124265: make nsIEditorStyleSheet more scriptable. Fix is partly me r=cmanske, partly cmanske r=me; all is sr=alecf

editor/composer/src/nsEditorShell.cpp

@@ -237,7 +237,6 @@ GetTreeOwner(nsIDocShell* aDocShell, nsIBaseWindow** aBaseWindow)
 
 nsEditorShell::nsEditorShell()
 :  mMailCompose(PR_FALSE)
-,  mDisplayMode(eDisplayModeNormal)
 ,  mHTMLSourceMode(PR_FALSE)
 ,  mWebShellWindow(nsnull)
 ,  mContentWindow(nsnull)
@@ -321,32 +320,6 @@ nsEditorShell::ResetEditingState()
     editor->PreDestroy();
   }
 
-  // Unload existing stylesheets
-  nsCOMPtr<nsIEditorStyleSheets> styleSheets = do_QueryInterface(mEditor);
-  if (styleSheets)
-  {
-    if (mBaseStyleSheet)
-    {
-      styleSheets->RemoveOverrideStyleSheet(mBaseStyleSheet);
-      mBaseStyleSheet = 0;
-    }
-    if (mEditModeStyleSheet)
-    {
-      styleSheets->RemoveOverrideStyleSheet(mEditModeStyleSheet);
-      mEditModeStyleSheet = 0;
-    }
-    if (mAllTagsModeStyleSheet)
-    {
-      styleSheets->RemoveOverrideStyleSheet(mAllTagsModeStyleSheet);
-      mAllTagsModeStyleSheet = 0;
-    }
-    if (mParagraphMarksStyleSheet)
-    {
-      styleSheets->RemoveOverrideStyleSheet(mParagraphMarksStyleSheet);
-      mParagraphMarksStyleSheet = 0;  
-    }
-  }
-  
   nsresult rv;  
   // now, unregister the selection listener, if there was one
   if (mStateMaintainer)
@@ -519,20 +492,6 @@ nsEditorShell::PrepareDocumentForEditing(nsIDOMWindow* aDOMWindow, nsIURI *aUrl)
     UpdateWindowTitleAndRecentMenu(PR_TRUE);
   }
 
-  nsCOMPtr<nsIEditorStyleSheets> styleSheets = do_QueryInterface(mEditor);
-  if (!styleSheets)
-    return NS_NOINTERFACE;
-
-  // Load style sheet with settings that should never
-  //  change, even in "Browser" mode
-  // We won't unload this, so we don't need to be returned the style sheet pointer
-  
-  
-  styleSheets->ApplyOverrideStyleSheet(NS_LITERAL_STRING("chrome://editor/content/EditorOverride.css"),
-                                       getter_AddRefs(mBaseStyleSheet));
-
-  SetDisplayMode(mDisplayMode);
-
 #ifdef DEBUG
   // Activate the debug menu only in debug builds
   // by removing the "hidden" attribute set "true" in XUL
@@ -1298,130 +1257,14 @@ nsEditorShell::ApplyStyleSheet(const PRUnichar *url)
 
   nsCOMPtr<nsIEditorStyleSheets> styleSheets = do_QueryInterface(mEditor);
   if (styleSheets)
-    result = styleSheets->ApplyStyleSheet(aURL, nsnull);
+    result = styleSheets->ReplaceStyleSheet(aURL);
 
   return result;
 }
 
-// Note: This is not undoable action (on purpose!)
-NS_IMETHODIMP 
-nsEditorShell::SetDisplayMode(PRInt32 aDisplayMode)
-{
-  if (aDisplayMode == eDisplayModeSource)
-  {
-    // We track only display modes that involve style sheet changes
-    //   with mDisplayMode, so use a separate bool for source mode
-    mHTMLSourceMode = PR_TRUE;
-    // The HTML Source display mode is handled in editor.js
-    return NS_OK;
-  }
-  mHTMLSourceMode = PR_FALSE;
-
-  nsCOMPtr<nsIEditorStyleSheets> styleSheets = do_QueryInterface(mEditor);
-  if (!styleSheets) return NS_NOINTERFACE;
-
-  nsCOMPtr<nsIStyleSheet> nsISheet;
-  nsresult res = NS_OK;
-
-  // Extra style sheets to explain optimization testing:
-  // eDisplayModePreview: No extra style sheets
-  // eDisplayModePreview: 1 extra sheet:  mEditModeStyleSheet
-  // eDisplayModeAllTags: 2 extra sheets: mEditModeStyleSheet and mAllTagsModeStyleSheet
-
-  if (aDisplayMode == eDisplayModePreview)
-  {
-    // Disable all extra "edit mode" style sheets 
-    if (mEditModeStyleSheet)
-    {
-      nsISheet = do_QueryInterface(mEditModeStyleSheet);
-      res = nsISheet->SetEnabled(PR_FALSE);
-      if (NS_FAILED(res)) return res;
-    }
-    // Disable ShowAllTags mode if that was the previous mode
-    if (mDisplayMode == eDisplayModeAllTags && mAllTagsModeStyleSheet)
-    {
-      nsISheet = do_QueryInterface(mAllTagsModeStyleSheet);
-      res = nsISheet->SetEnabled(PR_FALSE);
-    }
-  }
-  else if (aDisplayMode == eDisplayModeNormal)
-  {
-    // Don't need to activate if AllTags was last mode
-    if (mDisplayMode != eDisplayModeAllTags)
-    {
-      // If loaded before, enable the sheet
-      if (mEditModeStyleSheet)
-      {
-        nsISheet = do_QueryInterface(mEditModeStyleSheet);
-        res = nsISheet->SetEnabled(PR_TRUE);
-      }
-      else
-      {
-    
-        //Load the editmode style sheet
-        res = styleSheets->ApplyOverrideStyleSheet(NS_LITERAL_STRING("chrome://editor/content/EditorContent.css"),
-                                                   getter_AddRefs(mEditModeStyleSheet));
-      }
-      if (NS_FAILED(res)) return res;
-    }
-
-    // Disable ShowAllTags mode if that was the previous mode
-    if (mDisplayMode == eDisplayModeAllTags && mAllTagsModeStyleSheet)
-    {
-      nsISheet = do_QueryInterface(mAllTagsModeStyleSheet);
-      res = nsISheet->SetEnabled(PR_FALSE);
-    }
-  }
-  else if (aDisplayMode == eDisplayModeAllTags)
-  {
-    // If loaded before, enable the sheet
-    if (mAllTagsModeStyleSheet)
-    {
-      nsISheet = do_QueryInterface(mAllTagsModeStyleSheet);
-      res = nsISheet->SetEnabled(PR_TRUE);
-    }
-    else
-    {
-      // else load it
-      res = styleSheets->ApplyOverrideStyleSheet(NS_LITERAL_STRING("chrome://editor/content/EditorAllTags.css"),
-                                                 getter_AddRefs(mAllTagsModeStyleSheet));
-    }     
-    if (NS_FAILED(res)) return res;
-
-    // We don't need to activate "normal" mode if that was the previous mode
-    if (mDisplayMode != eDisplayModeNormal)
-    {
-      if (mEditModeStyleSheet)
-      {
-        nsISheet = do_QueryInterface(mEditModeStyleSheet);
-        res = nsISheet->SetEnabled(PR_TRUE);
-      }
-      else
-      {
-        res = styleSheets->ApplyOverrideStyleSheet(NS_LITERAL_STRING("chrome://editor/content/EditorContent.css"),
-                                                   getter_AddRefs(mEditModeStyleSheet));
-      }
-    }
-  }
-
-  // Remember the new mode
-  if (NS_SUCCEEDED(res)) mDisplayMode = aDisplayMode;
-  return res;
-}
-
-NS_IMETHODIMP 
-nsEditorShell::GetEditMode(PRInt32 *_retval)
-{
-  if (mHTMLSourceMode)
-    *_retval = eDisplayModeSource;
-  else
-    *_retval = mDisplayMode;
-
-  return NS_OK;
-}
   
