//
// Created by Patrick Maschek on 08/04/2024.
//

#ifndef CONST_CONTAINER_TEST_DEFINE_TEST_HPP_
#define CONST_CONTAINER_TEST_DEFINE_TEST_HPP_

#include <array>
#include <concepts>
#include <tuple>

#include "test_ret_val.h"

template<std::invocable Func>
struct test_def_base {
	using FuncType = Func;
	
	const char *name;
	Func func;
	
	constexpr test_def_base(const char * name, Func func) : name(name), func(func) {}
	
	virtual constexpr std::invoke_result_t<Func> operator()() { return std::apply(func, std::make_tuple()); }
};

template<std::invocable Func, typename ...Args>
struct test_definition : public test_def_base<Func> {
	using base = test_def_base<Func>;
	static constexpr std::size_t ARG_SIZE = sizeof...(Args);
	
	std::tuple<Args...> args;
	
	constexpr test_definition(const char *name, Func func, Args ...args) 
		: test_def_base<Func>(name, func), args(std::make_tuple(args...)) {}
	
	constexpr std::invoke_result_t<Func, Args...> operator()() override { return std::apply(base::func, args); }
};


struct test_suite_base {
	const char *name;
};

template<typename ...TestDefs>
	requires (sizeof...(TestDefs) == 0 || (std::derived_from<TestDefs, test_def_base<typename TestDefs::FuncType>> && ...))
struct test_suite : public test_suite_base {
	
	static constexpr std::size_t TEST_NR = sizeof...(TestDefs);
	
	std::tuple<TestDefs...> tests;
	
	constexpr test_suite(const char *name, std::tuple<TestDefs...> tests) : test_suite_base(name), tests(tests) {}
	
	constexpr ret_val<TEST_NR> run() {
		
		std::vector<ret_val_s> v;
		std::apply([&v](auto&& ...args) { ((v.push_back(args())), ...); }, tests);
		
		ret_val<TEST_NR> ret = { name };
		std::ranges::move(v, ret.vals.begin());
		
		return ret;
	}
};

template<typename Suite>
struct quick_test_def {
	Suite current;
	
	template<std::invocable Func, typename ...Args>
	constexpr auto operator()(const char *name, Func func, Args... args) {
		auto test = test_definition(name, func, args...);
		auto new_suite = test_suite(current.name, std::tuple_cat(current.tests, std::make_tuple(test)));
		return quick_test_def<decltype(new_suite)> { new_suite };
	}
	
	constexpr operator Suite() {
		return current;
	}
};

template<typename ...TestDefs>
test_suite(quick_test_def<test_suite<TestDefs...>>) -> test_suite<TestDefs...>;

constexpr auto define_tests(const char *name) {
	return quick_test_def { test_suite<>{ name, std::make_tuple() } };
}

#endif //CONST_CONTAINER_TEST_DEFINE_TEST_HPP_