import router from '@/routers'
import { LOGIN_URL } from '@/config'
import { type RouteRecordRaw } from 'vue-router'
import { ElNotification } from 'element-plus'
import { useUserStore } from '@/stores/modules/user'
import { useAuthStore } from '@/stores/modules/auth'

const modules = import.meta.glob('@/views/**/*.vue')
const VIEWS_ALIAS_PREFIX = '@/views'
const VIEWS_SRC_PREFIX = '/src/views'
const ROUTER_PERF_DEBUG = import.meta.env.DEV
const perfNow = () => (typeof performance !== 'undefined' ? performance.now() : Date.now())
const logRouterPerf = (label: string, start: number, extra?: Record<string, unknown>) => {
    if (!ROUTER_PERF_DEBUG) return
    const duration = Math.round((perfNow() - start) * 100) / 100
    console.info(`[router-perf] ${label}`, { duration, ...extra })
}
const COMPONENT_PATH_ALIASES: Record<string, string> = {
    // 后端菜单沿用 event-list 模块名时，前端实际页面目录为 eventList。
    '/event/event-list': '/event/eventList',
    '/event/event-list/index': '/event/eventList/index',
    // 后端菜单可能使用短横线模块名，前端页面目录统一为 steadyDataView。
    '/steady/steady-data-view': '/steady/steadyDataView',
    '/steady/steady-data-view/index': '/steady/steadyDataView/index',
    '/steady/steady-trend': '/steady/steadyTrend',
    '/steady/steady-trend/index': '/steady/steadyTrend/index',
    '/steady/check-square': '/steady/checksquare',
    '/steady/check-square/index': '/steady/checksquare/index',
    // 数据库监控菜单统一落到 system-ops/dbms 页面，兼容后端菜单常见 component 写法。
    '/system-monitor/dbms': '/system-ops/dbms',
    '/system-monitor/dbms/index': '/system-ops/dbms/index',
    '/system-monitor/databaseMonitor': '/system-ops/dbms',
    '/system-monitor/databaseMonitor/index': '/system-ops/dbms/index',
    '/system-monitor/database-monitor': '/system-ops/dbms',
    '/system-monitor/database-monitor/index': '/system-ops/dbms/index',
    '/systemMonitor/dbms': '/system-ops/dbms',
    '/systemMonitor/dbms/index': '/system-ops/dbms/index',
    '/systemMonitor/databaseMonitor': '/system-ops/dbms',
    '/systemMonitor/databaseMonitor/index': '/system-ops/dbms/index',
    '/systemMonitor/database-monitor': '/system-ops/dbms',
    '/systemMonitor/database-monitor/index': '/system-ops/dbms/index',
    '/system-ops/database-monitor': '/system-ops/dbms',
    '/system-ops/database-monitor/index': '/system-ops/dbms/index',
    // 报告菜单后端使用 aiReport，前端目录沿用既有 aireport 命名。
    '/aiReport/reportTask': '/aireport/testReport',
    '/aiReport/reportTask/index': '/aireport/testReport/index',
    '/aiReport/testReport': '/aireport/testReport',
    '/aiReport/testReport/index': '/aireport/testReport/index',
    '/aiReport/reportModel': '/aireport/reportModel',
    '/aiReport/reportModel/index': '/aireport/reportModel/index',
    '/aiReport/clientUnit': '/aireport/clientUnit',
    '/aiReport/clientUnit/index': '/aireport/clientUnit/index',
    '/aiReport/testDevice': '/aireport/testDevice',
    '/aiReport/testDevice/index': '/aireport/testDevice/index',
    '/aiReport/reportApproval': '/aireport/reportApproval',
    '/aiReport/reportApproval/index': '/aireport/reportApproval/index'
}
const STATIC_ROUTE_NAMES = new Set([
    'layout',
    'login',
    'home',
    'tools',
    'toolWaveform',
    'toolMmsMapping',
    'toolParsePqdif',
    'deviceTypes',
    'toolAddData',
    'toolAddLedger',
    'eventList',
    'steadyDataView',
    'steadyTrend',
    'checksquare',
    'system-monitor',
    'systemMonitor',
    'diskMonitor',
    'systemOpsDbms',
    '403',
    '404',
    '500'
])

let isInitializing = false

/**
 * 清除已有的动态路由，避免重复注入。
 */
const clearDynamicRoutes = () => {
    const routes = router.getRoutes()
    routes.forEach(route => {
        if (route.name && !STATIC_ROUTE_NAMES.has(String(route.name))) {
            router.removeRoute(route.name)
        }
    })
}

