editor/libeditor/SetDocTitleTxn.cpp

   1 /* -*- Mode: C++; tab-width: 2; indent-tabs-mode: nil; c-basic-offset: 2 -*- */
   2 /* This Source Code Form is subject to the terms of the Mozilla Public
   3  * License, v. 2.0. If a copy of the MPL was not distributed with this
   4  * file, You can obtain one at http://mozilla.org/MPL/2.0/. */
   5
   6 #include "SetDocTitleTxn.h"
   7 #include "mozilla/dom/Element.h"        // for Element
   8 #include "nsAString.h"
   9 #include "nsCOMPtr.h"                   // for nsCOMPtr, getter_AddRefs, etc
  10 #include "nsDebug.h"                    // for NS_ENSURE_SUCCESS, etc
  11 #include "nsError.h"                    // for NS_OK, NS_ERROR_FAILURE, etc
  12 #include "nsIDOMCharacterData.h"        // for nsIDOMCharacterData
  13 #include "nsIDOMDocument.h"             // for nsIDOMDocument
  14 #include "nsIDOMElement.h"              // for nsIDOMElement
  15 #include "nsIDOMNode.h"                 // for nsIDOMNode
  16 #include "nsIDOMNodeList.h"             // for nsIDOMNodeList
  17 #include "nsIDOMText.h"                 // for nsIDOMText
  18 #include "nsIDocument.h"                // for nsIDocument
  19 #include "nsIEditor.h"                  // for nsIEditor
  20 #include "nsIHTMLEditor.h"              // for nsIHTMLEditor
  21 #include "nsLiteralString.h"            // for NS_LITERAL_STRING
  22
  23 using namespace mozilla;
  24
  25 // note that aEditor is not refcounted
  26 SetDocTitleTxn::SetDocTitleTxn()
  27   : EditTxn()
  28 , mIsTransient(false)
  29 {
  30 }
  31
  32 NS_IMETHODIMP SetDocTitleTxn::Init(nsIHTMLEditor *aEditor,
  33                                    const nsAString *aValue)
  34
  35 {
  36   NS_ASSERTION(aEditor && aValue, "null args");
  37   if (!aEditor || !aValue) { return NS_ERROR_NULL_POINTER; }
  38
  39   mEditor = aEditor;
  40   mValue = *aValue;
  41
  42   return NS_OK;
  43 }
  44
  45 NS_IMETHODIMP SetDocTitleTxn::DoTransaction(void)
  46 {
  47   return SetDomTitle(mValue);
  48 }
  49
  50 NS_IMETHODIMP SetDocTitleTxn::UndoTransaction(void)
  51 {
  52   // No extra work required; the DOM changes alone are enough
  53   return NS_OK;
  54 }
  55
  56 NS_IMETHODIMP SetDocTitleTxn::RedoTransaction(void)
  57 {
  58   // No extra work required; the DOM changes alone are enough
  59   return NS_OK;
  60 }
  61
  62 nsresult SetDocTitleTxn::SetDomTitle(const nsAString& aTitle)
  63 {
  64   nsCOMPtr<nsIEditor> editor = do_QueryInterface(mEditor);
  65   NS_ENSURE_TRUE(editor, NS_ERROR_FAILURE);
  66   nsCOMPtr<nsIDOMDocument> domDoc;
  67   nsresult res = editor->GetDocument(getter_AddRefs(domDoc));
  68   NS_ENSURE_TRUE(domDoc, NS_ERROR_FAILURE);
  69
  70   nsCOMPtr<nsIDOMNodeList> titleList;
  71   res = domDoc->GetElementsByTagName(NS_LITERAL_STRING("title"), getter_AddRefs(titleList));
  72   NS_ENSURE_SUCCESS(res, res);
  73
  74   // First assume we will NOT really do anything
  75   // (transaction will not be pushed on stack)
  76   mIsTransient = true;
  77
  78   nsCOMPtr<nsIDOMNode>titleNode;
  79   if(titleList)
  80   {
  81     res = titleList->Item(0, getter_AddRefs(titleNode));
  82     NS_ENSURE_SUCCESS(res, res);
  83     if (titleNode)
  84     {
  85       // Delete existing child textnode of title node
