extends AnimatedSprite2D

const FOG_COLOR_DEFAULT = Color(0.8, 0.8, 0.8, 0.8)
const FOG_COLOR_WHITE = Color(1, 1, 1, 1)
const FOG_COLOR_BLACK = Color(0, 0, 0, 1)
const FOG_COLOR_GRAY = Color(0.5, 0.5, 0.5, 1)
const FOG_COLOR_DARK_GRAY = Color(0.2, 0.2, 0.2, 1)

var FOG_FRAME_MIN = 0
var FOG_FRAME_MAX
var FOG_FRAME_DEFAULT

const FOG_OFFSET_DEFAULT = Vector2(0, 50)


func _ready() -> void:
	FOG_FRAME_MAX = sprite_frames.get_frame_count(animation) - 1
	FOG_FRAME_DEFAULT = FOG_FRAME_MAX


var _fog_tween: Tween


func tween_fog(
	end_frame := frame,
	end_modulate := modulate,
	end_offset := offset,
	duration := 0.8,
	close_at_end := false
) -> void:
	if not is_node_ready():
		return
	if GlobalConfig.DEBUG:
		print(
			"Tween fog to frame: ", end_frame, " modulate: ", end_modulate, " offset: ", end_offset
		)
	if not visible:
		# 如果没有开启 fog，先开启，并且设置为透明
		visible = true
		modulate = Color.TRANSPARENT
	if _fog_tween and _fog_tween.is_valid():
		_fog_tween.kill()
	_fog_tween = create_tween()
	_fog_tween.tween_property(self, "frame", end_frame, duration)
	if end_modulate != modulate:
		_fog_tween.parallel().tween_property(self, "self_modulate", end_modulate, duration)
	if end_offset != offset:
		_fog_tween.parallel().tween_property(self, "offset", end_offset, duration)
	if close_at_end:
		_fog_tween.tween_callback(hide)