MD History: Rewrite i18n system using ReplaceTemplateExpressions

chrome/browser/ui/webui/md_history_ui.cc

 // Copyright 2015 The Chromium Authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 #include "chrome/browser/ui/webui/md_history_ui.h"
 
 #include "build/build_config.h"
+#include "chrome/browser/browser_process.h"
 #include "chrome/browser/profiles/profile.h"
 #include "chrome/browser/ui/webui/browsing_history_handler.h"
 #include "chrome/browser/ui/webui/metrics_handler.h"
 #include "chrome/common/url_constants.h"
 #include "components/search/search.h"
 #include "content/public/browser/web_ui.h"
 #include "content/public/browser/web_ui_data_source.h"
 #include "grit/browser_resources.h"
 #include "grit/components_scaled_resources.h"
 #include "grit/components_strings.h"
 #include "grit/generated_resources.h"
 #include "grit/theme_resources.h"
+#include "ui/base/l10n/l10n_util.h"
 #include "ui/base/resource/resource_bundle.h"
+#include "ui/base/template_expressions.h"
+#include "ui/base/webui/web_ui_util.h"
 
 #if !defined(OS_ANDROID)
 #include "chrome/browser/ui/webui/foreign_session_handler.h"
 #include "chrome/browser/ui/webui/history_login_handler.h"
 #endif
 
 namespace {
 
+bool HandleDataRequest(
+    const std::string& path,
+    const content::WebUIDataSource::GotDataCallback& callback) {
+  std::map<const std::string, std::string> substitutions;
+  // Localized strings (alphabetical order).
+  substitutions["clearSearch"] =
+      l10n_util::GetStringUTF8(IDS_MD_HISTORY_CLEAR_SEARCH);
+  substitutions["language"] =
+      l10n_util::GetLanguage(g_browser_process->GetApplicationLocale());
+  substitutions["moreFromSite"] =
+      l10n_util::GetStringUTF8(IDS_HISTORY_MORE_FROM_SITE);
+  substitutions["removeFromHistory"] =
+      l10n_util::GetStringUTF8(IDS_HISTORY_REMOVE_PAGE);
+  substitutions["search"] = l10n_util::GetStringUTF8(IDS_MD_HISTORY_SEARCH);
+  substitutions["title"] = l10n_util::GetStringUTF8(IDS_HISTORY_TITLE);
+  substitutions["textdirection"] = webui::GetTextDirection();
+
+  std::map<std::string, int> router;

[calamity, 2016/02/01 23:45:33]

Can we make this a const static local?

[tsergeant, 2016/02/02 01:33:10]

Yes, we can.

+  // Localized resources (alphabetical order).
+  router[""] = IDR_MD_HISTORY_HISTORY_HTML;
+  router["history_card.html"] = IDR_MD_HISTORY_HISTORY_CARD_HTML;
+  router["history_card_manager.html"] =
+      IDR_MD_HISTORY_HISTORY_CARD_MANAGER_HTML;
+  router["history_item.html"] = IDR_MD_HISTORY_HISTORY_ITEM_HTML;
+  router["history_toolbar.html"] = IDR_MD_HISTORY_HISTORY_TOOLBAR_HTML;
+
+  auto path_resource = router.find(path);
+  if (path_resource != router.end()) {
+    base::StringPiece resource_full_text(
+        ResourceBundle::GetSharedInstance().GetRawDataResource(
+            (*path_resource).second));
+
+    std::string localized_text =
+        ui::ReplaceTemplateExpressions(resource_full_text, substitutions);
+    callback.Run(base::RefCountedString::TakeString(&localized_text));
+
+    return true;
+  }
+
+  return false;
+}
+
 content::WebUIDataSource* CreateMdHistoryUIHTMLSource() {
   content::WebUIDataSource* source =
       content::WebUIDataSource::Create(chrome::kChromeUIHistoryHost);
 
-  // Localized strings (alphabetical order).
-  source->AddLocalizedString("clearSearch", IDS_MD_HISTORY_CLEAR_SEARCH);
-  source->AddLocalizedString("moreFromSite", IDS_HISTORY_MORE_FROM_SITE);
-  source->AddLocalizedString("removeFromHistory", IDS_HISTORY_REMOVE_PAGE);
-  source->AddLocalizedString("search", IDS_MD_HISTORY_SEARCH);
-  source->AddLocalizedString("title", IDS_HISTORY_TITLE);
-
-  source->AddResourcePath("history_card.html",
-                          IDR_MD_HISTORY_HISTORY_CARD_HTML);
+  // Resources which do not need localization.
   source->AddResourcePath("history_card.js", IDR_MD_HISTORY_HISTORY_CARD_JS);
-  source->AddResourcePath("history_card_manager.html",
-                          IDR_MD_HISTORY_HISTORY_CARD_MANAGER_HTML);
   source->AddResourcePath("history_card_manager.js",
                           IDR_MD_HISTORY_HISTORY_CARD_MANAGER_JS);
-  source->AddResourcePath("history_item.html",
-                          IDR_MD_HISTORY_HISTORY_ITEM_HTML);
   source->AddResourcePath("history_item.js", IDR_MD_HISTORY_HISTORY_ITEM_JS);
-  source->AddResourcePath("history_toolbar.html",
-                          IDR_MD_HISTORY_HISTORY_TOOLBAR_HTML);
   source->AddResourcePath("history_toolbar.js",
                           IDR_MD_HISTORY_HISTORY_TOOLBAR_JS);
   source->AddResourcePath("history.js", IDR_MD_HISTORY_HISTORY_JS);
 
-  source->SetDefaultResource(IDR_MD_HISTORY_HISTORY_HTML);
   source->SetJsonPath("strings.js");
-
+  source->SetRequestFilter(base::Bind(&HandleDataRequest));
   return source;
 }
 
 }  // namespace
 
 MdHistoryUI::MdHistoryUI(content::WebUI* web_ui) : WebUIController(web_ui) {
   web_ui->AddMessageHandler(new BrowsingHistoryHandler());
   web_ui->AddMessageHandler(new MetricsHandler());
 
   // On mobile we deal with foreign sessions differently.
 #if !defined(OS_ANDROID)
   if (search::IsInstantExtendedAPIEnabled()) {
     web_ui->AddMessageHandler(new browser_sync::ForeignSessionHandler());
     web_ui->AddMessageHandler(new HistoryLoginHandler());
   }
 #endif
 
   Profile* profile = Profile::FromWebUI(web_ui);
   content::WebUIDataSource::Add(profile, CreateMdHistoryUIHTMLSource());
 }
 
 MdHistoryUI::~MdHistoryUI() {}
 
 base::RefCountedMemory* MdHistoryUI::GetFaviconResourceBytes(
     ui::ScaleFactor scale_factor) {
   return ResourceBundle::GetSharedInstance().LoadDataResourceBytesForScale(
       IDR_HISTORY_FAVICON, scale_factor);
 }