// Copyright ⓒ 2018-2021 ThePhD.
//
// Licensed under the Apache License, Version 2.0 (the "License");
// you may not use this file except in compliance with the License.
// You may obtain a copy of the License at
//
//     http://www.apache.org/licenses/LICENSE-2.0
//
// Unless required by applicable law or agreed to in writing, software
// distributed under the License is distributed on an "AS IS" BASIS,
// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
// See the License for the specific language governing permissions and
// limitations under the License.
//
//  See https://github.com/ThePhD/out_ptr/blob/master/docs/out_ptr.adoc for documentation.

#include <ztd/out_ptr/inout_ptr.hpp>
#include <ztd/out_ptr/detail/integer_sequence.hpp>

#include <phd/handle.hpp>

#include <ficapi/ficapi.hpp>

#include <catch2/catch.hpp>

// A template that always evaluates to false anyhow
template <std::size_t I>
struct always_false_index : std::integral_constant<bool, I == 1 && I == 0> {};

namespace ztd {
	template <typename T, typename D>
	class special_inout_customization_handle : public handle<T, D> {
	private:
		using base_t = handle<T, D>;

	public:
		using base_t::base_t;
	};
} // namespace ztd

namespace ztd { namespace out_ptr {

	template <typename T, typename D, typename Pointer, typename... Args>
	class inout_ptr_t<ztd::special_inout_customization_handle<T, D>, Pointer, Args...> : std::tuple<Args...> {
	private:
		using Smart		 = ztd::special_inout_customization_handle<T, D>;
		using source_pointer = pointer_of_or_t<Smart, Pointer>;
		using ArgsTuple	 = std::tuple<Args...>;
		using Base		 = ArgsTuple;

		Pointer* m_target_ptr;

	public:
		inout_ptr_t(Smart& s, Args... args) noexcept
		: Base(std::forward<Args>(args)...), m_target_ptr(reinterpret_cast<Pointer*>(std::addressof(s.get()))) {
		}

		inout_ptr_t(inout_ptr_t&& right) noexcept
		: Base(std::move(right)), m_target_ptr(right.m_target_ptr) {
		}
		inout_ptr_t& operator=(inout_ptr_t&& right) noexcept {
			Base::operator	=(std::move(right));
			this->m_target_ptr = right.m_target_ptr;
			return *this;
		}

		operator Pointer*() const noexcept {
			return const_cast<Pointer*>(this->m_target_ptr);
		}

		~inout_ptr_t() noexcept {
			static_assert(sizeof...(Args) < 1, "you cannot reset the deleter for handle<T, Deleter>!: it only takes one argument!");
		}
	};

}} // namespace ztd::out_ptr

TEST_CASE("inout_ptr/customization basic", "inout_ptr type works with smart pointers and C-style output APIs") {
	SECTION("handle<void*>") {
		ztd::special_inout_customization_handle<void*, ficapi::deleter<>> p(nullptr);
		ficapi_re_create(ztd::out_ptr::inout_ptr(p), ficapi_type::ficapi_type_int);
		int* rawp = static_cast<int*>(p.get());
		REQUIRE(rawp != nullptr);
		REQUIRE(*rawp == ficapi_get_dynamic_data());
	}
	SECTION("handle<int*>") {
		ztd::special_inout_customization_handle<int*, ficapi::int_deleter> p(nullptr);
		ficapi_int_re_create(ztd::out_ptr::inout_ptr(p));
		int* rawp = p.get();
		REQUIRE(rawp != nullptr);
		REQUIRE(*rawp == ficapi_get_dynamic_data());
	}
	SECTION("handle<ficapi::opaque*>") {
		ztd::special_inout_customization_handle<ficapi::opaque*, ficapi::handle_deleter> p(nullptr);
		ficapi_handle_re_create(ztd::out_ptr::inout_ptr(p));
		ficapi::opaque_handle rawp = p.get();
		REQUIRE(rawp != nullptr);
		REQUIRE(ficapi_handle_get_data(rawp) == ficapi_get_dynamic_data());
	}
	SECTION("handle<ficapi::opaque*>, void inout_ptr") {
		ztd::special_inout_customization_handle<ficapi::opaque*, ficapi::handle_deleter> p(nullptr);
		ficapi_re_create(ztd::out_ptr::inout_ptr<void*>(p), ficapi_type::ficapi_type_opaque);
		ficapi::opaque_handle rawp = p.get();
		REQUIRE(rawp != nullptr);
		REQUIRE(ficapi_handle_get_data(rawp) == ficapi_get_dynamic_data());
	}
#if 0 // this no longer applies because there is no implicit void* conversion...
	SECTION("handle<void*>, ficapi::opaque_handle inout_ptr") {
		ztd::special_inout_customization_handle<void*, ficapi::deleter<ficapi_type::ficapi_type_opaque>> p(nullptr);
		ficapi_re_create(ztd::out_ptr::inout_ptr<ficapi::opaque_handle>(p), ficapi::type::ficapi_type_opaque);
		ficapi::opaque_handle rawp = static_cast<ficapi::opaque_handle>(p.get());
		REQUIRE(rawp != nullptr);
		REQUIRE(ficapi_handle_get_data(rawp) == ficapi_get_dynamic_data());
	}
#endif
}

