from collections.abc import AsyncGenerator
from typing import Any

from fastapi import Depends, FastAPI
from fastapi.concurrency import asynccontextmanager
from fastapi.openapi.docs import get_redoc_html, get_swagger_ui_html, get_swagger_ui_oauth2_redirect_html
from fastapi.responses import HTMLResponse
from fastapi.staticfiles import StaticFiles
from fastapi_cache import FastAPICache
from fastapi_cache.backends.redis import RedisBackend

from .config import path_conf
from .config.setting import settings
from .core.exceptions import handle_exception
from .core.http_limit import WebSocketRateLimiter, limiter
from .core.logger import logger
from .utils.common_util import import_module
from .utils.console import console_end, console_start


@asynccontextmanager
async def lifespan(app: FastAPI) -> AsyncGenerator[Any, Any]:
    from app.api.v1.module_platform.order.service import OrderService
    from app.api.v1.module_platform.tenant.service import TenantService
    from app.api.v1.module_system.dict.service import DictDataService
    from app.api.v1.module_system.log.service import OperationLogService
    from app.api.v1.module_system.params.service import ParamsService
    from app.core.ap_scheduler import SchedulerUtil
    from app.core.database import async_engine, redis_connect
    from app.scripts.initialize import InitializeData

    async def _init_system_caches() -> None:
        """Redis 缓存初始化（参数/数据字典/租户配置）。"""
        await ParamsService.init_cache(redis=app.state.redis)
        logger.info("✅ Redis系统参数初始化完成")
        await DictDataService.init_cache(redis=app.state.redis)
        logger.info("✅ Redis数据字典初始化完成")
        await TenantService.init_cache(redis=app.state.redis)
        logger.info("✅ Redis租户配置初始化完成")

    def _register_system_jobs() -> None:
        """注册系统级定时任务（拆分自 SchedulerUtil._register_system_jobs）。"""
        from apscheduler.triggers.cron import CronTrigger
        from apscheduler.triggers.interval import IntervalTrigger

        SchedulerUtil.register_system_job(
            "system_tenant_expiry_check", TenantService.check_tenant_expiry,
            trigger=IntervalTrigger(hours=1), name="租户到期检查",
        )
        SchedulerUtil.register_system_job(
            "system_clean_expired", TenantService.clean_expired_tenants,
            trigger=CronTrigger(day=1, hour=2, minute=0), name="过期租户归档清理",
        )
        SchedulerUtil.register_system_job(
            "system_cancel_expired_orders", OrderService.cancel_expired_orders,
            trigger=IntervalTrigger(minutes=30), name="超时订单取消",
        )
        SchedulerUtil.register_system_job(
            "system_cleanup_operation_log", OperationLogService.cleanup_operation_log,
            trigger=CronTrigger(day_of_week="sun", hour=3, minute=0), name="操作日志清理",
        )
        logger.info("✅ 4 个系统周期任务已注册（租户到期检查/归档清理/订单取消/日志清理）")

    try:
        await InitializeData().init_db()
        logger.info("✅ {}数据库初始化完成", settings.DATABASE_TYPE)
        await redis_connect(app, status=True)
        logger.info("✅ Redis 连接初始化完成")
        await _init_system_caches()
        await SchedulerUtil.init_scheduler(redis=app.state.redis)
        logger.info("✅ 定时任务调度器初始化完成")
        _register_system_jobs()
        FastAPICache.init(RedisBackend(app.state.redis), prefix="fastapi-admin-cache")
        logger.info("✅ fastapi-admin-cache 初始化完成")
        app.state.limiter = limiter
        logger.info("✅ 请求限流器初始化完成")

        console_start(
            host=settings.SERVER_HOST,
            port=settings.SERVER_PORT,
            reload=settings.DEBUG,
            database_ready=True,
            redis_ready=True,
            scheduler_ready=SchedulerUtil.is_running(),
            limiter_ready=True,
        )
    except Exception as e:
        logger.error("❌ 应用初始化失败: {}", e)
        raise SystemExit(1)

