import React, { useState, useEffect } from 'react';
import { LogOut, User, Users, Activity, Server, HardDrive, Cpu, MemoryStick, RefreshCw, UserX, ChevronDown, KeyRound, Shield, BookText, Waves, UserCog, Search } from 'lucide-react';
import apiClient from '../utils/apiClient';
import { buildApiUrl, API_ENDPOINTS } from '../config/api';
import Dropdown from '../components/Dropdown';
import menuService from '../services/menuService';
import ConfirmDialog from '../components/ConfirmDialog';
import Toast from '../components/Toast';
import PageLoading from '../components/PageLoading';
import FormModal from '../components/FormModal';
import './AdminDashboard.css';

// 常量定义
const AUTO_REFRESH_INTERVAL = 30; // 自动刷新间隔（秒）
const STATUS_BADGE_MAP = {
  'pending': 'status-badge status-pending',
  'processing': 'status-badge status-processing',
  'completed': 'status-badge status-completed',
  'failed': 'status-badge status-failed'
};
const STATUS_TEXT_MAP = {
  'pending': '待处理',
  'processing': '处理中',
  'completed': '已完成',
  'failed': '失败'
};
const TASK_TYPE_TEXT_MAP = {
  'transcription': '转录',
  'summary': '总结',
  'knowledge_base': '知识库'
};

// 辅助函数
const getStatusBadgeClass = (status) => STATUS_BADGE_MAP[status] || 'status-badge';
const getStatusText = (status) => STATUS_TEXT_MAP[status] || status;
const getTaskTypeText = (type) => TASK_TYPE_TEXT_MAP[type] || type;

// 默认管理员菜单
const getDefaultMenus = () => [
  { menu_code: 'account_settings', menu_name: '账户设置', menu_type: 'link', menu_url: '/account-settings' },
  { menu_code: 'prompt_management', menu_name: '提示词仓库', menu_type: 'link', menu_url: '/prompts' },
  { menu_code: 'platform_admin', menu_name: '平台管理', menu_type: 'link', menu_url: '/admin' },
  { menu_code: 'logout', menu_name: '退出登录', menu_type: 'action' }
];

const AdminDashboard = ({ user, onLogout }) => {
  // 统计数据
  const [stats, setStats] = useState(null);
  const [onlineUsers, setOnlineUsers] = useState([]);
  const [usersList, setUsersList] = useState([]);
  const [tasks, setTasks] = useState([]);
  const [resources, setResources] = useState(null);
  const [loading, setLoading] = useState(true);
  const [error, setError] = useState('');

  // 菜单权限相关状态
  const [userMenus, setUserMenus] = useState([]);

  // 任务筛选
  const [taskType, setTaskType] = useState('all');
  const [taskStatus, setTaskStatus] = useState('all');

  // 自动刷新定时器
  const [autoRefresh, setAutoRefresh] = useState(true);
  const [countdown, setCountdown] = useState(AUTO_REFRESH_INTERVAL);

  // Toast和确认对话框
  const [toasts, setToasts] = useState([]);
  const [kickConfirmInfo, setKickConfirmInfo] = useState(null);
  
  // 会议详情模态框
  const [showMeetingModal, setShowMeetingModal] = useState(false);
  const [meetingDetails, setMeetingDetails] = useState(null);
  const [meetingLoading, setMeetingLoading] = useState(false);

  // Toast辅助函数
  const showToast = (message, type = 'info') => {
    const id = Date.now();
    setToasts(prev => [...prev, { id, message, type }]);
  };

  const removeToast = (id) => {
    setToasts(prev => prev.filter(toast => toast.id !== id));
  };

