/**
 * MonitorTab 组件
 * 
 * 系统监控仪表板Tab组件
 * 从主页面拆分出来，负责显示系统监控数据
 * 包括用户统计、素材统计、系统状态等信息
 * 使用三层架构样式系统，支持深浅色主题
 * 
 * @created 2025-01-XX（拆分自 page.tsx）
 * @component
 */

'use client'

import { useEffect, useMemo } from 'react'
import { useSession } from 'next-auth/react'
import { useThemeStyles, useTheme, cn } from '@/lib/ui-styles'
import { formatDateTimeLocale } from '../_utils/formatters'
import type { ToastFn, DashboardData } from './types'
import { useDashboardData } from '../_hooks/useDashboardData'
import LoadingState from './ui/LoadingState'
import ErrorState from './ui/ErrorState'
import EmptyState from './ui/EmptyState'

interface MonitorTabProps {
  showToast: ToastFn
}

const AUTO_REFRESH_INTERVAL = 60_000

export default function MonitorTab({ showToast }: MonitorTabProps) {
  const styles = useThemeStyles()
  const theme = useTheme()
  
  // 根据主题选择颜色类名
  const borderColor = theme === 'dark' ? 'border-slate-800/70' : 'border-slate-200/70'
  const textTitle = theme === 'dark' ? 'text-white' : 'text-slate-900'
  const textDesc = theme === 'dark' ? 'text-slate-400' : 'text-slate-500'
  const textLabel = theme === 'dark' ? 'text-slate-400' : 'text-slate-500'
  const textValue = theme === 'dark' ? 'text-white' : 'text-slate-900'
  const borderRow = theme === 'dark' ? 'border-slate-700' : 'border-slate-200'
  const textRow = theme === 'dark' ? 'text-slate-400' : 'text-slate-600'
  const { data: session } = useSession()
  const currentIsSuperAdmin = Boolean((session?.user as any)?.isSuperAdmin)
  const { data, loading, error, refresh, updateSystemSetting, lastUpdated, refreshing } = useDashboardData({ showToast })

  useEffect(() => {
    refresh()
  }, [refresh])

  useEffect(() => {
    const timer = setInterval(() => {
      void refresh({ background: true })
    }, AUTO_REFRESH_INTERVAL)
    return () => clearInterval(timer)
  }, [refresh])

  const materialUploadMax = useMemo(() => {
    if (!data?.trends.materialUploads?.length) return 1
    return Math.max(...data.trends.materialUploads.map((item) => item.count), 1)
  }, [data?.trends.materialUploads])

  const formattedLastUpdated = useMemo(() => {
    if (!lastUpdated) return '尚未获取'
    return formatDateTimeLocale(lastUpdated, 'zh-CN', { hour12: false })
  }, [lastUpdated])

  const handleManualRefresh = () => {
    void refresh({ background: Boolean(data) })
  }

  if (loading) {
    return <LoadingState message="加载系统监控数据..." />
  }

  if (error) {
    return <ErrorState message={error} onRetry={() => refresh()} />
  }

  if (!data) {
    return <EmptyState message="暂无数据" />
  }

  const handleToggle = (key: SystemSettingKey, value: boolean) => {
    void updateSystemSetting(key, value).catch(() => undefined)
  }

