/*

Copyright (c) 2010, Arvid Norberg
All rights reserved.

Redistribution and use in source and binary forms, with or without
modification, are permitted provided that the following conditions
are met:

    * Redistributions of source code must retain the above copyright
      notice, this list of conditions and the following disclaimer.
    * Redistributions in binary form must reproduce the above copyright
      notice, this list of conditions and the following disclaimer in
      the documentation and/or other materials provided with the distribution.
    * Neither the name of the author nor the names of its
      contributors may be used to endorse or promote products derived
      from this software without specific prior written permission.

THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS"
AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT OWNER OR CONTRIBUTORS BE
LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
POSSIBILITY OF SUCH DAMAGE.

*/

#include "test.hpp"
#include "settings.hpp"
#include "setup_swarm.hpp"
#include "simulator/simulator.hpp"
#include "simulator/http_server.hpp"
#include "libtorrent/alert_types.hpp"
#include "libtorrent/announce_entry.hpp"
#include "libtorrent/session.hpp"

using namespace libtorrent;
using namespace sim;
namespace lt = libtorrent;

using chrono::duration_cast;

// seconds
const int duration = 10000;

void test_interval(int interval)
{
	using sim::asio::ip::address_v4;
	sim::default_config network_cfg;
	sim::simulation sim{network_cfg};

	lt::time_point start = lt::clock_type::now();

	sim::asio::io_service web_server(sim, address_v4::from_string("2.2.2.2"));
	// listen on port 8080
	sim::http_server http(web_server, 8080);

	// the timestamps (in seconds) of all announces
	std::vector<int> announces;

	http.register_handler("/announce"
	, [&announces,interval,start](std::string method, std::string req
		, std::map<std::string, std::string>&)
	{
		boost::uint32_t seconds = chrono::duration_cast<lt::seconds>(
			lt::clock_type::now() - start).count();
		announces.push_back(seconds);

		char response[500];
		int size = snprintf(response, sizeof(response), "d8:intervali%de5:peers0:e", interval);
		return sim::send_response(200, "OK", size) + response;
	});

	std::vector<int> announce_alerts;

	lt::settings_pack default_settings = settings();
	lt::add_torrent_params default_add_torrent;

	setup_swarm(1, swarm_test::upload, sim, default_settings, default_add_torrent
		// add session
		, [](lt::settings_pack& pack) { }
		// add torrent
		, [](lt::add_torrent_params& params) {
			params.trackers.push_back("http://2.2.2.2:8080/announce");
		}
		// on alert
		, [&](lt::alert const* a, lt::session& ses) {

			if (lt::alert_cast<lt::tracker_announce_alert>(a))
			{
				boost::uint32_t seconds = chrono::duration_cast<lt::seconds>(
					a->timestamp() - start).count();

				announce_alerts.push_back(seconds);
			}
		}
		// terminate
		, [](int ticks, lt::session& ses) -> bool { return ticks > duration; });

	TEST_EQUAL(announce_alerts.size(), announces.size());

	int counter = 0;
	for (int i = 0; i < int(announces.size()); ++i)
	{
		TEST_EQUAL(announces[i], counter);
		TEST_EQUAL(announce_alerts[i], counter);
		counter += interval;
		if (counter > duration + 1) counter = duration + 1;
	}
}

TORRENT_TEST(event_completed)
{
	using sim::asio::ip::address_v4;
	sim::default_config network_cfg;
	sim::simulation sim{network_cfg};

	sim::asio::io_service web_server(sim, address_v4::from_string("2.2.2.2"));
	// listen on port 8080
	sim::http_server http(web_server, 8080);

