// 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-CHROMIUM file.

#include "browser/media/media_capture_devices_dispatcher.h"

#include "base/logging.h"
#include "content/public/browser/browser_thread.h"
#include "content/public/browser/media_devices_monitor.h"
#include "content/public/common/desktop_media_id.h"
#include "content/public/common/media_stream_request.h"

namespace brightray {

using content::BrowserThread;
using content::MediaStreamDevices;

namespace {

// Finds a device in |devices| that has |device_id|, or NULL if not found.
const content::MediaStreamDevice* FindDeviceWithId(
    const content::MediaStreamDevices& devices,
    const std::string& device_id) {
  content::MediaStreamDevices::const_iterator iter = devices.begin();
  for (; iter != devices.end(); ++iter) {
    if (iter->id == device_id) {
      return &(*iter);
    }
  }
  return NULL;
};

}  // namespace

MediaCaptureDevicesDispatcher* MediaCaptureDevicesDispatcher::GetInstance() {
  return Singleton<MediaCaptureDevicesDispatcher>::get();
}

MediaCaptureDevicesDispatcher::MediaCaptureDevicesDispatcher()
    : devices_enumerated_(false),
      is_device_enumeration_disabled_(false) {
  // MediaCaptureDevicesDispatcher is a singleton. It should be created on
  // UI thread.
  DCHECK(BrowserThread::CurrentlyOn(BrowserThread::UI));
}

MediaCaptureDevicesDispatcher::~MediaCaptureDevicesDispatcher() {}

const MediaStreamDevices&
MediaCaptureDevicesDispatcher::GetAudioCaptureDevices() {
  DCHECK(BrowserThread::CurrentlyOn(BrowserThread::UI));
  if (!is_device_enumeration_disabled_ && !devices_enumerated_) {
    content::EnsureMonitorCaptureDevices();
    devices_enumerated_ = true;
  }
  return audio_devices_;
}

const MediaStreamDevices&
MediaCaptureDevicesDispatcher::GetVideoCaptureDevices() {
  DCHECK(BrowserThread::CurrentlyOn(BrowserThread::UI));
  if (!is_device_enumeration_disabled_ && !devices_enumerated_) {
    content::EnsureMonitorCaptureDevices();
    devices_enumerated_ = true;
  }
  return video_devices_;
}

void MediaCaptureDevicesDispatcher::GetDefaultDevices(
    bool audio,
    bool video,
    content::MediaStreamDevices* devices) {
  DCHECK(BrowserThread::CurrentlyOn(BrowserThread::UI));
  DCHECK(audio || video);

  if (audio) {
    const content::MediaStreamDevice* device = GetFirstAvailableAudioDevice();
    if (device)
      devices->push_back(*device);
  }

  if (video) {
    const content::MediaStreamDevice* device = GetFirstAvailableVideoDevice();
    if (device)
      devices->push_back(*device);
  }
}

const content::MediaStreamDevice*
MediaCaptureDevicesDispatcher::GetRequestedAudioDevice(
    const std::string& requested_audio_device_id) {
  DCHECK(BrowserThread::CurrentlyOn(BrowserThread::UI));
  const content::MediaStreamDevices& audio_devices = GetAudioCaptureDevices();
  const content::MediaStreamDevice* const device =
      FindDeviceWithId(audio_devices, requested_audio_device_id);
  return device;
}

const content::MediaStreamDevice*
MediaCaptureDevicesDispatcher::GetFirstAvailableAudioDevice() {
  DCHECK(BrowserThread::CurrentlyOn(BrowserThread::UI));
  const content::MediaStreamDevices& audio_devices = GetAudioCaptureDevices();
  if (audio_devices.empty())
    return NULL;
  return &(*audio_devices.begin());
}

const content::MediaStreamDevice*
MediaCaptureDevicesDispatcher::GetRequestedVideoDevice(
    const std::string& requested_video_device_id) {
  DCHECK(BrowserThread::CurrentlyOn(BrowserThread::UI));
  const content::MediaStreamDevices& video_devices = GetVideoCaptureDevices();
  const content::MediaStreamDevice* const device =
      FindDeviceWithId(video_devices, requested_video_device_id);
  return device;
}

const content::MediaStreamDevice*
MediaCaptureDevicesDispatcher::GetFirstAvailableVideoDevice() {
  DCHECK(BrowserThread::CurrentlyOn(BrowserThread::UI));
  const content::MediaStreamDevices& video_devices = GetVideoCaptureDevices();
  if (video_devices.empty())
    return NULL;
  return &(*video_devices.begin());
}

void MediaCaptureDevicesDispatcher::DisableDeviceEnumerationForTesting() {
  is_device_enumeration_disabled_ = true;
}

void MediaCaptureDevicesDispatcher::OnAudioCaptureDevicesChanged(
    const content::MediaStreamDevices& devices) {
  DCHECK(BrowserThread::CurrentlyOn(BrowserThread::IO));
  BrowserThread::PostTask(
      BrowserThread::UI, FROM_HERE,
      base::Bind(&MediaCaptureDevicesDispatcher::UpdateAudioDevicesOnUIThread,
                 base::Unretained(this), devices));
}

void MediaCaptureDevicesDispatcher::OnVideoCaptureDevicesChanged(
    const content::MediaStreamDevices& devices) {
  DCHECK(BrowserThread::CurrentlyOn(BrowserThread::IO));
  BrowserThread::PostTask(
      BrowserThread::UI, FROM_HERE,
      base::Bind(&MediaCaptureDevicesDispatcher::UpdateVideoDevicesOnUIThread,
                 base::Unretained(this), devices));
}

void MediaCaptureDevicesDispatcher::OnMediaRequestStateChanged(
    int render_process_id,
    int render_view_id,
    int page_request_id,
    const content::MediaStreamDevice& device,
    content::MediaRequestState state) {
  DCHECK(BrowserThread::CurrentlyOn(BrowserThread::IO));

}

void MediaCaptureDevicesDispatcher::OnAudioStreamPlayingChanged(
    int render_process_id, int render_view_id, int stream_id,
    bool is_playing, float power_dbfs, bool clipped) {
}

void MediaCaptureDevicesDispatcher::OnCreatingAudioStream(
    int render_process_id,
    int render_view_id) {
  DCHECK(BrowserThread::CurrentlyOn(BrowserThread::IO));
}

void MediaCaptureDevicesDispatcher::UpdateAudioDevicesOnUIThread(
    const content::MediaStreamDevices& devices) {
  DCHECK(BrowserThread::CurrentlyOn(BrowserThread::UI));
  devices_enumerated_ = true;
  audio_devices_ = devices;
}

void MediaCaptureDevicesDispatcher::UpdateVideoDevicesOnUIThread(
    const content::MediaStreamDevices& devices){
  DCHECK(BrowserThread::CurrentlyOn(BrowserThread::UI));
  devices_enumerated_ = true;
  video_devices_ = devices;
}

}  // namespace brightray