extends CharacterBody2D

const DAMAGE_POPUP_SCENE := preload("res://scenes/game/damage_popup.tscn")
const IMPACT_EFFECT_SCENE := preload("res://scenes/game/impact_effect.tscn")
const PLASMA_PROJECTILE_SCENE := preload("res://scenes/game/enemy_plasma_projectile.tscn")
const WEAPON_AUDIO_SCRIPT := preload("res://scripts/game/weapon_audio.gd")

@export var max_hull := 50.0
@export var activation_range := 760.0
@export var approach_speed := 62.0
@export var approach_acceleration := 85.0
@export var turn_speed := 1.8
@export var weapon_range := 680.0
@export var weapon_cooldown := 1.5
@export var weapon_damage := 8.0

var hull := 50.0
var _player: CharacterBody2D
var _activated := false
var _sprite: Sprite2D
var _weapon_timer := 0.0

func _ready() -> void:
	hull = max_hull
	_sprite = $Sprite2D
	add_to_group("enemies")
	_weapon_timer = randf_range(0.2, weapon_cooldown)

func configure(player: CharacterBody2D, ship_texture: Texture2D) -> void:
	_player = player
	_sprite = $Sprite2D
	_sprite.texture = ship_texture
	var largest_dimension := maxf(ship_texture.get_width(), ship_texture.get_height())
	_sprite.scale = Vector2.ONE * (56.0 / largest_dimension)

func _physics_process(delta: float) -> void:
	if not is_instance_valid(_player):
		velocity = velocity.move_toward(Vector2.ZERO, approach_acceleration * delta)
		move_and_slide()
		return

	var to_player := _player.global_position - global_position
	if to_player.length() <= activation_range:
		_activated = true
	if _activated and to_player.length_squared() > 1.0:
		var direction := to_player.normalized()
		var desired_rotation := direction.angle() + PI * 0.5
		rotation = rotate_toward(rotation, desired_rotation, turn_speed * delta)
		velocity = velocity.move_toward(direction * approach_speed, approach_acceleration * delta)
		_weapon_timer = maxf(0.0, _weapon_timer - delta)
		if to_player.length() <= weapon_range and _weapon_timer <= 0.0:
			_fire_plasma(direction)
			_weapon_timer = weapon_cooldown
	else:
		velocity = velocity.move_toward(Vector2.ZERO, approach_acceleration * delta)

	move_and_slide()
	_check_player_collision()

func _check_player_collision() -> void:
	for collision_index in get_slide_collision_count():
		var collision := get_slide_collision(collision_index)
		if collision.get_collider() == _player and _player.has_method("register_enemy_collision"):
			_player.call("register_enemy_collision", global_position)

func _fire_plasma(direction: Vector2) -> void:
	var projectile := PLASMA_PROJECTILE_SCENE.instantiate() as Area2D
	projectile.call("configure", global_position + direction * 28.0, direction, weapon_damage)
	get_parent().add_child(projectile)
	WEAPON_AUDIO_SCRIPT.play(get_parent(), global_position, ItemDefinition.WeaponKind.PLASMA, -10.0)

func take_damage(amount: float) -> void:
	hull = maxf(0.0, hull - amount)
	_show_damage_popup(amount)
	if hull <= 0.0:
		_spawn_destruction_effect()
		queue_free()

func _spawn_destruction_effect() -> void:
	var effect := IMPACT_EFFECT_SCENE.instantiate() as Node2D
	effect.global_position = global_position
	get_parent().add_child(effect)
	effect.call("configure", true, Color(1.0, 0.36, 0.18))

func _show_damage_popup(amount: float) -> void:
	var popup := DAMAGE_POPUP_SCENE.instantiate() as Label
	popup.text = "-%s DMG" % _format_damage(amount)
	popup.global_position = global_position + Vector2(randf_range(-16.0, 16.0), -28.0)
	get_parent().add_child(popup)

func _format_damage(amount: float) -> String:
	if is_equal_approx(amount, roundf(amount)):
		return str(int(roundf(amount)))
	return "%.1f" % amount