from sqlalchemy.orm import Session
from sqlalchemy import func
from typing import List
import logging

from app.models.location import TAppLocation
from app.schemas.location import LocationQueryRequest
from app.schemas.common import BaseWmsApiResponse, WmsApiResponse
from app.utils.string_utils import pad_left

logger = logging.getLogger(__name__)


class LocationService:

    def __init__(self, db: Session):
        self.db = db

    def gen_locations(self, location_query: LocationQueryRequest) -> BaseWmsApiResponse:
        try:
            new_location_list: List[TAppLocation] = []

            for row in range(1, location_query.l_row + 1):
                for col in range(1, location_query.l_col + 1):
                    for layer in range(1, location_query.l_layer + 1):
                        for depth in range(1, location_query.l_depth + 1):
                            # 生成库位ID，格式：子区域 + 行(2位) + "-" + 列(2位) + "-" + 层(2位) + "-" + 深度(2位)
                            location_id = (
                                f"{location_query.sub_area}"
                                f"{pad_left(str(row), '0', 2)}-"
                                f"{pad_left(str(col), '0', 2)}-"
                                f"{pad_left(str(layer), '0', 2)}-"
                                f"{pad_left(str(depth), '0', 2)}"
                            )

                            new_location = TAppLocation(
                                location_id=location_id,
                                location_name="",
                                location_type=1,
                                is_occupy=0,
                                is_enable=0,
                                equipment_id=0,
                                aisle_num_left=(row + 1) // 2,
                                aisle_num_right=(row + 1) // 2,
                                l_row=row,
                                l_col=col,
                                l_layer=layer,
                                l_depth=depth,
                                remark="",
                                area_id=location_query.area_id if location_query.area_id is not None else 1,
                                sub_area=location_query.sub_area
                            )
                            new_location_list.append(new_location)

            self.db.add_all(new_location_list)
            self.db.commit()

            logger.info(f"成功创建了{len(new_location_list)}个库位")
            return BaseWmsApiResponse.success(f"成功创建了{len(new_location_list)}个库位。")

        except Exception as e:
            self.db.rollback()
            logger.error(f"创建库位失败: {str(e)}")
            return BaseWmsApiResponse.error(f"创建库位失败: {str(e)}")

    def get_used_locations(self, equipment_id: int, location_type: int) -> WmsApiResponse:
        try:
            count = self.db.query(func.count(TAppLocation.location_id)).filter(
                TAppLocation.equipment_id == equipment_id,
                TAppLocation.location_type == location_type,
                TAppLocation.is_occupy == 1
            ).scalar()

            # 确保count不为None
            if count is None:
                count = 0

            return WmsApiResponse.success(data=count, message="查询成功")

        except Exception as e:
            # 打印完整异常信息（包含堆栈）
            logger.exception("查询已使用库位时发生异常")

            # 返回错误响应 - 也使用直接实例化
            return WmsApiResponse.error(
                code=500,
                message=f"查询失败: {type(e).__name__}",
                data=None
            )