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 UTIL__JSON_UTIL_H
17 #define UTIL__JSON_UTIL_H
18
19 #include <algorithm>
20 #include <cstdlib>
21
22 #include <base/containers/string.h>
23 #include <base/containers/string_view.h>
24 #include <base/math/mathf.h>
25 #include <core/json/json.h>
26 #include <core/namespace.h>
27 #include <render/namespace.h>
28
RENDER_BEGIN_NAMESPACE()29 RENDER_BEGIN_NAMESPACE()
30 template<class T, BASE_NS::enable_if_t<BASE_NS::is_arithmetic_v<T>, bool> = true>
31 inline bool SafeGetJsonValue(
32 const CORE_NS::json::value& jsonData, const BASE_NS::string_view element, BASE_NS::string& error, T& output)
33 {
34 if (auto const pos = jsonData.find(element); pos) {
35 if (pos->is_number()) {
36 output = pos->as_number<T>();
37 return true;
38 } else {
39 error += element + ": expected number.\n";
40 }
41 }
42 return false;
43 }
44
45 template<class T, BASE_NS::enable_if_t<BASE_NS::is_convertible_v<T, BASE_NS::string_view>, bool> = true>
SafeGetJsonValue(const CORE_NS::json::value & jsonData,const BASE_NS::string_view element,BASE_NS::string & error,T & output)46 inline bool SafeGetJsonValue(
47 const CORE_NS::json::value& jsonData, const BASE_NS::string_view element, BASE_NS::string& error, T& output)
48 {
49 if (auto const pos = jsonData.find(element); pos) {
50 if (pos->is_string()) {
51 output = T(pos->string_.data(), pos->string_.size());
52 return true;
53 } else {
54 error += element + ": expected string.\n";
55 }
56 }
57 return false;
58 }
59
60 template<typename T, BASE_NS::enable_if_t<BASE_NS::is_same_v<bool, T>, bool> = true>
FromJson(const CORE_NS::json::value & jsonData,T & result)61 inline bool FromJson(const CORE_NS::json::value& jsonData, T& result)
62 {
63 if (jsonData.is_boolean()) {
64 result = static_cast<T>(jsonData.boolean_);
65 return true;
66 }
67 return false;
68 }
69
70 template<typename T, BASE_NS::enable_if_t<!BASE_NS::is_same_v<bool, T> && BASE_NS::is_arithmetic_v<T>, bool> = true>
FromJson(const CORE_NS::json::value & jsonData,T & result)71 inline bool FromJson(const CORE_NS::json::value& jsonData, T& result)
72 {
73 if (jsonData.is_number()) {
74 result = jsonData.as_number<T>();
75 return true;
76 }
77 return false;
78 }
79
80 template<typename T, BASE_NS::enable_if_t<BASE_NS::is_convertible_v<T, BASE_NS::string_view>, bool> = true>
FromJson(const CORE_NS::json::value & jsonData,T & result)81 inline bool FromJson(const CORE_NS::json::value& jsonData, T& result)
82 {
83 if (jsonData.is_string()) {
84 result = BASE_NS::string_view { jsonData.string_ };
85 return true;
86 }
87 return false;
88 }
89
90 namespace Detail {
91 constexpr const BASE_NS::string_view INVALID_DATATYPE = "Failed to read value, invalid datatype: ";
92 template<typename T>
Convert(const CORE_NS::json::value & value)93 inline T Convert(const CORE_NS::json::value& value)
94 {
95 T result;
96 FromJson(value, result);
97 return result;
98 }
99
100 template<typename Container, typename OutIt, typename Fn>
Transform(Container && container,OutIt dest,Fn func)101 inline OutIt Transform(Container&& container, OutIt dest, Fn func)
102 {
103 return std::transform(container.begin(), container.end(), dest, func);
104 }
105 } // namespace Detail
106
107 template<class JsonType, typename T>
FromJson(const JsonType & jsonData,BASE_NS::array_view<T> container)108 inline void FromJson(const JsonType& jsonData, BASE_NS::array_view<T> container)
109 {
110 if (jsonData.is_array()) {
111 const auto view =
112 BASE_NS::array_view(jsonData.array_.data(), BASE_NS::Math::min(jsonData.array_.size(), container.size()));
113 Detail::Transform(view, std::begin(container), [](const JsonType& value) { return Detail::Convert<T>(value); });
114 }
115 }
116
117 template<class JsonType, typename T>
FromJson(const JsonType & jsonData,BASE_NS::vector<T> & container)118 inline void FromJson(const JsonType& jsonData, BASE_NS::vector<T>& container)
119 {
120 if (jsonData.is_array()) {
121 Detail::Transform(jsonData.array_, std::back_inserter(container),
122 [](const JsonType& value) { return Detail::Convert<T>(value); });
123 }
124 }
125
126 template<class JsonType, typename T, size_t N>
FromJson(const JsonType & jsonData,T (& container)[N])127 inline void FromJson(const JsonType& jsonData, T (&container)[N])
128 {
129 FromJson(jsonData, BASE_NS::array_view(container));
130 }
131
132 template<class JsonType, typename T,
133 BASE_NS::enable_if_t<BASE_NS::is_array_v<decltype(T::data)> &&
134 BASE_NS::is_arithmetic_v<BASE_NS::remove_extent_t<decltype(T::data)>>,
135 bool> = true>
FromJson(const JsonType & jsonData,T & output)136 inline void FromJson(const JsonType& jsonData, T& output)
137 {
138 FromJson(jsonData, output.data);
139 }
140 RENDER_END_NAMESPACE()
141 #endif // UTIL__JSON_UTIL_H