import { useEffect, useState } from 'react'
import { Table, Tag, Card, Row, Col, Statistic, Button, Modal, Space, Descriptions } from 'antd'
import { AlertOutlined, InfoCircleOutlined, ReloadOutlined } from '@ant-design/icons'
import { useAuthStore } from '../../stores/auth'
import AppLayout from '../../components/AppLayout/AppLayout'

interface Alert {
  id: number
  severity: 'critical' | 'warning' | 'info'
  status: 'active' | 'acknowledged' | 'resolved'
  datasource_name: string
  message: string
  created_at: string
  acknowledged_at?: string
  resolved_at?: string
}

function Alerts() {
  const { token } = useAuthStore()
  const [alerts, setAlerts] = useState<Alert[]>([])
  const [loading, setLoading] = useState(false)
  const [selectedAlert, setSelectedAlert] = useState<Alert | null>(null)
  const [detailVisible, setDetailVisible] = useState(false)

  const fetchAlerts = async () => {
    setLoading(true)
    try {
      const res = await fetch('/api/v1/alerts', {
        headers: { Authorization: `Bearer ${token}` },
      })
      const data = await res.json()
      setAlerts(data.data || [])
    } catch (error) {
      console.error('Failed to fetch alerts:', error)
    } finally {
      setLoading(false)
    }
  }

  useEffect(() => {
    fetchAlerts()
  }, [token])

  const handleAcknowledge = async (alertId: number) => {
    try {
      await fetch(`/api/v1/alerts/${alertId}/acknowledge`, {
        method: 'POST',
        headers: { Authorization: `Bearer ${token}` },
      })
      fetchAlerts()
    } catch (error) {
      console.error('Failed to acknowledge alert:', error)
    }
  }

  const handleResolve = async (alertId: number) => {
    try {
      await fetch(`/api/v1/alerts/${alertId}/resolve`, {
        method: 'POST',
        headers: { Authorization: `Bearer ${token}` },
        body: JSON.stringify({ resolution: '已处理' }),
      })
      fetchAlerts()
    } catch (error) {
      console.error('Failed to resolve alert:', error)
    }
  }

  const columns = [
    { title: 'ID', dataIndex: 'id', key: 'id', width: 60 },
    {
      title: '级别',
      dataIndex: 'severity',
      key: 'severity',
      render: (s: string) => {
        const colors: Record<string, string> = { critical: 'error', warning: 'warning', info: 'blue' }
        const icons: Record<string, JSX.Element> = {
          critical: <AlertOutlined />,
          warning: <AlertOutlined />,
          info: <InfoCircleOutlined />,
        }
        return (
          <Tag color={colors[s]} icon={icons[s]}>
            {s === 'critical' ? '严重' : s === 'warning' ? '警告' : '信息'}
          </Tag>
        )
      },
    },
    {
      title: '状态',
      dataIndex: 'status',
      key: 'status',
      render: (s: string) => {
        const colors: Record<string, string> = { active: 'red', acknowledged: 'orange', resolved: 'green' }
        return (
          <Tag color={colors[s]}>
            {s === 'active' ? '待处理' : s === 'acknowledged' ? '已确认' : '已解决'}
          </Tag>
        )
      },
    },
    { title: '数据源', dataIndex: 'datasource_name', key: 'datasource_name' },
    { title: '消息', dataIndex: 'message', key: 'message', ellipsis: true },
    {
      title: '时间',
      dataIndex: 'created_at',
      key: 'created_at',
      render: (t: string) => new Date(t).toLocaleString('zh-CN'),
    },
    {
      title: '操作',
      key: 'action',
      render: (_: unknown, record: Alert) => (
        <Space>
          {record.status === 'active' && (
            <Button type="link" size="small" onClick={() => handleAcknowledge(record.id)}>
              确认
            </Button>
          )}
          {record.status !== 'resolved' && (
            <Button type="link" size="small" onClick={() => handleResolve(record.id)}>
              解决
            </Button>
          )}
          <Button type="link" size="small" onClick={() => { setSelectedAlert(record); setDetailVisible(true); }}>
            详情
          </Button>
        </Space>
      ),
    },
  ]

  const stats = alerts.reduce(
    (acc, alert) => {
      if (alert.status === 'active') {
        acc[alert.severity]++
      }
      return acc
    },
    { critical: 0, warning: 0, info: 0 } as Record<string, number>
  )

  return (
    <AppLayout>
      <Row gutter={[16, 16]} style={{ marginBottom: 16 }}>
        <Col span={8}>
          <Card>
            <Statistic
              title="严重告警"
              value={stats.critical}
              valueStyle={{ color: '#ff4d4f' }}
              prefix={<AlertOutlined />}
            />
          </Card>
        </Col>
        <Col span={8}>
          <Card>
            <Statistic
              title="警告"
              value={stats.warning}
              valueStyle={{ color: '#faad14' }}
              prefix={<AlertOutlined />}
            />
          </Card>
        </Col>
        <Col span={8}>
          <Card>
            <Statistic title="信息" value={stats.info} valueStyle={{ color: '#1890ff' }} prefix={<InfoCircleOutlined />} />
          </Card>
        </Col>
      </Row>

      <Card
        title="告警列表"
        extra={<Button icon={<ReloadOutlined />} onClick={fetchAlerts}>刷新</Button>}
      >
        <Table columns={columns} dataSource={alerts} rowKey="id" loading={loading} pagination={{ pageSize: 10 }} scroll={{ x: 'max-content' }} tableLayout="fixed" />
      </Card>

      <Modal
        title="告警详情"
        open={detailVisible}
        onCancel={() => setDetailVisible(false)}
        footer={null}
        width={600}
      >
        {selectedAlert && (
          <Descriptions column={1} bordered>
            <Descriptions.Item label="ID">{selectedAlert.id}</Descriptions.Item>
            <Descriptions.Item label="级别">
              <Tag color={selectedAlert.severity === 'critical' ? 'error' : selectedAlert.severity === 'warning' ? 'warning' : 'blue'}>
                {selectedAlert.severity}
              </Tag>
            </Descriptions.Item>
            <Descriptions.Item label="状态">
              <Tag color={selectedAlert.status === 'active' ? 'red' : selectedAlert.status === 'acknowledged' ? 'orange' : 'green'}>
                {selectedAlert.status}
              </Tag>
            </Descriptions.Item>
            <Descriptions.Item label="数据源">{selectedAlert.datasource_name}</Descriptions.Item>
            <Descriptions.Item label="消息">{selectedAlert.message}</Descriptions.Item>
            <Descriptions.Item label="创建时间">{new Date(selectedAlert.created_at).toLocaleString('zh-CN')}</Descriptions.Item>
            {selectedAlert.acknowledged_at && (
              <Descriptions.Item label="确认时间">
                {new Date(selectedAlert.acknowledged_at).toLocaleString('zh-CN')}
              </Descriptions.Item>
            )}
            {selectedAlert.resolved_at && (
              <Descriptions.Item label="解决时间">
                {new Date(selectedAlert.resolved_at).toLocaleString('zh-CN')}
              </Descriptions.Item>
            )}
          </Descriptions>
        )}
      </Modal>
    </AppLayout>
  )
}

export default Alerts
