using Godot;
using System;
using System.Collections.Generic;

public partial class LivingArmor : CharacterBody2D
{
	[Signal]
	public delegate void KilledEventHandler();
	public enum State
	{
		Waiting,
		Moving,
		Attack
	}

	public enum SideFace
	{
		Left,
		Up,
		Right,
		Down
	}

	[Export] public SideFace Facing = SideFace.Down;
	[Export] public float MovingSpeed = 16f;

	public State CurrentState
	{
		get => _state;

		private set
		{
			_state = value;
			_timeSinceState = 0;

			switch (_state)
			{
				case State.Waiting:
					break;
				case State.Moving:
					break;
				case State.Attack:
					break;
			}
		}
	}

	private State _state;
	private float _timeSinceState;
	private AnimatedSprite2D _sprite;
	private bool _isLitUp;
	//private readonly List<WeakRef> _bodiesInSight = new List<WeakRef>();
	private readonly List<Node2D> _bodiesInSight = new List<Node2D>();
	private readonly List<Node2D> _bodiesNearBy = new List<Node2D>();
	private Node2D _target = null;
	private Vector2 _respawnPosition;
	
	public override void _Ready()
	{
		_sprite = (AnimatedSprite2D)FindChild("AnimatedSprite2D");
		_respawnPosition = Position;
		CurrentState = State.Waiting;
		var animationName = "side_walk";
		switch (Facing)
		{
			case SideFace.Left:
				_sprite.FlipH = true;
				break;
			case SideFace.Right:
				break;
			case SideFace.Up:
				animationName = "up_walk";
				break;
			case SideFace.Down:
				animationName = "down_walk";
				break;
		}

		_sprite.Play(animationName);
		_sprite.Stop();
	}

	public override void _Process(double delta)
	{
	}

	public override void _PhysicsProcess(double delta)
	{
		_timeSinceState += (float)delta;

		switch (_state)
		{
			case State.Attack:
				break;
			case State.Waiting:
				_sprite.Pause();
				break;

			case State.Moving:
				foreach (var body in _bodiesNearBy)
				{
					switch (body)
					{
						case Wretched wretched:
							wretched.Kill(this);
							break;
						case Player player:
							player.Kill(this);
							break;
					}
				}
				SearchTarget();
				switch (_target)
				{
					case Player player:
						if (!player.Alive)
						{
							_bodiesInSight.Remove(player);
							_target = null;
						}
						break;
					case Wretched wretched:
						if (!wretched.IsAlive)
						{
							_bodiesInSight.Remove(wretched);
							_target = null;
						}
						break;
				}
				if (_target is null)
				{
					_state = State.Waiting;
					return;
				}
				var direction = (_target.Position - Position).Normalized();
				Velocity = direction * MovingSpeed;

				var animationName = "side_walk";

				if (Velocity.Y > 0.001f)
					animationName = "down_walk";
				else if (Velocity.Y < 0.001f)
					animationName = "up_walk";

				if (Mathf.Abs(Velocity.X) >= Mathf.Abs(Velocity.Y))
					animationName = "side_walk";

				_sprite.FlipH = Velocity.X < 0.001f && animationName == "side_walk";
				_sprite.Play(animationName);
				MoveAndSlide();
				//MoveAndCollide(direction);
				break;
		}

		CheckIfLitUp();
	}

	private void SearchTarget()
	{
		float targetDistance = -1;
		foreach (var body in _bodiesInSight)
		{
			var distance = (body.Position - Position).Length();
			GD.Print($"{body.Name}");
			switch (body)
			{
				case Wretched wretched:
					if (targetDistance < 0 || targetDistance > distance)
					{
						targetDistance = distance;
						_target = wretched;
					}
					break;
				case Player player:
					
					if (_target is Wretched)
					{
						continue;
					}
						
					_target = player;
					break;
			}
		}
	}
	
	private void _OnLightEntered(Area2D area)
	{
		if (area.GetParentOrNull<GameCamera>() is null)
			return;

		_isLitUp = true;
	}


	private void _OnPlayerCollision(Node2D body)
	{
		_bodiesNearBy.Add(body);
	}

	private void _OnLightExited(Area2D area)
	{
		if (area.GetParentOrNull<GameCamera>() is null)
			return;

		_isLitUp = false;
	}

	private void _OnPlayerCollisionExited(Node2D body)
	{
		_bodiesNearBy.Remove(body);
	}

	void CheckIfLitUp()
	{
		if (!_isLitUp)
		{
			CurrentState = State.Waiting;
			return;
		}

		if (CurrentState is State.Moving or State.Attack)
			return;
		CurrentState = State.Moving;
	}


	private void _OnBodyEntered(Node2D body)
	{
		if (body is not Wretched and not Player)
			return;
		
		_bodiesInSight.Add(body);	
	}


	private void _OnBodyExited(Node2D body)
	{
		if (body is not Wretched and not Player)
			return;
		if (body == _target)
		{
			_target = null;
		}
		_bodiesInSight.Remove(body);
	}
	
	public void Kill(Node2D killer)
	{
		GD.Print($"{this.Name} was killed by {killer.Name}");
		EmitSignal(SignalName.Killed);
		Position = _respawnPosition;
		// QueueFree(); // TODO
	}
}