import React, { useState, useEffect, useCallback } from 'react';
import { adminAPI } from '@/api';

const styles: Record<string, React.CSSProperties> = {
  container: { padding: 24, backgroundColor: '#f5f7fa', minHeight: '100vh' },
  header: { display: 'flex', justifyContent: 'space-between', alignItems: 'center', marginBottom: 24 },
  title: { fontSize: 24, fontWeight: 700, color: '#1A1F36' },
  addBtn: { padding: '10px 24px', backgroundColor: '#4f46e5', color: '#fff', border: 'none', borderRadius: 8, cursor: 'pointer', fontSize: 14, fontWeight: 600 },
  statsRow: { display: 'grid', gridTemplateColumns: 'repeat(auto-fit, minmax(200px, 1fr))', gap: 16, marginBottom: 24 },
  statCard: { backgroundColor: '#fff', padding: 20, borderRadius: 12, boxShadow: '0 1px 3px rgba(0,0,0,0.08)' },
  statLabel: { fontSize: 13, color: '#6b7280', marginBottom: 8 },
  statValue: { fontSize: 28, fontWeight: 700, color: '#1A1F36' },
  toolbar: { display: 'flex', gap: 12, marginBottom: 16, flexWrap: 'wrap' as const },
  searchInput: { padding: '8px 16px', border: '1px solid #e5e7eb', borderRadius: 8, fontSize: 14, width: 250 },
  filterSelect: { padding: '8px 12px', border: '1px solid #e5e7eb', borderRadius: 8, fontSize: 14, backgroundColor: '#fff' },
  table: { width: '100%', borderCollapse: 'collapse' as const, backgroundColor: '#fff', borderRadius: 12, overflow: 'hidden', boxShadow: '0 1px 3px rgba(0,0,0,0.08)' },
  th: { padding: '12px 16px', textAlign: 'left' as const, fontSize: 13, fontWeight: 600, color: '#6b7280', backgroundColor: '#f9fafb', borderBottom: '1px solid #e5e7eb' },
  td: { padding: '12px 16px', fontSize: 14, color: '#374151', borderBottom: '1px solid #f3f4f6' },
  badge: { display: 'inline-block', padding: '2px 10px', borderRadius: 20, fontSize: 12, fontWeight: 600 },
  actionBtn: { padding: '4px 12px', border: '1px solid #e5e7eb', borderRadius: 6, fontSize: 13, cursor: 'pointer', marginRight: 6, backgroundColor: '#fff' },
  pagination: { display: 'flex', justifyContent: 'center', gap: 8, marginTop: 20 },
  pageBtn: { padding: '8px 16px', border: '1px solid #e5e7eb', borderRadius: 6, cursor: 'pointer', backgroundColor: '#fff', fontSize: 14 },
  modalOverlay: { position: 'fixed' as const, top: 0, left: 0, right: 0, bottom: 0, backgroundColor: 'rgba(0,0,0,0.5)', display: 'flex', justifyContent: 'center', alignItems: 'center', zIndex: 1000 },
  modal: { backgroundColor: '#fff', borderRadius: 16, padding: 32, width: 560, maxHeight: '80vh', overflow: 'auto', boxShadow: '0 20px 60px rgba(0,0,0,0.15)' },
  modalTitle: { fontSize: 18, fontWeight: 700, marginBottom: 24, color: '#1A1F36' },
  formGroup: { marginBottom: 16 },
  label: { display: 'block', fontSize: 13, fontWeight: 600, color: '#374151', marginBottom: 6 },
  input: { width: '100%', padding: '10px 12px', border: '1px solid #e5e7eb', borderRadius: 8, fontSize: 14, boxSizing: 'border-box' as const },
  textarea: { width: '100%', padding: '10px 12px', border: '1px solid #e5e7eb', borderRadius: 8, fontSize: 14, minHeight: 80, resize: 'vertical' as const, boxSizing: 'border-box' as const },
  modalActions: { display: 'flex', justifyContent: 'flex-end', gap: 12, marginTop: 24 },
  cancelBtn: { padding: '10px 24px', border: '1px solid #e5e7eb', borderRadius: 8, cursor: 'pointer', backgroundColor: '#fff', fontSize: 14 },
  submitBtn: { padding: '10px 24px', backgroundColor: '#4f46e5', color: '#fff', border: 'none', borderRadius: 8, cursor: 'pointer', fontSize: 14, fontWeight: 600 },
  toast: { position: 'fixed' as const, top: 20, right: 20, padding: '12px 24px', borderRadius: 8, fontSize: 14, fontWeight: 600, zIndex: 2000, color: '#fff' },
  detailsGrid: { display: 'grid', gridTemplateColumns: '1fr 1fr', gap: 12, marginTop: 16 },
  detailsItem: { fontSize: 13 },
  detailsLabel: { color: '#6b7280', marginBottom: 4 },
};

