| // Copyright 2016 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. |
| |
| #ifndef CONTENT_BROWSER_MEDIA_AUDIBLE_METRICS_H_ |
| #define CONTENT_BROWSER_MEDIA_AUDIBLE_METRICS_H_ |
| |
| #include <list> |
| #include <memory> |
| #include <set> |
| |
| #include "base/time/tick_clock.h" |
| #include "content/common/content_export.h" |
| |
| namespace content { |
| |
| class WebContents; |
| |
| // This class handles metrics regarding audible WebContents. |
| // It records four different histograms: |
| // - how many WebContents are audible when a WebContents become audible. |
| // - how long multiple WebContents are audible at the same time. |
| // - for a browsing session, how often and how many WebContents get audible at |
| // the same time. |
| // - if an audible tab was closed and we only have one audible tab open anymore |
| // then we should record whether we closed the newest or oldest tab. |
| class CONTENT_EXPORT AudibleMetrics { |
| public: |
| // This is used for recording whether the audible tab that exited concurrent |
| // playback was the most recent. It is used for recording a histogram so |
| // values should not be changed. |
| enum class ExitConcurrentPlaybackContents { |
| kMostRecent = 0, |
| kOlder = 1, |
| kMaxValue = kOlder, |
| }; |
| |
| AudibleMetrics(); |
| ~AudibleMetrics(); |
| |
| void UpdateAudibleWebContentsState(const WebContents* web_contents, |
| bool audible); |
| void WebContentsDestroyed(const WebContents* web_contents, |
| bool recently_audible); |
| |
| void SetClockForTest(const base::TickClock* test_clock); |
| |
| int GetAudibleWebContentsSizeForTest() const { |
| return audible_web_contents_.size(); |
| } |
| |
| private: |
| void AddAudibleWebContents(const WebContents* web_contents); |
| void RemoveAudibleWebContents(const WebContents* web_contents); |
| |
| base::TimeTicks concurrent_web_contents_start_time_; |
| size_t max_concurrent_audible_web_contents_in_session_; |
| const base::TickClock* clock_; |
| |
| // This stores the audible web contents in insertion order. We add a |
| // web contents to the list when it becomes audible and remove it is |
| // destroyed. |
| std::list<const WebContents*> last_audible_web_contents_; |
| |
| // Stores all the web contents that are currently audible. We add a web |
| // contents to the set when it becomes currently audible and remove it when it |
| // is no longer audible. |
| std::set<const WebContents*> audible_web_contents_; |
| |
| DISALLOW_COPY_AND_ASSIGN(AudibleMetrics); |
| }; |
| |
| } // namespace content |
| |
| #endif // CONTENT_BROWSER_MEDIA_AUDIBLE_METRICS_H_ |