1 /*
2  * Copyright (c) 2024-2024 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 LISTENER_BASE_H_
17 #define LISTENER_BASE_H_
18 
19 #include <list>
20 #include <memory>
21 #include <mutex>
22 #include <unordered_map>
23 
24 #include "camera_napi_auto_ref.h"
25 #include "camera_napi_utils.h"
26 namespace OHOS {
27 namespace CameraStandard {
28 class ListenerBase {
29 public:
30     explicit ListenerBase(napi_env env);
31     virtual ~ListenerBase();
32 
33     struct ExecuteCallbackNapiPara {
34         napi_value recv;
35         size_t argc;
36         const napi_value* argv;
37         napi_value* result;
38     };
39     virtual void SaveCallbackReference(const std::string eventName, napi_value callback, bool isOnce) final;
40     virtual void ExecuteCallback(const std::string eventName, const ExecuteCallbackNapiPara& callbackPara) const final;
41     virtual void RemoveCallbackRef(const std::string eventName, napi_value callback) final;
42     virtual void RemoveAllCallbacks(const std::string eventName) final;
43     virtual bool IsEmpty(const std::string eventName) const final;
44 
45 protected:
46     napi_env env_ = nullptr;
47 
48 private:
49     struct CallbackList {
50         std::mutex listMutex;
51         std::list<AutoRef> refList;
52     };
53 
GetCallbackList(const std::string eventName)54     inline CallbackList& GetCallbackList(const std::string eventName) const
55     {
56         std::lock_guard<std::mutex> lock(namedCallbackMapMutex_);
57         auto it = namedCallbackMap_.find(eventName);
58         if (it == namedCallbackMap_.end()) {
59             auto callbackList = std::make_shared<CallbackList>();
60             namedCallbackMap_.emplace(eventName, callbackList);
61             return *callbackList;
62         }
63         return *it->second;
64     }
65 
66     mutable std::mutex namedCallbackMapMutex_;
67     mutable std::unordered_map<std::string, std::shared_ptr<CallbackList>> namedCallbackMap_;
68 };
69 } // namespace CameraStandard
70 } // namespace OHOS
71 #endif /* LISTENER_BASE_H_ */
72