First version of the time slicing on the urls. Not ready for review yet.

chrome/browser/ui/webui/ntp/suggestions_page_handler.cc

+// Copyright (c) 2012 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/ntp/suggestions_page_handler.h"
+
+#include <set>
+
+#include "base/bind.h"
+#include "base/bind_helpers.h"
+#include "base/md5.h"
+#include "base/memory/scoped_vector.h"
+#include "base/memory/singleton.h"
+#include "base/string16.h"
+#include "base/string_number_conversions.h"
+#include "base/threading/thread.h"
+#include "base/utf_string_conversions.h"
+#include "base/values.h"
+#include "chrome/browser/history/page_usage_data.h"
+#include "chrome/browser/history/time_filter.h"
+#include "chrome/browser/history/top_sites.h"
+#include "chrome/browser/profiles/profile.h"
+#include "chrome/browser/ui/webui/chrome_url_data_manager.h"
+#include "chrome/browser/ui/webui/favicon_source.h"
+#include "chrome/browser/ui/webui/ntp/new_tab_ui.h"
+#include "chrome/browser/ui/webui/ntp/thumbnail_source.h"
+#include "chrome/common/chrome_notification_types.h"
+#include "chrome/common/url_constants.h"
+#include "content/public/browser/browser_thread.h"
+#include "content/public/browser/notification_source.h"
+#include "content/public/browser/user_metrics.h"
+#include "content/public/browser/web_ui.h"
+#include "googleurl/src/gurl.h"
+
+using content::UserMetricsAction;
+
+SuggestionsHandler::SuggestionsHandler()
+    : got_first_suggestions_request_(false) {
+}
+
+SuggestionsHandler::~SuggestionsHandler() {
+}
+
+void SuggestionsHandler::RegisterMessages() {
+  Profile* profile = Profile::FromWebUI(web_ui());
+  // Set up our sources for thumbnail and favicon data.
+  profile->GetChromeURLDataManager()->AddDataSource(
+      new ThumbnailSource(profile));
+  profile->GetChromeURLDataManager()->AddDataSource(
+      new FaviconSource(profile, FaviconSource::FAVICON));
+
+  // TODO(georgey) change the source of the web-sites to provide our data.
+  // Initial commit uses top sites as a data source.
+  history::TopSites* top_sites = profile->GetTopSites();
+  if (top_sites) {
+    // TopSites updates itself after a delay. This is especially noticable when
+    // your profile is empty. Ask TopSites to update itself when we're about to
+    // show the new tab page.
+    top_sites->SyncWithHistory();
+
+    // Register for notification when TopSites changes so that we can update
+    // ourself.
+    registrar_.Add(this, chrome::NOTIFICATION_TOP_SITES_CHANGED,
+                   content::Source<history::TopSites>(top_sites));
+  }
+
+  // We pre-emptively make a fetch for the available pages so we have the
+  // results sooner.
+  StartQueryForSuggestions();
+
+  web_ui()->RegisterMessageCallback("getSuggestions",
+      base::Bind(&SuggestionsHandler::HandleGetSuggestions,
+                 base::Unretained(this)));
+  // Register ourselves for any suggestions item blacklisting.
+  web_ui()->RegisterMessageCallback("blacklistURLFromSuggestions",
+      base::Bind(&SuggestionsHandler::HandleBlacklistURL,
+                 base::Unretained(this)));
+  web_ui()->RegisterMessageCallback("removeURLsFromSuggestionsBlacklist",
+      base::Bind(&SuggestionsHandler::HandleRemoveURLsFromBlacklist,
+                 base::Unretained(this)));
+  web_ui()->RegisterMessageCallback("clearSuggestionsURLsBlacklist",
+      base::Bind(&SuggestionsHandler::HandleClearBlacklist,
+                 base::Unretained(this)));
+}
+
+void SuggestionsHandler::HandleGetSuggestions(const ListValue* args) {
+  if (!got_first_suggestions_request_) {
+    // If our initial data is already here, return it.
