#include <stdio.h>

#include <chrono>
#include <memory>

#include "aos/common/util/phased_loop.h"
#include "aos/common/time.h"
#include "aos/common/util/trapezoid_profile.h"
#include "aos/common/logging/logging.h"
#include "aos/common/logging/queue_logging.h"
#include "aos/common/actions/actions.h"

#include "frc971/autonomous/auto.q.h"
#include "frc971/control_loops/drivetrain/drivetrain.q.h"
#include "y2014/actors/drivetrain_actor.h"
#include "y2014/actors/shoot_actor.h"
#include "y2014/constants.h"
#include "y2014/control_loops/claw/claw.q.h"
#include "y2014/control_loops/drivetrain/drivetrain_dog_motor_plant.h"
#include "y2014/control_loops/shooter/shooter.q.h"
#include "y2014/queues/auto_mode.q.h"

#include "y2014/queues/hot_goal.q.h"
#include "y2014/queues/profile_params.q.h"

namespace y2014 {
namespace autonomous {
namespace chrono = ::std::chrono;
namespace this_thread = ::std::this_thread;
using ::aos::monotonic_clock;

namespace {

double DoubleSeconds(monotonic_clock::duration duration) {
  return ::std::chrono::duration_cast<::std::chrono::duration<double>>(duration)
      .count();
}

}  // namespace

static double left_initial_position, right_initial_position;

bool ShouldExitAuto() {
  ::frc971::autonomous::autonomous.FetchLatest();
  bool ans = !::frc971::autonomous::autonomous->run_auto;
  if (ans) {
    LOG(INFO, "Time to exit auto mode\n");
  }
  return ans;
}

void StopDrivetrain() {
  LOG(INFO, "Stopping the drivetrain\n");
  frc971::control_loops::drivetrain_queue.goal.MakeWithBuilder()
      .control_loop_driving(true)
      .highgear(true)
      .left_goal(left_initial_position)
      .left_velocity_goal(0)
      .right_goal(right_initial_position)
      .right_velocity_goal(0)
      .quickturn(false)
      .Send();
}

void ResetDrivetrain() {
  LOG(INFO, "resetting the drivetrain\n");
  ::frc971::control_loops::drivetrain_queue.goal.MakeWithBuilder()
      .control_loop_driving(false)
      .highgear(true)
      .wheel(0.0)
      .throttle(0.0)
      .left_goal(left_initial_position)
      .left_velocity_goal(0)
      .right_goal(right_initial_position)
      .right_velocity_goal(0)
      .Send();
}

void WaitUntilDoneOrCanceled(
    ::std::unique_ptr<aos::common::actions::Action> action) {
  if (!action) {
    LOG(ERROR, "No action, not waiting\n");
    return;
  }
  ::aos::time::PhasedLoop phased_loop(::std::chrono::milliseconds(10),
                                      ::std::chrono::milliseconds(10) / 2);
  while (true) {
    // Poll the running bit and auto done bits.
    phased_loop.SleepUntilNext();
    if (!action->Running() || ShouldExitAuto()) {
      return;
    }
  }
}

void StepDrive(double distance, double theta) {
  double left_goal = (left_initial_position + distance -
                      theta * control_loops::drivetrain::kRobotRadius);
  double right_goal = (right_initial_position + distance +
                       theta * control_loops::drivetrain::kRobotRadius);
  ::frc971::control_loops::drivetrain_queue.goal.MakeWithBuilder()
      .control_loop_driving(true)
      .highgear(true)
      .left_goal(left_goal)
      .right_goal(right_goal)
      .left_velocity_goal(0.0)
      .right_velocity_goal(0.0)
      .Send();
  left_initial_position = left_goal;
  right_initial_position = right_goal;
}

void PositionClawVertically(double intake_power = 0.0, double centering_power = 0.0) {
  if (!control_loops::claw_queue.goal.MakeWithBuilder()
           .bottom_angle(0.0)
           .separation_angle(0.0)
           .intake(intake_power)
           .centering(centering_power)
           .Send()) {
    LOG(WARNING, "sending claw goal failed\n");
  }
}