 NS_IMETHODIMP 
-nsEditorShell::IsHTMLSourceMode(PRBool *_retval)
+nsEditorShell::GetHTMLSourceMode(PRBool *_retval)
 {
   *_retval = mHTMLSourceMode;
 
@@ -1429,48 +1272,13 @@ nsEditorShell::IsHTMLSourceMode(PRBool *_retval)
 }
 
 NS_IMETHODIMP 
-nsEditorShell::FinishHTMLSource(void)
+nsEditorShell::SetHTMLSourceMode(const PRBool aSourceMode)
 {
-  if (mHTMLSourceMode)
+  mHTMLSourceMode = aSourceMode;
-  {
+
-    // Call the JS command to convert and switch to previous edit mode
-    return DoControllerCommand("cmd_FinishHTMLSource");
-  }
   return NS_OK;
 }
 
-
-NS_IMETHODIMP 
-nsEditorShell::DisplayParagraphMarks(PRBool aShowMarks)
-{
-  nsresult  res = NS_OK;
-
-  nsCOMPtr<nsIEditorStyleSheets> styleSheets = do_QueryInterface(mEditor);
-  if (!styleSheets) return NS_NOINTERFACE;
-  nsCOMPtr<nsIStyleSheet> nsISheet;
-  if (aShowMarks)
-  {
-    // Check if style sheet is already loaded -- just enable it
-    if (mParagraphMarksStyleSheet)
-    {
-      nsISheet = do_QueryInterface(mParagraphMarksStyleSheet);
-      return nsISheet->SetEnabled(PR_TRUE);
-    }
-    //First time used -- load the style sheet
-    nsCOMPtr<nsICSSStyleSheet> styleSheet;
-    res = styleSheets->ApplyOverrideStyleSheet(NS_LITERAL_STRING("chrome://editor/content/EditorParagraphMarks.css"),
-                                                getter_AddRefs(mParagraphMarksStyleSheet));
-  }
-  else if (mParagraphMarksStyleSheet)
-  {
-    // Disable the style sheet
-    nsISheet = do_QueryInterface(mParagraphMarksStyleSheet);
-    res = nsISheet->SetEnabled(PR_FALSE);
-  }
-  
-  return res;
-}
-
 NS_IMETHODIMP 
 nsEditorShell::SetBodyAttribute(const PRUnichar *attr, const PRUnichar *value)
 {

editor/composer/src/nsEditorShell.h

@@ -218,20 +218,6 @@ class nsEditorShell :   public nsIEditorShell,
     // Pointer to localized strings used for UI
     nsCOMPtr<nsIStringBundle>   mStringBundle;
 
-    // Pointer to extra style sheets we load/unload
-    //  for various Edit Modes or for Paragraph Marks
-    nsCOMPtr<nsICSSStyleSheet>  mEditModeStyleSheet;
-    nsCOMPtr<nsICSSStyleSheet>  mAllTagsModeStyleSheet;
-    nsCOMPtr<nsICSSStyleSheet>  mParagraphMarksStyleSheet;
-
-    // The override style sheet that we never unload while editing
-    nsCOMPtr<nsICSSStyleSheet>  mBaseStyleSheet;
-    
-    // Saves the current display mode to reload style sheets
-    //   after loading a url
-    PRInt32 mDisplayMode;
-    // We don't store the HTMLSource mode in mDisplayMode,
-    //  so we need to track it separately
     PRBool  mHTMLSourceMode;
     
     nsIDOMWindowInternal            *mWebShellWindow;        // weak reference

editor/idl/nsIEditorShell.idl

@@ -67,6 +67,11 @@ interface nsIEditorShell : nsISupports
   attribute nsIDOMWindowInternal contentWindow;
   attribute wstring              editorType;
   attribute string               contentsMIMEType;
+
+  /** XXX Temporary: editorShell must know when we are in HTML Source mode
+   *   for proper command disabling in nsComposerCommands.cpp
+   */
+  attribute boolean HTMLSourceMode;
            
   readonly attribute nsIEditor editor;
   
@@ -76,13 +81,6 @@ interface nsIEditorShell : nsISupports
     eDocumentStatusUnmodified,
     eDocumentStatusModified
   };
-
-  enum {
-    eDisplayModePreview,
-    eDisplayModeNormal,
-    eDisplayModeAllTags,
-    eDisplayModeSource
-  };
 %}
   readonly attribute boolean              documentModified;
   readonly attribute boolean              documentIsEmpty;
@@ -507,44 +505,6 @@ interface nsIEditorShell : nsISupports
 
   void ApplyStyleSheet(in wstring url);
 
-  /** Set the display mode for editing
-    * displayMode
-    *       0 (eDisplayModeWYSIWIG) Preview mode
-    *           that looks exactly like the browser display except
-    *           for certain behaviors like cursor style over links, etc.
-    *       1 (eDisplayModeNormal) Use minimal extra CSS style 
-    *           (from override styles in EditorContent.css) 
-    *           to show named anchors, table borders, etc for editing
-    *       2 (eDisplayModeAllTags) Use maximum extra CSS style 
-    *           (from override styles in EditorAllTags.css) 
-    *           to show icon for every HTML tag
-    */
-  void SetDisplayMode(in PRInt32 displayMode);
-
-  /** Get current mode for editing
-    *  Returns:
-    *  0 (eDisplayModePreview,)
-    *  1 (eDisplayModeNormal)
-    *  2 (eDisplayModeAllTags)
-    *  3 (eDisplayModeSource)
-    */
-  PRInt32 GetEditMode();
-  
-  /** For quicker test if we are in HTML Source mode
-    */
-  boolean IsHTMLSourceMode();
-
-  /** Save the current HTML source edit session
-    *  by inserting it into the document,
-    *  replacing existing DOM
-    */
-  void FinishHTMLSource();
-
-  /** Add/remove an overridestyle sheet to show paragraph marks
-    *
-    */
-  void DisplayParagraphMarks(in PRBool showMarks);
-
   /* Output.
    * format is mime type, e.g. text/html;
    * See nsIEditor.h for legal flag values.

editor/idl/nsIEditorStyleSheets.idl

@@ -49,45 +49,76 @@ class nsICSSStyleSheet;
 
 interface nsIEditorStyleSheets : nsISupports
 {
-  /** load and apply the style sheet, specified by aURL, to
+  /** load and apply the style sheet, specified by aURL, to the
-    * the editor's document. This can involve asynchronous
+    * editor's document, replacing the last style sheet added (if any).
-    * network I/O
+    * This can involve asynchronous network I/O.
+    * 
     * @param aURL         The style sheet to be loaded and applied.
-    * @return             the style sheet created from aURL
     */
-  [noscript] nsICSSStyleSheet applyStyleSheet(in AString aURL);
+  void replaceStyleSheet(in AString aURL);
+
+  /** Add the given Style Sheet to the editor's document,
+    * on top of any that are already there.
+    * This is always synchronous.
+    *
+    * @param aURL  The style sheet to be  applied.
+    */
+  void addStyleSheet(in AString aURL);
+
+  /** load and apply the style sheet, specified by aURL, to the
+    * editor's document, replacing the last style sheet added (if any).
+    * This is always synchronous.
+    * 
+    * @param aURL         The style sheet to be loaded and applied.
+    */
+  void replaceOverrideStyleSheet(in AString aURL);
 
