#include <boost/test/unit_test.hpp>

#include <chrono>
#include <cstdint>
#include <string>
#include <vector>

#include <boost/asio/io_context.hpp>
#include <boost/asio/post.hpp>

#include <vamp_protocol/gesture.hpp>
#include <vamp_zero/touch_input.hpp>


namespace {

auto touch_event(luma::touch_phase phase, std::chrono::steady_clock::time_point time, std::int32_t id = 1) -> luma::touch_event {
  return {.points = {{.id = id, .phase = phase}}, .time = time};
}

struct touch_sample {
  std::bool_t pressed;
  std::uint64_t milliseconds;
};

}

BOOST_AUTO_TEST_CASE(zero_and_pico_share_timestamped_gesture_transitions) {
  auto sequences = std::vector<std::vector<touch_sample>>{
    {{true, 0}, {false, 30}},
    {{true, 0}, {false, 30}, {true, 200}, {false, 300}},
    {{true, 0}, {false, 40}, {true, 180}, {false, 260}},
    {{true, 0}, {false, 40}, {true, 180}, {false, 261}},
    {{true, 0}, {false, 40}, {true, 261}, {false, 300}},
    {{true, 50}, {true, 749}, {true, 750}, {true, 900}, {false, 910}},
    {{true, 0}, {false, 40}, {true, 180}, {false, 880}},
    {{true, 0}, {false, 699}},
    {{true, 0}, {false, 700}},
  };
  auto expected = std::vector<std::vector<std::string>>{
    {"next"},
    {"next", "next"},
    {"previous"},
    {"next", "next"},
    {"next", "next"},
    {"select"},
    {"select"},
    {"next"},
    {"select"},
  };
  for (auto index = std::size_t{}; index < sequences.size(); ++index) {
    auto io = boost::asio::io_context{};
    auto zero_commands = std::vector<std::string>{};
    auto pico_commands = std::vector<std::string>{};
    auto zero = vamp_zero::touch_input{io.get_executor(), [&](auto command) { zero_commands.emplace_back(vamp_protocol::page_command_name(command)); }};
    auto pico = vamp_protocol::gesture_state{};
    auto base = std::chrono::steady_clock::now() - std::chrono::seconds{10};
    auto down = std::bool_t{false};
    for (auto sample : sequences[index]) {
      auto phase = sample.pressed ? (down ? luma::touch_phase::MOVE : luma::touch_phase::DOWN) : luma::touch_phase::UP;
      BOOST_TEST(zero.handle(touch_event(phase, base + std::chrono::milliseconds{sample.milliseconds})));
      if (auto command = pico.update(sample.pressed, sample.milliseconds)) {
        pico_commands.emplace_back(vamp_protocol::page_command_name(*command));
      }
      down = sample.pressed;
    }
    if (auto command = pico.update(false, 2000U)) {
      pico_commands.emplace_back(vamp_protocol::page_command_name(*command));
    }
    io.run();
    BOOST_TEST(zero_commands == expected[index], boost::test_tools::per_element());
    BOOST_TEST(pico_commands == expected[index], boost::test_tools::per_element());
  }
}

BOOST_AUTO_TEST_CASE(shared_gesture_deadline_and_reset_discard_pending_actions) {
  auto gesture = vamp_protocol::gesture_state{};
  BOOST_TEST(!gesture.pending_deadline());
  BOOST_TEST(!gesture.update(true, 0U));
  BOOST_TEST(!gesture.update(false, 30U));
  BOOST_REQUIRE(gesture.pending_deadline());
  BOOST_TEST(*gesture.pending_deadline() == 251U);
  BOOST_TEST(!gesture.update(false, 250U));
  BOOST_TEST(!gesture.update(true, 250U));
  BOOST_TEST(!gesture.pending_deadline());
  gesture.reset();
  BOOST_TEST(!gesture.pending_deadline());
  BOOST_TEST(!gesture.update(false, 2000U));
}

BOOST_AUTO_TEST_CASE(zero_touch_timer_emits_a_single_tap_without_further_input) {
  auto io = boost::asio::io_context{};
  auto commands = std::vector<std::string>{};
  auto touch = vamp_zero::touch_input{io.get_executor(), [&](auto command) { commands.emplace_back(vamp_protocol::page_command_name(command)); }};
  auto now = std::chrono::steady_clock::now();
  touch.handle(touch_event(luma::touch_phase::DOWN, now));
  touch.handle(touch_event(luma::touch_phase::UP, now));
  io.poll();
  BOOST_TEST(commands.empty());
  io.run();
  BOOST_REQUIRE_EQUAL(commands.size(), 1U);
  BOOST_TEST(commands.front() == "next");
}