void PositionClawBackIntake() {
  if (!control_loops::claw_queue.goal.MakeWithBuilder()
           .bottom_angle(-2.273474)
           .separation_angle(0.0)
           .intake(12.0)
           .centering(12.0)
           .Send()) {
    LOG(WARNING, "sending claw goal failed\n");
  }
}

void PositionClawUpClosed() {
  // Move the claw to where we're going to shoot from but keep it closed until
  // it gets there.
  if (!control_loops::claw_queue.goal.MakeWithBuilder()
           .bottom_angle(0.86)
           .separation_angle(0.0)
           .intake(4.0)
           .centering(1.0)
           .Send()) {
    LOG(WARNING, "sending claw goal failed\n");
  }
}

void PositionClawForShot() {
  if (!control_loops::claw_queue.goal.MakeWithBuilder()
           .bottom_angle(0.86)
           .separation_angle(0.10)
           .intake(4.0)
           .centering(1.0)
           .Send()) {
    LOG(WARNING, "sending claw goal failed\n");
  }
}

void SetShotPower(double power) {
  LOG(INFO, "Setting shot power to %f\n", power);
  if (!control_loops::shooter_queue.goal.MakeWithBuilder()
           .shot_power(power)
           .shot_requested(false)
           .unload_requested(false)
           .load_requested(false)
           .Send()) {
    LOG(WARNING, "sending shooter goal failed\n");
  }
}

void WaitUntilNear(double distance) {
  while (true) {
    if (ShouldExitAuto()) return;
    ::frc971::control_loops::drivetrain_queue.status.FetchAnother();
    double left_error = ::std::abs(
        left_initial_position -
        ::frc971::control_loops::drivetrain_queue.status->estimated_left_position);
    double right_error = ::std::abs(
        right_initial_position -
        ::frc971::control_loops::drivetrain_queue.status->estimated_right_position);
    const double kPositionThreshold = 0.05 + distance;
    if (right_error < kPositionThreshold && left_error < kPositionThreshold) {
      LOG(INFO, "At the goal\n");
      return;
    }
  }
}

const ProfileParams kFastDrive = {3.0, 2.5};
const ProfileParams kSlowDrive = {2.5, 2.5};
const ProfileParams kFastWithBallDrive = {3.0, 2.0};
const ProfileParams kSlowWithBallDrive = {2.5, 2.0};
const ProfileParams kFastTurn = {3.0, 10.0};

::std::unique_ptr<::y2014::actors::DrivetrainAction> SetDriveGoal(
    double distance, const ProfileParams drive_params, double theta = 0,
    const ProfileParams &turn_params = kFastTurn) {
  LOG(INFO, "Driving to %f\n", distance);

  ::y2014::actors::DrivetrainActionParams params;
  params.left_initial_position = left_initial_position;
  params.right_initial_position = right_initial_position;
  params.y_offset = distance;
  params.theta_offset = theta;
  params.maximum_turn_acceleration = turn_params.acceleration;
  params.maximum_turn_velocity = turn_params.velocity;
  params.maximum_velocity = drive_params.velocity;
  params.maximum_acceleration = drive_params.acceleration;
  auto drivetrain_action = actors::MakeDrivetrainAction(params);
  drivetrain_action->Start();
  left_initial_position +=
      distance - theta * control_loops::drivetrain::kRobotRadius;
  right_initial_position +=
      distance + theta * control_loops::drivetrain::kRobotRadius;
  return drivetrain_action;
}

void Shoot() {
  // Shoot.
  auto shoot_action = actors::MakeShootAction();
  shoot_action->Start();
  WaitUntilDoneOrCanceled(::std::move(shoot_action));
}

void InitializeEncoders() {
  ::frc971::control_loops::drivetrain_queue.status.FetchAnother();
  left_initial_position =
      ::frc971::control_loops::drivetrain_queue.status->estimated_left_position;
  right_initial_position =
      ::frc971::control_loops::drivetrain_queue.status->estimated_right_position;
}

