1 /*
2  * Copyright 2018 The Android Open Source Project
3  *
4  * Licensed under the Apache License, Version 2.0 (the "License");
5  * you may not use this file except in compliance with the License.
6  * You may obtain a copy of the License at
7  *
8  *      http://www.apache.org/licenses/LICENSE-2.0
9  *
10  * Unless required by applicable law or agreed to in writing, software
11  * distributed under the License is distributed on an "AS IS" BASIS,
12  * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
13  * See the License for the specific language governing permissions and
14  * limitations under the License.
15  */
16 
17 #pragma once
18 
19 #include <set>
20 #include <string>
21 
22 #include <base/callback_forward.h>
23 
24 #include "avrcp_common.h"
25 #include "raw_address.h"
26 
27 namespace bluetooth {
28 namespace avrcp {
29 
30 struct SongInfo {
31   std::string media_id;  // This gets converted to a UID in the native service
32   std::set<AttributeEntry> attributes;
33 };
34 
35 enum PlayState : uint8_t {
36   STOPPED = 0x00,
37   PLAYING,
38   PAUSED,
39   FWD_SEEK,
40   REV_SEEK,
41   ERROR = 0xFF,
42 };
43 
44 struct PlayStatus {
45   uint32_t position;
46   uint32_t duration;
47   PlayState state;
48 };
49 
50 struct MediaPlayerInfo {
51   uint16_t id;
52   std::string name;
53   bool browsing_supported;
54 };
55 
56 struct FolderInfo {
57   std::string media_id;
58   bool is_playable;
59   std::string name;
60 };
61 
62 // TODO (apanicke): Convert this to a union
63 struct ListItem {
64   enum : uint8_t {
65     FOLDER,
66     SONG,
67   } type;
68 
69   FolderInfo folder;
70   SongInfo song;
71 };
72 
73 class MediaCallbacks {
74  public:
75   virtual void SendMediaUpdate(bool track_changed, bool play_state,
76                                bool queue) = 0;
77   virtual void SendFolderUpdate(bool available_players, bool addressed_players,
78                                 bool uids_changed) = 0;
79   virtual void SendActiveDeviceChanged(const RawAddress& address) = 0;
80   virtual ~MediaCallbacks() = default;
81 };
82 
83 // The classes below are used by the JNI and are loaded dynamically with the
84 // Bluetooth library. All classes must be pure virtual otherwise a compiler
85 // error occurs when trying to link the function implementation.
86 
87 // MediaInterface defines the class that the AVRCP Service uses in order
88 // communicate with the media layer. The media layer will define its own
89 // implementation of this object and register it with the service using
90 // Avrcp::ServiceInterface::Init(). At this point the AVRCP Service will
91 // call RegisterUpdateCallbacks() to provide an handle to use to send
92 // notifications about changes in the Media Interface.
93 //
94 // NOTES: The current implementation has the native service handle all the
95 // thread switching. It will call the interface functions on the btif/jni
96 // thread and the callback will post its results to the bta thread.
97 // In the future the interface the JNI registered with the
98 // service should post all its tasks to the JNI thread itself so that the native
99 // service isn't aware of the thread the interface functions need to be called
100 // on. It can then supply callbacks that post results to the correct thread
101 // allowing the threading model to be totally encapsulated and allow correct
102 // behavior in case the threading model changes on either side.
103 class MediaInterface {
104  public:
105   virtual void SendKeyEvent(uint8_t key, KeyState state) = 0;
106 
107   using SongInfoCallback = base::Callback<void(SongInfo)>;
108   virtual void GetSongInfo(SongInfoCallback info_cb) = 0;
109 
110   using PlayStatusCallback = base::Callback<void(PlayStatus)>;
111   virtual void GetPlayStatus(PlayStatusCallback status_cb) = 0;
112 
113   // Contains the current queue and the media ID of the currently playing item
114   // in the queue
115   using NowPlayingCallback =
116       base::Callback<void(std::string, std::vector<SongInfo>)>;
117   virtual void GetNowPlayingList(NowPlayingCallback now_playing_cb) = 0;
118 
119   // TODO (apanicke): Use a map with the ID as the key instead of vector
120   // in follow up cleanup patches. This allows simplification of the
121   // MediaPlayerInfo object
122   using MediaListCallback =
123       base::Callback<void(uint16_t curr_player, std::vector<MediaPlayerInfo>)>;
124   virtual void GetMediaPlayerList(MediaListCallback list_cb) = 0;
125 
126   using FolderItemsCallback = base::Callback<void(std::vector<ListItem>)>;
127   virtual void GetFolderItems(uint16_t player_id, std::string media_id,
128                               FolderItemsCallback folder_cb) = 0;
129 
130   using SetBrowsedPlayerCallback = base::Callback<void(
131       bool success, std::string root_id, uint32_t num_items)>;
132   virtual void SetBrowsedPlayer(uint16_t player_id,
133                                 SetBrowsedPlayerCallback browse_cb) = 0;
134 
135   virtual void PlayItem(uint16_t player_id, bool now_playing,
136                         std::string media_id) = 0;
137 
138   virtual void SetActiveDevice(const RawAddress& address) = 0;
139 
140   virtual void RegisterUpdateCallback(MediaCallbacks* callback) = 0;
141 
142   virtual void UnregisterUpdateCallback(MediaCallbacks* callback) = 0;
143 
144   MediaInterface() = default;
145   virtual ~MediaInterface() = default;
146 };
147 
148 class VolumeInterface {
149  public:
150   // TODO (apanicke): Investigate the best value type for volume. Right now it
151   // is a value from 0-127 because thats what AVRCP uses.
152   using VolumeChangedCb = base::Callback<void(int8_t volume)>;
153 
154   // Indicate that a device has been connected that does not support absolute
155   // volume.
156   virtual void DeviceConnected(const RawAddress& bdaddr) = 0;
157 
158   // Indicate that a device has been connected that does support absolute
159   // volume. The callback will be immediately called with the current volume
160   // which will be sent to the device.
161   virtual void DeviceConnected(const RawAddress& bdaddr,
162                                VolumeChangedCb cb) = 0;
163 
164   // Indicate that a device has been disconnected from AVRCP. Will unregister
165   // any callbacks if absolute volume is supported.
166   virtual void DeviceDisconnected(const RawAddress& bdaddr) = 0;
167 
168   virtual void SetVolume(int8_t volume) = 0;
169 
170   virtual ~VolumeInterface() = default;
171 };
172 
173 class ServiceInterface {
174  public:
175   // mediaInterface can not be null. If volumeInterface is null then Absolute
176   // Volume is disabled.
177   virtual void Init(MediaInterface* mediaInterface,
178                     VolumeInterface* volumeInterface) = 0;
179   virtual bool ConnectDevice(const RawAddress& bdaddr) = 0;
180   virtual bool DisconnectDevice(const RawAddress& bdaddr) = 0;
181   virtual bool Cleanup() = 0;
182 
183  protected:
184   virtual ~ServiceInterface() = default;
185 };
186 
187 }  // namespace avrcp
188 }  // namespace bluetooth