+    SendPagesValue();
+    got_first_suggestions_request_ = true;
+  } else {
+    StartQueryForSuggestions();
+  }
+}
+
+void SuggestionsHandler::SendPagesValue() {
+  if (pages_value_.get()) {
+    // TODO(georgey) add actual blacklist.
+    bool has_blacklisted_urls = false;
+    base::FundamentalValue has_blacklisted_urls_value(has_blacklisted_urls);
+    web_ui()->CallJavascriptFunction("ntp.setSuggestionsPages",
+                                     *(pages_value_.get()),
+                                     has_blacklisted_urls_value);
+    pages_value_.reset();
+  }
+}
+
+void SuggestionsHandler::StartQueryForSuggestions() {
+  HistoryService* history =
+      Profile::FromWebUI(web_ui())->GetHistoryService(Profile::EXPLICIT_ACCESS);
+  // |history| may be null during unit tests.
+  if (history) {
+    history::TimeFilter time_filter;
+    base::TimeDelta half_an_hour =
+       base::TimeDelta::FromMicroseconds(base::Time::kMicrosecondsPerHour / 2);
+    base::Time now = base::Time::Now();
+    time_filter.SetTimeInRangeFilter(now - half_an_hour, now + half_an_hour);
+    history->QueryMostVisitedURLsDuringTime(
+        0, time_filter, &history_consumer_,
+        base::Bind(&SuggestionsHandler::OnSuggestionsURLsAvailable,
+                   base::Unretained(this)));
+  }
+}
+
+void SuggestionsHandler::HandleBlacklistURL(const ListValue* args) {
+  std::string url = UTF16ToUTF8(ExtractStringValue(args));
+  BlacklistURL(GURL(url));
+}
+
+void SuggestionsHandler::HandleRemoveURLsFromBlacklist(const ListValue* args) {
+  DCHECK_GT(args->GetSize(), 0U);
+  // TODO(georgey) remove URLs from blacklist.
+}
+
+void SuggestionsHandler::HandleClearBlacklist(const ListValue* args) {
+  // TODO(georgey) clear blacklist.
+}
+
+void SuggestionsHandler::SetPagesValueFromTopSites(
+    const history::MostVisitedURLList& data) {
+  pages_value_.reset(new ListValue());
+  for (size_t i = 0; i < data.size(); i++) {
+    const history::MostVisitedURL& suggested_url = data[i];
+    DictionaryValue* page_value = new DictionaryValue();
+    if (suggested_url.url.is_empty()) {
+      continue;
+    }
+
+    NewTabUI::SetURLTitleAndDirection(page_value,
+                                      suggested_url.title,
+                                      suggested_url.url);
+    pages_value_->Append(page_value);
+  }
+}
+
+void SuggestionsHandler::OnSuggestionsURLsAvailable(
+    CancelableRequestProvider::Handle handle,
+    history::MostVisitedURLList data) {
+  SetPagesValueFromTopSites(data);
+  if (got_first_suggestions_request_)
+    SendPagesValue();
+}
+
+void SuggestionsHandler::Observe(int type,
+                                 const content::NotificationSource& source,
+                                 const content::NotificationDetails& details) {
+  DCHECK_EQ(type, chrome::NOTIFICATION_TOP_SITES_CHANGED);
+
+  // Suggestions urls changed, query again.
+  StartQueryForSuggestions();
+}
+
+void SuggestionsHandler::BlacklistURL(const GURL& url) {
+  // TODO(georgey) blacklist an URL.
+}
+
+std::string SuggestionsHandler::GetDictionaryKeyForURL(const std::string& url) {
+  return base::MD5String(url);
+}
+
+// static
+void SuggestionsHandler::RegisterUserPrefs(PrefService* prefs) {
+  // TODO(georgey) add user preferences (such as own blacklist) as needed.
+}