   /** load and apply an Override style sheet, specified by aURL, to
-    * the editor's document. 
+    * the editor's document, on top of any that are already there.
     * IMPORTANT: This is assumed to be synchronous:
     *            URL is a local file with no @import used
     * This action is not undoable.
     * It is not intended for use by "user", only editor developers
     *   to change display behavior for editing (like showing special cursors)
     *   that will not be affected by loading other "document" style sheets
-    *   loaded using ApplyStyleSheet.
+    *   loaded using addStyleSheet or replaceStyleSheet.
     *
     * @param aURL         The style sheet to be loaded and applied.
-    * @return             the style sheet created from aURL
     */
-  [noscript] nsICSSStyleSheet applyOverrideStyleSheet(in AString aURL);
+  void addOverrideStyleSheet(in AString aURL);
-
-  /** Add the given Style Sheet to the editor's document
-    * This is always synchronous
-    * @param aSheet  The style sheet to be  applied.
-    */
-  [noscript] void addStyleSheet(in nsICSSStyleSheet aSheet);
 
   /** Remove the given Style Sheet from the editor's document
     * This is always synchronous
-    * @param aSheet  The style sheet to be removed
+    *
+    * @param aURL  The style sheet to be removed
     */
-  [noscript] void removeStyleSheet(in nsICSSStyleSheet aSheet);
+  void removeStyleSheet(in AString aURL);
 
   /** Remove the given Override Style Sheet from the editor's document
     * This is always synchronous
-    * @param aSheet  The style sheet to be removed.
+    *
+    * @param aURL  The style sheet to be removed.
     */
-  [noscript] void removeOverrideStyleSheet(in nsICSSStyleSheet aSheet);
+  void removeOverrideStyleSheet(in AString aURL);
 
+  /** Enable or disable the given Style Sheet from the editor's document
+    * This is always synchronous
+    *
+    * @param aURL  The style sheet to be removed
+    */
+  void enableStyleSheet(in AString aURL, in PRBool aEnable);
+
+  /** Get the nsICSSStyleSheet associated with the given URL.
+    *
+    * @param aURL         The style sheet's URL
+    * @return             the style sheet
+    */
+  [noscript] nsICSSStyleSheet getStyleSheetForURL(in AString aURL);
+
+  /** Get the URL associated with the given nsICSSStyleSheet.
+    *
+    * @param aStyleSheet  The style sheet
+    * @return             the style sheet's URL
+    */
+  [noscript] AString getURLForStyleSheet(in nsICSSStyleSheet aStyleSheet);
 };

editor/libeditor/base/nsEditor.h

@@ -541,7 +541,6 @@ protected:
   nsIViewManager *mViewManager;
   PRInt32         mUpdateCount;
   nsCOMPtr<nsITransactionManager> mTxnMgr;
-  nsCOMPtr<nsICSSStyleSheet> mLastStyleSheet;			// is owning this dangerous?
   nsWeakPtr         mPlaceHolderTxn;     // weak reference to placeholder for begin/end batch purposes
   nsIAtom          *mPlaceHolderName;    // name of placeholder transaction
   PRInt32           mPlaceHolderBatch;   // nesting count for batching

editor/libeditor/html/nsHTMLEditor.cpp

@@ -3397,20 +3397,88 @@ nsHTMLEditor::GetLinkedObjects(nsISupportsArray** aNodeList)
 #pragma mark -
 #endif
 
+NS_IMETHODIMP
+nsHTMLEditor::AddStyleSheet(const nsAString &aURL)
+{
+  // Enable existing sheet if already loaded.
+  if (EnableExistingStyleSheet(aURL))
+    return NS_OK;
+
+  // Lose the previously-loaded sheet so there's nothing to replace
+  // This pattern is different from Override methods because
+  //  we must wait to remove mLastStyleSheetURL and add new sheet
+  //  at the same time (in StyleSheetLoaded callback) so they are undoable together
+  mLastStyleSheetURL.Truncate();
+  return ReplaceStyleSheet(aURL);
+}
 
 NS_IMETHODIMP
-nsHTMLEditor::AddStyleSheet(nsICSSStyleSheet* aSheet)
+nsHTMLEditor::ReplaceStyleSheet(const nsAString& aURL)
 {
-  AddStyleSheetTxn* txn;
+  // Enable existing sheet if already loaded.
-  nsresult rv = CreateTxnForAddStyleSheet(aSheet, &txn);
+  if (EnableExistingStyleSheet(aURL))
+  {
+    // Disable last sheet if not the same as new one
+    if (!mLastStyleSheetURL.IsEmpty() && mLastStyleSheetURL.Equals(aURL))
+        return EnableStyleSheet(mLastStyleSheetURL, PR_FALSE);
+
+    return NS_OK;
+  }
+
+  nsCOMPtr<nsICSSLoader> cssLoader;
+  nsresult rv = GetCSSLoader(aURL, getter_AddRefs(cssLoader));
+  NS_ENSURE_SUCCESS(rv, rv);
+
+  nsCOMPtr<nsIDocument> document;
+  if (!mPresShellWeak) return NS_ERROR_NOT_INITIALIZED;
+  nsCOMPtr<nsIPresShell> ps = do_QueryReferent(mPresShellWeak);
+  if (!ps) return NS_ERROR_NOT_INITIALIZED;
+  rv = ps->GetDocument(getter_AddRefs(document));
+  NS_ENSURE_SUCCESS(rv, rv);;
+  if (!document)     return NS_ERROR_NULL_POINTER;
+
+  nsCOMPtr<nsIURI> uaURI;
+  rv = NS_NewURI(getter_AddRefs(uaURI), aURL);
+  NS_ENSURE_SUCCESS(rv, rv);
+
+  PRBool complete;
+  nsCOMPtr<nsICSSStyleSheet> sheet;
+  rv = cssLoader->LoadAgentSheet(uaURI, *getter_AddRefs(sheet),
+                                 complete, this);
+  NS_ENSURE_SUCCESS(rv, rv);
+
+  if (complete)
+    StyleSheetLoaded(sheet, PR_FALSE);
+
+  //
+  // If not complete, we will be notified later
+  // with a call to StyleSheetLoaded()
+  //
+
+  return NS_OK;
+}
+
+NS_IMETHODIMP
+nsHTMLEditor::RemoveStyleSheet(const nsAString &aURL)
+{
+  nsCOMPtr<nsICSSStyleSheet> sheet;
+  nsresult rv = GetStyleSheetForURL(aURL, getter_AddRefs(sheet));
+  NS_ENSURE_SUCCESS(rv, rv);
+  if (!sheet)
+    return NS_ERROR_UNEXPECTED;
+
+  RemoveStyleSheetTxn* txn;
+  rv = CreateTxnForRemoveStyleSheet(sheet, &txn);
   if (!txn) rv = NS_ERROR_NULL_POINTER;
   if (NS_SUCCEEDED(rv))
   {
     rv = Do(txn);
     if (NS_SUCCEEDED(rv))
-    {
+      mLastStyleSheetURL.Truncate();        // forget it
-      mLastStyleSheet = do_QueryInterface(aSheet);    // save it so we can remove before applying the next one
+
-    }
+    // Remove it from our internal list
+    rv = RemoveStyleSheetFromList(aURL);
+    NS_ENSURE_SUCCESS(rv, rv);
   }
   // The transaction system (if any) has taken ownwership of txns
   NS_IF_RELEASE(txn);
@@ -3419,146 +3487,285 @@ nsHTMLEditor::AddStyleSheet(nsICSSStyleSheet* aSheet)
 }
 
