Add json array property parsing, helper functions

inferno/src/inferno/util/json.h

@@ -1,7 +1,9 @@
 #ifndef JSON_UTIL_H
 #define JSON_UTIL_H
 
+#include <cstdint>  // int32_t, uint32_t
 #include <optional> // std::optional
+#include <vector>   // std::vector
 
 #include "nlohmann/json.hpp"
 
@@ -19,8 +21,8 @@ namespace Inferno {
 			return it.value();
 		}
 
-		template<typename T, typename C>
-		static std::optional<T> getType(const json& json, C check)
+		template<typename T>
+		static std::optional<T> getPropertyValue(const json& json, json::value_t check)
 		{
 			if (json.type() == check) {
 				return json.get<T>();
@@ -29,36 +31,146 @@ namespace Inferno {
 			return {};
 		}
 
+		template<typename T>
+		static std::optional<T> getPropertyValue(const json& json, std::vector<json::value_t> checks)
+		{
+			bool valid = false;
+
+			// Check values with all allowed types
+			for (auto check : checks) {
+				if (json.type() == check) {
+					valid = true;
+					break;
+				}
+			}
+
+			// Get value if valid type
+			if (valid) {
+				return json.get<T>();
+			}
+
+			return {};
+		}
+
 		// ---------------------------------
 
-		static bool hasProperty(const json& json, json_const_iterator& it, const char* member)
+		static bool hasProperty(const json& json, const char* property)
 		{
-			it = json.find(member);
+			return json.find(property) != json.end();
+		}
+
+		static bool hasProperty(const json& json, json_const_iterator& it, const char* property)
+		{
+			it = json.find(property);
 			return it != json.end();
 		}
 
 		// ---------------------------------
 
-		template<typename T, typename C>
-		static std::optional<T> parseProperty(const json& json, const char* property, bool required, C check)
+		template<typename T>
+		static std::optional<T> parseProperty(const json& json, const char* property, bool required, json::value_t check)
+		{
+			return parseProperty<T>(json, property, required, std::vector { check });
+		}
+
+		template<typename T>
+		static std::optional<T> parseProperty(const json& json, const char* property, bool required, std::vector<json::value_t> checks)
 		{
-			bool result;
+			bool exists;
 			json_const_iterator it;
 
 			// Has property
-			result = hasProperty(json, it, property);
-			ASSERT(!required || (required && result), "Json could not find property '{}'", property);
+			exists = hasProperty(json, it, property);
+			ASSERT(!required || (required && exists), "Json could not find required property '{}'", property);
 
-			if (!result) {
+			if (!exists) {
 				return {};
 			}
 
 			// Return data found in iterator, empty if incorrect type
-			return getType<T>(getValue(it), check);
+			return getPropertyValue<T>(getValue(it), checks);
+		}
+
+		template<typename T>
+		static std::optional<std::vector<T>> parseArrayProperty(const json& json, const char* property, bool required, json::value_t check)
+		{
+			return parseArrayProperty<T>(json, property, required, std::vector { check });
+		}
+
+		template<typename T>
+		static std::optional<std::vector<T>> parseArrayProperty(const json& json, const char* property, bool required, std::vector<json::value_t> checks)
+		{
+			bool exists;
+			json_const_iterator it;
+
+			// Has property
+			exists = hasProperty(json, it, property);
+			ASSERT(!required || (required && exists), "Json could not find required property '{}'", property);
+
+			if (!exists) {
+				return {};
+			}
+
+			// Check if property is array
+			ASSERT(getValue(it).is_array(), "Json property is not an array '{}'", property);
+
+			// Fill array with values
+			std::vector<T> values;
+			for (auto value : getValue(it)) {
+				auto typedValue = getPropertyValue<T>(value, checks);
+				if (typedValue) {
+					values.emplace_back(typedValue.value());
+				}
+				else {
+					warnln("Json array property '{}' has type inconsistency", property);
+				}
+			}
+
+			return values.size() > 0 ? std::optional { values } : std::nullopt;
+		}
+
+		static std::optional<bool> parseBoolProperty(const json& json, const char* property, bool required)
+		{
+			return parseProperty<bool>(json, property, required, json::value_t::boolean);
+		}
+
+		static std::optional<double> parseDoubleProperty(const json& json, const char* property, bool required)
+		{
+			return parseProperty<double>(json, property, required, std::vector { json::value_t::number_integer, json::value_t::number_unsigned, json::value_t::number_float });
+		}
+
+		static std::optional<int32_t> parseIntegerProperty(const json& json, const char* property, bool required)
+		{
+			return parseProperty<int32_t>(json, property, required, json::value_t::number_integer);
+		}
+
+		static std::optional<uint32_t> parseUnsignedProperty(const json& json, const char* property, bool required)
+		{
+			return parseProperty<uint32_t>(json, property, required, json::value_t::number_unsigned);
 		}
+
+		static std::optional<std::string> parseStringProperty(const json& json, const char* property, bool required)
+		{
+			return parseProperty<std::string>(json, property, required, json::value_t::string);
+		}
+
+		static std::optional<std::vector<double>> parseDoubleArrayProperty(const json& json, const char* property, bool required)
+		{
+			return parseArrayProperty<double>(json, property, required, std::vector { json::value_t::number_integer, json::value_t::number_unsigned, json::value_t::number_float });
+		}
+
+		static std::optional<std::vector<int32_t>> parseIntegerArrayProperty(const json& json, const char* property, bool required)
+		{
+			return parseArrayProperty<int32_t>(json, property, required, json::value_t::number_integer);
+		}
+
+		static std::optional<std::vector<uint32_t>> parseUnsignedArrayProperty(const json& json, const char* property, bool required)
+		{
+			return parseArrayProperty<uint32_t>(json, property, required, json::value_t::number_unsigned);
+		}
+
 	};
 
 } // namespace Inferno
 
-
 #endif // JSON_UTIL_H