const TRANSPORT_TYPES = [
  { value: '', label: '全部类型' },
  { value: 'stdio', label: 'STDIO' },
  { value: 'sse', label: 'SSE' },
  { value: 'streamable_http', label: 'HTTP 流式' },
];

const STATUS_TYPES = [
  { value: '', label: '全部状态' },
  { value: 'connected', label: '已连接' },
  { value: 'disconnected', label: '未连接' },
  { value: 'error', label: '错误' },
];

interface MCPServer {
  id: string;
  name: string;
  description: string;
  transport_type: string;
  transport_type_label: string;
  command: string;
  args: Record<string, any>;
  env_vars: Record<string, string>;
  url: string;
  headers: Record<string, string>;
  is_enabled: boolean;
  status: string;
  last_connected_at: string;
  tools_count: number;
  resources_count: number;
  created_at: string;
  updated_at: string;
}

export default function AdminMcp() {
  const [servers, setServers] = useState<MCPServer[]>([]);
  const [stats, setStats] = useState<any>({});
  const [loading, setLoading] = useState(true);
  const [page, setPage] = useState(1);
  const [total, setTotal] = useState(0);
  const [search, setSearch] = useState('');
  const [filterTransport, setFilterTransport] = useState('');
  const [filterStatus, setFilterStatus] = useState('');
  const [showModal, setShowModal] = useState(false);
  const [editingServer, setEditingServer] = useState<MCPServer | null>(null);
  const [toast, setToast] = useState<{ message: string; type: string } | null>(null);
  const pageSize = 20;

  const showToast = (message: string, type: string = 'success') => {
    setToast({ message, type });
    setTimeout(() => setToast(null), 3000);
  };

  const fetchStats = useCallback(async () => {
    try {
      const result = await adminAPI.getAdminMcpStats() as any;
      if (result.code === 0) setStats(result.data);
    } catch (e) { /* ignore */ }
  }, []);

  const fetchServers = useCallback(async () => {
    setLoading(true);
    try {
      const params: any = { page, page_size: pageSize };
      if (search) params.search = search;
      if (filterTransport) params.transport_type = filterTransport;
      if (filterStatus) params.status = filterStatus;
      const result = await adminAPI.getAdminMcpServers(params) as any;
      if (result.code === 0) {
        setServers(result.data.items || []);
        setTotal(result.data.total || 0);
      }
    } catch (e) {
      showToast('加载服务失败', 'error');
    } finally {
      setLoading(false);
    }
  }, [page, search, filterTransport, filterStatus]);

  useEffect(() => {
    fetchStats();
    fetchServers();
  }, [fetchStats, fetchServers]);

  const handleCreate = () => {
    setEditingServer(null);
    setShowModal(true);
  };

  const handleEdit = (server: MCPServer) => {
    setEditingServer(server);
    setShowModal(true);
  };

  const handleDelete = async (server: MCPServer) => {
    if (!confirm(`确认删除 MCP 服务 "${server.name}"？`)) return;
    try {
      await adminAPI.deleteAdminMcpServer(server.id);
      showToast('服务已删除');
      fetchServers();
      fetchStats();
    } catch (e) {
      showToast('删除失败', 'error');
    }
  };