BOOST_AUTO_TEST_CASE(zero_touch_filters_other_fingers_and_cancels_pending_actions) {
  auto io = boost::asio::io_context{};
  auto commands = std::vector<std::string>{};
  auto touch = vamp_zero::touch_input{io.get_executor(), [&](auto command) { commands.emplace_back(vamp_protocol::page_command_name(command)); }};
  auto base = std::chrono::steady_clock::now() - std::chrono::seconds{10};
  BOOST_TEST(touch.handle(touch_event(luma::touch_phase::DOWN, base)));
  BOOST_TEST(!touch.handle(touch_event(luma::touch_phase::DOWN, base, 2)));
  BOOST_TEST(!touch.handle(touch_event(luma::touch_phase::UP, base, 2)));
  BOOST_TEST(touch.handle(touch_event(luma::touch_phase::UP, base + std::chrono::milliseconds{30})));
  BOOST_TEST(touch.handle(touch_event(luma::touch_phase::DOWN, base + std::chrono::milliseconds{200})));
  BOOST_TEST(touch.handle(touch_event(luma::touch_phase::CANCEL, base + std::chrono::milliseconds{210})));
  BOOST_TEST(!touch.handle(touch_event(luma::touch_phase::UP, base + std::chrono::milliseconds{220})));
  io.run();
  BOOST_TEST(commands.empty());
}

BOOST_AUTO_TEST_CASE(zero_touch_stale_timer_cannot_consume_newer_gesture) {
  auto io = boost::asio::io_context{};
  auto commands = std::vector<std::string>{};
  auto touch = vamp_zero::touch_input{io.get_executor(), [&](auto command) { commands.emplace_back(vamp_protocol::page_command_name(command)); }};
  auto base = std::chrono::steady_clock::now() - std::chrono::seconds{10};
  touch.handle(touch_event(luma::touch_phase::DOWN, base));
  touch.handle(touch_event(luma::touch_phase::UP, base + std::chrono::milliseconds{30}));
  boost::asio::post(io, [&] {
    touch.handle(touch_event(luma::touch_phase::DOWN, base + std::chrono::milliseconds{200}));
    touch.handle(touch_event(luma::touch_phase::UP, base + std::chrono::milliseconds{220}));
  });
  io.run();
  BOOST_REQUIRE_EQUAL(commands.size(), 1U);
  BOOST_TEST(commands.front() == "previous");
}

BOOST_AUTO_TEST_CASE(zero_touch_stop_and_destruction_suppress_queued_commands) {
  for (auto hold : {false, true}) {
    auto io = boost::asio::io_context{};
    auto commands = std::vector<std::string>{};
    {
      auto touch = vamp_zero::touch_input{io.get_executor(), [&](auto command) { commands.emplace_back(vamp_protocol::page_command_name(command)); }};
      auto base = std::chrono::steady_clock::now() - std::chrono::seconds{10};
      touch.handle(touch_event(luma::touch_phase::DOWN, base));
      touch.handle(touch_event(luma::touch_phase::UP, base + std::chrono::milliseconds{hold ? 700 : 30}));
      touch.stop();
      BOOST_TEST(!touch.handle(touch_event(luma::touch_phase::DOWN, base)));
    }
    io.run();
    BOOST_TEST(commands.empty());
  }
}

BOOST_AUTO_TEST_CASE(zero_touch_reset_discards_old_score_gestures_but_accepts_new_input) {
  auto io = boost::asio::io_context{};
  auto commands = std::vector<std::string>{};
  auto touch = vamp_zero::touch_input{io.get_executor(), [&](auto command) { commands.emplace_back(vamp_protocol::page_command_name(command)); }};
  auto base = std::chrono::steady_clock::now() - std::chrono::seconds{10};
  touch.handle(touch_event(luma::touch_phase::DOWN, base));
  touch.handle(touch_event(luma::touch_phase::UP, base + std::chrono::milliseconds{700}));
  touch.reset();
  io.run();
  BOOST_TEST(commands.empty());
  io.restart();
  touch.handle(touch_event(luma::touch_phase::DOWN, base));
  touch.handle(touch_event(luma::touch_phase::UP, base + std::chrono::milliseconds{30}));
  io.run();
  BOOST_REQUIRE_EQUAL(commands.size(), 1U);
  BOOST_TEST(commands.front() == "next");
}