	// the request strings of all announces
	std::vector<std::pair<int, std::string>> announces;

	const int interval = 500;
	lt::time_point start = lt::clock_type::now();

	http.register_handler("/announce"
	, [&](std::string method, std::string req
		, std::map<std::string, std::string>&)
	{
		TEST_EQUAL(method, "GET");
		int timestamp = chrono::duration_cast<lt::seconds>(
			lt::clock_type::now() - start).count();
		announces.push_back({timestamp, req});

		char response[500];
		int size = snprintf(response, sizeof(response), "d8:intervali%de5:peers0:e", interval);
		return sim::send_response(200, "OK", size) + response;
	});

	lt::settings_pack default_settings = settings();
	lt::add_torrent_params default_add_torrent;

	int completion = -1;

	setup_swarm(2, swarm_test::download, sim, default_settings, default_add_torrent
		// add session
		, [](lt::settings_pack& pack) { }
		// add torrent
		, [](lt::add_torrent_params& params) {
			params.trackers.push_back("http://2.2.2.2:8080/announce");
		}
		// on alert
		, [&](lt::alert const* a, lt::session& ses) {}
		// terminate
		, [&](int ticks, lt::session& ses) -> bool
		{
			if (completion == -1 && is_seed(ses))
			{
				completion = chrono::duration_cast<lt::seconds>(
					lt::clock_type::now() - start).count();
			}

			return ticks > duration;
		});

	// the first announce should be event=started, the second should be
	// event=completed, then all but the last should have no event and the last
	// be event=stopped.
	for (int i = 0; i < int(announces.size()); ++i)
	{
		std::string const& str = announces[i].second;
		int timestamp = announces[i].first;

		const bool has_start = str.find("&event=started")
			!= std::string::npos;
		const bool has_completed = str.find("&event=completed")
			!= std::string::npos;
		const bool has_stopped = str.find("&event=stopped")
			!= std::string::npos;

		// we there can only be one event
		const bool has_event = str.find("&event=") != std::string::npos;

		fprintf(stderr, "- %s\n", str.c_str());

		// there is exactly 0 or 1 events.
		TEST_EQUAL(int(has_start) + int(has_completed) + int(has_stopped)
			, int(has_event));

		switch (i)
		{
			case 0:
				TEST_CHECK(has_start);
				break;
			case 1:
			{
				// the announce should have come approximately the same time we
				// completed
				TEST_CHECK(abs(completion - timestamp) <= 1);
				TEST_CHECK(has_completed);
				break;
			}
			default:
				if (i == int(announces.size()) - 1)
				{
					TEST_CHECK(has_stopped);
				}
				else
				{
					TEST_CHECK(!has_event);
				}
				break;
		}
	}
}

TORRENT_TEST(announce_interval_440)
{
	test_interval(440);
}

TORRENT_TEST(announce_interval_1800)
{
	test_interval(1800);
}

TORRENT_TEST(announce_interval_1200)
{
	test_interval(3600);
}

struct sim_config : sim::default_config
{
	chrono::high_resolution_clock::duration hostname_lookup(
		asio::ip::address const& requestor
		, std::string hostname
		, std::vector<asio::ip::address>& result
		, boost::system::error_code& ec)
	{
		if (hostname == "tracker.com")
		{
			result.push_back(address_v4::from_string("10.0.0.2"));
			result.push_back(address_v6::from_string("ff::dead:beef"));
			return duration_cast<chrono::high_resolution_clock::duration>(chrono::milliseconds(100));
		}

		return default_config::hostname_lookup(requestor, hostname, result, ec);
	}
};

void on_alert_notify(lt::session* ses)
{
	ses->get_io_service().post([ses] {
		std::vector<lt::alert*> alerts;
		ses->pop_alerts(&alerts);

		for (lt::alert* a : alerts)
		{
			lt::time_duration d = a->timestamp().time_since_epoch();
			boost::uint32_t millis = lt::duration_cast<lt::milliseconds>(d).count();
			printf("%4d.%03d: %s\n", millis / 1000, millis % 1000,
				a->message().c_str());
		}
	});
}