  const handleToggle = async (server: MCPServer) => {
    try {
      await adminAPI.toggleAdminMcpServer(server.id);
      showToast(server.is_enabled ? '已禁用' : '已启用');
      fetchServers();
      fetchStats();
    } catch (e) {
      showToast('切换失败', 'error');
    }
  };

  const handleTest = async (server: MCPServer) => {
    try {
      const result = await adminAPI.testAdminMcpServer(server.id) as any;
      if (result.code === 0) {
        showToast(result.data.success ? '连接成功' : `连接失败：${result.data.message}`, result.data.success ? 'success' : 'error');
        fetchServers();
        fetchStats();
      }
    } catch (e) {
      showToast('测试失败', 'error');
    }
  };

  const handleSubmit = async (formData: any) => {
    try {
      if (editingServer) {
        await adminAPI.updateAdminMcpServer(editingServer.id, formData);
        showToast('服务已更新');
      } else {
        await adminAPI.createAdminMcpServer(formData);
        showToast('服务已创建');
      }
      setShowModal(false);
      fetchServers();
      fetchStats();
    } catch (e: any) {
      showToast(e.message || '操作失败', 'error');
    }
  };

  const getStatusBadge = (status: string) => {
    const labels: Record<string, string> = { connected: '已连接', disconnected: '未连接', error: '错误' };
    const colors: Record<string, { bg: string; color: string }> = {
      connected: { bg: '#dcfce7', color: '#166534' },
      disconnected: { bg: '#f3f4f6', color: '#6b7280' },
      error: { bg: '#fee2e2', color: '#991b1b' },
    };
    const c = colors[status] || colors.disconnected;
    return <span style={{ ...styles.badge, backgroundColor: c.bg, color: c.color }}>{labels[status] || status}</span>;
  };

  const getTransportBadge = (type: string) => {
    const labels: Record<string, string> = { sse: 'SSE', stdio: '标准IO', streamable_http: 'HTTP 流式' };
    const c = type === 'sse' ? { bg: '#e0e7ff', color: '#3730a3' } : type === 'streamable_http' ? { bg: '#d1fae5', color: '#065f46' } : { bg: '#fef3c7', color: '#92400e' };
    return <span style={{ ...styles.badge, backgroundColor: c.bg, color: c.color }}>{labels[type] || type}</span>;
  };

  const totalPages = Math.ceil(total / pageSize);

  return (
    <div style={styles.container}>
      {toast && (
        <div style={{ ...styles.toast, backgroundColor: toast.type === 'error' ? '#ef4444' : '#10b981' }}>
          {toast.message}
        </div>
      )}

      <div style={styles.header}>
        <h1 style={styles.title}>MCP 服务管理</h1>
        {/* 手动添加服务入口已移除：MCP 仅支持通过 URL 导入（见应用市场「导入」）或由 AI 聊天自动部署安装 */}
      </div>

      <div style={styles.statsRow}>
        <div style={styles.statCard}>
          <div style={styles.statLabel}>服务总数</div>
          <div style={styles.statValue}>{stats.total_servers || 0}</div>
        </div>
        <div style={styles.statCard}>
          <div style={styles.statLabel}>已启用</div>
          <div style={styles.statValue}>{stats.enabled_servers || 0}</div>
        </div>
        <div style={styles.statCard}>
          <div style={styles.statLabel}>已连接</div>
          <div style={{ ...styles.statValue, color: '#10b981' }}>{stats.connected_servers || 0}</div>
        </div>
        <div style={styles.statCard}>
          <div style={styles.statLabel}>传输方式分布</div>
          <div style={{ fontSize: 13, color: '#374151' }}>
            {Object.entries(stats.by_transport || {}).map(([k, v]) => (
              <span key={k} style={{ marginRight: 12 }}>{k}: {v as number}</span>
            ))}
          </div>
        </div>
      </div>

