GameJamDungeon/Zennysoft.Game.Ma/src/enemy/EnemyModelView2D.cs

using Chickensoft.AutoInject;
using Chickensoft.Introspection;
using Godot;
using System.Linq;
using Zennysoft.Ma.Adapter;

namespace Zennysoft.Game.Ma;
[Meta(typeof(IAutoNode))]
public partial class EnemyModelView2D : EnemyModelView, IEnemyModelView
{
  public override void _Notification(int what) => this.Notify(what);

  [Export] public EnemyLoreInfo EnemyLoreInfo { get; set; } = default!;

  [Node] public AnimatedSprite2D AnimatedSprite { get; set; } = default!;

  [Node] public Area3D Hitbox { get; set; } = default!;

  [Node] public AnimationPlayer AnimationPlayer { get; set; } = default!;

  [ExportGroup("Enemy Model Properties")]
  [Export(PropertyHint.Range, "0.0, 1.0")]
  private float _upperThreshold { get; set; } = 0.5f;
  [Export(PropertyHint.Range, "-1.0, 0.0")]
  private float _lowerThreshold { get; set; } = -0.5f;

  EnemyDirection _enemyDirection { get; set; } = EnemyDirection.Forward;

  public new void OnReady()
  {
	Hitbox.AreaEntered += Hitbox_AreaEntered;
	base.OnReady();
  }

  private void Hitbox_AreaEntered(Area3D area) => OnPlayerHit(new AttackEventArgs(new AttackData(10, ElementType.None)));

  public void SetCurrentDirection(Basis enemyBasis, Vector3 cameraDirection) => _enemyDirection = GetEnemyDirection(enemyBasis, cameraDirection, _upperThreshold, _lowerThreshold);

  public override void PlayHitAnimation()
  {
	LoadShader("res://src/vfx/shaders/DamageHit.gdshader");
	var tweener = GetTree().CreateTween();
	tweener.TweenMethod(Callable.From((float x) => SetShaderValue(x)), 0.0f, 1.0f, 1.0f);
  }

  public override void PlayDeathAnimation()
  {
	LoadShader("res://src/vfx/shaders/PixelMelt.gdshader");
	var tweener = GetTree().CreateTween();
	tweener.TweenMethod(Callable.From((float x) => SetShaderValue(x)), 0.0f, 1.0f, 0.8f);
  }

  private EnemyDirection GetEnemyDirection(
	Basis enemyBasis,
	Vector3 cameraDirection,
	float rotateUpperThreshold,
	float rotateLowerThreshold)
  {
	var enemyForwardDirection = enemyBasis.Z;
	var enemyLeftDirection = enemyBasis.X;

	var leftDotProduct = enemyLeftDirection.Dot(cameraDirection);
	var forwardDotProduct = enemyForwardDirection.Dot(cameraDirection);

	// Check if forward facing. If the dot product is -1, the enemy is facing the camera.
	if (forwardDotProduct < _lowerThreshold)
	{
	  SetForward();
	  return EnemyDirection.Forward;
	}

	// Check if backward facing. If the dot product is 1, the enemy is facing the same direction as the camera.
	else if (forwardDotProduct > rotateUpperThreshold)
	{
	  SetBack();
	  return EnemyDirection.Backward;
	}
	else
	{
	  // If the dot product of the perpendicular direction is positive (up to 1), the enemy is facing to the left (since it's mirrored).
	  if (leftDotProduct < _lowerThreshold)
	  {
		SetRight();
		return EnemyDirection.Left;
	  }

	  // Check if side facing. If the dot product is close to zero in the positive or negative direction, its close to the threshold for turning.
	  if (leftDotProduct > rotateUpperThreshold)
	  {
		SetLeft();
		return EnemyDirection.Right;
	  }
	}

	return _enemyDirection;
  }

  private void LoadShader(string shaderPath)
  {
	var shader = GD.Load<Shader>(shaderPath);
	var sprites = FindChildren("*", "AnimatedSprite2D", true).Cast<AnimatedSprite2D>();
	foreach (var sprite in sprites)
	{
	  sprite.Material = new ShaderMaterial();
	  var shaderMaterial = (ShaderMaterial)sprite.Material;
	  shaderMaterial.Shader = shader;
	}
  }

  private void SetShaderValue(float shaderValue)
  {
	var sprites = FindChildren("*", "AnimatedSprite2D", true).Cast<AnimatedSprite2D>();
	foreach (var sprite in sprites)
	{
	  var shaderMaterial = (ShaderMaterial)sprite.Material;
	  shaderMaterial.SetShaderParameter("progress", shaderValue);
	}
  }

  private void SetForward()
  {
	_enemyDirection = EnemyDirection.Forward;
  }

  private void SetLeft()
  {
	_enemyDirection = EnemyDirection.Left;
  }

  private void SetRight()
  {
	_enemyDirection = EnemyDirection.Right;
  }

  private void SetBack()
  {
	_enemyDirection = EnemyDirection.Backward;
  }
}