void WaitUntilClawDone() {
  while (true) {
    ::aos::time::PhasedLoop phased_loop(::std::chrono::milliseconds(10),
                                        ::std::chrono::milliseconds(10) / 2);
    // Poll the running bit and auto done bits.
    phased_loop.SleepUntilNext();
    control_loops::claw_queue.status.FetchLatest();
    control_loops::claw_queue.goal.FetchLatest();
    if (ShouldExitAuto()) {
      return;
    }
    if (control_loops::claw_queue.status.get() == nullptr ||
        control_loops::claw_queue.goal.get() == nullptr) {
      continue;
    }
    bool ans =
        control_loops::claw_queue.status->zeroed &&
        (::std::abs(control_loops::claw_queue.status->bottom_velocity) <
         1.0) &&
        (::std::abs(control_loops::claw_queue.status->bottom -
                    control_loops::claw_queue.goal->bottom_angle) <
         0.10) &&
        (::std::abs(control_loops::claw_queue.status->separation -
                    control_loops::claw_queue.goal->separation_angle) <
         0.4);
    if (ans) {
      return;
    }
    if (ShouldExitAuto()) return;
  }
}

class HotGoalDecoder {
 public:
  HotGoalDecoder() {
    ResetCounts();
  }

  void ResetCounts() {
    hot_goal.FetchLatest();
    if (hot_goal.get()) {
      start_counts_ = *hot_goal;
      LOG_STRUCT(INFO, "counts reset to", start_counts_);
      start_counts_valid_ = true;
    } else {
      LOG(WARNING, "no hot goal message. ignoring\n");
      start_counts_valid_ = false;
    }
  }

  void Update(bool block = false) {
    if (block) {
      hot_goal.FetchAnother();
    } else {
      hot_goal.FetchLatest();
    }
    if (hot_goal.get()) LOG_STRUCT(INFO, "new counts", *hot_goal);
  }

  bool left_triggered() const {
    if (!start_counts_valid_ || !hot_goal.get()) return false;
    return (hot_goal->left_count - start_counts_.left_count) > kThreshold;
  }

  bool right_triggered() const {
    if (!start_counts_valid_ || !hot_goal.get()) return false;
    return (hot_goal->right_count - start_counts_.right_count) > kThreshold;
  }

  bool is_left() const {
    if (!start_counts_valid_ || !hot_goal.get()) return false;
    const uint64_t left_difference =
        hot_goal->left_count - start_counts_.left_count;
    const uint64_t right_difference =
        hot_goal->right_count - start_counts_.right_count;
    if (left_difference > kThreshold) {
      if (right_difference > kThreshold) {
        // We've seen a lot of both, so pick the one we've seen the most of.
        return left_difference > right_difference;
      } else {
        // We've seen enough left but not enough right, so go with it.
        return true;
      }
    } else {
      // We haven't seen enough left, so it's not left.
      return false;
    }
  }

  bool is_right() const {
    if (!start_counts_valid_ || !hot_goal.get()) return false;
    const uint64_t left_difference =
        hot_goal->left_count - start_counts_.left_count;
    const uint64_t right_difference =
        hot_goal->right_count - start_counts_.right_count;
    if (right_difference > kThreshold) {
      if (left_difference > kThreshold) {
        // We've seen a lot of both, so pick the one we've seen the most of.
        return right_difference > left_difference;
      } else {
        // We've seen enough right but not enough left, so go with it.
        return true;
      }
    } else {
      // We haven't seen enough right, so it's not right.
      return false;
    }
  }

 private:
  static const uint64_t kThreshold = 5;

  ::y2014::HotGoal start_counts_;
  bool start_counts_valid_;
};

void HandleAuto() {
  enum class AutoVersion : uint8_t {
    kStraight,
    kDoubleHot,
    kSingleHot,
  };

