# ============================================================================
# 简单草地瓦片 - GrassTile.gd
# 
# 一个简单的32x32草地瓦片，自动对齐网格
# 使用方法：
#   1. 在场景中实例化 grass_tile_prefab.tscn
#   2. 设置 texture 属性
#   3. 调用 set_grid_position() 设置网格位置
# ============================================================================

class_name GrassTile
extends Sprite2D

# ============================================================================
# 导出属性
# ============================================================================
@export var grid_position: Vector2i = Vector2i.ZERO : set = set_grid_position
@export var auto_snap: bool = true  # 是否自动对齐网格

# ============================================================================
# 信号
# ============================================================================
signal position_changed(new_grid_pos: Vector2i)

func _ready():
	# 如果没有纹理，创建一个默认的占位符
	if not texture:
		_create_placeholder_texture()
	
	# 验证纹理尺寸
	_validate_texture()
	
	# 自动对齐到网格
	if auto_snap:
		snap_to_grid()

# ============================================================================
# 公共方法
# ============================================================================

# 设置网格位置并自动对齐
func set_grid_position(new_pos: Vector2i):
	if grid_position != new_pos:
		grid_position = new_pos
		if auto_snap:
			snap_to_grid()
		position_changed.emit(grid_position)

# 对齐到网格中心
func snap_to_grid():
	position = Vector2(
		grid_position.x * 32.0 + 16.0,
		grid_position.y * 32.0 + 16.0
	)

# 从世界坐标设置位置（会自动转换为网格坐标）
func set_world_position(world_pos: Vector2):
	var new_grid_pos = Vector2i(
		int(world_pos.x / 32.0),
		int(world_pos.y / 32.0)
	)
	set_grid_position(new_grid_pos)

# 获取世界坐标
func get_world_position() -> Vector2:
	return position

# ============================================================================
# 私有方法
# ============================================================================

# 创建占位符纹理
func _create_placeholder_texture():
	var image = Image.create(32, 32, false, Image.FORMAT_RGBA8)
	
	# 创建简单的草地图案
	var grass_color = Color(0.3, 0.8, 0.3, 1.0)  # 亮绿色
	var dark_color = Color(0.2, 0.6, 0.2, 1.0)   # 深绿色
	
	# 填充基础颜色
	image.fill(grass_color)
	
	# 添加简单的格子图案
	for x in range(32):
		for y in range(32):
			if (x + y) % 8 < 4:
				image.set_pixel(x, y, dark_color)
	
	# 创建纹理
	var placeholder_texture = ImageTexture.new()
	placeholder_texture.set_image(image)
	texture = placeholder_texture

# 验证纹理尺寸
func _validate_texture():
	if texture:
		var size = Vector2i(texture.get_width(), texture.get_height())
		if size.x % 32 != 0 or size.y % 32 != 0:
			push_warning("GrassTile: 纹理尺寸不是32的倍数: " + str(size))
			return false
		return true
	return false

# ============================================================================
# 调试方法
# ============================================================================

# 获取瓦片信息
func get_tile_info() -> Dictionary:
	return {
		"grid_position": grid_position,
		"world_position": position,
		"texture_size": texture.get_size() if texture else Vector2.ZERO,
		"auto_snap": auto_snap
	}

# 打印瓦片信息
func print_info():
	var info = get_tile_info()
	print("=== 草地瓦片信息 ===")
	for key in info:
		print(key, ": ", info[key])