  // 获取菜单配置
  const getMenuItemConfig = (menu) => {
    const iconMap = {
      'change_password': <KeyRound size={16} />,
      'account_settings': <UserCog size={16} />,
      'prompt_management': <BookText size={16} />,
      'platform_admin': <Shield size={16} />,
      'logout': <LogOut size={16} />
    };

    const actionMap = {
      'logout': onLogout
    };

    return {
      icon: iconMap[menu.menu_code],
      label: menu.menu_name,
      onClick: menu.menu_type === 'link' && menu.menu_url
        ? () => window.location.href = menu.menu_url
        : actionMap[menu.menu_code]
    };
  };

  // 获取用户菜单权限
  const fetchUserMenus = async () => {
    try {
      const response = await menuService.getUserMenus();
      if (response.code === '200') {
        setUserMenus(response.data.menus || []);
      } else {
        setUserMenus(getDefaultMenus());
      }
    } catch (error) {
      console.error('Error fetching user menus:', error);
      setUserMenus(getDefaultMenus());
    }
  };

  // 初始化和自动刷新
  useEffect(() => {
    fetchAllData();
    fetchUserMenus();
  }, []);

  useEffect(() => {
    if (autoRefresh && !showMeetingModal) {
      const timer = setInterval(() => {
        setCountdown(prev => {
          if (prev <= 1) {
            fetchAllData();
            return AUTO_REFRESH_INTERVAL;
          }
          return prev - 1;
        });
      }, 1000);
      return () => clearInterval(timer);
    }
  }, [autoRefresh, showMeetingModal]);

  useEffect(() => {
    fetchTasks();
  }, [taskType, taskStatus]);

  const fetchAllData = async () => {
    try {
      setLoading(true);
      await Promise.all([
        fetchStats(),
        fetchOnlineUsers(),
        fetchUsersList(),
        fetchTasks(),
        fetchResources()
      ]);
      setError('');
    } catch (err) {
      console.error('获取数据失败:', err);
      setError('加载数据失败，请稍后重试');
    } finally {
      setLoading(false);
    }
  };

  const fetchStats = async () => {
    try {
      const response = await apiClient.get(buildApiUrl(API_ENDPOINTS.ADMIN.DASHBOARD_STATS));
      if (response.code === '200') {
        setStats(response.data);
      }
    } catch (err) {
      console.error('获取统计数据失败:', err);
    }
  };

  const fetchOnlineUsers = async () => {
    try {
      const response = await apiClient.get(buildApiUrl(API_ENDPOINTS.ADMIN.ONLINE_USERS));
      if (response.code === '200') {
        setOnlineUsers(response.data.users || []);
      }
    } catch (err) {
      console.error('获取在线用户失败:', err);
    }
  };

  const fetchUsersList = async () => {
    try {
      const response = await apiClient.get(buildApiUrl(API_ENDPOINTS.ADMIN.USER_STATS));
      if (response.code === '200') {
        setUsersList(response.data.users || []);
      }
    } catch (err) {
      console.error('获取用户列表失败:', err);
    }
  };

  const fetchTasks = async () => {
    try {
      const params = new URLSearchParams();
      if (taskType !== 'all') params.append('task_type', taskType);
      if (taskStatus !== 'all') params.append('status', taskStatus);
      params.append('limit', '20');

      const url = `${API_ENDPOINTS.ADMIN.TASKS_MONITOR}?${params.toString()}`;
      const response = await apiClient.get(buildApiUrl(url));
      if (response.code === '200') {
        setTasks(response.data.tasks || []);
      }
    } catch (err) {
      console.error('获取任务列表失败:', err);
    }
  };

  const fetchResources = async () => {
    try {
      const response = await apiClient.get(buildApiUrl(API_ENDPOINTS.ADMIN.SYSTEM_RESOURCES));
      if (response.code === '200') {
        setResources(response.data);
      }
    } catch (err) {
      console.error('获取系统资源失败:', err);
    }
  };

  const handleKickUser = async () => {
    try {
      const response = await apiClient.post(buildApiUrl(API_ENDPOINTS.ADMIN.KICK_USER(kickConfirmInfo.user_id)));
      if (response.code === '200') {
        showToast('用户已被踢出', 'success');
        fetchOnlineUsers();
      } else {
        showToast(`踢出失败: ${response.message}`, 'error');
      }
    } catch (err) {
      console.error('踢出用户失败:', err);
      showToast('踢出用户失败', 'error');
    } finally {
      setKickConfirmInfo(null);
    }
  };

