import { useState, useEffect } from 'react';
import { Row, Col, Card, Descriptions, Spin, message, Typography } from 'antd';
import ReactEChartsCore from 'echarts-for-react/lib/core';
import { echarts } from '@/utils/echarts';
import { macarons } from '../../themes/macarons';
import { getCache } from '../../api/monitor/cache';
import type { CacheMonitorResponse } from '@/types/api';
import './cache-monitor.css';

const { Text } = Typography;

echarts.registerTheme('macarons', macarons);

const defaultCacheData: CacheMonitorResponse = {
  info: {},
  dbSize: 0,
  commandStats: [],
};

const toDisplayText = (value: string | number | undefined): string => {
  if (value === undefined || value === null) {
    return '';
  }
  return String(value);
};

const CacheMonitorPage = () => {
  const [loading, setLoading] = useState(true);
  const [cacheData, setCacheData] = useState<CacheMonitorResponse>(defaultCacheData);
  const [error, setError] = useState<string | null>(null);

  useEffect(() => {
    getCache()
      .then((response) => {
        setCacheData(response);
      })
      .catch(() => {
        const errorMsg = '加载缓存数据失败，请确认后端服务是否正常。';
        setError(errorMsg);
        message.error(errorMsg);
      })
      .finally(() => {
        setLoading(false);
      });
  }, []);

  if (loading) {
    return <Spin spinning={true} description="正在加载缓存监控数据..." style={{ display: 'block', marginTop: '50px' }} />;
  }

  if (error) {
    return <div style={{ textAlign: 'center', marginTop: '50px' }}><Text type="danger">{error}</Text></div>;
  }

  const commandStatsOptions = {
    tooltip: {
      trigger: 'item',
      formatter: '{a} <br/>{b} : {c} ({d}%)',
    },
    series: [
      {
        name: '命令',
        type: 'pie',
        roseType: 'radius',
        radius: [15, 95],
        center: ['50%', '38%'],
        data: cacheData.commandStats || [],
        animationEasing: 'cubicInOut',
        animationDuration: 1000,
      },
    ],
  };

  const usedMemoryOptions = {
    tooltip: {
      formatter: `{b} <br/>{a} : ${toDisplayText(cacheData.info?.used_memory_human)}`,
    },
    series: [
      {
        name: '峰值',
        type: 'gauge',
        min: 0,
        max: 1000,
        detail: {
          formatter: toDisplayText(cacheData.info?.used_memory_human),
        },
        data: [
          {
            value: Number.parseFloat(toDisplayText(cacheData.info?.used_memory_human)) || 0,
            name: '内存消耗',
          },
        ],
      },
    ],
  };

  return (
    <div className="app-container cache-monitor-container">
      <Row gutter={[16, 16]}>
        <Col span={24} className="card-box">
          <Card title="基本信息">
            <Descriptions bordered column={4}>
              <Descriptions.Item label="Redis版本">{toDisplayText(cacheData.info?.redis_version)}</Descriptions.Item>
              <Descriptions.Item label="运行模式">
                {cacheData.info?.redis_mode === 'standalone' ? '单机' : toDisplayText(cacheData.info?.redis_mode)}
              </Descriptions.Item>
              <Descriptions.Item label="端口">{toDisplayText(cacheData.info?.tcp_port)}</Descriptions.Item>
              <Descriptions.Item label="客户端数">{toDisplayText(cacheData.info?.connected_clients)}</Descriptions.Item>
              <Descriptions.Item label="运行时间(天)">{toDisplayText(cacheData.info?.uptime_in_days)}</Descriptions.Item>
              <Descriptions.Item label="使用内存">{toDisplayText(cacheData.info?.used_memory_human)}</Descriptions.Item>
              <Descriptions.Item label="使用CPU">
                {cacheData.info?.used_cpu_user_children
                  ? Number.parseFloat(toDisplayText(cacheData.info.used_cpu_user_children)).toFixed(2)
                  : ''}
              </Descriptions.Item>
              <Descriptions.Item label="内存配置">{toDisplayText(cacheData.info?.maxmemory_human)}</Descriptions.Item>
              <Descriptions.Item label="AOF是否开启">
                {cacheData.info?.aof_enabled === '0' ? '否' : (cacheData.info?.aof_enabled ? '是' : '')}
              </Descriptions.Item>
              <Descriptions.Item label="RDB是否成功">{toDisplayText(cacheData.info?.rdb_last_bgsave_status)}</Descriptions.Item>
              <Descriptions.Item label="Key数量">{cacheData.dbSize || ''}</Descriptions.Item>
              <Descriptions.Item label="网络入口/出口">
                {cacheData.info?.instantaneous_input_kbps
                  ? `${cacheData.info.instantaneous_input_kbps}kps/${cacheData.info.instantaneous_output_kbps}kps`
                  : ''}
              </Descriptions.Item>
            </Descriptions>
          </Card>
        </Col>
        <Col span={12} className="card-box">
          <Card title="命令统计">
            <ReactEChartsCore echarts={echarts} theme="macarons" option={commandStatsOptions} style={{ height: '420px' }} />
          </Card>
        </Col>
        <Col span={12} className="card-box">
          <Card title="内存信息">
            <ReactEChartsCore echarts={echarts} theme="macarons" option={usedMemoryOptions} style={{ height: '420px' }} />
          </Card>
        </Col>
      </Row>
    </div>
  );
};

export default CacheMonitorPage;