 
-NS_IMETHODIMP
+NS_IMETHODIMP 
-nsHTMLEditor::RemoveStyleSheet(nsICSSStyleSheet* aSheet)
+nsHTMLEditor::AddOverrideStyleSheet(const nsAString& aURL)
 {
-  RemoveStyleSheetTxn* txn;
+  // Enable existing sheet if already loaded.
-  nsresult rv = CreateTxnForRemoveStyleSheet(aSheet, &txn);
+  if (EnableExistingStyleSheet(aURL))
-  if (!txn) rv = NS_ERROR_NULL_POINTER;
+    return NS_OK;
-  if (NS_SUCCEEDED(rv))
+
+  nsCOMPtr<nsICSSLoader> cssLoader;
+  nsresult rv = GetCSSLoader(aURL, getter_AddRefs(cssLoader));
+  NS_ENSURE_SUCCESS(rv, rv);
+
+  nsCOMPtr<nsIURI> uaURI;
+  rv = NS_NewURI(getter_AddRefs(uaURI), aURL);
+  NS_ENSURE_SUCCESS(rv, rv);
+
+  // We use null for the callback and data pointer because
+  //  we MUST ONLY load synchronous local files (no @import)
+  PRBool complete;
+  nsCOMPtr<nsICSSStyleSheet> sheet;
+  rv = cssLoader->LoadAgentSheet(uaURI, *getter_AddRefs(sheet),
+                                 complete, nsnull);
+
+  // Synchronous loads should ALWAYS return completed
+  if (!complete || !sheet)
+    return NS_ERROR_NULL_POINTER;
+
+  nsCOMPtr<nsIStyleSheet> styleSheet;
+  styleSheet = do_QueryInterface(sheet);
+  nsCOMPtr<nsIStyleSet> styleSet;
+
+  nsCOMPtr<nsIPresShell> ps = do_QueryReferent(mPresShellWeak);
+  if (!ps)
+    return NS_ERROR_NOT_INITIALIZED;
+  rv = ps->GetStyleSet(getter_AddRefs(styleSet));
+  NS_ENSURE_SUCCESS(rv, rv);
+  if (!styleSet)
+    return NS_ERROR_NULL_POINTER;
+
+  // Add the override style sheet
+  // (This checks if already exists)
+  styleSet->AppendOverrideStyleSheet(styleSheet);
+
+  // Save doc pointer to be able to use nsIStyleSheet::SetEnabled()
+  nsCOMPtr<nsIDocument> document;
+  rv = ps->GetDocument(getter_AddRefs(document));
+  if (NS_FAILED(rv))
+    return rv;
+  if (!document)
+    return NS_ERROR_NULL_POINTER;
+  styleSheet->SetOwningDocument(document);
+
+  // This notifies document observers to rebuild all frames
+  // (this doesn't affect style sheet because it is not a doc sheet)
+  document->SetStyleSheetDisabledState(styleSheet, PR_FALSE);
+
+  // Save as the last-loaded sheet
+  mLastOverrideStyleSheetURL = aURL;
+
+  //Add URL and style sheet to our lists
+  return AddNewStyleSheetToList(aURL, sheet);
+}
+
+NS_IMETHODIMP
+nsHTMLEditor::ReplaceOverrideStyleSheet(const nsAString& aURL)
+{
+  // Enable existing sheet if already loaded.
+  if (EnableExistingStyleSheet(aURL))
   {
-    rv = Do(txn);
+    // Disable last sheet if not the same as new one
-    if (NS_SUCCEEDED(rv))
+    if (!mLastOverrideStyleSheetURL.IsEmpty() && !mLastOverrideStyleSheetURL.Equals(aURL))
-    {
+      return EnableStyleSheet(mLastOverrideStyleSheetURL, PR_FALSE);
-      mLastStyleSheet = nsnull;        // forget it
+
-    }
+    return NS_OK;
   }
-  // The transaction system (if any) has taken ownwership of txns
+  // Remove the previous sheet
-  NS_IF_RELEASE(txn);
+  if (!mLastOverrideStyleSheetURL.IsEmpty())
-  
+    RemoveOverrideStyleSheet(mLastOverrideStyleSheetURL);
-  return rv;
+
+  return AddOverrideStyleSheet(aURL);
 }
 
 // Do NOT use transaction system for override style sheets
 NS_IMETHODIMP
-nsHTMLEditor::RemoveOverrideStyleSheet(nsICSSStyleSheet* aSheet)
+nsHTMLEditor::RemoveOverrideStyleSheet(const nsAString &aURL)
 {
+  nsCOMPtr<nsICSSStyleSheet> sheet;
+  nsresult rv = GetStyleSheetForURL(aURL, getter_AddRefs(sheet));
+  NS_ENSURE_SUCCESS(rv, rv);
+  if (!sheet)
+    return NS_OK; /// Don't fail if sheet not found
+
   if (!mPresShellWeak) return NS_ERROR_NOT_INITIALIZED;
   nsCOMPtr<nsIPresShell> ps = do_QueryReferent(mPresShellWeak);
   if (!ps) return NS_ERROR_NOT_INITIALIZED;
 
   nsCOMPtr<nsIDocument> document;
-  nsresult rv = ps->GetDocument(getter_AddRefs(document));
+  rv = ps->GetDocument(getter_AddRefs(document));
-  if (NS_FAILED(rv)) return rv;
+  NS_ENSURE_SUCCESS(rv, rv);;
   if (!document)     return NS_ERROR_NULL_POINTER;
 
   nsCOMPtr<nsIStyleSet> styleSet;
   rv = ps->GetStyleSet(getter_AddRefs(styleSet));
-
+  NS_ENSURE_SUCCESS(rv, rv);
-  if (NS_FAILED(rv)) return rv;
   if (!styleSet) return NS_ERROR_NULL_POINTER;
-  nsCOMPtr<nsIStyleSheet> styleSheet = do_QueryInterface(aSheet);
+
+  nsCOMPtr<nsIStyleSheet> styleSheet = do_QueryInterface(sheet);
   if (!styleSheet) return NS_ERROR_NULL_POINTER;
+
   styleSet->RemoveOverrideStyleSheet(styleSheet);
 
   // This notifies document observers to rebuild all frames
   // (this doesn't affect style sheet because it is not a doc sheet)
   document->SetStyleSheetDisabledState(styleSheet, PR_FALSE);
 