  const handleViewMeeting = async (meetingId) => {
    if (!meetingId) return;
    setMeetingLoading(true);
    setShowMeetingModal(true);
    setMeetingDetails(null); // Clear previous
    
    try {
      const response = await apiClient.get(buildApiUrl(API_ENDPOINTS.MEETINGS.DETAIL(meetingId)));
      if (response.code === '200') {
        setMeetingDetails(response.data);
      } else {
        showToast('获取会议详情失败', 'error');
      }
    } catch (err) {
      console.error('Fetch meeting details error:', err);
      showToast('获取会议详情失败', 'error');
    } finally {
      setMeetingLoading(false);
    }
  };

  if (loading && !stats) {
    return <PageLoading message="加载中..." />;
  }

  return (
    <div className="admin-dashboard">
      {/* 顶部导航栏 - 使用与普通Dashboard一致的样式 */}
      <div className="dashboard-header">
        <div className="header-content">
          <div className="logo">
            <Waves size={32} className="logo-icon" />
            <span>管理面板</span>
          </div>
          <div className="user-actions">
            <button
              className={`auto-refresh-toggle ${autoRefresh ? 'active' : ''}`}
              onClick={() => setAutoRefresh(!autoRefresh)}
              title={autoRefresh ? '关闭自动刷新' : '开启自动刷新'}
            >
              <RefreshCw size={16} />
              {autoRefresh ? '自动刷新' : '手动刷新'}
            </button>
            <Dropdown
              trigger={
                <div className="user-menu-trigger">
                  {user.avatar_url ? (
                    <img 
                      src={user.avatar_url.startsWith('http') ? user.avatar_url : `${apiClient.defaults.baseURL || ''}${user.avatar_url}`} 
                      alt={user.caption}
                      style={{ 
                        width: '24px', 
                        height: '24px', 
                        borderRadius: '50%', 
                        objectFit: 'cover',
                        border: '1px solid #e2e8f0'
                      }}
                    />
                  ) : (
                    <User size={20} />
                  )}
                  <span>{user.caption}</span>
                  <ChevronDown size={16} />
                </div>
              }
              items={userMenus.map(menu => getMenuItemConfig(menu))}
            />
          </div>
        </div>
      </div>

      {/* Dashboard Content */}
      <div className="dashboard-content">
        {error && <div className="error-message">{error}</div>}

        {/* 统计卡片 */}
        {stats && (
          <div className="stats-grid">
          {/* 用户统计 */}
          <div className="stat-card">
            <div className="stat-icon" style={{ background: 'linear-gradient(135deg, #667eea 0%, #764ba2 100%)' }}>
              <Users size={24} />
            </div>
            <div className="stat-content">
              <h3>用户统计</h3>
              <div className="stat-number">{stats.users.total}</div>
              <div className="stat-details">
                <span>今日新增: {stats.users.today_new}</span>
                <span>在线: {stats.users.online}</span>
              </div>
            </div>
          </div>

          {/* 会议统计 */}
          <div className="stat-card">
            <div className="stat-icon" style={{ background: 'linear-gradient(135deg, #f093fb 0%, #f5576c 100%)' }}>
              <Activity size={24} />
            </div>
            <div className="stat-content">
              <h3>会议统计</h3>
              <div className="stat-number">{stats.meetings.total}</div>
              <div className="stat-details">
                <span>今日新增: {stats.meetings.today_new}</span>
              </div>
            </div>
          </div>

