView.initialized = 1;
}

function grabAll(elem)
{
  var linktext;

  // check for background images, any node may have one
  var url = elem.ownerDocument.defaultView.getComputedStyle(elem, "").getPropertyCSSValue("background-image");
  if (url && url.primitiveType == CSSPrimitiveValue.CSS_URI)
  {
    imageView.addRow([url.getStringValue(), gStrings.mediaBGImg, gStrings.notSet, elem, true]);
  }

  // one switch to rule them all
  // XXX: these tests should use regexes to be a little more lenient wrt whitespace, see bug 177047
  switch (elem.nodeName.toLowerCase())
  {
    // form tab
    case "form":
      formView.addRow([elem.name, elem.method, elem.getAttribute("action"), elem]);  // use getAttribute() because of bug 122128
      break;

    // link tab
    case "a":
      linktext = getValueText(elem);
      linkView.addRow([linktext, elem.href, gStrings.linkAnchor, elem.target]);
      break;
    case "area":
      linkView.addRow([elem.alt, elem.href, gStrings.linkArea, elem.target]);
      break;
    case "input":
      linkView.addRow([elem.value || gStrings.linkSubmit, elem.form.getAttribute("action"), gStrings.linkSubmission, elem.form.getAttribute("target")]); // use getAttribute() due to bug 122128
      break;
    case "link":
      if (elem.rel)
      {
        var rel = elem.rel.toLowerCase();
        if (rel == "icon")
        {
          imageView.addRow([elem.href, gStrings.mediaLink, "", elem]);
          break;
        }
        if (rel == "stylesheet" || rel == "alternate stylesheet")
          linktext = gStrings.linkStylesheet;
        else
          linktext = gStrings.linkRel;
      }
      else
        linktext = gStrings.linkRev;
      linkView.addRow([elem.rel || elem.rev, elem.href, linktext, elem.target]);
      break;

    // media tab
    case "img":
      imageView.addRow([elem.src, gStrings.mediaImg, (elem.hasAttribute("alt")) ? elem.alt : gStrings.notSet, elem]);
      break;
    case "input":
      if (elem.type == "image")
        imageView.addRow([elem.src, gStrings.mediaInput, (elem.hasAttribute("alt")) ? elem.alt : gStrings.notSet, elem]);
      break;
    case "applet":
      //XXX When Java is enabled, the DOM model for <APPLET> is broken. Bug #59686.
      // Also, some reports of a crash with Java in Media tab (bug 136535), and mixed
      // content from two hosts (bug 136539) so just drop applets from Page Info when
      // Java is on. For the 1.0.1 branch; get a real fix on the trunk.
      if (!navigator.javaEnabled())
        imageView.addRow([elem.code || elem.object, gStrings.mediaApplet, "",elem]);
      break;
    case "object":
      imageView.addRow([elem.data, gStrings.mediaObject, getValueText(elem), elem]);
      break;
    case "embed":
      imageView.addRow([elem.src, gStrings.mediaEmbed, "", elem]);
      break;
    default:
      if (elem.hasAttributeNS(XLinkNS, "href"))
      {
        linktext = getValueText(elem);
        linkView.addRow([linktext, elem.href, gStrings.linkX, ""]);
      }
      break;
  }
  return NodeFilter.FILTER_SKIP;
}

//******** Form Stuff
function onFormSelect()
{
  var formTree = document.getElementById("formtree");
  if (!formView.rowCount) return;

  if (formView.selection.count == 1)
  {
    var formPreview = document.getElementById("formpreview");
    fieldView.clear();
    formPreview.treeBoxObject.view = fieldView;

    var clickedRow = formView.selection.currentIndex;
    var form = formView.getCellText(clickedRow, "form-node");

    var ft = null;
    if (form.name)
      ft = theBundle.getFormattedString("formTitle", [form.name]);
    else
      ft = theBundle.getString("formUntitled");

    document.getElementById("formname").value = ft || theBundle.getString("formUntitled");
    document.getElementById("formenctype").value = form.encoding || theBundle.getString("default");
    document.getElementById("formtarget").value = form.target || theBundle.getString("formDefaultTarget");

    var formfields = form.elements;

    var length = formfields.length;
    var i = 0;

    var checked = theBundle.getString("formChecked");
    var unchecked = theBundle.getString("formUnchecked");    

    for (i = 0; i < length; i++)
    {
      var elem = formfields[i];

