#include <boost/test/unit_test.hpp>

#include <boost/asio/detached.hpp>
#include <boost/asio/io_context.hpp>
#include <boost/asio/steady_timer.hpp>

#include <async_mqtt5/mqtt_client.hpp>

#include "test_common/message_exchange.hpp"
#include "test_common/test_broker.hpp"
#include "test_common/test_stream.hpp"

using namespace async_mqtt5;

BOOST_AUTO_TEST_SUITE(disconnect/*, *boost::unit_test::disabled()*/)

struct shared_test_data {
	error_code success {};
	error_code fail = asio::error::not_connected;

	const std::string connect = encoders::encode_connect(
		"", std::nullopt, std::nullopt, 60, false, {}, std::nullopt
	);
	const std::string connack = encoders::encode_connack(
		true, reason_codes::success.value(), {}
	);
	const std::string disconnect = encoders::encode_disconnect(
		reason_codes::normal_disconnection.value(), disconnect_props {}
	);
};

using test::after;
using namespace std::chrono_literals;
using client_type = mqtt_client<test::test_stream>;

template <typename TestCase>
void run_test(test::msg_exchange broker_side, TestCase&& test_case) {
	asio::io_context ioc;
	auto executor = ioc.get_executor();
	auto& broker = asio::make_service<test::test_broker>(
		ioc, executor, std::move(broker_side)
	);

	asio::steady_timer timer(executor);
	client_type c(executor);
	c.brokers("127.0.0.1,127.0.0.1") // to avoid reconnect backoff
		.async_run(asio::detached);

	test_case(c, timer);

	ioc.run();
	BOOST_TEST(broker.received_all_expected());
}

BOOST_FIXTURE_TEST_CASE(successful_disconnect, shared_test_data) {
	constexpr int expected_handlers_called = 1;
	int handlers_called = 0;

	test::msg_exchange broker_side;
	broker_side
		.expect(connect)
			.complete_with(success, after(0ms))
			.reply_with(connack, after(0ms))
		.expect(disconnect)
			.complete_with(success, after(0ms));

	run_test(
		std::move(broker_side),
		[&](client_type& c, asio::steady_timer& timer) {
			timer.expires_after(100ms);
			timer.async_wait([&](error_code) {
				c.async_disconnect(
					[&](error_code ec) {
						handlers_called++;
						BOOST_TEST(!ec);
					}
				);
			});
		}
	);

	BOOST_TEST(handlers_called == expected_handlers_called);
}

BOOST_FIXTURE_TEST_CASE(successful_disconnect_in_queue, shared_test_data) {
	constexpr int expected_handlers_called = 2;
	int handlers_called = 0;

	// packets
	auto publish_qos0 = encoders::encode_publish(
		0, "topic", "payload", qos_e::at_most_once, retain_e::no, dup_e::no, {}
	);

	test::msg_exchange broker_side;
	broker_side
		.expect(connect)
			.complete_with(success, after(1ms))
			.reply_with(connack, after(2ms))
		.expect(publish_qos0)
			.complete_with(success, after(1ms))
		.expect(disconnect)
			.complete_with(success, after(0ms));

	run_test(
		std::move(broker_side),
		[&](client_type& c, asio::steady_timer& timer) {
			timer.expires_after(50ms);
			timer.async_wait([&](error_code) {
				c.async_publish<qos_e::at_most_once>(
					"topic", "payload", retain_e::no, {},
					[&handlers_called](error_code ec) {
						BOOST_TEST(handlers_called == 0);
						handlers_called++;
						BOOST_TEST(!ec);
					}
				);
				c.async_disconnect(
					[&](error_code ec) {
						BOOST_TEST(handlers_called == 1);
						handlers_called++;
						BOOST_TEST(!ec);
					}
				);
			});
		}
	);

	BOOST_TEST(handlers_called == expected_handlers_called);
}

BOOST_FIXTURE_TEST_CASE(disconnect_on_disconnected_client, shared_test_data) {
	constexpr int expected_handlers_called = 1;
	int handlers_called = 0;

	test::msg_exchange broker_side;
	broker_side
		.expect(connect)
		.expect(connect);

	run_test(
		std::move(broker_side),
		[&](client_type& c, asio::steady_timer& timer) {
			timer.expires_after(50ms);
			timer.async_wait([&](error_code) {
				c.async_disconnect(
					[&](error_code ec) {
						handlers_called++;
						BOOST_TEST(ec == asio::error::operation_aborted);
					}
				);
			});
		}
	);

