import { Button, Card, Form, Select, Space, Table, Tag, Toast, Typography } from '@douyinfe/semi-ui';
import { useEffect, useState } from 'react';
import { api } from '../api/client';
import type { DailyMileageRow, MileageSummary } from '../api/types';
import { PageHeader } from '../components/PageHeader';

const emptySummary: MileageSummary = {
  vehicleCount: 0,
  recordCount: 0,
  sourceCount: 0,
  totalMileageKm: 0,
  averageMileagePerVin: 0
};

function mileageParams(values: Record<string, string>, pageSize?: number, offset?: number) {
  const params = new URLSearchParams();
  if (pageSize != null) params.set('limit', String(pageSize));
  if (offset != null) params.set('offset', String(offset));
  if (values?.keyword) params.set('keyword', values.keyword);
  if (values?.protocol) params.set('protocol', values.protocol);
  if (values?.dateFrom) params.set('dateFrom', values.dateFrom);
  if (values?.dateTo) params.set('dateTo', values.dateTo);
  return params;
}

function formatKm(value: number) {
  return Number.isFinite(value) ? value.toLocaleString(undefined, { maximumFractionDigits: 1 }) : '0';
}

function canOpenVehicle(vin?: string) {
  const value = vin?.trim();
  return Boolean(value && value !== 'unknown');
}

export function Mileage({ initialVin, initialProtocol, onOpenVehicle }: { initialVin: string; initialProtocol?: string; onOpenVehicle: (vin: string, protocol?: string) => void }) {
  const [rows, setRows] = useState<DailyMileageRow[]>([]);
  const [summary, setSummary] = useState<MileageSummary>(emptySummary);
  const [loading, setLoading] = useState(true);
  const [summaryLoading, setSummaryLoading] = useState(true);
  const [filters, setFilters] = useState<Record<string, string>>({ keyword: initialVin, protocol: initialProtocol ?? '' });
  const [pagination, setPagination] = useState({ currentPage: 1, pageSize: 20, total: 0 });
  const currentVehicleKeyword = filters.keyword?.trim() ?? '';
  const currentProtocol = filters.protocol?.trim() ?? '';

  const loadSummary = (values: Record<string, string> = filters) => {
    setSummaryLoading(true);
    api.mileageSummary(mileageParams(values))
      .then(setSummary)
      .catch((error: Error) => Toast.error(error.message))
      .finally(() => setSummaryLoading(false));
  };

  const load = (values: Record<string, string> = filters, page = pagination.currentPage, pageSize = pagination.pageSize) => {
    setLoading(true);
    api.dailyMileage(mileageParams(values, pageSize, (page - 1) * pageSize))
      .then((nextPage) => {
        setRows(nextPage.items);
        setPagination({ currentPage: page, pageSize, total: nextPage.total });
      })
      .catch((error: Error) => Toast.error(error.message))
      .finally(() => setLoading(false));
  };

  useEffect(() => {
    const nextFilters = { keyword: initialVin, protocol: initialProtocol ?? '' };
    setFilters(nextFilters);
    loadSummary(nextFilters);
    load(nextFilters, 1, pagination.pageSize);
  }, [initialVin, initialProtocol]);

  return (
    <div className="vp-page">
      <PageHeader
        title="里程统计"
        description="按车辆汇总每日里程、区间里程和异常差值分析"
        actions={(
          <Button disabled={!currentVehicleKeyword} onClick={() => onOpenVehicle(currentVehicleKeyword)}>
            当前车辆服务
          </Button>
        )}
      />
      <div className="vp-scope-bar">
        <span className="vp-scope-label">当前车辆：{currentVehicleKeyword || '-'}</span>
        <Tag color={currentProtocol ? 'blue' : 'green'}>当前来源：{currentProtocol || '全部来源'}</Tag>
        <Typography.Text type="tertiary">里程统计按当前车辆与来源范围汇总。</Typography.Text>
      </div>
      <Card bordered>
        <Form key={filters.keyword ?? ''} initValues={filters} layout="horizontal" onSubmit={(values) => {
          const nextFilters = values as Record<string, string>;
          setFilters(nextFilters);
          loadSummary(nextFilters);
          load(nextFilters, 1, pagination.pageSize);
        }}>
          <Form.Input field="keyword" label="车辆关键词" placeholder="VIN / 车牌 / 手机号 / OEM" style={{ width: 260 }} />
          <Form.Select field="protocol" label="数据来源" placeholder="全部来源" style={{ width: 180 }}>
            <Select.Option value="GB32960">GB32960</Select.Option>
            <Select.Option value="JT808">JT808</Select.Option>
            <Select.Option value="YUTONG_MQTT">YUTONG_MQTT</Select.Option>
          </Form.Select>
          <Form.Input field="dateFrom" label="开始日期" placeholder="2026-07-01" style={{ width: 160 }} />
          <Form.Input field="dateTo" label="结束日期" placeholder="2026-07-03" style={{ width: 160 }} />
          <Space>
            <Button htmlType="submit" theme="solid" type="primary">查询</Button>
            <Button onClick={() => {
              const nextFilters = { keyword: initialVin, protocol: initialProtocol ?? '' };
              setFilters(nextFilters);
              loadSummary(nextFilters);
              load(nextFilters, 1, pagination.pageSize);
            }}>重置</Button>
          </Space>
        </Form>
      </Card>
      <div className="vp-kpi-grid" style={{ marginTop: 16 }}>
        {[
          { label: '车辆数', value: summary.vehicleCount.toLocaleString() },
          { label: '累计里程 km', value: formatKm(summary.totalMileageKm) },
          { label: '单车平均 km', value: formatKm(summary.averageMileagePerVin) },
          { label: '来源 / 记录', value: `${summary.sourceCount}/${summary.recordCount.toLocaleString()}` }
        ].map((item) => (
          <Card key={item.label} bordered loading={summaryLoading}>
            <div className="vp-kpi-value">{item.value}</div>
            <div className="vp-kpi-label">{item.label}</div>
          </Card>
        ))}
      </div>
      <Card bordered style={{ marginTop: 16 }}>
        <Table
          loading={loading}
          rowKey={(row?: DailyMileageRow) => `${row?.date ?? ''}-${row?.vin ?? ''}-${row?.source ?? ''}`}
          dataSource={rows}
          pagination={{
            currentPage: pagination.currentPage,
            pageSize: pagination.pageSize,
            total: pagination.total,
            showSizeChanger: true,
            onPageChange: (page) => load(filters, page, pagination.pageSize),
            onPageSizeChange: (pageSize) => load(filters, 1, pageSize)
          }}
          columns={[
            { title: '日期', dataIndex: 'date' },
            { title: 'VIN', dataIndex: 'vin' },
            { title: '车牌', dataIndex: 'plate' },
            { title: '起始里程', dataIndex: 'startMileageKm' },
            { title: '结束里程', dataIndex: 'endMileageKm' },
            { title: '日里程', dataIndex: 'dailyMileageKm' },
            { title: '来源', dataIndex: 'source' },
            { title: '异常', render: (_: unknown, row: DailyMileageRow) => row.anomalySeverity ? <Tag color="orange">{row.anomalySeverity}</Tag> : <Tag color="green">正常</Tag> },
            {
              title: '操作',
              width: 110,
              render: (_: unknown, row: DailyMileageRow) => (
                <Button disabled={!canOpenVehicle(row.vin)} onClick={() => onOpenVehicle(row.vin)}>车辆服务</Button>
              )
            }
          ]}
        />
      </Card>
    </div>
  );
}