# +======================================================================
# | 模块: 城市请求处理器层
# | 说明: 承接城市相关的 HTTP 请求，校验权限/演示模式并记录操作日志后，
# |       转交城市服务层处理（分页、详情、增删改、批量删除等）
# +======================================================================
"""城市请求处理器。"""

# ----------------------------------------------------------------------
# 导入依赖
# 涵盖：权限/演示模式装饰器、操作日志装饰器、统一响应对象、
#       请求处理基类、城市服务单例
# ----------------------------------------------------------------------
from common.middleware.access_decorators import check_demo, permission_required
from common.middleware.operation_log import operation_log
from core import response as R
from core.base_handler import BaseHandler
from core.database import db
from modules.city.models import City
from modules.city.service import city_service


# ======================================================================
# 查询城市数据
# ======================================================================
class CityPageHandler(BaseHandler):
    """查询城市数据。"""

    @permission_required("sys:city:list")
    async def get(self):
        """GET 请求：返回城市分页列表。"""
        return await city_service.get_page(self)


# ======================================================================
# 查询城市详情
# ======================================================================
class CityDetailHandler(BaseHandler):
    """查询城市详情。"""

    @permission_required("sys:city:detail")
    async def get(self, id):
        """GET 请求：按 ID 返回城市详情。

        :param id: 城市 ID（路径参数）
        """
        return R.ok(self, data=city_service.get_detail(id))


# ======================================================================
# 添加城市
# ======================================================================
class CityAddHandler(BaseHandler):
    """添加城市。"""

    @permission_required("sys:city:add")
    @operation_log("城市管理", "添加")
    @check_demo
    async def post(self):
        """POST 请求：新增城市。"""
        return await city_service.add(self)


# ======================================================================
# 更新城市
# ======================================================================
class CityUpdateHandler(BaseHandler):
    """更新城市。"""

    @permission_required("sys:city:update")
    @operation_log("城市管理", "更新")
    @check_demo
    async def put(self):
        """PUT 请求：更新城市信息。"""
        return await city_service.update(self)


# ======================================================================
# 删除城市
# ======================================================================
class CityDeleteHandler(BaseHandler):
    """删除城市。"""

    @permission_required("sys:city:delete")
    @operation_log("城市管理", "删除")
    @check_demo
    async def delete(self, id):
        """DELETE 请求：按 ID 删除城市（软删除）。

        :param id: 城市 ID（路径参数）
        """
        return await city_service.delete(self, id)


# ======================================================================
# 批量删除城市
# ======================================================================
class CityBatchDeleteHandler(BaseHandler):
    """批量删除城市。"""

    @permission_required("sys:city:delete")
    @operation_log("城市管理", "批量删除")
    @check_demo
    async def post(self):
        """POST 请求：批量删除城市（软删除）。"""
        return await city_service.batch_delete(self)


# ======================================================================
# 根据城市编码查询子级城市
# ======================================================================
class CityGetListHandler(BaseHandler):
    """根据城市编码查询子级城市。"""

    async def get(self, city_code):
        """GET 请求：根据城市编码返回子级城市列表。

        :param city_code: 城市编码（路径参数）
        """
        try:
            from sqlalchemy import or_
            city_code = (city_code or '').strip()
            # 顶级(省级)查询：兼容旧数据 '0' 哨兵值与新数据 NULL
            if city_code in ('0', ''):
                items = db.query(City).filter(
                    or_(City.parent_code == '0', City.parent_code.is_(None)),
                    City.is_delete == 0,
                ).all()
            else:
                # 查询子级城市
                items = db.query(City).filter(
                    City.parent_code == city_code, City.is_delete == 0
                ).all()
            # 返回完整结构
            result = [item.to_dict() for item in items]
            return R.ok(self, data=result)
        finally:
            db.close()