"""在大屏 JSON 副本上移动组件，用于后端校验动作能否执行"""

from app.actions.base import BaseActionHandler
from app.schemas.actions import MoveAction
from app.schemas.screen import Layout, Screen


class MoveHandler(BaseActionHandler[MoveAction]):
    def apply(self, screen: Screen, action: MoveAction) -> Screen:
        result, target = self.copy_target(screen, action.target_id)
        layout = target.layout.model_dump()
        layout["x"] += action.delta_x
        layout["y"] += action.delta_y
        # 重新校验计算结果，防止浮点溢出产生无效坐标
        target.layout = Layout.model_validate(layout)
        return result


if __name__ == "__main__":
    screen = Screen.model_validate(
        {
            "canvas": {"width": 1920, "height": 1080},
            "nodes": [
                {
                    "id": "sales-chart",
                    "type": "chart",
                    "layout": {"x": 100, "y": 200, "width": 400, "height": 300},
                }
            ],
        }
    )
    action = MoveAction(target_id="sales-chart", delta_x=50)
    handler = MoveHandler()
    final_screen = handler.apply(screen, action)
    print(final_screen.model_dump_json(indent=2))
    print("原始坐标:", screen.nodes[0].layout.x, screen.nodes[0].layout.y)

    try:
        handler.apply(screen, MoveAction(target_id="missing", delta_x=50))
    except ValueError as error:
        print("无效目标:", error)