  return (
    <div className="space-y-8">
      <section
        className={cn(
          'relative overflow-hidden rounded-3xl border mb-6 flex-shrink-0',
          theme === 'dark'
            ? 'border-slate-600/60 text-white shadow-[0_28px_60px_rgba(139,92,246,0.2)] hover:shadow-[0_35px_65px_rgba(139,92,246,0.3)]'
            : 'border-slate-200/70 text-slate-900 shadow-[0_28px_60px_rgba(15,23,42,0.28)] hover:shadow-[0_35px_65px_rgba(15,23,42,0.35)]',
          'transition-all duration-500 p-6',
        )}
      >
        <div className="relative z-10 flex flex-col gap-4 lg:flex-row lg:items-center lg:justify-between">
          <div className="space-y-3">
            <p className={cn('text-sm font-semibold tracking-[0.2em] uppercase', theme === 'dark' ? 'text-indigo-400' : 'text-indigo-600')}>
              System Monitor
            </p>
            <h2 className={cn('text-2xl font-semibold', textTitle)}>系统监控概览</h2>
            <p className={cn('text-sm leading-relaxed', textDesc)}>最近更新：{formattedLastUpdated}</p>
          </div>
          <div className="flex items-center gap-3">
            {refreshing && (
              <span className={cn('text-xs flex items-center gap-1', textDesc)}>
                <span className="inline-block h-3 w-3 rounded-full border-2 border-slate-300 border-t-indigo-500 animate-spin" />
                后台同步中...
              </span>
            )}
            <button
              type="button"
              className={cn(
                styles.buttonStyles.secondary,
                'flex items-center gap-2',
                'bg-white dark:bg-slate-800 border-slate-300 dark:border-slate-600 text-slate-700 dark:text-slate-200' // 显式添加背景色、边框和文字色
              )}
              onClick={handleManualRefresh}
            >
              <svg className={cn('w-4 h-4', refreshing && 'animate-spin')} fill="none" stroke="currentColor" viewBox="0 0 24 24">
                <path strokeLinecap="round" strokeLinejoin="round" strokeWidth={2} d="M4 4v6h6M20 20v-6h-6M5 19a9 9 0 0014-7 9 9 0 00-9-9" />
              </svg>
              刷新数据
            </button>
          </div>
        </div>
      </section>

      <div className="grid grid-cols-1 md:grid-cols-2 lg:grid-cols-5 gap-6">
        {OVERVIEW_CARDS.map((card) => (
          <div key={card.label} className={cn(styles.cardStyles.base, 'overflow-hidden')}>
            <div className="p-5">
              <div className="flex items-center">
                <div className="flex-shrink-0">
                  <div className={cn('w-8 h-8 rounded-full flex items-center justify-center shadow-sm', card.className)}>
                    <span className="text-white font-medium">{card.icon}</span>
                  </div>
                </div>
                <div className="ml-5 w-0 flex-1">
                  <dl>
                    <dt className={cn('text-sm font-medium truncate', textLabel)}>{card.label}</dt>
                    <dd className={cn('text-lg font-semibold', textValue)}>{card.getValue(data)}</dd>
                  </dl>
                </div>
              </div>
            </div>
          </div>
        ))}
      </div>

      <div className={cn(styles.cardStyles.base)}>
        <h3 className={cn('text-lg font-semibold mb-4', textTitle)}>📊 素材上传趋势（最近12个月）</h3>
        <div className="h-64 overflow-y-auto">
          {data.trends.materialUploads.length ? (
            <div className="space-y-2">
              {data.trends.materialUploads.map((item) => (
                <div
                  key={item.date}
                  className={cn('flex justify-between items-center py-2 border-b', borderRow)}
                >
                  <span className={cn('text-sm', textRow)}>{item.date}</span>
                  <div className="flex items-center">
                    <div className="w-32 bg-slate-200 dark:bg-slate-700 rounded-full h-2 mr-3">
                      <div
                        className="bg-purple-600 dark:bg-purple-500 h-2 rounded-full transition-all"
                        style={{ width: `${Math.min(100, (item.count / materialUploadMax) * 100)}%` }}
                      />
                    </div>
                    <span className={cn('text-sm font-semibold', textValue)}>{item.count}</span>
                  </div>
                </div>
              ))}
            </div>
          ) : (
            <div className={cn('h-full flex items-center justify-center text-sm', textDesc)}>
              暂无趋势数据
            </div>
          )}
        </div>
      </div>