      if(elem.nodeName.toLowerCase() == "button")
        fieldView.addRow(["", elem.name, elem.type, getValueText(elem)]);
      else
      {
        var val = (elem.type == "password") ? theBundle.getString("formPassword") : elem.value;
        fieldView.addRow(["", elem.name, elem.type, val]);
      }
    }

    var labels = form.getElementsByTagName("label");
    var llength = labels.length;

    for (i = 0; i < llength; i++)
    {
      var whatfor = labels[i].hasAttribute("for") ?
        theDocument.getElementById(labels[i].getAttribute("for")) :
        findFirstControl(labels[i]);

      if (whatfor && (whatfor.form == form)) {
        var labeltext = getValueText(labels[i]);
        for (var j = 0; j < length; j++)
          if (formfields[j] == whatfor)
            fieldView.setCellText(j, "field-label", labeltext);
      }
    }

    fieldView.rowCountChanged(0, length);
  }
}

function findFirstControl(node)
{
  function FormControlFilter() 
  {
    switch (node.nodeName.toLowerCase())
    {
      case "input":
      case "select":
      case "button":
      case "textarea":
      case "object":
        return NodeFilter.FILTER_ACCEPT;
      default:
        return NodeFilter.FILTER_SKIP;
    }
  }

  var iterator = theDocument.createTreeWalker(node, NodeFilter.SHOW_ELEMENT, FormControlFilter, true);

  return iterator.nextNode();
}

//******** Link Stuff
function openURL(target)
{
  var url = target.parentNode.childNodes[2].value;
  window.open(url, "_blank", "chrome");
}

function onBeginLinkDrag(event,urlField,descField)
{
  if (event.originalTarget.localName != "treechildren")
    return;

  var tree = event.target;
  if (!("treeBoxObject" in tree))
    tree = tree.parentNode;

  var row = {};
  var col = {};
  var elt = {};
  tree.treeBoxObject.getCellAt(event.clientX, event.clientY, row, col, elt);
  if (row.value == -1)
    return;

  // Getting drag-system needed services
  var dragService = Components.classes[DRAGSERVICE_CONTRACTID].getService().QueryInterface(Components.interfaces.nsIDragService);
  var transArray = Components.classes[ARRAY_CONTRACTID].createInstance(Components.interfaces.nsISupportsArray);
  if (!transArray)
    return;
  var trans = Components.classes[TRANSFERABLE_CONTRACTID].createInstance(Components.interfaces.nsITransferable);
  if (!trans)
    return;
  
  // Adding URL flavor
  trans.addDataFlavor("text/x-moz-url");
  var url = tree.treeBoxObject.view.getCellText(row.value, urlField);
  var desc = tree.treeBoxObject.view.getCellText(row.value, descField);
  var stringURL = Components.classes[STRING_CONTRACTID].createInstance(Components.interfaces.nsISupportsString);
  stringURL.data = url + "\n"+desc;
  trans.setTransferData("text/x-moz-url", stringURL, stringURL.data.length * 2 );
  transArray.AppendElement(trans.QueryInterface(Components.interfaces.nsISupports));

  dragService.invokeDragSession(event.target, transArray, null, dragService.DRAGDROP_ACTION_NONE);
}

//******** Image Stuff
function getSource(item)
{
  // Return the correct source without strict warnings
  if (item.href != null)
    return item.href;
  if (item.src != null)
    return item.src;
  return null;
}

function getSelectedImage(tree)
{
  if (!imageView.rowCount) return null;

  // Only works if only one item is selected
  var clickedRow = tree.treeBoxObject.selection.currentIndex;
  return imageView.getCellText(clickedRow, "image-node");
}

function saveMedia()
{
  var tree = document.getElementById("imagetree");
  var item = getSelectedItem(tree);
  var url = getAbsoluteURL(getSource(item), item);

  if (url)
    saveURL(url, null, 'SaveImageTitle', false );
}

function onImageSelect()
{
  var tree = document.getElementById("imagetree");
  var saveAsButton = document.getElementById("imagesaveasbutton");

  if (tree.treeBoxObject.selection.count == 1)
  {
    makePreview(tree.treeBoxObject.selection.currentIndex);
    saveAsButton.setAttribute("disabled", "false");
  }
  else
    saveAsButton.setAttribute("disabled", "true");
}

function makePreview(row)
{
  var item = getSelectedImage(document.getElementById("imagetree"));
  var url = imageView.getCellText(row, "image-address");
  var isBG = imageView.getCellText(row, "image-bg");

  document.getElementById("imageurltext").value = url;
  document.getElementById("imagetitletext").value = item.title || gStrings.notSet;

  var altText = null;
  if (item.hasAttribute("alt") && ("alt" in item))
    altText = item.alt;
  else if (!isBG)
    altText = getValueText(item);
  if (altText == null)
    altText = gStrings.notSet;
  var textbox=document.getElementById("imagealttext");
  
