import React, { useCallback, useEffect, useState } from 'react';
import { useParams } from 'react-router-dom';
import { useQuery, useMutation, useQueryClient } from '@tanstack/react-query';
import {
  Card,
  Button,
  Space,
  Typography,
  Row,
  Col,
  Statistic,
  Table,
  Tag,
  Divider,
  Descriptions,
  Checkbox,
  message,
  Result,
} from 'antd';
import {
  FileTextOutlined,
  FileExcelOutlined,
  FilePdfOutlined,
  FileWordOutlined,
  DownloadOutlined,
  PrinterOutlined,
  HistoryOutlined,
  CheckCircleOutlined,
} from '@ant-design/icons';
import type { ColumnsType } from 'antd/es/table';
import { fetchCase, fetchAssessments, fetchReports, generateReport, getReportDownloadUrl } from '../../services/api';

type ContentKeys =
  | 'include_summary'
  | 'include_transactions'
  | 'include_flow_chart'
  | 'include_timeline'
  | 'include_reasons'
  | 'include_inquiry'
  | 'include_screenshots';

const contentOptions: Array<{ key: ContentKeys; label: string; defaultOn: boolean }> = [
  { key: 'include_summary', label: '被骗金额汇总表', defaultOn: true },
  { key: 'include_transactions', label: '交易明细清单（含证据索引）', defaultOn: true },
  { key: 'include_flow_chart', label: '资金流转路径图', defaultOn: true },
  { key: 'include_timeline', label: '交易时间轴', defaultOn: true },
  { key: 'include_reasons', label: '认定理由与排除说明', defaultOn: true },
  { key: 'include_inquiry', label: '笔录辅助问询建议', defaultOn: false },
  { key: 'include_screenshots', label: '原始截图附件', defaultOn: false },
];

const STORAGE_PREFIX = 'report-content-';

const loadContentSelection = (caseId: string): Record<ContentKeys, boolean> => {
  try {
    const raw = localStorage.getItem(`${STORAGE_PREFIX}${caseId}`);
    if (raw) return JSON.parse(raw);
  } catch { /* ignore */ }
  const defaults: Record<string, boolean> = {};
  contentOptions.forEach((o) => { defaults[o.key] = o.defaultOn; });
  return defaults as Record<ContentKeys, boolean>;
};

const saveContentSelection = (caseId: string, sel: Record<ContentKeys, boolean>) => {
  try {
    localStorage.setItem(`${STORAGE_PREFIX}${caseId}`, JSON.stringify(sel));
  } catch { /* ignore */ }
};

const Reports: React.FC = () => {
  const { id = '1' } = useParams();
  const qc = useQueryClient();
  const [generated, setGenerated] = useState(false);
  const [selectedFormats, setSelectedFormats] = useState<Array<'excel' | 'pdf' | 'word'>>([
    'excel',
    'pdf',
  ]);
  const [contentSel, setContentSel] = useState<Record<ContentKeys, boolean>>(() => loadContentSelection(id));

  useEffect(() => {
    setContentSel(loadContentSelection(id));
  }, [id]);

  const toggleContent = useCallback((key: ContentKeys, checked: boolean) => {
    setContentSel((prev) => {
      const next = { ...prev, [key]: checked };
      saveContentSelection(id, next);
      return next;
    });
  }, [id]);

  const { data: currentCase } = useQuery({ queryKey: ['case', id], queryFn: () => fetchCase(id) });
  const { data: assessData } = useQuery({ queryKey: ['assessments', id], queryFn: () => fetchAssessments(id) });
  const { data: reportsData } = useQuery({ queryKey: ['reports', id], queryFn: () => fetchReports(id) });

  const allAssessments = assessData?.items ?? [];
  const reportsList = reportsData?.items ?? [];

  const confirmedAssessments = allAssessments.filter(
    (a) => a.reviewStatus === 'confirmed' && a.assessedAmount > 0,
  );
  const totalConfirmed = confirmedAssessments.reduce(
    (s, a) => s + a.assessedAmount,
    0,
  );

  const genMutation = useMutation({
    mutationFn: async (reportTypes: Array<'excel' | 'pdf' | 'word'>) => {
      const result = await Promise.all(
        reportTypes.map((reportType) =>
          generateReport(id, { report_type: reportType, ...contentSel }),
        ),
      );
      return result;
    },
    onSuccess: (_res, vars) => {
      setGenerated(true);
      qc.invalidateQueries({ queryKey: ['reports', id] });
      message.success(`报告生成成功：${vars.map((v) => v.toUpperCase()).join(' / ')}`);
    },
    onError: () => {
      message.error('报告生成失败');
    },
  });

  if (!currentCase) return null;