/**
 * 统一菜单 component 配置格式，只允许映射到 views 目录。
 */
const normalizeComponentPath = (path: string) => {
    let normalizedPath = path.trim().replace(/\\/g, '/')

    if (normalizedPath.startsWith(VIEWS_ALIAS_PREFIX)) {
        normalizedPath = normalizedPath.slice(VIEWS_ALIAS_PREFIX.length)
    } else if (normalizedPath.startsWith(VIEWS_SRC_PREFIX)) {
        normalizedPath = normalizedPath.slice(VIEWS_SRC_PREFIX.length)
    } else if (normalizedPath.startsWith('src/views')) {
        normalizedPath = normalizedPath.slice('src/views'.length)
    }

    if (!normalizedPath.startsWith('/')) {
        normalizedPath = '/' + normalizedPath
    }
    if (normalizedPath.endsWith('.vue')) {
        normalizedPath = normalizedPath.slice(0, -4)
    }
    if (normalizedPath.length > 1 && normalizedPath.endsWith('/')) {
        normalizedPath = normalizedPath.slice(0, -1)
    }

    return COMPONENT_PATH_ALIASES[normalizedPath] ?? normalizedPath
}

/**
 * 根据菜单 component 路径查找对应页面模块。
 * 兼容菜单资源里常见的多种写法，避免因为前缀或 index 差异导致误判。
 */
const resolveComponentModule = (path: string) => {
    const normalizedPath = normalizeComponentPath(path)
    const viewPath = normalizedPath.endsWith('/index') ? normalizedPath.slice(0, -'/index'.length) : normalizedPath
    const candidatePaths = Array.from(
        new Set([
            `${VIEWS_ALIAS_PREFIX}${normalizedPath}.vue`,
            `${VIEWS_ALIAS_PREFIX}${normalizedPath}/index.vue`,
            `${VIEWS_ALIAS_PREFIX}${viewPath}/index.vue`,
            `${VIEWS_SRC_PREFIX}${normalizedPath}.vue`,
            `${VIEWS_SRC_PREFIX}${normalizedPath}/index.vue`,
            `${VIEWS_SRC_PREFIX}${viewPath}/index.vue`
        ])
    )

    for (const candidatePath of candidatePaths) {
        if (candidatePath in modules) {
            return {
                moduleLoader: modules[candidatePath],
                resolvedPath: candidatePath
            }
        }
    }

    return {
        moduleLoader: undefined,
        resolvedPath: candidatePaths
    }
}

/**
 * 初始化动态路由。
 */
export const initDynamicRouter = async () => {
    if (isInitializing) return Promise.reject(new Error('Dynamic router initialization in progress'))

    isInitializing = true
    const initStart = perfNow()
    const userStore = useUserStore()
    const authStore = useAuthStore()
    const unresolvedRoutes: Array<{ name?: string; path?: string; component?: string; candidates: string[] }> = []

    try {
        const menuStart = perfNow()
        await authStore.getAuthMenuList()
        logRouterPerf('dynamic-router-load-menus-api', menuStart)

        const flattenMenuStart = perfNow()
        const flatMenuList = authStore.flatMenuListGet
        logRouterPerf('dynamic-router-flatten-menus', flattenMenuStart, {
            menuCount: flatMenuList.length
        })

        const buttonStart = perfNow()
        await authStore.getAuthButtonList()
        logRouterPerf('dynamic-router-load-buttons', buttonStart)

        if (!authStore.authMenuListGet.length) {
            ElNotification({
                title: '无权限访问',
                message: '当前账号无任何菜单权限，请联系系统管理员',
                type: 'warning',
                duration: 3000
            })
            userStore.setAccessToken('')
            userStore.setRefreshToken('')
            userStore.setExp(0)
            await router.replace(LOGIN_URL)
            return Promise.reject('No permission')
        }

        const clearStart = perfNow()
        clearDynamicRoutes()
        logRouterPerf('dynamic-router-clear-routes', clearStart)

        const addRoutesStart = perfNow()
        let addedRouteCount = 0
        for (const item of flatMenuList) {
            if (item.children) delete item.children
            if (item.name && STATIC_ROUTE_NAMES.has(String(item.name))) {
                continue
            }

            // 动态菜单组件必须先映射成真实页面模块，否则 addRoute 后会直接落到 404。
            if (item.component && typeof item.component === 'string') {
                const { moduleLoader, resolvedPath } = resolveComponentModule(item.component)
                if (moduleLoader) {
                    item.component = moduleLoader
                } else {
                    unresolvedRoutes.push({
                        name: item.name,
                        path: item.path,
                        component: item.component,
                        candidates: resolvedPath
                    })
                    continue
                }
            }

            if (
                typeof item.path === 'string' &&
                (typeof item.component === 'function' || typeof item.redirect === 'string')
            ) {
                const routeItem = item as unknown as RouteRecordRaw
                if (item.meta?.isFull) {
                    router.addRoute(routeItem)
                } else {
                    router.addRoute('layout', routeItem)
                }
                addedRouteCount += 1
            } else {
                console.warn('Invalid route item:', item)
            }
        }
        logRouterPerf('dynamic-router-add-routes', addRoutesStart, {
            menuCount: flatMenuList.length,
            addedRouteCount,
            unresolvedRouteCount: unresolvedRoutes.length
        })

        if (unresolvedRoutes.length) {
            console.error('[dynamic-router] unresolved route components', unresolvedRoutes)
        }
    } catch (error) {
        userStore.setAccessToken('')
        userStore.setRefreshToken('')
        userStore.setExp(0)
        await router.replace(LOGIN_URL)
        return Promise.reject(error)
    } finally {
        logRouterPerf('dynamic-router-total', initStart, {
            unresolvedRouteCount: unresolvedRoutes.length
        })
        isInitializing = false
    }
}