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 CORE3D__LOADER__JSON_UTIL_H
17 #define CORE3D__LOADER__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/log.h>
27 #include <core/namespace.h>
28 
29 #include "util/string_util.h"
30 
CORE3D_BEGIN_NAMESPACE()31 CORE3D_BEGIN_NAMESPACE()
32 template<class T, BASE_NS::enable_if_t<BASE_NS::is_arithmetic_v<T>, bool> = true>
33 inline bool SafeGetJsonValue(
34     const CORE_NS::json::value& jsonData, const BASE_NS::string_view element, BASE_NS::string& error, T& output)
35 {
36     if (auto const pos = jsonData.find(element); pos) {
37         if (pos->is_number()) {
38             output = pos->as_number<T>();
39             return true;
40         } else {
41             error += element + ": expected number.\n";
42         }
43     }
44     return false;
45 }
46 
47 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)48 inline bool SafeGetJsonValue(
49     const CORE_NS::json::value& jsonData, const BASE_NS::string_view element, BASE_NS::string& error, T& output)
50 {
51     if (auto const pos = jsonData.find(element); pos) {
52         if (pos->is_string()) {
53             output = T(pos->string_.data(), pos->string_.size());
54             return true;
55         } else {
56             error += element + ": expected string.\n";
57         }
58     }
59     return false;
60 }
61 
62 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)63 inline bool FromJson(const CORE_NS::json::value& jsonData, T& result)
64 {
65     if (jsonData.is_boolean()) {
66         result = static_cast<T>(jsonData.boolean_);
67         return true;
68     }
69     return false;
70 }
71 
72 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)73 inline bool FromJson(const CORE_NS::json::value& jsonData, T& result)
74 {
75     if (jsonData.is_number()) {
76         result = jsonData.as_number<T>();
77         return true;
78     }
79     return false;
80 }
81 
82 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)83 inline bool FromJson(const CORE_NS::json::value& jsonData, T& result)
84 {
85     if (jsonData.is_string()) {
86         result = BASE_NS::string_view { jsonData.string_ };
87         return true;
88     }
89     return false;
90 }
91 
92 namespace Detail {
93 constexpr const BASE_NS::string_view INVALID_DATATYPE = "Failed to read value, invalid datatype: ";
94 template<typename T>
Convert(const CORE_NS::json::value & value)95 inline T Convert(const CORE_NS::json::value& value)
96 {
97     T result;
98     FromJson(value, result);
99     return result;
100 }
101 
102 template<typename Container, typename OutIt, typename Fn>
Transform(Container && container,OutIt dest,Fn func)103 inline OutIt Transform(Container&& container, OutIt dest, Fn func)
104 {
105     return std::transform(container.begin(), container.end(), dest, func);
106 }
107 } // namespace Detail
108 
109 template<class JsonType, typename T>
FromJson(const JsonType & jsonData,BASE_NS::array_view<T> container)110 inline void FromJson(const JsonType& jsonData, BASE_NS::array_view<T> container)
111 {
112     if (jsonData.is_array()) {
113         const auto view =
114             BASE_NS::array_view(jsonData.array_.data(), BASE_NS::Math::min(jsonData.array_.size(), container.size()));
115         Detail::Transform(view, std::begin(container), [](const JsonType& value) { return Detail::Convert<T>(value); });
116     }
117 }
118 
119 template<class JsonType, typename T>
FromJson(const JsonType & jsonData,BASE_NS::vector<T> & container)120 inline void FromJson(const JsonType& jsonData, BASE_NS::vector<T>& container)
121 {
122     if (jsonData.is_array()) {
123         Detail::Transform(jsonData.array_, std::back_inserter(container),
124             [](const JsonType& value) { return Detail::Convert<T>(value); });
125     }
126 }
127 
128 template<class JsonType, typename T, size_t N>
FromJson(const JsonType & jsonData,T (& container)[N])129 inline void FromJson(const JsonType& jsonData, T (&container)[N])
130 {
131     FromJson(jsonData, BASE_NS::array_view(container));
132 }
133 
134 template<class JsonType, typename T,
135     BASE_NS::enable_if_t<BASE_NS::is_array_v<decltype(T::data)> &&
136                              BASE_NS::is_arithmetic_v<BASE_NS::remove_extent_t<decltype(T::data)>>,
137         bool> = true>
FromJson(const JsonType & jsonData,T & output)138 inline void FromJson(const JsonType& jsonData, T& output)
139 {
140     FromJson(jsonData, output.data);
141 }
142 CORE3D_END_NAMESPACE()
143 
144 #endif