+  // Remove it from our internal list
+  return RemoveStyleSheetFromList(aURL);
+}
+
+NS_IMETHODIMP
+nsHTMLEditor::EnableStyleSheet(const nsAString &aURL, PRBool aEnable)
+{
+  nsCOMPtr<nsICSSStyleSheet> sheet;
+  nsresult rv = GetStyleSheetForURL(aURL, getter_AddRefs(sheet));
+  NS_ENSURE_SUCCESS(rv, rv);
+  if (!sheet)
+    return NS_OK; // Don't fail if sheet not found
+
+  nsCOMPtr<nsIStyleSheet> nsISheet = do_QueryInterface(sheet);
+  return nsISheet->SetEnabled(aEnable);
+}
+
+
+PRBool
+nsHTMLEditor::EnableExistingStyleSheet(const nsAString &aURL)
+{
+  nsCOMPtr<nsICSSStyleSheet> sheet;
+  nsresult rv = GetStyleSheetForURL(aURL, getter_AddRefs(sheet));
+  NS_ENSURE_SUCCESS(rv, rv);
+
+  // Enable sheet if already loaded.
+  if (sheet)
+  {
+    nsCOMPtr<nsIStyleSheet> nsISheet = do_QueryInterface(sheet);
+    nsISheet->SetEnabled(PR_TRUE);
+    return PR_TRUE;
+  }
+  return PR_FALSE;
+}
+
+nsresult
+nsHTMLEditor::EnsureStyleSheetArrays()
+{
+  nsresult rv = NS_OK;
+  if (!mStyleSheets)
+    rv = NS_NewISupportsArray(getter_AddRefs(mStyleSheets));
+
+  return rv;
+}
+
+nsresult
+nsHTMLEditor::AddNewStyleSheetToList(const nsAString &aURL,
+                                     nsICSSStyleSheet *aStyleSheet)
+{
+  PRUint32 countSS;
+  nsresult rv = mStyleSheets->Count(&countSS);
+  NS_ENSURE_SUCCESS(rv, rv);
+
+  PRInt32 countU = mStyleSheetURLs.Count();
+
+  if (countU < 0 || countSS != (PRUint32)countU)
+    return NS_ERROR_UNEXPECTED;
+
+  if (!mStyleSheetURLs.AppendString(aURL))
+    return NS_ERROR_UNEXPECTED;
+
+  return mStyleSheets->AppendElement(aStyleSheet);
+}
+
+nsresult
+nsHTMLEditor::RemoveStyleSheetFromList(const nsAString &aURL)
+{
+  nsresult rv = EnsureStyleSheetArrays();
+  NS_ENSURE_SUCCESS(rv, rv);
+
+  // is it already in the list?
+  PRInt32 foundIndex;
+  foundIndex = mStyleSheetURLs.IndexOf(aURL);
+  if (foundIndex < 0)
+    return NS_ERROR_FAILURE;
+
+  // Attempt both removals; if one fails there's not much we can do.
+  if (!mStyleSheets->RemoveElementAt(foundIndex))
+    rv = NS_ERROR_FAILURE;
+  if (!mStyleSheetURLs.RemoveStringAt(foundIndex))
+    rv = NS_ERROR_FAILURE;
+
+  return rv;
+}
+
+NS_IMETHODIMP
+nsHTMLEditor::GetStyleSheetForURL(const nsAString &aURL,
+                                  nsICSSStyleSheet **aStyleSheet)
+{
+  NS_ENSURE_ARG_POINTER(aStyleSheet);
+  *aStyleSheet = 0;
+  nsresult rv = EnsureStyleSheetArrays();
+  NS_ENSURE_SUCCESS(rv, rv);
+
+  // is it already in the list?
+  PRInt32 foundIndex;
+  foundIndex = mStyleSheetURLs.IndexOf(aURL);
+  if (foundIndex < 0)
+    return NS_OK; //No sheet -- don't fail!
+
+  *aStyleSheet = (nsICSSStyleSheet*)mStyleSheets->ElementAt(foundIndex);
+  if (!*aStyleSheet)
+    return NS_ERROR_FAILURE;
+
+  NS_ADDREF(*aStyleSheet);
   return NS_OK;
 }
 
-NS_IMETHODIMP 
+NS_IMETHODIMP
-nsHTMLEditor::ApplyOverrideStyleSheet(const nsAString& aURL, nsICSSStyleSheet **aStyleSheet)
+nsHTMLEditor::GetURLForStyleSheet(nsICSSStyleSheet *aStyleSheet,
+                                  nsAString &aURL)
 {
-  return ApplyDocumentOrOverrideStyleSheet(aURL, PR_TRUE, aStyleSheet);
+  nsresult rv = EnsureStyleSheetArrays();
+  NS_ENSURE_SUCCESS(rv, rv);
+
+  nsCOMPtr<nsISupports> iSupports = do_QueryInterface(aStyleSheet, &rv);
+  NS_ENSURE_SUCCESS(rv, rv);
+    
+  // is it already in the list?
+  PRInt32 foundIndex;
+  rv = mStyleSheets->GetIndexOf(iSupports, &foundIndex);
+  NS_ENSURE_SUCCESS(rv, rv);
+
+  // Don't fail if we don't find it in our list
+  if (foundIndex == -1)
+    return NS_OK;
+
+  // Found it in the list!
+  nsAString* strp = mStyleSheetURLs.StringAt(foundIndex);
+  if (!strp)
+    return NS_ERROR_UNEXPECTED;
+  aURL = *strp;
+  return NS_OK;
 }
 
-NS_IMETHODIMP 
+nsresult
-nsHTMLEditor::ApplyStyleSheet(const nsAString& aURL, nsICSSStyleSheet **aStyleSheet)
+nsHTMLEditor::GetCSSLoader(const nsAString& aURL, nsICSSLoader** aCSSLoader)
 {
-  return ApplyDocumentOrOverrideStyleSheet(aURL, PR_FALSE, aStyleSheet);
+  if (!aCSSLoader)
-}
+    return NS_ERROR_NULL_POINTER;
+  *aCSSLoader = 0;
 
-//Note: Loading a document style sheet is undoable, loading an override sheet is not
+  nsresult rv;
-nsresult 
-nsHTMLEditor::ApplyDocumentOrOverrideStyleSheet(const nsAString& aURL, PRBool aOverride, nsICSSStyleSheet **aStyleSheet)
-{
-  nsresult rv   = NS_OK;
-  nsCOMPtr<nsIURI> uaURL;
 
-  rv = NS_NewURI(getter_AddRefs(uaURL), aURL);
+  nsCOMPtr<nsIDocument> document;
 
-  if (NS_SUCCEEDED(rv)) {
+  if (!mPresShellWeak) return NS_ERROR_NOT_INITIALIZED;
-    nsCOMPtr<nsIDocument> document;
+  nsCOMPtr<nsIPresShell> ps = do_QueryReferent(mPresShellWeak);
+  if (!ps) return NS_ERROR_NOT_INITIALIZED;
+  rv = ps->GetDocument(getter_AddRefs(document));
+  NS_ENSURE_SUCCESS(rv, rv);;
+  if (!document)     return NS_ERROR_NULL_POINTER;
 
-    if (!mPresShellWeak) return NS_ERROR_NOT_INITIALIZED;
+  nsCOMPtr<nsIHTMLContentContainer> container = do_QueryInterface(document);
-    nsCOMPtr<nsIPresShell> ps = do_QueryReferent(mPresShellWeak);
+  if (!container) return NS_ERROR_NULL_POINTER;
-    if (!ps) return NS_ERROR_NOT_INITIALIZED;
-    rv = ps->GetDocument(getter_AddRefs(document));
-    if (NS_FAILED(rv)) return rv;
-    if (!document)     return NS_ERROR_NULL_POINTER;
-
-    nsCOMPtr<nsIHTMLContentContainer> container = do_QueryInterface(document);
-    if (!container) return NS_ERROR_NULL_POINTER;
       