      <div style={styles.toolbar}>
        <input
          style={styles.searchInput}
          placeholder="搜索服务..."
          value={search}
          onChange={e => { setSearch(e.target.value); setPage(1); }}
        />
        <select style={styles.filterSelect} value={filterTransport} onChange={e => { setFilterTransport(e.target.value); setPage(1); }}>
          {TRANSPORT_TYPES.map(t => <option key={t.value} value={t.value}>{t.label}</option>)}
        </select>
        <select style={styles.filterSelect} value={filterStatus} onChange={e => { setFilterStatus(e.target.value); setPage(1); }}>
          {STATUS_TYPES.map(s => <option key={s.value} value={s.value}>{s.label}</option>)}
        </select>
      </div>

      <table style={styles.table}>
        <thead>
          <tr>
            <th style={styles.th}>名称</th>
            <th style={styles.th}>传输方式</th>
            <th style={styles.th}>状态</th>
            <th style={styles.th}>工具数</th>
            <th style={styles.th}>最后连接</th>
            <th style={styles.th}>启用</th>
            <th style={styles.th}>操作</th>
          </tr>
        </thead>
        <tbody>
          {loading ? (
            <tr><td colSpan={7} style={{ ...styles.td, textAlign: 'center', padding: 40 }}>加载中...</td></tr>
          ) : servers.length === 0 ? (
            <tr><td colSpan={7} style={{ ...styles.td, textAlign: 'center', padding: 40, color: '#9ca3af' }}>未找到 MCP 服务</td></tr>
          ) : servers.map(s => (
            <tr key={s.id}>
              <td style={styles.td}>
                <div style={{ fontWeight: 600 }}>{s.name}</div>
                <div style={{ fontSize: 12, color: '#9ca3af' }}>{s.description?.substring(0, 50)}{s.description?.length > 50 ? '...' : ''}</div>
              </td>
              <td style={styles.td}>{getTransportBadge(s.transport_type)}</td>
              <td style={styles.td}>{getStatusBadge(s.status)}</td>
              <td style={styles.td}>{s.tools_count || '-'}</td>
              <td style={styles.td}>{s.last_connected_at ? new Date(s.last_connected_at).toLocaleString() : '从未'}</td>
              <td style={styles.td}>
                <span style={{ ...styles.badge, backgroundColor: s.is_enabled ? '#dcfce7' : '#f3f4f6', color: s.is_enabled ? '#166534' : '#6b7280' }}>
                  {s.is_enabled ? '是' : '否'}
                </span>
              </td>
              <td style={styles.td}>
                <button style={styles.actionBtn} onClick={() => handleEdit(s)}>编辑</button>
                <button style={{ ...styles.actionBtn, color: s.is_enabled ? '#ef4444' : '#10b981' }} onClick={() => handleToggle(s)}>
                  {s.is_enabled ? '禁用' : '启用'}
                </button>
                <button style={{ ...styles.actionBtn, color: '#4f46e5' }} onClick={() => handleTest(s)}>测试</button>
                <button style={{ ...styles.actionBtn, color: '#ef4444' }} onClick={() => handleDelete(s)}>删除</button>
              </td>
            </tr>
          ))}
        </tbody>
      </table>

      {totalPages > 1 && (
        <div style={styles.pagination}>
          <button style={styles.pageBtn} disabled={page <= 1} onClick={() => setPage(p => p - 1)}>上一页</button>
          <span style={{ padding: '8px 12px', fontSize: 14 }}>第 {page} / {totalPages} 页</span>
          <button style={styles.pageBtn} disabled={page >= totalPages} onClick={() => setPage(p => p + 1)}>下一页</button>
        </div>
      )}