          {/* 存储统计 */}
          <div className="stat-card">
            <div className="stat-icon" style={{ background: 'linear-gradient(135deg, #4facfe 0%, #00f2fe 100%)' }}>
              <HardDrive size={24} />
            </div>
            <div className="stat-content">
              <h3>存储统计</h3>
              <div className="stat-number">{stats.storage.audio_total_size_gb} GB</div>
              <div className="stat-details">
                <span>音频文件: {stats.storage.audio_files_count} 个</span>
              </div>
            </div>
          </div>

          {/* 服务器资源 */}
          {resources && (
            <div className="stat-card">
              <div className="stat-icon" style={{ background: 'linear-gradient(135deg, #fa709a 0%, #fee140 100%)' }}>
                <Server size={24} />
              </div>
              <div className="stat-content">
                <h3>服务器资源</h3>
                <div className="resource-bars">
                  <div className="resource-item">
                    <Cpu size={14} />
                    <div className="resource-bar">
                      <div className="resource-fill" style={{ width: `${resources.cpu.percent}%` }}></div>
                    </div>
                    <span>{resources.cpu.percent}%</span>
                  </div>
                  <div className="resource-item">
                    <MemoryStick size={14} />
                    <div className="resource-bar">
                      <div className="resource-fill" style={{ width: `${resources.memory.percent}%` }}></div>
                    </div>
                    <span>{resources.memory.percent}%</span>
                  </div>
                  <div className="resource-item">
                    <HardDrive size={14} />
                    <div className="resource-bar">
                      <div className="resource-fill" style={{ width: `${resources.disk.percent}%` }}></div>
                    </div>
                    <span>{resources.disk.percent}%</span>
                  </div>
                </div>
              </div>
            </div>
          )}
          </div>
        )}

        {/* 任务统计 */}
        {stats && (
          <div className="tasks-overview">
          <h2>任务概览</h2>
          <div className="task-stats-grid">
            <div className="task-stat-card">
              <h3>转录任务</h3>
              <div className="task-stat-numbers">
                <div className="task-stat-item">
                  <span className="task-stat-label">进行中</span>
                  <span className="task-stat-value running">{stats.tasks.transcription.running}</span>
                </div>
                <div className="task-stat-item">
                  <span className="task-stat-label">已完成</span>
                  <span className="task-stat-value completed">{stats.tasks.transcription.completed}</span>
                </div>
                <div className="task-stat-item">
                  <span className="task-stat-label">失败</span>
                  <span className="task-stat-value failed">{stats.tasks.transcription.failed}</span>
                </div>
              </div>
            </div>

            <div className="task-stat-card">
              <h3>总结任务</h3>
              <div className="task-stat-numbers">
                <div className="task-stat-item">
                  <span className="task-stat-label">进行中</span>
                  <span className="task-stat-value running">{stats.tasks.summary.running}</span>
                </div>
                <div className="task-stat-item">
                  <span className="task-stat-label">已完成</span>
                  <span className="task-stat-value completed">{stats.tasks.summary.completed}</span>
                </div>
                <div className="task-stat-item">
                  <span className="task-stat-label">失败</span>
                  <span className="task-stat-value failed">{stats.tasks.summary.failed}</span>
                </div>
              </div>
            </div>

            <div className="task-stat-card">
              <h3>知识库任务</h3>
              <div className="task-stat-numbers">
                <div className="task-stat-item">
                  <span className="task-stat-label">进行中</span>
                  <span className="task-stat-value running">{stats.tasks.knowledge_base.running}</span>
                </div>
                <div className="task-stat-item">
                  <span className="task-stat-label">已完成</span>
                  <span className="task-stat-value completed">{stats.tasks.knowledge_base.completed}</span>
                </div>
                <div className="task-stat-item">
                  <span className="task-stat-label">失败</span>
                  <span className="task-stat-value failed">{stats.tasks.knowledge_base.failed}</span>
                </div>
              </div>
            </div>
          </div>
          </div>
        )}

