Implement an observer interface for the site engagement service.

chrome/browser/engagement/site_engagement_service.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/engagement/site_engagement_service.h"
 
 #include <stddef.h>
 
 #include <algorithm>
 #include <utility>
@@ skipping 191 matching lines @@
       return score >= SiteEngagementScore::GetMediumEngagementBoundary();
     case ENGAGEMENT_LEVEL_HIGH:
       return score >= SiteEngagementScore::GetHighEngagementBoundary();
     case ENGAGEMENT_LEVEL_MAX:
       return score == SiteEngagementScore::kMaxPoints;
   }
   NOTREACHED();
   return false;
 }
 
+void SiteEngagementService::AddObserver(SiteEngagementObserver* observer) {
+  observer_list_.AddObserver(observer);
+}
+
+void SiteEngagementService::RemoveObserver(SiteEngagementObserver* observer) {
+  observer_list_.RemoveObserver(observer);
+}
+
 void SiteEngagementService::ResetScoreForURL(const GURL& url, double score) {
   ResetScoreAndAccessTimesForURL(url, score, nullptr);
 }
 
 void SiteEngagementService::SetLastShortcutLaunchTime(const GURL& url) {
   HostContentSettingsMap* settings_map =
     HostContentSettingsMapFactory::GetForProfile(profile_);
   std::unique_ptr<base::DictionaryValue> score_dict =
       GetScoreDictForOrigin(settings_map, url);
   SiteEngagementScore score(clock_.get(), *score_dict);
@@ skipping 53 matching lines @@
   std::unique_ptr<base::DictionaryValue> score_dict =
       GetScoreDictForOrigin(settings_map, url);
   SiteEngagementScore score(clock_.get(), *score_dict);
 
   score.AddPoints(points);
   if (score.UpdateScoreDict(score_dict.get())) {
     settings_map->SetWebsiteSettingDefaultScope(
         url, GURL(), CONTENT_SETTINGS_TYPE_SITE_ENGAGEMENT, std::string(),
         score_dict.release());
   }
+  FOR_EACH_OBSERVER(SiteEngagementObserver, observer_list_,
+                    OnEngagementIncreased(this, url, score.GetScore()));
 }
 
 void SiteEngagementService::AfterStartupTask() {
   CleanupEngagementScores();
   RecordMetrics();
 }
 
 void SiteEngagementService::CleanupEngagementScores() {
   HostContentSettingsMap* settings_map =
     HostContentSettingsMapFactory::GetForProfile(profile_);
@@ skipping 63 matching lines @@
   // if there are an odd number of scores, or the average of the two middle
   // scores otherwise.
   std::sort(scores.begin(), scores.end());
   size_t mid = scores.size() / 2;
   if (scores.size() % 2 == 1)
     return scores[mid];
   else
     return (scores[mid - 1] + scores[mid]) / 2;
 }
 
+double SiteEngagementService::GetScoreForEngagementLevel(
+    EngagementLevel level) const {
+  switch (level) {
+    case ENGAGEMENT_LEVEL_NONE:
+      return 0;
+    case ENGAGEMENT_LEVEL_LOW:
+      return SiteEngagementScore::GetMinimumEngagementIncrement();
+    case ENGAGEMENT_LEVEL_MEDIUM:
+      return SiteEngagementScore::GetMediumEngagementBoundary();
+    case ENGAGEMENT_LEVEL_HIGH:
+      return SiteEngagementScore::GetHighEngagementBoundary();
+    case ENGAGEMENT_LEVEL_MAX:
+      return SiteEngagementScore::kMaxPoints;
+    default:
+      NOTREACHED();
+      return 0;
+  }
+}
+
 void SiteEngagementService::HandleMediaPlaying(const GURL& url,
                                                bool is_hidden) {
   SiteEngagementMetrics::RecordEngagement(
       is_hidden ? SiteEngagementMetrics::ENGAGEMENT_MEDIA_HIDDEN
                 : SiteEngagementMetrics::ENGAGEMENT_MEDIA_VISIBLE);
   AddPoints(url, is_hidden ? SiteEngagementScore::GetHiddenMediaPoints()
                            : SiteEngagementScore::GetVisibleMediaPoints());
   RecordMetrics();
 }
 
@@ skipping 144 matching lines @@
         nullptr);
     return;
   }
 
   if (engagement_score.UpdateScoreDict(score_dict.get())) {
     settings_map->SetWebsiteSettingDefaultScope(
         url, GURL(), CONTENT_SETTINGS_TYPE_SITE_ENGAGEMENT, std::string(),
         score_dict.release());
   }
 }