      <div className="grid grid-cols-1 lg:grid-cols-3 gap-8">
        <div className={cn(styles.cardStyles.base)}>
          <h3 className="text-lg font-semibold text-slate-900 dark:text-white mb-4">🏢 部门分布</h3>
          <div className="space-y-3">
            {data.distribution.departments.length ? (
              data.distribution.departments.map((item) => (
                <div key={`${item.department || 'unknown'}`} className="flex justify-between items-center">
                  <span className={cn('text-sm', textRow)}>{item.department || '未设置'}</span>
                  <span className={cn('text-sm font-semibold', textValue)}>{item.count}</span>
                </div>
              ))
            ) : (
              <p className={cn('text-sm', textDesc)}>暂无部门分布数据</p>
            )}
          </div>
        </div>

        <div className={cn(styles.cardStyles.base)}>
          <h3 className={cn('text-lg font-semibold mb-4', textTitle)}>🛡️ 权限分布</h3>
          <div className="space-y-3">
            {data.distribution.roles.length ? (
              data.distribution.roles.map((item, index) => (
                <div key={`${item.role}-${index}`} className="flex justify-between items-center">
                  <span className={cn('text-sm', textRow)}>
                    {item.role === 'ADMIN' && item.isSuperAdmin
                      ? '超级管理员'
                      : item.role === 'ADMIN'
                        ? '管理员'
                        : '普通用户'}
                  </span>
                  <span className={cn('text-sm font-semibold', textValue)}>{item.count}</span>
                </div>
              ))
            ) : (
              <p className={cn('text-sm', textDesc)}>暂无权限分布数据</p>
            )}
          </div>
        </div>

        <div className={cn(styles.cardStyles.base)}>
          <h3 className={cn('text-lg font-semibold mb-4', textTitle)}>⚙️ 系统信息</h3>
          <div className="space-y-3">
            <SystemToggleRow
              label="注册功能"
              editable={currentIsSuperAdmin}
              enabled={data.systemInfo.registrationEnabled}
              onToggle={(value) => handleToggle('registrationEnabled', value)}
              activeText="开启"
              inactiveText="关闭"
            />
            <SystemToggleRow
              label="用户激活"
              editable={currentIsSuperAdmin}
              enabled={data.systemInfo.userActivationRequired}
              onToggle={(value) => handleToggle('userActivationRequired', value)}
              activeText="需要"
              inactiveText="关闭"
            />
            <div className="flex justify-between items-center">
              <span className="text-sm text-slate-600 dark:text-slate-400">数据库状态</span>
              <span
                className={cn(
                  'text-sm font-medium',
                  data.status.database === 'healthy' ? 'text-green-600 dark:text-green-400' : 'text-red-600 dark:text-red-400',
                )}
              >
                {data.status.database === 'healthy' ? '正常' : '异常'}
              </span>
            </div>
            <div className="flex justify-between items-center">
              <span className="text-sm text-slate-600 dark:text-slate-400">运行时间</span>
              <span className="text-sm font-semibold text-slate-900 dark:text-white">
                {Math.floor(data.status.uptime / 3600)} 小时
              </span>
            </div>
          </div>
        </div>
      </div>

