1 /*
2  * Copyright (c) 2021-2021 Huawei Device Co., Ltd.
3  * Licensed under the Apache License, Version 2.0 (the "License");
4  * you may not use this file except in compliance with the License.
5  * You may obtain a copy of the License at
6  *
7  *     http://www.apache.org/licenses/LICENSE-2.0
8  *
9  * Unless required by applicable law or agreed to in writing, software
10  * distributed under the License is distributed on an "AS IS" BASIS,
11  * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
12  * See the License for the specific language governing permissions and
13  * limitations under the License.
14  */
15 
16 #ifndef HISTREAMER_HIPLAYER_STATE_MACHINE_H
17 #define HISTREAMER_HIPLAYER_STATE_MACHINE_H
18 
19 #include <map>
20 #include <memory>
21 #include <queue>
22 #include <tuple>
23 #include "foundation/log.h"
24 #include "foundation/osal/base/synchronizer.h"
25 #include "foundation/osal/thread/mutex.h"
26 #include "foundation/osal/thread/task.h"
27 #include "foundation/utils/blocking_queue.h"
28 #include "pipeline/core/error_code.h"
29 #include "play_executor.h"
30 #include "plugin/common/any.h"
31 #include "state.h"
32 
33 namespace OHOS {
34 namespace Media {
35 class StateChangeCallback {
36 public:
37     virtual ~StateChangeCallback() = default;
38     virtual void OnStateChanged(StateId state) = 0;
39 };
40 
41 class StateMachine final : public OSAL::Task {
42 public:
43     explicit StateMachine(PlayExecutor& executor);
44 
45     ~StateMachine() override = default;
46 
47     void Stop() override;
48 
49     void SetStateCallback(StateChangeCallback* callback);
50 
51     const std::string& GetCurrentState() const;
52 
53     StateId GetCurrentStateId() const;
54 
55     ErrorCode SendEvent(Intent intent, const Plugin::Any& param = {});
56 
57     ErrorCode SendEvent(Intent intent, const Plugin::Any& param = {}) const;
58 
59     ErrorCode SendEventAsync(Intent intent, const Plugin::Any& param = {});
60 
61     ErrorCode SendEventAsync(Intent intent, const Plugin::Any& param = {}) const;
62 
63     void Notify(Intent intent, ErrorCode code);
64 
65 private:
66     using Job = std::function<Action()>;
67 
68     Action ProcessIntent(Intent intent, const Plugin::Any& param);
69 
70     void DoTask() override;
71 
72     void AddState(const std::shared_ptr<State>& state);
73 
74     ErrorCode ProcAction(Action nextAction);
75 
76     ErrorCode TransitionTo(const std::shared_ptr<State>& state);
77 
78     void OnIntentExecuted(Intent intent, Action action, ErrorCode result);
79 
80     mutable OSAL::Mutex mutex_ {};
81     mutable OSAL::Synchronizer<Intent, ErrorCode> intentSync_;
82     mutable std::shared_ptr<State> curState_ {nullptr};
83     mutable Intent lastIntent {Intent::INTENT_BUTT};
84     std::map<StateId, std::shared_ptr<State>> states_ {};
85     Media::BlockingQueue<Job> jobs_;
86     std::queue<Job> pendingJobs_ {};
87     StateChangeCallback* callback_ {nullptr};
88 };
89 } // namespace Media
90 } // namespace OHOS
91 #endif
92