  const latestReportByType = reportsList.reduce<Record<string, (typeof reportsList)[0]>>((acc, report) => {
    if (!acc[report.reportType]) {
      acc[report.reportType] = report;
    }
    return acc;
  }, {});

  const historyColumns: ColumnsType<(typeof reportsList)[0]> = [
    {
      title: '类型',
      dataIndex: 'reportType',
      width: 100,
      render: (t: string) => {
        const map: Record<string, { icon: React.ReactNode; label: string; color: string }> = {
          pdf: { icon: <FilePdfOutlined />, label: 'PDF', color: 'red' },
          excel: { icon: <FileExcelOutlined />, label: 'Excel', color: 'green' },
          word: { icon: <FileWordOutlined />, label: 'Word', color: 'blue' },
        };
        const cfg = map[t] || map.pdf;
        return <Tag icon={cfg.icon} color={cfg.color}>{cfg.label}</Tag>;
      },
    },
    {
      title: '版本',
      dataIndex: 'version',
      width: 80,
      render: (v: number) => `v${v}`,
    },
    {
      title: '生成时间',
      dataIndex: 'createdAt',
      width: 180,
    },
    {
      title: '操作',
      width: 120,
      render: (_, report) => (
        <Space>
          <Button
            type="link"
            size="small"
            icon={<DownloadOutlined />}
            href={getReportDownloadUrl(report.id)}
            target="_blank"
          >
            下载
          </Button>
        </Space>
      ),
    },
  ];

  return (
    <div>
      <Row gutter={16} style={{ marginBottom: 24 }}>
        <Col span={8}>
          <Card variant="borderless">
            <Statistic
              title="已确认被骗金额"
              value={totalConfirmed}
              precision={2}
              prefix="¥"
              valueStyle={{ color: '#cf1322', fontSize: 24 }}
            />
          </Card>
        </Col>
        <Col span={8}>
          <Card variant="borderless">
            <Statistic
              title="已确认交易笔数"
              value={confirmedAssessments.length}
              suffix="笔"
              prefix={<CheckCircleOutlined />}
              valueStyle={{ color: '#52c41a' }}
            />
          </Card>
        </Col>
        <Col span={8}>
          <Card variant="borderless">
            <Statistic
              title="历史报告"
              value={reportsList.length}
              suffix="份"
              prefix={<HistoryOutlined />}
            />
          </Card>
        </Col>
      </Row>

      <Row gutter={24}>
        <Col span={14}>
          <Card
            title={
              <Space>
                <FileTextOutlined />
                <span>生成报告</span>
              </Space>
            }
            style={{ marginBottom: 24 }}
          >
            <Descriptions column={2} size="small" style={{ marginBottom: 24 }}>
              <Descriptions.Item label="案件编号">
                {currentCase.caseNo}
              </Descriptions.Item>
              <Descriptions.Item label="案件名称">
                {currentCase.title}
              </Descriptions.Item>
              <Descriptions.Item label="受害人">
                {currentCase.victimName}
              </Descriptions.Item>
              <Descriptions.Item label="承办人">
                {currentCase.handler}
              </Descriptions.Item>
              <Descriptions.Item label="已确认金额">
                <Typography.Text strong style={{ color: '#cf1322' }}>
                  ¥{totalConfirmed.toLocaleString('zh-CN', { minimumFractionDigits: 2 })}
                </Typography.Text>
              </Descriptions.Item>
              <Descriptions.Item label="确认笔数">
                {confirmedAssessments.length} 笔
              </Descriptions.Item>
            </Descriptions>