// this test makes sure that a tracker whose host name resolves to both IPv6 and
// IPv4 addresses will be announced to twice, once for each address family
TORRENT_TEST(ipv6_support)
{
	using sim::asio::ip::address_v4;
	sim_config network_cfg;
	sim::simulation sim{network_cfg};

	sim::asio::io_service web_server_v4(sim, address_v4::from_string("10.0.0.2"));
	sim::asio::io_service web_server_v6(sim, address_v6::from_string("ff::dead:beef"));

	// listen on port 8080
	sim::http_server http_v4(web_server_v4, 8080);
	sim::http_server http_v6(web_server_v6, 8080);

	int v4_announces = 0;
	int v6_announces = 0;

	http_v4.register_handler("/announce"
	, [&v4_announces](std::string method, std::string req
		, std::map<std::string, std::string>&)
	{
		++v4_announces;
		TEST_EQUAL(method, "GET");

		char response[500];
		int size = snprintf(response, sizeof(response), "d8:intervali1800e5:peers0:e");
		return sim::send_response(200, "OK", size) + response;
	});

	http_v6.register_handler("/announce"
	, [&v6_announces](std::string method, std::string req
		, std::map<std::string, std::string>&)
	{
		++v6_announces;
		TEST_EQUAL(method, "GET");

		char response[500];
		int size = snprintf(response, sizeof(response), "d8:intervali1800e5:peers0:e");
		return sim::send_response(200, "OK", size) + response;
	});

	{
		lt::session_proxy zombie;

		asio::io_service ios(sim, { address_v4::from_string("10.0.0.3")
			, address_v6::from_string("ffff::1337") });
		lt::settings_pack sett = settings();
		std::unique_ptr<lt::session> ses(new lt::session(sett, ios));

		ses->set_alert_notify(std::bind(&on_alert_notify, ses.get()));


		lt::add_torrent_params p;
		p.name = "test-torrent";
		p.save_path = ".";
		p.info_hash.assign("abababababababababab");

//TODO: parameterize http vs. udp here
		p.trackers.push_back("http://tracker.com:8080/announce");
		ses->async_add_torrent(p);

		// stop the torrent 5 seconds in
		asio::high_resolution_timer stop(ios);
		stop.expires_from_now(chrono::seconds(5));
		stop.async_wait([&ses](boost::system::error_code const& ec)
		{
			std::vector<lt::torrent_handle> torrents = ses->get_torrents();
			for (auto const& t : torrents)
			{
				t.pause();
			}
		});

		// then shut down 10 seconds in
		asio::high_resolution_timer terminate(ios);
		terminate.expires_from_now(chrono::seconds(10));
		terminate.async_wait([&ses,&zombie](boost::system::error_code const& ec)
		{
			zombie = ses->abort();
			ses->set_alert_notify([]{});
			ses.reset();
		});

		sim.run();
	}

	// 2 because there's one announce on startup and one when shutting down
	TEST_EQUAL(v4_announces, 2);
	TEST_EQUAL(v6_announces, 2);
}

template <typename Announce, typename Test1, typename Test2>
void tracker_test(Announce a, Test1 test1, Test2 test2, char const* url_path = "/announce")
{
	using sim::asio::ip::address_v4;
	sim_config network_cfg;
	sim::simulation sim{network_cfg};

	sim::asio::io_service tracker_ios(sim, address_v4::from_string("10.0.0.2"));

	// listen on port 8080
	sim::http_server http(tracker_ios, 8080);

	http.register_handler(url_path, a);

	lt::session_proxy zombie;

	asio::io_service ios(sim, { address_v4::from_string("10.0.0.3")
		, address_v6::from_string("ffff::1337") });
	lt::settings_pack sett = settings();
	std::unique_ptr<lt::session> ses(new lt::session(sett, ios));

	ses->set_alert_notify(std::bind(&on_alert_notify, ses.get()));

	lt::add_torrent_params p;
	p.name = "test-torrent";
	p.save_path = ".";
	p.info_hash.assign("abababababababababab");
	p.trackers.push_back("http://tracker.com:8080/announce");
	ses->async_add_torrent(p);