        {/* 用户列表 */}
        <div className="admin-panel full-width">
          <div className="panel-header">
            <h2>用户列表 ({usersList.length})</h2>
          </div>
          <div className="panel-content">
            {usersList.length === 0 ? (
              <div className="empty-state">暂无用户数据</div>
            ) : (
              <table className="users-table">
                <thead>
                  <tr>
                    <th>ID</th>
                    <th>用户名</th>
                    <th>姓名</th>
                    <th>注册时间</th>
                    <th>最新登录时间</th>
                    <th>会议数量</th>
                    <th>会议时长</th>
                  </tr>
                </thead>
                <tbody>
                  {usersList.map(u => (
                    <tr key={u.user_id}>
                      <td>{u.user_id}</td>
                      <td>{u.username}</td>
                      <td>{u.caption}</td>
                      <td>{u.created_at ? new Date(u.created_at).toLocaleString('zh-CN') : '-'}</td>
                      <td>{u.last_login_time ? new Date(u.last_login_time).toLocaleString('zh-CN') : '-'}</td>
                      <td>{u.meeting_count || 0}</td>
                      <td>{u.total_duration_formatted || '-'}</td>
                    </tr>
                  ))}
                </tbody>
              </table>
            )}
          </div>
        </div>

        <div className="admin-content-grid">
        {/* 在线用户列表 */}
        <div className="admin-panel">
          <div className="panel-header">
            <h2>在线用户 ({onlineUsers.length})</h2>
          </div>
          <div className="panel-content">
            {onlineUsers.length === 0 ? (
              <div className="empty-state">暂无在线用户</div>
            ) : (
              <table className="online-users-table">
                <thead>
                  <tr>
                    <th>ID</th>
                    <th>用户名</th>
                    <th>姓名</th>
                    <th>会话数</th>
                    <th>剩余时间</th>
                    <th>操作</th>
                  </tr>
                </thead>
                <tbody>
                  {onlineUsers.map(u => (
                    <tr key={u.user_id}>
                      <td>{u.user_id}</td>
                      <td>{u.username}</td>
                      <td>{u.caption}</td>
                      <td>{u.token_count}</td>
                      <td>{u.ttl_hours}h</td>
                      <td>
                        <button
                          className="kick-btn"
                          onClick={() => setKickConfirmInfo(u)}
                          title="踢出用户"
                        >
                          <UserX size={16} />
                        </button>
                      </td>
                    </tr>
                  ))}
                </tbody>
              </table>
            )}
          </div>
        </div>

        {/* 任务监控 */}
        <div className="admin-panel">
          <div className="panel-header">
            <h2>任务监控</h2>
            <div className="panel-filters">
              <select value={taskType} onChange={(e) => setTaskType(e.target.value)}>
                <option value="all">全部类型</option>
                <option value="transcription">转录</option>
                <option value="summary">总结</option>
                <option value="knowledge_base">知识库</option>
              </select>
              <select value={taskStatus} onChange={(e) => setTaskStatus(e.target.value)}>
                <option value="all">全部状态</option>
                <option value="running">进行中</option>
                <option value="completed">已完成</option>
                <option value="failed">失败</option>
              </select>
            </div>
          </div>
          <div className="panel-content">
            {tasks.length === 0 ? (
              <div className="empty-state">暂无任务</div>
            ) : (
              <table className="tasks-table">
                <thead>
                  <tr>
                    <th>任务ID</th>
                    <th>类型</th>
                    <th>关联对象</th>
                    <th>创建者</th>
                    <th>状态</th>
                    <th>进度</th>
                    <th>创建时间</th>
                  </tr>
                </thead>
                <tbody>
                  {tasks.map(task => (
                    <tr key={`${task.task_type}-${task.task_id}`}>
                      <td>{task.task_id}</td>
                      <td>{getTaskTypeText(task.task_type)}</td>
                      <td>
                        <div style={{ display: 'flex', alignItems: 'center', gap: '8px' }}>
                          {task.meeting_id && task.task_type === 'transcription' && (
                            <button 
                              type="button"
                              className="btn-icon" 
                              onClick={(e) => {
                                e.stopPropagation();
                                handleViewMeeting(task.meeting_id);
                              }}
                              title="查看详情"
                              style={{ padding: '4px', height: 'auto', width: 'auto', border: 'none', background: 'transparent', cursor: 'pointer', color: '#667eea' }}
                            >
                              <Search size={16} />
                            </button>
                          )}
                          <span>{task.meeting_title || '-'}</span>
                        </div>
                      </td>
                      <td>{task.creator_name || '-'}</td>
                      <td>
                        <span className={getStatusBadgeClass(task.status)}>
                          {getStatusText(task.status)}
                        </span>
                      </td>
                      <td>
                        {task.progress !== null ? `${task.progress}%` : '-'}
                      </td>
                      <td>{new Date(task.created_at).toLocaleString()}</td>
                    </tr>
                  ))}
                </tbody>
              </table>
            )}
          </div>
        </div>
        </div>
      </div>