  // IMO all text that is not really the value text should go in italics
  // What if somebody has <img alt="Not specified">? =)
  // We can't use textbox.style because of bug 7639
  if (altText=="") {
      textbox.value = gStrings.emptyString;
      textbox.setAttribute("style","font-style:italic");
  } else {
      textbox.value = altText;
      textbox.setAttribute("style","font-style:inherit");
  }
  document.getElementById("imagelongdesctext").value = ("longDesc" in item && item.longDesc) || gStrings.notSet;

  // find out the mime type
  var mimeType = gStrings.unknown;
  if (item.nodeName.toLowerCase() != "input")
    mimeType = ("type" in item && item.type) ||
               ("codeType" in item && item.codeType) ||
               ("contentType" in item && item.contentType) ||
               gStrings.unknown;
  document.getElementById("imagetypetext").value = mimeType;

  // get cache info
  var sourceText = theBundle.getString("generalNotCached");
  var expirationText = gStrings.unknown;
  var sizeText = gStrings.unknown;

  var pageSize = 0; 
  var kbSize = 0;
  var expirationTime = 0;
  var expirationDate = null;

  try
  {
    var cacheEntryDescriptor = httpCacheSession.openCacheEntry(url, Components.interfaces.nsICache.ACCESS_READ, false);   // open for READ, in non-blocking mode
    if (cacheEntryDescriptor)
    {
      switch(cacheEntryDescriptor.deviceID)
      {
        case "disk":
          sourceText = theBundle.getString("generalDiskCache");
          break;
        case "memory":
          sourceText = theBundle.getString("generalMemoryCache");
          break;
        default:
          sourceText = cacheEntryDescriptor.deviceID;
          break;
      }

      pageSize = cacheEntryDescriptor.dataSize;
      kbSize = pageSize / 1024;
      sizeText = theBundle.getFormattedString("generalSize", [Math.round(kbSize*100)/100, pageSize]);

      expirationText = formatDate(cacheEntryDescriptor.expirationTime*1000, gStrings.notSet);
    }
  }
  catch(ex)
  {
    try
    {
      cacheEntryDescriptor = ftpCacheSession.openCacheEntry(url, Components.interfaces.nsICache.ACCESS_READ, false);   // open for READ, in non-blocking mode
      if (cacheEntryDescriptor)
      {
        switch(cacheEntryDescriptor.deviceID)
        {
          case "disk":
            sourceText = theBundle.getString("generalDiskCache");
            break;
          case "memory":
            sourceText = theBundle.getString("generalMemoryCache");
            break;
          default:
            sourceText = cacheEntryDescriptor.deviceID;
            break;
        }

        pageSize = cacheEntryDescriptor.dataSize;
        kbSize = pageSize / 1024;
        sizeText = theBundle.getFormattedString("generalSize", [Math.round(kbSize*100)/100, pageSize]);

        expirationText = formatDate(cacheEntryDescriptor.expirationTime*1000, gStrings.notSet);
      }
    }
    catch(ex2)
    {
      sourceText = theBundle.getString("generalNotCached");
    }
  }
  document.getElementById("imagesourcetext").value = sourceText;
  document.getElementById("imageexpirestext").value = expirationText;
  document.getElementById("imagesizetext").value = sizeText;

  var imageContainer = document.getElementById("theimagecontainer");
  var oldImage = document.getElementById("thepreviewimage");

  var nn = item.nodeName.toLowerCase();
  var regex = new RegExp("^(https?|ftp|file|gopher)://");
  var absoluteURL = getAbsoluteURL(url, item);
  var isProtocolAllowed = regex.test(absoluteURL); 
  var newImage = new Image();
  newImage.setAttribute("id", "thepreviewimage");
  if ((nn == "link" || nn == "input" || nn == "img" || isBG) &&
      isProtocolAllowed) 
  {
    newImage.src = absoluteURL;
    if ("width" in item && item.width)
      newImage.width = item.width;
    if ("height" in item && item.height)
      newImage.height = item.height;
  } 
  else 
  {
    // fallback image for protocols not allowed (e.g., data: or javascript:) 
    // or elements not [yet] handled (e.g., object, embed). XXX blank??
    newImage.src = "resource:///res/loading-image.gif";
    newImage.width = 40;
    newImage.height = 40;
  }