	// run the test 5 seconds in
	asio::high_resolution_timer t1(ios);
	t1.expires_from_now(chrono::seconds(5));
	t1.async_wait([&ses,&test1](boost::system::error_code const& ec)
	{
		std::vector<lt::torrent_handle> torrents = ses->get_torrents();
		TEST_EQUAL(torrents.size(), 1);
		torrent_handle h = torrents.front();
		test1(h);
	});

	asio::high_resolution_timer t2(ios);
	t2.expires_from_now(chrono::seconds(9));
	t2.async_wait([&ses,&test2](boost::system::error_code const& ec)
	{
		std::vector<lt::torrent_handle> torrents = ses->get_torrents();
		TEST_EQUAL(torrents.size(), 1);
		torrent_handle h = torrents.front();
		test2(h);
	});

	// then shut down 10 seconds in
	asio::high_resolution_timer t3(ios);
	t3.expires_from_now(chrono::seconds(10));
	t3.async_wait([&ses,&zombie](boost::system::error_code const& ec)
	{
		zombie = ses->abort();
		ses->set_alert_notify([]{});
		ses.reset();
	});

	sim.run();
}

template <typename Announce, typename Test>
void announce_entry_test(Announce a, Test t, char const* url_path = "/announce")
{
	tracker_test(a
		, [&t] (torrent_handle h) {
			std::vector<announce_entry> tr = h.trackers();

			TEST_EQUAL(tr.size(), 1);
			announce_entry const& ae = tr[0];
			t(ae);
		}
		, [](torrent_handle){}
		, url_path);
}

TORRENT_TEST(test_error)
{
	announce_entry_test(
		[](std::string method, std::string req
			, std::map<std::string, std::string>& headers)
		{
			TEST_EQUAL(method, "GET");

			char response[500];
			int size = snprintf(response, sizeof(response), "d14:failure reason4:teste");
			return sim::send_response(200, "OK", size) + response;
		}
		, [](announce_entry const& ae)
		{
			TEST_EQUAL(ae.is_working(), false);
			TEST_EQUAL(ae.message, "test");
			TEST_EQUAL(ae.url, "http://tracker.com:8080/announce");
			TEST_EQUAL(ae.last_error, error_code(errors::tracker_failure
				, get_libtorrent_category()));
			TEST_EQUAL(ae.fails, 1);
		});
}

TORRENT_TEST(test_warning)
{
	announce_entry_test(
		[](std::string method, std::string req
			, std::map<std::string, std::string>& headers)
		{
			TEST_EQUAL(method, "GET");

			char response[500];
			int size = snprintf(response, sizeof(response), "d5:peers6:aaaaaa15:warning message5:test2e");
			return sim::send_response(200, "OK", size) + response;
		}
		, [](announce_entry const& ae)
		{
			TEST_EQUAL(ae.is_working(), true);
			TEST_EQUAL(ae.message, "test2");
			TEST_EQUAL(ae.url, "http://tracker.com:8080/announce");
			TEST_EQUAL(ae.last_error, error_code());
			TEST_EQUAL(ae.fails, 0);
		});
}

TORRENT_TEST(test_scrape_data_in_announce)
{
	announce_entry_test(
		[](std::string method, std::string req
			, std::map<std::string, std::string>& headers)
		{
			TEST_EQUAL(method, "GET");

			char response[500];
			int size = snprintf(response, sizeof(response),
				"d5:peers6:aaaaaa8:completei1e10:incompletei2e10:downloadedi3e11:downloadersi4ee");
			return sim::send_response(200, "OK", size) + response;
		}
		, [](announce_entry const& ae)
		{
			TEST_EQUAL(ae.is_working(), true);
			TEST_EQUAL(ae.message, "");
			TEST_EQUAL(ae.url, "http://tracker.com:8080/announce");
			TEST_EQUAL(ae.last_error, error_code());
			TEST_EQUAL(ae.fails, 0);
			TEST_EQUAL(ae.scrape_complete, 1);
			TEST_EQUAL(ae.scrape_incomplete, 2);
			TEST_EQUAL(ae.scrape_downloaded, 3);
		});
}

