extends CharacterBody3D
class_name Projectile

const TARGET_ENEMY : int = 1 ## Flag to target enemy
const TARGET_ALLY : int = 2 ## Flag to target ally

const MINIMUN_AREA : float = .1

enum TYPE { ## Types of projectiles
	AOE, ## One target
	BASIC, ## Multiple targets[br]work with [member ProjectileResource.damageArea]
	PIERCING ## Piercing through many enemy[br]work with [member ProjectileResource.maxTarets]
}

var type : TYPE = TYPE.BASIC
var speed : int = 20
var allowedTargets : int = TARGET_ENEMY
var target : PhysicsBody3D
var vectorTarget : Vector3
var maxTargets : int = 1
var damage : int = 1
var enemiesInRange : Array[Enemy]
var affectedTarget : Array[Enemy]
var allyInRange : Array[Tower]

func _physics_process(delta: float) -> void:
	prints(vectorTarget, is_instance_valid(target), vectorTarget == Vector3.ZERO)
	if !is_instance_valid(target) && vectorTarget == Vector3.ZERO:
		queue_free()
		return

	var globalPos : Vector3 = vectorTarget if vectorTarget else target.global_position
	velocity = global_position.direction_to(globalPos) * speed
	look_at(globalPos)
	move_and_slide()


func onBodyEnteredDamageArea(body: Node3D) -> void:
	if type == TYPE.AOE && targetable(body):
		addTarget(body)


func onBodyCollideWithProjectile(body: Node3D) -> void:
	if not affectedTarget.has(body) && (body == target || type == TYPE.PIERCING && targetable(body)):
		addTarget(body)
		resolveDamages()


func targetable(body: Node3D) -> bool:
	if body is Enemy:
		return TARGET_ENEMY & allowedTargets
	if body is Tower:
		return TARGET_ALLY & allowedTargets

	return false


func resolveDamages() -> void:
	for enemy in enemiesInRange:
		if is_instance_valid(enemy):
			maxTargets -= 1
			enemy.take_damage(damage)
			affectedTarget.append(enemy)

	if maxTargets < 1:
		queue_free()


func loadProjectile(resource: ProjectileResource, startPosition: Vector3, _target: PhysicsBody3D) -> void:
	target = _target
	global_position = startPosition
	type = resource.type
	if type == TYPE.PIERCING:
		vectorTarget = target.global_position
		# NOTE removing colision layer for pierce effect
		$HitBox.collision_layer = 0
	speed = resource.speed
	maxTargets = resource.maxTargets
	damage = resource.damage
	allowedTargets = resource.allowedTargets
	$Sprite3D.texture = resource.sprite
	if type == TYPE.AOE && resource.damageArea:
		$DamageArea/ProjectileArea.shape = resource.damageArea


func addTarget(body: Node3D) -> void:
	if body is Enemy:
		enemiesInRange.append(body)
	if body is Tower:
		allyInRange.append(body)


func removeTarget(body: Node3D) -> void:
	if body is Enemy:
		enemiesInRange.erase(body)
	if body is Tower:
		allyInRange.erase(body)