      {/* 踢出用户确认对话框 */}
      <ConfirmDialog
        isOpen={!!kickConfirmInfo}
        onClose={() => setKickConfirmInfo(null)}
        onConfirm={handleKickUser}
        title="踢出用户"
        message={`确定要踢出用户"${kickConfirmInfo?.caption}"吗？该用户将被强制下线。`}
        confirmText="确定踢出"
        cancelText="取消"
        type="warning"
      />

      {/* 会议数据模态框 (使用标准 FormModal) */}
      <FormModal
        isOpen={showMeetingModal}
        onClose={() => setShowMeetingModal(false)}
        title="会议数据"
        size="medium"
        actions={
          <button className="btn btn-secondary" onClick={() => setShowMeetingModal(false)}>关闭</button>
        }
      >
        {meetingLoading ? (
          <div className="modal-body-loading">
            <div className="loading-spinner"></div>
            <p>正在获取会议数据...</p>
          </div>
        ) : meetingDetails ? (
          <div className="meeting-details-info">
            <div className="detail-item">
              <span className="detail-label">会议名称:</span>
              <span className="detail-value">{meetingDetails.title}</span>
            </div>
            <div className="detail-item">
              <span className="detail-label">开始时间:</span>
              <span className="detail-value">
                {meetingDetails.meeting_time ? new Date(meetingDetails.meeting_time).toLocaleString() : '-'}
              </span>
            </div>
            <div className="detail-item">
              <span className="detail-label">使用模版:</span>
              <span className="detail-value">{meetingDetails.prompt_name || '默认模版'}</span>
            </div>
            <div className="detail-item">
              <span className="detail-label">音频信息:</span>
              <div className="detail-value" style={{ display: 'flex', alignItems: 'center', gap: '10px' }}>
                {meetingDetails.audio_file_path && meetingDetails.audio_file_path.length > 5 ? (
                  <>
                    <span>{meetingDetails.audio_duration ? `${Math.floor(meetingDetails.audio_duration / 60)}分${Math.floor(meetingDetails.audio_duration % 60)}秒` : '未知时长'}</span>
                    <a 
                      href={meetingDetails.audio_file_path.startsWith('http') ? meetingDetails.audio_file_path : `${apiClient.defaults.baseURL || ''}/${meetingDetails.audio_file_path.replace(/^\//, '')}`} 
                      target="_blank" 
                      rel="noopener noreferrer"
                      style={{ color: '#3b82f6', textDecoration: 'underline', cursor: 'pointer' }}
                    >
                      下载
                    </a>
                  </>
                ) : (
                  <span style={{ color: '#94a3b8' }}>无音频</span>
                )}
              </div>
            </div>
          </div>
        ) : (
          <div className="empty-state">无法加载数据</div>
        )}
      </FormModal>

      {/* Toast notifications */}
      {toasts.map(toast => (
        <Toast
          key={toast.id}
          message={toast.message}
          type={toast.type}
          onClose={() => removeToast(toast.id)}
        />
      ))}
    </div>
  );
};

export default AdminDashboard;