-    nsCOMPtr<nsICSSLoader> cssLoader;
+  nsCOMPtr<nsICSSLoader> cssLoader;
-    nsCOMPtr<nsICSSStyleSheet> cssStyleSheet;
+  nsCOMPtr<nsICSSStyleSheet> cssStyleSheet;
 
-    rv = container->GetCSSLoader(*getter_AddRefs(cssLoader));
+  rv = container->GetCSSLoader(*getter_AddRefs(cssLoader));
-    if (NS_FAILED(rv)) return rv;
+  NS_ENSURE_SUCCESS(rv, rv);;
-    if (!cssLoader)    return NS_ERROR_NULL_POINTER;
+  if (!cssLoader)    return NS_ERROR_NULL_POINTER;
-
+  *aCSSLoader = cssLoader;
-    PRBool complete;
+  NS_ADDREF(*aCSSLoader);
-
+  return NS_OK;
-    if (aOverride)
-    {
-      // We use null for the callback and data pointer because
-      //  we MUST ONLY load synchronous local files (no @import)
-      rv = cssLoader->LoadAgentSheet(uaURL, *getter_AddRefs(cssStyleSheet), complete,
-                                     nsnull);
-
-      // Synchronous loads should ALWAYS return completed
-      if (!complete || !cssStyleSheet)
-        return NS_ERROR_NULL_POINTER;
-
-      nsCOMPtr<nsIStyleSheet> styleSheet;
-      styleSheet = do_QueryInterface(cssStyleSheet);
-      nsCOMPtr<nsIStyleSet> styleSet;
-      rv = ps->GetStyleSet(getter_AddRefs(styleSet));
-      if (NS_FAILED(rv)) return rv;
-      if (!styleSet)     return NS_ERROR_NULL_POINTER;
-
-      // Add the override style sheet
-      // (This checks if already exists)
-      styleSet->AppendOverrideStyleSheet(styleSheet);
-      // Save doc pointer to be able to use nsIStyleSheet::SetEnabled()
-      styleSheet->SetOwningDocument(document);
-
-      // This notifies document observers to rebuild all frames
-      // (this doesn't affect style sheet because it is not a doc sheet)
-      document->SetStyleSheetDisabledState(styleSheet, PR_FALSE);
-    }
-    else 
-    {
-      rv = cssLoader->LoadAgentSheet(uaURL, *getter_AddRefs(cssStyleSheet), complete,
-                                     this);
-      if (NS_FAILED(rv)) return rv;
-      if (complete)
-        ApplyStyleSheetToPresShellDocument(cssStyleSheet,this);
-
-      //
-      // If not complete, we will be notified later
-      // with a call to ApplyStyleSheetToPresShellDocument().
-      //
-    }
-    if (aStyleSheet)
-    {
-      *aStyleSheet = cssStyleSheet;
-      NS_ADDREF(*aStyleSheet);
-    }
-  }
-  return rv;
 }
 
 #ifdef XP_MAC
@@ -3901,44 +4108,47 @@ nsHTMLEditor::GetReconversionString(nsReconversionEventReply* aReply)
 #endif
 
 
-NS_IMETHODIMP
-nsHTMLEditor::ReplaceStyleSheet(nsICSSStyleSheet *aNewSheet)
-{
-  nsresult  rv = NS_OK;
-  
-  nsAutoEditBatch batchIt(this);
-
-  if (mLastStyleSheet)
-  {
-    rv = RemoveStyleSheet(mLastStyleSheet);
-    //XXX: rv is ignored here, why?
-  }
-
-  rv = AddStyleSheet(aNewSheet);
-  
-  return rv;
-}
-
 NS_IMETHODIMP 
-nsHTMLEditor::StyleSheetLoaded(nsICSSStyleSheet*aSheet, PRBool aNotify)
+nsHTMLEditor::StyleSheetLoaded(nsICSSStyleSheet* aSheet, PRBool aNotify)
-{
-  ApplyStyleSheetToPresShellDocument(aSheet, this);
-  return NS_OK;
-}
-
-/* static callback */
-void nsHTMLEditor::ApplyStyleSheetToPresShellDocument(nsICSSStyleSheet* aSheet, void *aData)
 {
   nsresult rv = NS_OK;
+  nsAutoEditBatch batchIt(this);
 
-  nsHTMLEditor *editor = NS_STATIC_CAST(nsHTMLEditor*, aData);
+  if (!mLastStyleSheetURL.IsEmpty())
-  if (editor)
+    RemoveStyleSheet(mLastStyleSheetURL);
+
+  AddStyleSheetTxn* txn;
+  rv = CreateTxnForAddStyleSheet(aSheet, &txn);
+  if (!txn) rv = NS_ERROR_NULL_POINTER;
+  if (NS_SUCCEEDED(rv))
   {
-    rv = editor->ReplaceStyleSheet(aSheet);
+    rv = Do(txn);
-  }
+    if (NS_SUCCEEDED(rv))
-  // XXX: we lose the return value here. Set a flag in the editor?
+    {
-}
+      // Get the URI, then url spec from the sheet
+      nsCOMPtr<nsIStyleSheet> sheet = do_QueryInterface(aSheet);
+      nsCOMPtr<nsIURI> uri;
+      rv = sheet->GetURL(*getter_AddRefs(uri));
+      if (NS_FAILED(rv))
+        return rv;
 
+      nsCAutoString spec;
+      rv = uri->GetSpec(spec);
+      if (NS_FAILED(rv))
+        return rv;
+
+      // Save it so we can remove before applying the next one
+      mLastStyleSheetURL.AssignWithConversion(spec.get());
+
+      // Also save in our arrays of urls and sheets
+      AddNewStyleSheetToList(mLastStyleSheetURL, aSheet);
+    }
+  }
+  // The transaction system (if any) has taken ownwership of txns
+  NS_IF_RELEASE(txn);
+
+  return NS_OK;
+}
 
 #ifdef XP_MAC
 #pragma mark -

editor/libeditor/html/nsHTMLEditor.h

@@ -63,6 +63,8 @@
 #include "nsHTMLCSSUtils.h"
 #include "nsIParserService.h"
 
+#include "nsVoidArray.h"
+
 class nsIDOMKeyEvent;
 class nsITransferable;
 class nsIDOMEventReceiver;
@@ -206,15 +208,15 @@ public:
 