TEST_CASE("inout_ptr/customization stateful", "inout_ptr type works with stateful deleters in smart pointers") {
	SECTION("handle<void*, stateful_deleter>") {
		ztd::special_inout_customization_handle<void*, ficapi::stateful_deleter> p(nullptr, ficapi::stateful_deleter{ 0x12345678, ficapi_type::ficapi_type_int });
		ficapi_re_create(ztd::out_ptr::inout_ptr(p), ficapi_type::ficapi_type_int);
		int* rawp = static_cast<int*>(p.get());
		REQUIRE(rawp != nullptr);
		REQUIRE(*rawp == ficapi_get_dynamic_data());
		REQUIRE(p.get_deleter().state() == 0x12345678);
	}
	SECTION("handle<int*, stateful_deleter>") {
		ztd::special_inout_customization_handle<int*, ficapi::stateful_int_deleter> p(nullptr, ficapi::stateful_int_deleter{ 0x12345678 });
		ficapi_int_re_create(ztd::out_ptr::inout_ptr(p));
		int* rawp = p.get();
		REQUIRE(rawp != nullptr);
		REQUIRE(*rawp == ficapi_get_dynamic_data());
		REQUIRE(p.get_deleter().state() == 0x12345678);
	}
	SECTION("handle<ficapi::opaque*, stateful_handle_deleter>") {
		ztd::special_inout_customization_handle<ficapi::opaque*, ficapi::stateful_handle_deleter> p(nullptr, ficapi::stateful_handle_deleter{ 0x12345678 });
		ficapi_handle_re_create(ztd::out_ptr::inout_ptr(p));
		ficapi::opaque_handle rawp = p.get();
		REQUIRE(rawp != nullptr);
		REQUIRE(ficapi_handle_get_data(rawp) == ficapi_get_dynamic_data());
		REQUIRE(p.get_deleter().state() == 0x12345678);
	}
	SECTION("handle<ficapi::opaque*, stateful_deleter>, void inout_ptr") {
		ztd::special_inout_customization_handle<ficapi::opaque*, ficapi::stateful_deleter> p(nullptr, ficapi::stateful_deleter{ 0x12345678, ficapi_type::ficapi_type_int });
		ficapi_re_create(ztd::out_ptr::inout_ptr<void*>(p), ficapi_type::ficapi_type_opaque);
		ficapi::opaque_handle rawp = p.get();
		REQUIRE(rawp != nullptr);
		REQUIRE(ficapi_handle_get_data(rawp) == ficapi_get_dynamic_data());
		REQUIRE(p.get_deleter().state() == 0x12345678);
	}
}

TEST_CASE("inout_ptr/customization reused", "inout_ptr type properly deletes non-nullptr types from earlier") {
	struct reused_deleter {
		int store = 0;

		void operator()(void* x) {
			++store;
			ficapi_delete(x, ficapi_type::ficapi_type_int);
		}
	};
	struct reused_int_deleter {
		int store = 0;

		void operator()(int* x) {
			++store;
			ficapi_int_delete(x);
		}
	};
	SECTION("handle<void*, stateful_deleter>") {
		ztd::special_inout_customization_handle<void*, reused_deleter> p(nullptr, reused_deleter{});

		ficapi_re_create(ztd::out_ptr::inout_ptr(p), ficapi_type::ficapi_type_int);
		{
			int* rawp = static_cast<int*>(p.get());
			REQUIRE(rawp != nullptr);
			REQUIRE(*rawp == ficapi_get_dynamic_data());
			REQUIRE(p.get_deleter().store == 0);
		}
		ficapi_re_create(ztd::out_ptr::inout_ptr(p), ficapi_type::ficapi_type_int);
		{
			int* rawp = static_cast<int*>(p.get());
			REQUIRE(rawp != nullptr);
			REQUIRE(*rawp == ficapi_get_dynamic_data());
			REQUIRE(p.get_deleter().store == 0);
		}
		ficapi_int_re_create(ztd::out_ptr::inout_ptr<int*>(p));
		{
			int* rawp = static_cast<int*>(p.get());
			REQUIRE(rawp != nullptr);
			REQUIRE(*rawp == ficapi_get_dynamic_data());
			REQUIRE(p.get_deleter().store == 0);
		}
	}
	SECTION("handle<int*, stateful_deleter>") {
		ztd::special_inout_customization_handle<int*, reused_int_deleter> p(nullptr, reused_int_deleter{});

		ficapi_int_re_create(ztd::out_ptr::inout_ptr(p));
		{
			int* rawp = p.get();
			REQUIRE(rawp != nullptr);
			REQUIRE(*rawp == ficapi_get_dynamic_data());
			REQUIRE(p.get_deleter().store == 0);
		}
		ficapi_int_re_create(ztd::out_ptr::inout_ptr(p));
		{
			int* rawp = p.get();
			REQUIRE(rawp != nullptr);
			REQUIRE(*rawp == ficapi_get_dynamic_data());
			REQUIRE(p.get_deleter().store == 0);
		}
		ficapi_re_create(ztd::out_ptr::inout_ptr<void*>(p), ficapi_type::ficapi_type_int);
		{
			int* rawp = p.get();
			REQUIRE(rawp != nullptr);
			REQUIRE(*rawp == ficapi_get_dynamic_data());
			REQUIRE(p.get_deleter().store == 0);
		}
	}
}