TORRENT_TEST(test_scrape)
{
	tracker_test(
		[](std::string method, std::string req
			, std::map<std::string, std::string>& headers)
		{
			TEST_EQUAL(method, "GET");

			char response[500];
			int size = snprintf(response, sizeof(response),
				"d5:filesd20:ababababababababababd8:completei1e10:downloadedi3e10:incompletei2eeee");
			return sim::send_response(200, "OK", size) + response;
		}
		, [](torrent_handle h)
		{
			h.scrape_tracker();
		}
		, [](torrent_handle h)
		{
			std::vector<announce_entry> tr = h.trackers();

			TEST_EQUAL(tr.size(), 1);
			announce_entry const& ae = tr[0];
			TEST_EQUAL(ae.scrape_incomplete, 2);
			TEST_EQUAL(ae.scrape_complete, 1);
			TEST_EQUAL(ae.scrape_downloaded, 3);
		}
		, "/scrape");
}

TORRENT_TEST(test_http_status)
{
	announce_entry_test(
		[](std::string method, std::string req
			, std::map<std::string, std::string>& headers)
		{
			TEST_EQUAL(method, "GET");
			return sim::send_response(410, "Not A Tracker", 0);
		}
		, [](announce_entry const& ae)
		{
			TEST_EQUAL(ae.is_working(), false);
			TEST_EQUAL(ae.message, "Not A Tracker");
			TEST_EQUAL(ae.url, "http://tracker.com:8080/announce");
			TEST_EQUAL(ae.last_error, error_code(410, get_http_category()));
			TEST_EQUAL(ae.fails, 1);
		});
}

TORRENT_TEST(test_interval)
{
	announce_entry_test(
		[](std::string method, std::string req
			, std::map<std::string, std::string>& headers)
		{
			TEST_EQUAL(method, "GET");
			char response[500];
			int size = snprintf(response, sizeof(response)
				, "d10:tracker id8:testteste");
			return sim::send_response(200, "OK", size) + response;
		}
		, [](announce_entry const& ae)
		{
			TEST_EQUAL(ae.is_working(), true);
			TEST_EQUAL(ae.message, "");
			TEST_EQUAL(ae.url, "http://tracker.com:8080/announce");
			TEST_EQUAL(ae.last_error, error_code());
			TEST_EQUAL(ae.fails, 0);

			TEST_EQUAL(ae.trackerid, "testtest");
		});
}

TORRENT_TEST(test_invalid_bencoding)
{
	announce_entry_test(
		[](std::string method, std::string req
			, std::map<std::string, std::string>& headers)
		{
			TEST_EQUAL(method, "GET");
			char response[500];
			int size = snprintf(response, sizeof(response)
				, "d10:tracer idteste");
			return sim::send_response(200, "OK", size) + response;
		}
		, [](announce_entry const& ae)
		{
			TEST_EQUAL(ae.is_working(), false);
			TEST_EQUAL(ae.message, "");
			TEST_EQUAL(ae.url, "http://tracker.com:8080/announce");
			TEST_EQUAL(ae.last_error, error_code(bdecode_errors::expected_value
				, get_bdecode_category()));
			TEST_EQUAL(ae.fails, 1);
		});
}

// TODO: test external IP
// TODO: test with different queuing settings
// TODO: test when a torrent transitions from downloading to finished and
// finished to seeding
// TODO: test that left, downloaded and uploaded are reported correctly

// TODO: test scrape