  // The front of the robot is 1.854 meters from the wall
  static const double kShootDistance = 3.15;
  static const double kPickupDistance = 0.5;
  static const double kTurnAngle = 0.3;

  monotonic_clock::time_point start_time = monotonic_clock::now();
  LOG(INFO, "Handling auto mode\n");

  AutoVersion auto_version;
  ::y2014::sensors::auto_mode.FetchLatest();
  if (!::y2014::sensors::auto_mode.get()) {
    LOG(WARNING, "not sure which auto mode to use\n");
    auto_version = AutoVersion::kStraight;
  } else {
    static const double kSelectorMin = 0.2, kSelectorMax = 4.4;

    const double kSelectorStep = (kSelectorMax - kSelectorMin) / 3.0;
    if (::y2014::sensors::auto_mode->voltage < kSelectorStep + kSelectorMin) {
      auto_version = AutoVersion::kSingleHot;
    } else if (::y2014::sensors::auto_mode->voltage <
               2 * kSelectorStep + kSelectorMin) {
      auto_version = AutoVersion::kStraight;
    } else {
      auto_version = AutoVersion::kDoubleHot;
    }
  }
  LOG(INFO, "running auto %" PRIu8 "\n", static_cast<uint8_t>(auto_version));

  const ProfileParams &drive_params =
      (auto_version == AutoVersion::kStraight) ? kFastDrive : kSlowDrive;
  const ProfileParams &drive_with_ball_params =
      (auto_version == AutoVersion::kStraight) ? kFastWithBallDrive
                                               : kSlowWithBallDrive;

  HotGoalDecoder hot_goal_decoder;
  // True for left, false for right.
  bool first_shot_left, second_shot_left_default, second_shot_left;

  ResetDrivetrain();

  this_thread::sleep_for(chrono::milliseconds(100));
  if (ShouldExitAuto()) return;
  InitializeEncoders();

  // Turn the claw on, keep it straight up until the ball has been grabbed.
  LOG(INFO, "Claw going up at %f\n",
      DoubleSeconds(monotonic_clock::now() - start_time));
  PositionClawVertically(12.0, 4.0);
  SetShotPower(115.0);

  // Wait for the ball to enter the claw.
  this_thread::sleep_for(chrono::milliseconds(250));
  if (ShouldExitAuto()) return;
  LOG(INFO, "Readying claw for shot at %f\n",
      DoubleSeconds(monotonic_clock::now() - start_time));

  {
    if (ShouldExitAuto()) return;
    // Drive to the goal.
    auto drivetrain_action = SetDriveGoal(-kShootDistance, drive_params);
    this_thread::sleep_for(chrono::milliseconds(750));
    PositionClawForShot();
    LOG(INFO, "Waiting until drivetrain is finished\n");
    WaitUntilDoneOrCanceled(::std::move(drivetrain_action));
    if (ShouldExitAuto()) return;
  }

  hot_goal_decoder.Update();
  if (hot_goal_decoder.is_left()) {
    LOG(INFO, "first shot left\n");
    first_shot_left = true;
    second_shot_left_default = false;
  } else if (hot_goal_decoder.is_right()) {
    LOG(INFO, "first shot right\n");
    first_shot_left = false;
    second_shot_left_default = true;
  } else {
    LOG(INFO, "first shot defaulting left\n");
    first_shot_left = true;
    second_shot_left_default = true;
  }
  if (auto_version == AutoVersion::kDoubleHot) {
    if (ShouldExitAuto()) return;
    auto drivetrain_action = SetDriveGoal(
        0, drive_with_ball_params, first_shot_left ? kTurnAngle : -kTurnAngle);
    WaitUntilDoneOrCanceled(::std::move(drivetrain_action));
    if (ShouldExitAuto()) return;
  } else if (auto_version == AutoVersion::kSingleHot) {
    do {
      // TODO(brians): Wait for next message with timeout or something.
      this_thread::sleep_for(chrono::milliseconds(3));
      hot_goal_decoder.Update(false);
      if (ShouldExitAuto()) return;
    } while (!hot_goal_decoder.left_triggered() &&
             (monotonic_clock::now() - start_time) < chrono::seconds(9));
  } else if (auto_version == AutoVersion::kStraight) {
    this_thread::sleep_for(chrono::milliseconds(400));
  }