  86       // (Note: all contents under a TITLE node are always in a single text node)
  87       nsCOMPtr<nsIDOMNode> child;
  88       res = titleNode->GetFirstChild(getter_AddRefs(child));
  89       if(NS_FAILED(res)) return res;
  90       if(child)
  91       {
  92         // Save current text as the undo value
  93         nsCOMPtr<nsIDOMCharacterData> textNode = do_QueryInterface(child);
  94         if(textNode)
  95         {
  96           textNode->GetData(mUndoValue);
  97
  98           // If title text is identical to what already exists,
  99           // quit now (mIsTransient is now TRUE)
 100           if (mUndoValue == aTitle)
 101             return NS_OK;
 102         }
 103         res = editor->DeleteNode(child);
 104         if(NS_FAILED(res)) return res;
 105       }
 106     }
 107   }
 108
 109   // We didn't return above, thus we really will be changing the title
 110   mIsTransient = false;
 111
 112   // Get the <HEAD> node, create a <TITLE> and insert it under the HEAD
 113   nsCOMPtr<nsIDocument> document = do_QueryInterface(domDoc);
 114   NS_ENSURE_STATE(document);
 115
 116   dom::Element* head = document->GetHeadElement();
 117   NS_ENSURE_STATE(head);
 118
 119   bool     newTitleNode = false;
 120   uint32_t newTitleIndex = 0;
 121
 122   if (!titleNode)
 123   {
 124     // Didn't find one above: Create a new one
 125     nsCOMPtr<nsIDOMElement>titleElement;
 126     res = domDoc->CreateElement(NS_LITERAL_STRING("title"), getter_AddRefs(titleElement));
 127     NS_ENSURE_SUCCESS(res, res);
 128     NS_ENSURE_TRUE(titleElement, NS_ERROR_FAILURE);
 129
 130     titleNode = do_QueryInterface(titleElement);
 131     newTitleNode = true;
 132
 133     // Get index so we append new title node after all existing HEAD children.
 134     newTitleIndex = head->GetChildCount();
 135   }
 136
 137   // Append a text node under the TITLE
 138   //  only if the title text isn't empty
 139   if (titleNode && !aTitle.IsEmpty())
 140   {
 141     nsCOMPtr<nsIDOMText> textNode;
 142     res = domDoc->CreateTextNode(aTitle, getter_AddRefs(textNode));
 143     NS_ENSURE_SUCCESS(res, res);
 144     nsCOMPtr<nsIDOMNode> newNode = do_QueryInterface(textNode);
 145     NS_ENSURE_TRUE(newNode, NS_ERROR_FAILURE);
 146
 147     if (newTitleNode)
 148     {
 149       // Not undoable: We will insert newTitleNode below
 150       nsCOMPtr<nsIDOMNode> resultNode;
 151       res = titleNode->AppendChild(newNode, getter_AddRefs(resultNode));
 152     }
 153     else
 154     {
 155       // This is an undoable transaction
 156       res = editor->InsertNode(newNode, titleNode, 0);
 157     }
 158     NS_ENSURE_SUCCESS(res, res);
 159   }
 160
 161   if (newTitleNode)
 162   {
 163     // Undoable transaction to insert title+text together
 164     res = editor->InsertNode(titleNode, head->AsDOMNode(), newTitleIndex);
 165   }
 166   return res;
 167 }
 168
 169 NS_IMETHODIMP SetDocTitleTxn::GetTxnDescription(nsAString& aString)
 170 {
 171   aString.AssignLiteral("SetDocTitleTxn: ");
 172   aString += mValue;
 173   return NS_OK;
 174 }
 175
 176 NS_IMETHODIMP SetDocTitleTxn::GetIsTransient(bool *aIsTransient)
 177 {
 178   NS_ENSURE_TRUE(aIsTransient, NS_ERROR_NULL_POINTER);
 179   *aIsTransient = mIsTransient;
 180   return NS_OK;
 181 }
 182