   /* ------------ nsIEditorStyleSheets methods -------------- */
 
-  NS_IMETHOD ApplyStyleSheet(const nsAString & aURL, nsICSSStyleSheet **aStyleSheet);
+  NS_IMETHOD AddStyleSheet(const nsAString & aURL);
-  NS_IMETHOD ApplyOverrideStyleSheet(const nsAString & aURL, nsICSSStyleSheet **aStyleSheet);
+  NS_IMETHOD ReplaceStyleSheet(const nsAString& aURL);
-  /* Above 2 methods call this with appropriate aOverride value 
+  NS_IMETHOD RemoveStyleSheet(const nsAString &aURL);
-   * Not exposed to IDL interface 
+
-  */
+  NS_IMETHOD AddOverrideStyleSheet(const nsAString & aURL);
-  nsresult   ApplyDocumentOrOverrideStyleSheet(const nsAString & aURL, PRBool aOverride, nsICSSStyleSheet **aStyleSheet);
+  NS_IMETHOD ReplaceOverrideStyleSheet(const nsAString& aURL);
-  NS_IMETHOD AddStyleSheet(nsICSSStyleSheet* aSheet);
+  NS_IMETHOD RemoveOverrideStyleSheet(const nsAString &aURL);
-  NS_IMETHOD RemoveStyleSheet(nsICSSStyleSheet* aSheet);
+
-  NS_IMETHOD RemoveOverrideStyleSheet(nsICSSStyleSheet* aSheet);
+  NS_IMETHOD EnableStyleSheet(const nsAString& aURL, PRBool aEnable);
 
   /* ------------ nsIEditorMailSupport methods -------------- */
 
@@ -451,6 +453,25 @@ public:
                            PRBool aListOrCellNotEmpty,
                            PRBool aSafeToAskFrames,
                            PRBool *aSeenBR);
+
+  // Stylesheet-related methods that aren't part of nsIEditorStyleSheets.
+  nsresult AddCSSStyleSheet(nsICSSStyleSheet* aSheet);
+  nsresult GetCSSLoader(const nsAString& aURL, nsICSSLoader** aCSSLoader);
+
+  // Returns TRUE if sheet was loaded, false if it wasn't
+  PRBool   EnableExistingStyleSheet(const nsAString& aURL);
+
+  // Dealing with the internal style sheet lists:
+  nsresult EnsureStyleSheetArrays();
+  NS_IMETHOD GetStyleSheetForURL(const nsAString &aURL,
+                               nsICSSStyleSheet **_retval);
+  NS_IMETHOD GetURLForStyleSheet(nsICSSStyleSheet *aStyleSheet, nsAString &aURL);
+
+  // Add a url + known style sheet to the internal lists:
+  nsresult AddNewStyleSheetToList(const nsAString &aURL,
+                                  nsICSSStyleSheet *aStyleSheet);
+
+  nsresult RemoveStyleSheetFromList(const nsAString &aURL);
                        
 protected:
 
@@ -471,13 +492,6 @@ protected:
     */
   NS_IMETHOD GetLayoutObject(nsIDOMNode *aInNode, nsISupports **aOutLayoutObject);
 
-  /* StyleSheet load callback */
-  static void ApplyStyleSheetToPresShellDocument(nsICSSStyleSheet* aSheet, void *aData);
-
-  /* remove the old style sheet, and apply the supplied one */
-  NS_IMETHOD ReplaceStyleSheet(nsICSSStyleSheet *aNewSheet);
-
-
   // Return TRUE if aElement is a table-related elemet and caret was set
   PRBool SetCaretInTableCell(nsIDOMElement* aElement);
   PRBool IsElementInBody(nsIDOMElement* aElement);
@@ -767,14 +781,25 @@ protected:
   PRBool   mCachedUnderlineStyle;
   nsString mCachedFontName;
 
+  // Used to disable HTML formatting commands during HTML source editing
+  PRBool   mCanEditHTML;
+
   // Used by GetFirstSelectedCell and GetNextSelectedCell
   PRInt32  mSelectedCellIndex;
 
   nsCOMPtr<nsIRangeUtils> mRangeHelper;
 
+  nsString mLastStyleSheetURL;
+  nsString mLastOverrideStyleSheetURL;
+
   PRBool mCSSAware;
   nsHTMLCSSUtils *mHTMLCSSUtils;
 
+  // Maintain a list of associated style sheets and their urls.
+  nsStringArray mStyleSheetURLs;
+  nsCOMPtr<nsISupportsArray> mStyleSheets;
+  PRInt32 mNumStyleSheets;
+
   // Maintain a static parser service ...
   static nsCOMPtr<nsIParserService> sParserService;
   // ... which means that we need an instance count to know when to delete it

editor/ui/composer/content/ComposerCommands.js

@@ -2121,7 +2121,7 @@ var nsRevertCommand =
       // Reload page if first button (Revert) was pressed
       if(result == 0)
       {
-        SetEditMode(PreviousNonSourceDisplayMode);
+        SetEditMode(gPreviousNonSourceDisplayMode);
         window.editorShell.LoadUrl(GetDocumentUrl());
       }
     }
@@ -3222,7 +3222,7 @@ var nsHTMLSourceModeCommand =
 {
   isCommandEnabled: function(aCommand, dummy)
   {
-    return (window.editorShell && window.editorShell.documentEditable && gIsHTMLEditor);
+    return (window.editorShell && window.editorShell.documentEditable && isHTMLEditor());
   },
 
   getCommandStateParams: function(aCommand, aParams, aRefCon) {},
@@ -3230,8 +3230,8 @@ var nsHTMLSourceModeCommand =
 
   doCommand: function(aCommand)
   {
-    if (gEditorDisplayMode != DisplayModeSource)
+    if (gEditorDisplayMode != gDisplayModeSource)
-      SetEditMode(DisplayModeSource);
+      SetEditMode(gDisplayModeSource);
   }
 };
 
@@ -3239,7 +3239,7 @@ var nsPreviewModeCommand =
 {
   isCommandEnabled: function(aCommand, dummy)
   {
-    return (window.editorShell && window.editorShell.documentEditable && gIsHTMLEditor);
+    return (window.editorShell && window.editorShell.documentEditable && isHTMLEditor());
   },
 
   getCommandStateParams: function(aCommand, aParams, aRefCon) {},
@@ -3248,8 +3248,8 @@ var nsPreviewModeCommand =
   doCommand: function(aCommand)
   {
     FinishHTMLSource();
-    if (gEditorDisplayMode != DisplayModePreview)
+    if (gEditorDisplayMode != gDisplayModePreview)
-      SetEditMode(DisplayModePreview);
+      SetEditMode(gDisplayModePreview);
   }
 };
 

editor/ui/composer/content/editor.js

@@ -46,15 +46,18 @@ var gEditor;
 var editorShell;   // XXX THIS NEEDS TO DIE
 var documentModified;
 var prefAuthorString = "";
-var NormalMode = 1;
+
-var PreviewMode = 2;
 // These must match enums in nsIEditorShell.idl:
-var DisplayModePreview = 0;
+const gDisplayModePreview = 0;
-var DisplayModeNormal = 1;
+const gDisplayModeNormal = 1;
-var DisplayModeAllTags = 2;
+const gDisplayModeAllTags = 2;
-var DisplayModeSource = 3;
+const gDisplayModeSource = 3;
-var PreviousNonSourceDisplayMode = 1;
+const gNormalStyleSheet = "chrome://editor/content/EditorContent.css";
-var gEditorDisplayMode = 1;  // Normal Editor mode
+const gAllTagsStyleSheet = "chrome://editor/content/EditorAllTags.css";
+const gParagraphMarksStyleSheet = "chrome://editor/content/EditorParagraphMarks.css";
+
+var gPreviousNonSourceDisplayMode = 1;
+var gEditorDisplayMode = -1;
 var WebCompose = false;     // Set true for Web Composer, leave false for Messenger Composer
 var docWasModified = false;  // Check if clean document, if clean then unload when user "Opens"
 var gContentWindow = 0;
@@ -195,7 +198,7 @@ function PageIsEmptyAndUntouched()
 
 function IsInHTMLSourceMode()
 {
-  return (gEditorDisplayMode == DisplayModeSource);
+  return (gEditorDisplayMode == gDisplayModeSource);
 }
 