  // Shoot.
  LOG(INFO, "Shooting at %f\n",
      DoubleSeconds(monotonic_clock::now() - start_time));
  Shoot();
  this_thread::sleep_for(chrono::milliseconds(50));

  if (auto_version == AutoVersion::kDoubleHot) {
    if (ShouldExitAuto()) return;
    auto drivetrain_action = SetDriveGoal(
        0, drive_with_ball_params, first_shot_left ? -kTurnAngle : kTurnAngle);
    WaitUntilDoneOrCanceled(::std::move(drivetrain_action));
    if (ShouldExitAuto()) return;
  } else if (auto_version == AutoVersion::kSingleHot) {
    LOG(INFO, "auto done at %f\n",
        DoubleSeconds(monotonic_clock::now() - start_time));
    PositionClawVertically(0.0, 0.0);
    return;
  }

  {
    if (ShouldExitAuto()) return;
    // Intake the new ball.
    LOG(INFO, "Claw ready for intake at %f\n",
        DoubleSeconds(monotonic_clock::now() - start_time));
    PositionClawBackIntake();
    auto drivetrain_action =
        SetDriveGoal(kShootDistance + kPickupDistance, drive_params);
    LOG(INFO, "Waiting until drivetrain is finished\n");
    WaitUntilDoneOrCanceled(::std::move(drivetrain_action));
    if (ShouldExitAuto()) return;
    LOG(INFO, "Wait for the claw at %f\n",
        DoubleSeconds(monotonic_clock::now() - start_time));
    WaitUntilClawDone();
    if (ShouldExitAuto()) return;
  }

  // Drive back.
  {
    LOG(INFO, "Driving back at %f\n",
        DoubleSeconds(monotonic_clock::now() - start_time));
    auto drivetrain_action =
        SetDriveGoal(-(kShootDistance + kPickupDistance), drive_params);
    this_thread::sleep_for(chrono::milliseconds(300));
    hot_goal_decoder.ResetCounts();
    if (ShouldExitAuto()) return;
    PositionClawUpClosed();
    WaitUntilClawDone();
    if (ShouldExitAuto()) return;
    PositionClawForShot();
    LOG(INFO, "Waiting until drivetrain is finished\n");
    WaitUntilDoneOrCanceled(::std::move(drivetrain_action));
    if (ShouldExitAuto()) return;
    WaitUntilClawDone();
    if (ShouldExitAuto()) return;
  }

  hot_goal_decoder.Update();
  if (hot_goal_decoder.is_left()) {
    LOG(INFO, "second shot left\n");
    second_shot_left = true;
  } else if (hot_goal_decoder.is_right()) {
    LOG(INFO, "second shot right\n");
    second_shot_left = false;
  } else {
    LOG(INFO, "second shot defaulting %s\n",
        second_shot_left_default ? "left" : "right");
    second_shot_left = second_shot_left_default;
  }
  if (auto_version == AutoVersion::kDoubleHot) {
    if (ShouldExitAuto()) return;
    auto drivetrain_action = SetDriveGoal(
        0, drive_params, second_shot_left ? kTurnAngle : -kTurnAngle);
    WaitUntilDoneOrCanceled(::std::move(drivetrain_action));
    if (ShouldExitAuto()) return;
  } else if (auto_version == AutoVersion::kStraight) {
    this_thread::sleep_for(chrono::milliseconds(400));
  }

  LOG(INFO, "Shooting at %f\n",
      DoubleSeconds(monotonic_clock::now() - start_time));
  // Shoot
  Shoot();
  if (ShouldExitAuto()) return;

  // Get ready to zero when we come back up.
  this_thread::sleep_for(chrono::milliseconds(50));
  PositionClawVertically(0.0, 0.0);
}

}  // namespace autonomous
}  // namespace y2014