            <Divider />

            <Typography.Text strong>导出格式：</Typography.Text>
            <div style={{ margin: '12px 0 24px' }}>
              <Space size={16}>
                <Card
                  hoverable
                  style={{ width: 140, textAlign: 'center' }}
                  styles={{ body: { padding: 16 } }}
                >
                  <FileExcelOutlined style={{ fontSize: 32, color: '#52c41a' }} />
                  <div style={{ marginTop: 8 }}>
                    <Typography.Text>Excel 汇总表</Typography.Text>
                  </div>
                  <div>
                    <Checkbox
                      checked={selectedFormats.includes('excel')}
                      onChange={(e) => {
                        setSelectedFormats((prev) =>
                          e.target.checked
                            ? Array.from(new Set([...prev, 'excel']))
                            : prev.filter((x) => x !== 'excel'),
                        );
                      }}
                    >
                      选择
                    </Checkbox>
                  </div>
                </Card>
                <Card
                  hoverable
                  style={{ width: 140, textAlign: 'center' }}
                  styles={{ body: { padding: 16 } }}
                >
                  <FilePdfOutlined style={{ fontSize: 32, color: '#cf1322' }} />
                  <div style={{ marginTop: 8 }}>
                    <Typography.Text>PDF 报告</Typography.Text>
                  </div>
                  <div>
                    <Checkbox
                      checked={selectedFormats.includes('pdf')}
                      onChange={(e) => {
                        setSelectedFormats((prev) =>
                          e.target.checked
                            ? Array.from(new Set([...prev, 'pdf']))
                            : prev.filter((x) => x !== 'pdf'),
                        );
                      }}
                    >
                      选择
                    </Checkbox>
                  </div>
                </Card>
                <Card
                  hoverable
                  style={{ width: 140, textAlign: 'center' }}
                  styles={{ body: { padding: 16 } }}
                >
                  <FileWordOutlined style={{ fontSize: 32, color: '#1677ff' }} />
                  <div style={{ marginTop: 8 }}>
                    <Typography.Text>Word 文书</Typography.Text>
                  </div>
                  <div>
                    <Checkbox
                      checked={selectedFormats.includes('word')}
                      onChange={(e) => {
                        setSelectedFormats((prev) =>
                          e.target.checked
                            ? Array.from(new Set([...prev, 'word']))
                            : prev.filter((x) => x !== 'word'),
                        );
                      }}
                    >
                      选择
                    </Checkbox>
                  </div>
                </Card>
              </Space>
            </div>

            <Typography.Text strong>报告内容：</Typography.Text>
            <div style={{ margin: '12px 0 24px' }}>
              <Space direction="vertical">
                {contentOptions.map((opt) => (
                  <Checkbox
                    key={opt.key}
                    checked={contentSel[opt.key]}
                    onChange={(e) => toggleContent(opt.key, e.target.checked)}
                  >
                    {opt.label}
                  </Checkbox>
                ))}
              </Space>
            </div>

            {!generated ? (
              <Button
                type="primary"
                size="large"
                icon={<FileTextOutlined />}
                loading={genMutation.isPending}
                onClick={() => {
                  if (selectedFormats.length === 0) {
                    message.warning('请至少选择一种导出格式');
                    return;
                  }
                  genMutation.mutate(selectedFormats);
                }}
                block
              >
                {genMutation.isPending ? '正在生成报告...' : '生成报告'}
              </Button>
            ) : (
              <Result
                status="success"
                title="报告已生成"
                subTitle="您可以下载或打印以下报告文件"
                extra={[
                  <Button
                    key="excel"
                    icon={<DownloadOutlined />}
                    href={latestReportByType.excel ? getReportDownloadUrl(latestReportByType.excel.id) : undefined}
                    target="_blank"
                    disabled={!latestReportByType.excel}
                  >
                    下载 Excel
                  </Button>,
                  <Button
                    key="pdf"
                    type="primary"
                    icon={<DownloadOutlined />}
                    href={latestReportByType.pdf ? getReportDownloadUrl(latestReportByType.pdf.id) : undefined}
                    target="_blank"
                    disabled={!latestReportByType.pdf}
                  >
                    下载 PDF
                  </Button>,
                  <Button
                    key="word"
                    icon={<DownloadOutlined />}
                    href={latestReportByType.word ? getReportDownloadUrl(latestReportByType.word.id) : undefined}
                    target="_blank"
                    disabled={!latestReportByType.word}
                  >
                    下载 Word
                  </Button>,
                  <Button
                    key="print"
                    icon={<PrinterOutlined />}
                    onClick={() => message.info('演示模式：打印')}
                  >
                    打印
                  </Button>,
                ]}
              />
            )}
          </Card>
        </Col>

        <Col span={10}>
          <Card
            title={
              <Space>
                <HistoryOutlined />
                <span>历史报告</span>
              </Space>
            }
            style={{ marginBottom: 24 }}
          >
            <Table
              rowKey="id"
              columns={historyColumns}
              dataSource={reportsList}
              pagination={false}
              size="small"
            />
          </Card>

          <Card title="报告预览" style={{ minHeight: 300 }}>
            <div
              style={{
                background: '#fafafa',
                border: '1px dashed #d9d9d9',
                borderRadius: 8,
                padding: 24,
                textAlign: 'center',
                minHeight: 240,
                display: 'flex',
                flexDirection: 'column',
                alignItems: 'center',
                justifyContent: 'center',
              }}
            >
              <FileTextOutlined style={{ fontSize: 48, color: '#bfbfbf' }} />
              <Typography.Text type="secondary" style={{ marginTop: 12 }}>
                {generated
                  ? '点击左侧"下载"查看完整报告'
                  : '生成报告后可在此预览'}
              </Typography.Text>
            </div>
          </Card>
        </Col>
      </Row>
    </div>
  );
};

export default Reports;