 // are we editing HTML (i.e. neither in HTML source mode, nor editing a text file)
@@ -347,6 +350,9 @@ var DocumentStateListener =
     // Add mouse click watcher if right type of editor
     if (isHTMLEditor())
       addEditorClickEventListener();
+
+    // Start in "Normal" edit mode
+    SetDisplayMode(gDisplayModeNormal);
   },
 
     // note that the editor seems to be gone at this point 
@@ -1429,7 +1435,7 @@ function EditorClick(event)
   // In Show All Tags Mode,
   // single click selects entire element,
   //  except for body and table elements
-  if (event.target && isHTMLEditor() && gEditorDisplayMode == DisplayModeAllTags)
+  if (event.target && isHTMLEditor() && gEditorDisplayMode == gDisplayModeAllTags)
   {
     try
     {
@@ -1517,7 +1523,7 @@ function SetEditMode(mode)
   if (!SetDisplayMode(mode))
     return;
 
-  if (mode == DisplayModeSource)
+  if (mode == gDisplayModeSource)
   {
     // Display the DOCTYPE as a non-editable string above edit area
     var domdoc;
@@ -1564,7 +1570,7 @@ function SetEditMode(mode)
     gSourceContentWindow.addEventListener("input", oninputHTMLSource, false);
     gHTMLSourceChanged = false;
   }
-  else if (previousMode == DisplayModeSource)
+  else if (previousMode == gDisplayModeSource)
   {
     // Only rebuild document if a change was made in source window
     if (gHTMLSourceChanged)
@@ -1650,7 +1656,7 @@ function CancelHTMLSource()
   // Don't convert source text back into the DOM document
   gSourceContentWindow.value = "";
   gHTMLSourceChanged = false;
-  SetDisplayMode(PreviousNonSourceDisplayMode);
+  SetDisplayMode(gPreviousNonSourceDisplayMode);
 }
 
 function FinishHTMLSource()
@@ -1667,8 +1673,8 @@ function FinishHTMLSource()
       {
         AlertWithTitle(GetString("Alert"), GetString("NoHeadTag"));
         //cheat to force back to Source Mode
-        gEditorDisplayMode = DisplayModePreview;
+        gEditorDisplayMode = gDisplayModePreview;
-        SetDisplayMode(DisplayModeSource);
+        SetDisplayMode(gDisplayModeSource);
         throw Components.results.NS_ERROR_FAILURE;
       }
 
@@ -1677,15 +1683,15 @@ function FinishHTMLSource()
       {
         AlertWithTitle(GetString("Alert"), GetString("NoBodyTag"));
         //cheat to force back to Source Mode
-        gEditorDisplayMode = DisplayModePreview;
+        gEditorDisplayMode = gDisplayModePreview;
-        SetDisplayMode(DisplayModeSource);
+        SetDisplayMode(gDisplayModeSource);
         throw Components.results.NS_ERROR_FAILURE;
       }
     }
   }
 
   // Switch edit modes -- converts source back into DOM document
-  SetEditMode(PreviousNonSourceDisplayMode);
+  SetEditMode(gPreviousNonSourceDisplayMode);
 }
 
 function CollapseItem(id, collapse)
@@ -1710,23 +1716,49 @@ function SetDisplayMode(mode)
 
   gEditorDisplayMode = mode;
 
-  // Save the last non-source mode so we can cancel source editing easily
+  // Load/unload appropriate override style sheet
-  if (mode != DisplayModeSource)
+  try {
-    PreviousNonSourceDisplayMode = mode;
+    var editor = GetCurrentEditor();
 
-  // Editorshell does the style sheet loading/unloading
+    if (mode == gDisplayModePreview)
-  editorShell.SetDisplayMode(mode);
+    {
+      // Disable all extra "edit mode" style sheets 
+      editor.enableStyleSheet(gNormalStyleSheet, false);
+      editor.enableStyleSheet(gAllTagsStyleSheet, false);
+    }
+    else if (mode == gDisplayModeNormal)
+    {
+      editor.addOverrideStyleSheet(gNormalStyleSheet);
+
+      // Disable ShowAllTags mode if that was the previous mode
+      if (gPreviousNonSourceDisplayMode == gDisplayModeAllTags)
+        editor.enableStyleSheet(gAllTagsStyleSheet, false);
+    }
+    else if (mode == gDisplayModeAllTags)
+    {
+      editor.addOverrideStyleSheet(gNormalStyleSheet);
+      editor.addOverrideStyleSheet(gAllTagsStyleSheet);
+    }
+  } catch(e) {}
+
+  //XXX We still have to tell editorShell if we are in HTMLSource mode
+  //    because commands in nsComposerCommands.cpp can't access JS command results yet
+  editorShell.HTMLSourceMode = (mode == gDisplayModeSource);
+
+  // Save the last non-source mode so we can cancel source editing easily
+  if (mode != gDisplayModeSource)
+    gPreviousNonSourceDisplayMode = mode;
 
   // Set the UI states
   var selectedTab = null;
-  if (mode == DisplayModePreview) selectedTab = gPreviewModeButton;
+  if (mode == gDisplayModePreview) selectedTab = gPreviewModeButton;
-  if (mode == DisplayModeNormal) selectedTab = gNormalModeButton;
+  if (mode == gDisplayModeNormal) selectedTab = gNormalModeButton;
-  if (mode == DisplayModeAllTags) selectedTab = gTagModeButton;
+  if (mode == gDisplayModeAllTags) selectedTab = gTagModeButton;
-  if (mode == DisplayModeSource) selectedTab = gSourceModeButton;
+  if (mode == gDisplayModeSource) selectedTab = gSourceModeButton;
   if (selectedTab)
     document.getElementById("EditModeTabs").selectedItem = selectedTab;
 
-  if (mode == DisplayModeSource)
+  if (mode == gDisplayModeSource)
   {
     // Switch to the sourceWindow (second in the deck)
     gContentWindowDeck.setAttribute("selectedIndex","1");
@@ -1766,16 +1798,16 @@ function SetDisplayMode(mode)
   var menuID;
   switch(mode)
   {
-    case DisplayModePreview:
+    case gDisplayModePreview:
       menuID = "viewPreviewMode";
       break;
-    case DisplayModeNormal:
+    case gDisplayModeNormal:
       menuID = "viewNormalMode";
       break;
-    case DisplayModeAllTags:
+    case gDisplayModeAllTags:
       menuID = "viewAllTagsMode";
       break;
-    case DisplayModeSource:
+    case gDisplayModeSource:
       menuID = "viewSourceMode";
       break;
   }
@@ -1795,8 +1827,10 @@ function EditorToggleParagraphMarks()
     //  so if "checked" is true now, it was just switched to that mode
     var checked = menuItem.getAttribute("checked");
     try {
-      // XXX There's no non-editorshell equivalent yet for this:
+      if (checked == "true")
-      editorShell.DisplayParagraphMarks(checked == "true");
+        GetCurrentEditor().addOverrideStyleSheet(gParagraphMarksStyleSheet);
+      else
+        GetCurrentEditor().enableStyleSheet(gParagraphMarksStyleSheet, false);
     }
     catch(e) { return; }
   }