This CL makes switching the target back to the original language

revert the translation.
It also simplifies the page translator logic. We are initializing the PageTranslator states when a new page is translated.  Further translations reuse the text nodes already retrieved.
Also an unused method has been removed from RenderView.

BUG=36073
TEST=See bug. Thoroughly test the translation feature.

Review URL: http://codereview.chromium.org/647030

git-svn-id: svn://svn.chromium.org/chrome/trunk/src@39384 0039d316-1c4b-4281-b951-d872f2087c98

5 files changed, 52 insertions, 49 deletions

diff --git a/chrome/browser/translate/translate_infobars_delegates.cc b/chrome/browser/translate/translate_infobars_delegates.cc
index 9f76e85..ad0b8d5 100644
--- a/chrome/browser/translate/translate_infobars_delegates.cc
+++ b/chrome/browser/translate/translate_infobars_delegates.cc
@@ -97,8 +97,7 @@ void TranslateInfoBarDelegate::GetAvailableTargetLanguages(
 }
 
 void TranslateInfoBarDelegate::Translate() {
-  if (original_lang_index_ != target_lang_index_)
-    tab_contents_->TranslatePage(original_lang_code(), target_lang_code());
+  tab_contents_->TranslatePage(original_lang_code(), target_lang_code());
 }
 
 void TranslateInfoBarDelegate::TranslationDeclined() {
diff --git a/chrome/renderer/render_view.cc b/chrome/renderer/render_view.cc
index 6c287d0..953c734 100644
--- a/chrome/renderer/render_view.cc
+++ b/chrome/renderer/render_view.cc
@@ -3249,16 +3249,6 @@ void RenderView::OnFind(int request_id, const string16& search_text,
   }
 }
 
-std::string RenderView::DetectLanguage() {
-  if (!webview() || is_loading_)
-    return kUnknownLanguageCode;
-
-  WebFrame* main_frame = webview()->mainFrame();
-  std::wstring contents;
-  CaptureText(main_frame, &contents);
-  return DetermineTextLanguage(contents);
-}
-
 // static
 std::string RenderView::DetermineTextLanguage(const std::wstring& text) {
   std::string language = kUnknownLanguageCode;
diff --git a/chrome/renderer/render_view.h b/chrome/renderer/render_view.h
index 60deea6..691ce8a 100644
--- a/chrome/renderer/render_view.h
+++ b/chrome/renderer/render_view.h
@@ -452,12 +452,6 @@ class RenderView : public RenderWidget,
 
   PageTranslator* page_translator() const { return page_translator_.get(); }
 
-  // Returns the ISO 639 language code of the current page (e.g. en, fr).
-  // If ISO 639-1 code is not available for the language, ISO 639-2 3-letter
-  // code will be returned (e.g. fil for Filipino and und for undtermined). For
-  // traditional and simplified Chinse, 'zh-TW'  and 'zh-CN' will be returned.
-  std::string DetectLanguage();
-
 #if defined(OS_MACOSX)
   // Helper routines for GPU plugin support. Used by the
   // WebPluginDelegateProxy, which has a pointer to the RenderView.
diff --git a/chrome/renderer/translate/page_translator.cc b/chrome/renderer/translate/page_translator.cc
index e2c5692..22e24be 100644
--- a/chrome/renderer/translate/page_translator.cc
+++ b/chrome/renderer/translate/page_translator.cc
@@ -77,45 +77,42 @@ void PageTranslator::TranslatePage(int page_id,
     ResetPageStates();
     page_id_ = page_id;
     secure_page_ = static_cast<GURL>(main_frame->top()->url()).SchemeIsSecure();
-  }
-  if (original_language_.empty()) {
+
     original_language_ = source_lang;
-    current_language_ = source_lang;
-  }
+    current_language_ = target_lang;
 
