1 /*
2 * Copyright (c) 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 API_CORE_ECS_ISYSTEM_GRAPH_H
17 #define API_CORE_ECS_ISYSTEM_GRAPH_H
18
19 #include <base/containers/refcnt_ptr.h>
20 #include <base/containers/string.h>
21 #include <base/containers/string_view.h>
22 #include <base/containers/unique_ptr.h>
23 #include <base/namespace.h>
24 #include <base/util/uid.h>
25 #include <core/namespace.h>
26 #include <core/plugin/intf_interface.h>
27
28 CORE_BEGIN_NAMESPACE()
29 class IFileManager;
30 class IEcs;
31
32 /** @ingroup group_ecs_isystemgraph */
33 /**
34 * ISystemGraphLoader.
35 * Interface class for creating a SystemGraphDesc from a JSON file.
36 */
37 class ISystemGraphLoader {
38 public:
39 /** Describes result of the loading operation. */
40 struct LoadResult {
41 LoadResult() = default;
LoadResultLoadResult42 explicit LoadResult(BASE_NS::string&& error) : success(false), error(BASE_NS::move(error)) {}
43
44 /** Indicates, whether the parsing operation is successful. */
45 bool success { true };
46
47 /** In case of parsing error, contains the description of the error. */
48 BASE_NS::string error;
49 };
50
51 /** Load a system graph description from a file.
52 * @param uri URI to a file containing the system graph description in JSON format.
53 * @param ecs Ecs instance to populate with systems and components.
54 * @return If loading fails LoadResult::success is false and LoadResult::error contains an error message.
55 */
56 virtual LoadResult Load(BASE_NS::string_view uri, IEcs& ecs) = 0;
57
58 /** Load a system graph description from a JSON string.
59 * @param json String containing the system graph description in JSON format.
60 * @param ecs Ecs instance to populate with systems and components.
61 * @return If loading fails LoadResult::success is false and LoadResult::error contains an error message.
62 */
63 virtual LoadResult LoadString(BASE_NS::string_view json, IEcs& ecs) = 0;
64
65 struct Deleter {
66 constexpr Deleter() noexcept = default;
operatorDeleter67 void operator()(ISystemGraphLoader* ptr) const
68 {
69 ptr->Destroy();
70 }
71 };
72 using Ptr = BASE_NS::unique_ptr<ISystemGraphLoader, struct Deleter>;
73
74 protected:
75 ISystemGraphLoader() = default;
76 virtual ~ISystemGraphLoader() = default;
77 virtual void Destroy() = 0;
78 };
79
80 // factory inteface.
81 class ISystemGraphLoaderFactory : public IInterface {
82 public:
83 static constexpr auto UID = BASE_NS::Uid { "26f8f9de-53e9-4a09-85a6-45b69eb3efb6" };
84
85 using Ptr = BASE_NS::refcnt_ptr<ISystemGraphLoaderFactory>;
86
87 virtual ISystemGraphLoader::Ptr Create(IFileManager& fileManager) = 0;
88
89 protected:
90 ISystemGraphLoaderFactory() = default;
91 virtual ~ISystemGraphLoaderFactory() = default;
92 };
93
GetName(const ISystemGraphLoaderFactory *)94 inline constexpr BASE_NS::string_view GetName(const ISystemGraphLoaderFactory*)
95 {
96 return "ISystemGraphLoaderFactory";
97 }
98 CORE_END_NAMESPACE()
99
100 #endif // API_CORE_ECS_ISYSTEM_GRAPH_H
101