      <div className={cn(styles.cardStyles.base)}>
        <h3 className={cn('text-lg font-semibold mb-4', textTitle)}>🕒 最近活动</h3>
        <div className="overflow-x-auto">
          <table className={cn('min-w-full divide-y', theme === 'dark' ? 'divide-slate-700' : 'divide-slate-200')}>
            <thead className={theme === 'dark' ? 'bg-slate-700' : 'bg-slate-50'}>
              <tr>
                <th className={cn('px-6 py-3 text-left text-xs font-medium uppercase tracking-wider', theme === 'dark' ? 'text-slate-300' : 'text-slate-500')}>
                  素材标题
                </th>
                <th className="px-6 py-3 text-left text-xs font-medium text-slate-500 dark:text-slate-300 uppercase tracking-wider">
                  上传者
                </th>
                <th className="px-6 py-3 text-left text-xs font-medium text-slate-500 dark:text-slate-300 uppercase tracking-wider">
                  上传时间
                </th>
              </tr>
            </thead>
            <tbody className={cn('divide-y', theme === 'dark' ? 'bg-slate-800 divide-slate-700' : 'bg-white divide-slate-200')}>
              {data.recentActivity.map((activity) => (
                <tr key={activity.id} className={theme === 'dark' ? 'hover:bg-slate-700' : 'hover:bg-slate-50'}>
                  <td className={cn('px-6 py-4 whitespace-nowrap text-sm', textValue)}>{activity.title}</td>
                  <td className={cn('px-6 py-4 whitespace-nowrap text-sm', textDesc)}>
                    {activity.uploadedBy.username}
                  </td>
                  <td className={cn('px-6 py-4 whitespace-nowrap text-sm', textDesc)}>
                    {new Date(activity.createdAt).toLocaleString('zh-CN')}
                  </td>
                </tr>
              ))}
            </tbody>
          </table>
        </div>
      </div>
    </div>
  )
}

type SystemSettingKey = 'registrationEnabled' | 'userActivationRequired'

const OVERVIEW_CARDS: Array<{
  label: string
  icon: string
  className: string
  getValue: (data: DashboardData) => number
}> = [
  {
    label: '总用户数',
    icon: '👥',
    className: 'bg-blue-500 shadow-blue-500/40',
    getValue: (data) => data.overview.totalUsers,
  },
  {
    label: '活跃用户',
    icon: '⚡',
    className: 'bg-green-500 shadow-green-500/40',
    getValue: (data) => data.overview.activeUsers,
  },
  {
    label: '总素材数',
    icon: '📦',
    className: 'bg-purple-500 shadow-purple-500/40',
    getValue: (data) => data.overview.totalMaterials,
  },
  {
    label: '本月新用户',
    icon: '🆕',
    className: 'bg-yellow-500 shadow-yellow-500/40',
    getValue: (data) => data.overview.newUsersThisMonth,
  },
  {
    label: '本月新素材',
    icon: '📈',
    className: 'bg-indigo-500 shadow-indigo-500/40',
    getValue: (data) => data.overview.newMaterialsThisMonth,
  },
]

interface SystemToggleRowProps {
  label: string
  enabled: boolean
  editable: boolean
  onToggle: (value: boolean) => void
  activeText: string
  inactiveText: string
}

function SystemToggleRow({ label, enabled, editable, onToggle, activeText, inactiveText }: SystemToggleRowProps) {
  // 需要使用主题 Hook，但这个组件在函数外部定义，暂时保留 dark: 前缀
  // 可以考虑将这个组件移到函数内部或传入 theme 参数
  if (!editable) {
    return (
      <div className="flex justify-between items-center">
        <span className="text-sm text-slate-600 dark:text-slate-400">{label}</span>
        <span className={cn('text-sm font-medium', enabled ? 'text-green-600 dark:text-green-400' : 'text-slate-500 dark:text-slate-400')}>
          {enabled ? activeText : inactiveText}
        </span>
      </div>
    )
  }

  return (
    <div className="flex justify-between items-center">
      <span className="text-sm text-slate-600 dark:text-slate-400">{label}</span>
      <label className="relative inline-flex items-center cursor-pointer">
        <input
          type="checkbox"
          className="sr-only peer"
          checked={enabled}
          onChange={(event) => onToggle(event.target.checked)}
        />
        <div className="w-11 h-6 bg-slate-200 peer-focus:outline-none peer-focus:ring-4 peer-focus:ring-blue-300 dark:peer-focus:ring-blue-800 rounded-full peer dark:bg-slate-700 peer-checked:after:translate-x-full peer-checked:after:border-white after:content-[''] after:absolute after:top-[2px] after:left-[2px] after:bg-white after:border-slate-300 after:border after:rounded-full after:h-5 after:w-5 after:transition-all dark:border-slate-600 peer-checked:bg-blue-600" />
      </label>
    </div>
  )
}