-  if (original_language_ != current_language_) {
-    // The page has already been translated.
-    if (target_lang == current_language_) {
-      NOTREACHED();
-      return;
+    // Translate all frames contained within the main-frame.
+    for (WebKit::WebFrame* frame = main_frame;
+         frame; frame = frame->traverseNext(false)) {
+      TranslateFrame(frame);
     }
-    // Any pending translation is now useless.
-    ClearPendingTranslations();
-    // No need to parse again the DOM, we have all the text nodes and their
-    // original text in |text_nodes_| and |text_chunks_|.
-    std::vector<NodeList*>::iterator text_nodes_iter = text_nodes_.begin();
-    std::vector<TextChunks*>::iterator text_chunks_iter = text_chunks_.begin();
-    for (;text_nodes_iter != text_nodes_.end();
-         ++text_nodes_iter, ++text_chunks_iter) {
-      DCHECK(text_chunks_iter != text_chunks_.end());
-      int work_id =
-          text_translator_->Translate(**text_chunks_iter,
-                                      source_lang, target_lang,
-                                      secure_page_, this);
-      pending_translations_[work_id] = *text_nodes_iter;
-    }
-    current_language_ = target_lang;
     return;
   }
 
-  // We are about to start the translation process.
-  current_language_ = target_lang;
+  // The page has already been translated, the text nodes are already available.
+  DCHECK(!text_nodes_.empty());
 
-  // Translate all frames contained within the main-frame.
-  for (WebKit::WebFrame* frame = main_frame;
-       frame; frame = frame->traverseNext(false)) {
-    TranslateFrame(frame);
+  if (target_lang == original_language_) {
+    // Special case where we want to revert to the original language.
+    RevertTranslation();
+    return;
   }
+
+  // Any pending translation is now useless.
+  ClearPendingTranslations();
+  // No need to parse again the DOM, we have all the text nodes and their
+  // original text in |text_nodes_| and |text_chunks_|.
+  std::vector<NodeList*>::iterator text_nodes_iter = text_nodes_.begin();
+  std::vector<TextChunks*>::iterator text_chunks_iter = text_chunks_.begin();
+  for (;text_nodes_iter != text_nodes_.end();
+       ++text_nodes_iter, ++text_chunks_iter) {
+    DCHECK(text_chunks_iter != text_chunks_.end());
+    int work_id = text_translator_->Translate(**text_chunks_iter,
+                                              source_lang, target_lang,
+                                              secure_page_, this);
+    pending_translations_[work_id] = *text_nodes_iter;
+  }
+  current_language_ = target_lang;
 }
 
 void PageTranslator::TranslateFrame(WebKit::WebFrame* web_frame) {
@@ -301,3 +298,23 @@ void PageTranslator::ResetPageStates() {
 void PageTranslator::ClearPendingTranslations() {
   pending_translations_.clear();
 }
+
+void PageTranslator::RevertTranslation() {
+  ClearPendingTranslations();
+
+  DCHECK(!text_nodes_.empty());
+
+  std::vector<NodeList*>::iterator text_nodes_iter = text_nodes_.begin();
+  std::vector<TextChunks*>::iterator text_chunks_iter = text_chunks_.begin();
+  for (;text_nodes_iter != text_nodes_.end();
+       ++text_nodes_iter, ++text_chunks_iter) {
+    DCHECK(text_chunks_iter != text_chunks_.end());
+    DCHECK((*text_nodes_iter)->size() == (*text_chunks_iter)->size());
+    NodeList::iterator node_iter = (*text_nodes_iter)->begin();
+    TextChunks::const_iterator text_iter = (*text_chunks_iter)->begin();
+    for (; node_iter != (*text_nodes_iter)->end(); ++node_iter, ++text_iter) {
+      node_iter->setNodeValue(*text_iter);
+    }
+  }
+  current_language_ = original_language_;
+}
diff --git a/chrome/renderer/translate/page_translator.h b/chrome/renderer/translate/page_translator.h
index 1d8bbc7..2ec5401 100644
--- a/chrome/renderer/translate/page_translator.h
+++ b/chrome/renderer/translate/page_translator.h
@@ -110,6 +110,9 @@ class PageTranslator : public TextTranslator::Delegate {
   // request received after this call will be ignored.
   void ClearPendingTranslations();
 
+  // Reverts the text nodes in the page to their original text.
+  void RevertTranslation();
+
   // Our delegate (notified when a page is translated).
   PageTranslatorDelegate* delegate_;