	BOOST_TEST(handlers_called == expected_handlers_called);
}

BOOST_FIXTURE_TEST_CASE(disconnect_in_queue_on_disconnected_client, shared_test_data) {
	constexpr int expected_handlers_called = 2;
	int handlers_called = 0;

	test::msg_exchange broker_side;
	broker_side
		.expect(connect)
		.expect(connect);

	run_test(
		std::move(broker_side),
		[&](client_type& c, asio::steady_timer& timer) {
			timer.expires_after(50ms);
			timer.async_wait([&](error_code) {
				c.async_publish<qos_e::at_most_once>(
					"topic", "payload", retain_e::no, {},
					[&handlers_called](error_code ec) {
						BOOST_TEST(handlers_called == 1);
						handlers_called++;
						BOOST_TEST(ec == asio::error::operation_aborted);
					}
				);
				c.async_disconnect(
					[&](error_code ec) {
						BOOST_TEST(handlers_called == 0);
						handlers_called++;
						BOOST_TEST(ec == asio::error::operation_aborted);
					}
				);
			});
		}
	);

	BOOST_TEST(handlers_called == expected_handlers_called);
}

BOOST_FIXTURE_TEST_CASE(resend_terminal_disconnect, shared_test_data) {
	constexpr int expected_handlers_called = 1;
	int handlers_called = 0;

	test::msg_exchange broker_side;
	broker_side
		.expect(connect)
			.complete_with(success, after(0ms))
			.reply_with(connack, after(0ms))
		.expect(disconnect)
			.complete_with(success, after(0ms));

	run_test(
		std::move(broker_side),
		[&](client_type& c, asio::steady_timer&) {
			c.async_disconnect(
				[&](error_code ec) {
					handlers_called++;
					BOOST_TEST(!ec);
				}
			);
		}
	);

	BOOST_TEST(handlers_called == expected_handlers_called);
}

BOOST_FIXTURE_TEST_CASE(dont_resend_non_terminal_disconnect, shared_test_data) {
	auto malformed_publish_1 = encoders::encode_publish(
		1, "malformed topic", "malformed payload",
		static_cast<qos_e>(0b11), retain_e::yes, dup_e::no, {}
	);
	auto malformed_publish_2 = encoders::encode_publish(
		2, "malformed topic", "malformed payload",
		static_cast<qos_e>(0b11), retain_e::yes, dup_e::no, {}
	);

	auto disconnect_malformed_publish = encoders::encode_disconnect(
		reason_codes::malformed_packet.value(),
		test::dprops_with_reason_string("Malformed PUBLISH received: QoS bits set to 0b11")
	);

	test::msg_exchange broker_side;
	broker_side
		.expect(connect)
			.complete_with(success, after(0ms))
			.reply_with(connack, after(0ms))
		.send(malformed_publish_1, malformed_publish_2, after(10ms))
		.expect(disconnect_malformed_publish)
			.complete_with(success, after(0ms))
		.expect(connect)
			.complete_with(success, after(0ms))
			.reply_with(connack, after(0ms));

	run_test(
		std::move(broker_side),
		[&](client_type& c, asio::steady_timer& timer) {
			timer.expires_after(50ms);
			timer.async_wait([&](error_code) {
				c.cancel();
			});
		}
	);
}

BOOST_FIXTURE_TEST_CASE(omit_props, shared_test_data) {
	constexpr int expected_handlers_called = 1;
	int handlers_called = 0;

	connack_props co_props;
	co_props[prop::maximum_packet_size] = 20;

	// packets
	auto connack_with_max_packet = encoders::encode_connack(
		false, reason_codes::success.value(), co_props
	);

	disconnect_props props;
	props[prop::reason_string] = std::string(50, 'a');
	auto big_disconnect = encoders::encode_disconnect(
		reason_codes::normal_disconnection.value(), props
	);

	test::msg_exchange broker_side;
	broker_side
		.expect(connect)
			.complete_with(success, after(0ms))
			.reply_with(connack_with_max_packet, after(0ms))
		.expect(disconnect)
			.complete_with(success, after(0ms));

	run_test(
		std::move(broker_side),
		[&](client_type& c, asio::steady_timer& timer) {
			timer.expires_after(50ms);
			timer.async_wait([&](error_code) {
				c.async_disconnect(
					disconnect_rc_e::normal_disconnection, props,
					[&](error_code ec) {
						handlers_called++;
						BOOST_TEST(!ec);
					}
				);
			});
		}
	);

	BOOST_TEST(handlers_called == expected_handlers_called);
}

BOOST_AUTO_TEST_SUITE_END()