    yield

    try:
        await SchedulerUtil.shutdown(wait=True)
        logger.info("✅ 定时任务调度器已关闭")
        await FastAPICache.clear()
        logger.info("✅ fastapi-admin-cache 已关闭")
        await redis_connect(app, status=False)
        logger.info("✅ Redis 连接已关闭")
        await async_engine.dispose()
        logger.info("✅ 数据库引擎连接池已释放")
        console_end()
    except Exception as e:
        logger.error("❌ 应用关闭过程中发生错误: {}", e)
        raise SystemExit(1)


def register_middlewares(app: FastAPI) -> None:
    for middleware in settings.MIDDLEWARE_LIST[::-1]:
        if not middleware:
            continue
        middleware = import_module(middleware, desc="中间件")
        app.add_middleware(middleware)


def register_exceptions(app: FastAPI) -> None:
    handle_exception(app)


def register_routers(app: FastAPI) -> None:
    from app.api.v1.module_ai import ai_router
    from app.api.v1.module_common import common_router
    from app.api.v1.module_generator import generator_router
    from app.api.v1.module_monitor import monitor_router
    from app.api.v1.module_platform import platform_router
    from app.api.v1.module_system import system_router
    from app.api.v1.module_task import task_router

    app.include_router(common_router)
    app.include_router(monitor_router)
    app.include_router(platform_router)
    app.include_router(system_router)
    app.include_router(ai_router)
    app.include_router(generator_router)
    app.include_router(task_router)

    from app.api.v1.module_ai.chat.ws import WS_AI
    app.include_router(router=WS_AI, dependencies=[Depends(WebSocketRateLimiter(max_calls=200, period=10))])

    from app.core.discover import dynamic_router
    dynamic_router.init_app(app)


def register_static(app: FastAPI) -> None:
    if settings.STATIC_ENABLE:
        settings.STATIC_ROOT.mkdir(parents=True, exist_ok=True)
        app.mount(path=settings.STATIC_URL, app=StaticFiles(directory=settings.STATIC_ROOT), name=settings.STATIC_DIR)


def register_docs(app: FastAPI) -> None:
    """注册文档路由并豁免 slowapi 限流。"""
    swagger_ui_redirect_url = str(app.swagger_ui_oauth2_redirect_url)
    root_openapi_url = str(app.root_path) + str(app.openapi_url)

    # 为文档路由标记 __slower_exempt__ 以跳过 slowapi 中间件限流

    @app.get(swagger_ui_redirect_url, include_in_schema=False)
    async def swagger_ui_redirect():
        return get_swagger_ui_oauth2_redirect_html()

    swagger_ui_redirect.__slower_exempt__ = True

    @app.get(settings.DOCS_URL, include_in_schema=False)
    async def custom_swagger_ui_html() -> HTMLResponse:
        return get_swagger_ui_html(
            openapi_url=root_openapi_url,
            title=app.title + " - Swagger UI",
            oauth2_redirect_url=app.swagger_ui_oauth2_redirect_url,
            swagger_js_url=settings.SWAGGER_JS_URL,
            swagger_css_url=settings.SWAGGER_CSS_URL,
            swagger_favicon_url=settings.FAVICON_URL,
        )

    custom_swagger_ui_html.__slower_exempt__ = True

    @app.get(settings.REDOC_URL, include_in_schema=False)
    async def custom_redoc_html():
        return get_redoc_html(
            openapi_url=root_openapi_url,
            title=app.title + " - ReDoc",
            redoc_js_url=settings.REDOC_JS_URL,
            redoc_favicon_url=settings.FAVICON_URL,
        )

    custom_redoc_html.__slower_exempt__ = True


def register_frontend(app: FastAPI) -> None:
    if path_conf.FRONTEND_DIST_DIR.exists():
        app.mount("/web", StaticFiles(directory=str(path_conf.FRONTEND_DIST_DIR), html=True), name="frontend")