      {showModal && <McpModal server={editingServer} onSubmit={handleSubmit} onClose={() => setShowModal(false)} />}
    </div>
  );
}

function McpModal({ server, onSubmit, onClose }: { server: MCPServer | null; onSubmit: (data: any) => void; onClose: () => void }) {
  const [form, setForm] = useState({
    name: server?.name || '',
    description: server?.description || '',
    transport_type: server?.transport_type || 'stdio',
    command: server?.command || '',
    args: server?.args ? JSON.stringify(server.args, null, 2) : '',
    env_vars: server?.env_vars ? JSON.stringify(server.env_vars, null, 2) : '',
    url: server?.url || '',
    headers: server?.headers ? JSON.stringify(server.headers, null, 2) : '',
  });

  const handleChange = (field: string, value: string) => {
    setForm(prev => ({ ...prev, [field]: value }));
  };

  const handleSubmit = (e: React.FormEvent) => {
    e.preventDefault();
    const data: any = {
      name: form.name,
      description: form.description,
      transport_type: form.transport_type,
    };

    if (form.transport_type === 'stdio') {
      data.command = form.command;
      try { data.args = form.args ? JSON.parse(form.args) : {}; } catch { data.args = {}; }
      try { data.env_vars = form.env_vars ? JSON.parse(form.env_vars) : {}; } catch { data.env_vars = {}; }
    } else {
      data.url = form.url;
      try { data.headers = form.headers ? JSON.parse(form.headers) : {}; } catch { data.headers = {}; }
    }

    onSubmit(data);
  };

  return (
    <div style={styles.modalOverlay} onClick={onClose}>
      <div style={styles.modal} onClick={e => e.stopPropagation()}>
        <div style={styles.modalTitle}>{server ? '编辑 MCP 服务' : '添加 MCP 服务'}</div>
        <form onSubmit={handleSubmit}>
          <div style={styles.formGroup}>
            <label style={styles.label}>名称 *</label>
            <input style={styles.input} value={form.name} onChange={e => handleChange('name', e.target.value)} required placeholder="例如：文件系统服务" />
          </div>
          <div style={styles.formGroup}>
            <label style={styles.label}>描述</label>
            <textarea style={styles.textarea} value={form.description} onChange={e => handleChange('description', e.target.value)} placeholder="可选描述信息" />
          </div>
          <div style={styles.formGroup}>
            <label style={styles.label}>传输类型</label>
            <select style={{ ...styles.input, width: '100%' }} value={form.transport_type} onChange={e => handleChange('transport_type', e.target.value)}>
              <option value="stdio">STDIO（命令行方式）</option>
              <option value="sse">SSE（HTTP 方式）</option>
            </select>
          </div>

          {form.transport_type === 'stdio' ? (
            <>
              <div style={styles.formGroup}>
                <label style={styles.label}>命令</label>
                <input style={styles.input} value={form.command} onChange={e => handleChange('command', e.target.value)} placeholder="例如：npx @modelcontextprotocol/server-filesystem" />
              </div>
              <div style={styles.formGroup}>
                <label style={styles.label}>参数（JSON）</label>
                <textarea style={styles.textarea} value={form.args} onChange={e => handleChange('args', e.target.value)} placeholder='["/path/to/allowed"]' />
              </div>
              <div style={styles.formGroup}>
                <label style={styles.label}>环境变量（JSON）</label>
                <textarea style={styles.textarea} value={form.env_vars} onChange={e => handleChange('env_vars', e.target.value)} placeholder='{"KEY": "value"}' />
              </div>
            </>
          ) : (
            <>
              <div style={styles.formGroup}>
                <label style={styles.label}>SSE 地址</label>
                <input style={styles.input} value={form.url} onChange={e => handleChange('url', e.target.value)} placeholder="http://localhost:3001/sse" />
              </div>
              <div style={styles.formGroup}>
                <label style={styles.label}>请求头（JSON）</label>
                <textarea style={styles.textarea} value={form.headers} onChange={e => handleChange('headers', e.target.value)} placeholder='{"Authorization": "Bearer ..."}' />
              </div>
            </>
          )}

          <div style={styles.modalActions}>
            <button type="button" style={styles.cancelBtn} onClick={onClose}>取消</button>
            <button type="submit" style={styles.submitBtn}>{server ? '更新' : '创建'}</button>
          </div>
        </form>
      </div>
    </div>
  );
}