  var width = ("width" in item && item.width) || ("width" in newImage && newImage.width) || "0";
  var height = ("height" in item && item.height) || ("height" in newImage && newImage.height) || "0";
  document.getElementById("imagewidth").value = theBundle.getFormattedString("mediaWidth", [width]);
  document.getElementById("imageheight").value = theBundle.getFormattedString("mediaHeight", [height]);

  imageContainer.removeChild(oldImage);
  imageContainer.appendChild(newImage);
}


//******** Other Misc Stuff
// Modified from the Links Panel v2.3, http://segment7.net/mozilla/links/links.html
// parse a node to extract the contents of the node
// linkNode doesn't really _have_ to be link
function getValueText(linkNode)
{
  var valueText = "";
  
  var length = linkNode.childNodes.length;
  for (var i = 0; i < length; i++)
  {
    var childNode = linkNode.childNodes[i];
    var nodeType = childNode.nodeType;
    if (nodeType == Node.TEXT_NODE)
      valueText += " " + childNode.nodeValue;
    else if (nodeType == Node.ELEMENT_NODE)
    {
      if (childNode.nodeName.toLowerCase() == "img")
        valueText += " " + getAltText(childNode);
      else
        valueText += " " + getValueText(childNode);
    }
  }

  return stripWS(valueText);
}

// Copied from the Links Panel v2.3, http://segment7.net/mozilla/links/links.html
// traverse the tree in search of an img or area element and grab its alt tag
function getAltText(node)
{
  var altText = "";
  
  if (node.alt)
    return node.alt;
  var length = node.childNodes.length;
  for (var i = 0; i < length; i++)
    if ((altText = getAltText(node.childNodes[i]) != undefined))  // stupid js warning...
      return altText;
  return "";
}

// Copied from the Links Panel v2.3, http://segment7.net/mozilla/links/links.html
// strip leading and trailing whitespace, and replace multiple consecutive whitespace characters with a single space
function stripWS(text)
{
  var middleRE = /\s+/g;
  var endRE = /(^\s+)|(\s+$)/g;

  text = text.replace(middleRE, " ");
  return text.replace(endRE, "");
}

function formatDate(datestr, unknown)
{
  var date = new Date(datestr);
  return (date.valueOf()) ? dateService.FormatDateTime("", dateService.dateFormatLong, dateService.timeFormatSeconds, date.getFullYear(), date.getMonth()+1, date.getDate(), date.getHours(), date.getMinutes(), date.getSeconds()) : unknown;
}

/*
 * Takes care of XMLBase and <base>
 * url is the possibly relative url.
 * node is the node where the url was given (needed for XMLBase)
 *
 * This function is called in many places as a workaround for bug 72524
 * Once bug 72522 is fixed this code should use the Node.baseURI attribute
 *
 * for node==null or url=="", empty string is returned
 *
 * This is basically just copied from http://lxr.mozilla.org/seamonkey/source/xpfe/browser/resources/content/metadata.js
 */

function getAbsoluteURL(url, node)
{
  if (!url || !node)
    return "";
  var urlArr = new Array(url);

  var doc = node.ownerDocument;
  if (node.nodeType == Node.ATTRIBUTE_NODE)
    node = node.ownerElement;

  while (node && node.nodeType == Node.ELEMENT_NODE) 
  {
    var att = node.getAttributeNS(XMLNS, "base");
    if (att != "")
      urlArr.unshift(att);

    node = node.parentNode;
  }

  // Look for a <base>.
  var baseTags = doc.getElementsByTagNameNS(XHTMLNS, "base");

  if (baseTags && baseTags.length) 
  {
    urlArr.unshift(baseTags[baseTags.length - 1].getAttribute("href"));
  }

  // resolve everything from bottom up, starting with document location
  var ioService = Components.classes["@mozilla.org/network/io-service;1"].getService(Components.interfaces.nsIIOService);
  var URL = ioService.newURI(doc.location.href, null, null);

  for (var i=0; i<urlArr.length; i++) 
  {
    URL.spec = URL.resolve(urlArr[i]);
  }

  return URL.spec;
}

function doCopy(event)
{
  if (!gClipboardHelper) 
    return;

  var elem = event.originalTarget;
  if (elem && "treeBoxObject" in elem)
    elem.treeBoxObject.view.performActionOnRow("copy", elem.currentIndex);

  var text = elem.getAttribute("copybuffer");
  if (text) 
    gClipboardHelper.copyString(text);
}