import React, { useEffect, useMemo, useRef, useState } from 'react';
import { useNavigate, useParams } from 'react-router-dom';
import { useMutation, useQuery, useQueryClient } from '@tanstack/react-query';
import {
  App,
  Card,
  Steps,
  Row,
  Col,
  Statistic,
  Typography,
  Upload,
  Button,
  Space,
  Tag,
  Descriptions,
  Progress,
  Alert,
  Empty,
} from 'antd';
import {
  CloudUploadOutlined,
  ScanOutlined,
  MergeCellsOutlined,
  ApartmentOutlined,
  AuditOutlined,
  FileTextOutlined,
  InboxOutlined,
  RightOutlined,
  PlayCircleOutlined,
  ThunderboltOutlined,
} from '@ant-design/icons';
import { fetchCase, fetchImages, fetchTransactions, fetchAssessments, uploadImages, startCaseOcr, triggerAnalysis } from '../../services/api';
import type { EvidenceImage } from '../../types';

const { Dragger } = Upload;

type UploadBatchItem = {
  localId: string;
  fileName: string;
  fileSize: number;
  status: 'uploading' | 'success' | 'error';
  uploadedImageId?: string;
  previewUrl?: string;
};

const formatFileSize = (size: number): string => {
  if (!Number.isFinite(size) || size <= 0) return '-';
  if (size < 1024) return `${size} B`;
  if (size < 1024 * 1024) return `${(size / 1024).toFixed(1)} KB`;
  return `${(size / (1024 * 1024)).toFixed(1)} MB`;
};

const Workspace: React.FC = () => {
  const { id = '1' } = useParams();
  const navigate = useNavigate();
  const queryClient = useQueryClient();
  const { message } = App.useApp();
  const [uploadingCount, setUploadingCount] = useState(0);
  const [uploadBatchItems, setUploadBatchItems] = useState<UploadBatchItem[]>([]);
  const batchCounterRef = useRef<{ success: number; failed: number }>({ success: 0, failed: 0 });
  const batchActiveRef = useRef(false);

  useEffect(() => {
    return () => {
      uploadBatchItems.forEach((item) => {
        if (item.previewUrl) URL.revokeObjectURL(item.previewUrl);
      });
    };
  }, [uploadBatchItems]);

  const { data: currentCase } = useQuery({ queryKey: ['case', id], queryFn: () => fetchCase(id) });
  const { data: imagesData } = useQuery({ queryKey: ['images', id], queryFn: () => fetchImages(id) });
  const { data: txData } = useQuery({ queryKey: ['transactions', id], queryFn: () => fetchTransactions(id) });
  const { data: assessData } = useQuery({ queryKey: ['assessments', id], queryFn: () => fetchAssessments(id) });
  const ocrMutation = useMutation({
    mutationFn: () => startCaseOcr(id, false),
    onMutate: () => {
      message.open({
        key: 'workspace-ocr',
        type: 'loading',
        content: '正在提交 OCR 任务...',
        duration: 0,
      });
    },
    onSuccess: (res) => {
      message.open({
        key: 'workspace-ocr',
        type: 'success',
        content: res.message,
      });
      queryClient.invalidateQueries({ queryKey: ['images', id] });
    },
    onError: () => {
      message.open({
        key: 'workspace-ocr',
        type: 'error',
        content: 'OCR任务提交失败',
      });
    },
  });
  const analysisMutation = useMutation({
    mutationFn: () => triggerAnalysis(id),
    onMutate: () => {
      message.open({
        key: 'workspace-analysis',
        type: 'loading',
        content: '正在提交案件分析任务...',
        duration: 0,
      });
    },
    onSuccess: (res) => {
      message.open({
        key: 'workspace-analysis',
        type: 'success',
        content: res.message || '分析任务已提交',
      });
      queryClient.invalidateQueries({ queryKey: ['assessments', id] });
      queryClient.invalidateQueries({ queryKey: ['suggestions', id] });
      queryClient.invalidateQueries({ queryKey: ['transactions', id] });
      queryClient.invalidateQueries({ queryKey: ['flows', id] });
      queryClient.invalidateQueries({ queryKey: ['case', id] });
    },
    onError: () => {
      message.open({
        key: 'workspace-analysis',
        type: 'error',
        content: '案件分析提交失败',
      });
    },
  });

  const images = imagesData ?? [];
  const txList = txData?.items ?? [];
  const assessments = assessData?.items ?? [];

  const highConfirm = assessments.filter((a) => a.confidenceLevel === 'high').length;
  const pendingReview = assessments.filter((a) => a.reviewStatus === 'pending').length;

  const currentStep = useMemo(() => {
    if (images.length === 0) return 0;
    const doneCount = images.filter((i: EvidenceImage) => i.ocrStatus === 'done').length;
    if (doneCount < images.length) return 1;
    if (txList.length === 0) return 2;
    if (assessments.length === 0) return 3;
    if (pendingReview > 0) return 4;
    return 5;
  }, [images, txList.length, assessments.length, pendingReview]);

  if (!currentCase) return null;

  const steps = [
    {
      title: '上传截图',
      icon: <CloudUploadOutlined />,
      description: `${images.length} 张已上传`,
    },
    {
      title: 'OCR识别',
      icon: <ScanOutlined />,
      description: `${images.filter((i: EvidenceImage) => i.ocrStatus === 'done').length}/${images.length} 已完成`,
    },
    {
      title: '交易归并',
      icon: <MergeCellsOutlined />,
      description: `${txList.length} 笔交易`,
    },
    {
      title: '资金分析',
      icon: <ApartmentOutlined />,
      description: assessments.length > 0 ? `已完成，${assessments.length} 笔认定` : '待分析',
    },
    {
      title: '认定复核',
      icon: <AuditOutlined />,
      description: `${pendingReview} 笔待复核`,
    },
    {
      title: '报告导出',
      icon: <FileTextOutlined />,
      description: '待生成',
    },
  ];

  return (
    <div>
      <Card style={{ marginBottom: 24 }}>
        <Row justify="space-between" align="middle">
          <Col>
            <Space direction="vertical" size={4}>
              <Space>
                <Typography.Title level={4} style={{ margin: 0 }}>
                  {currentCase.title}
                </Typography.Title>
                <Tag color="orange">待复核</Tag>
              </Space>
              <Typography.Text type="secondary">
                {currentCase.caseNo} · 承办人：{currentCase.handler} · 受害人：{currentCase.victimName}
              </Typography.Text>
            </Space>
          </Col>
          <Col>
            <Statistic
              title="当前识别被骗金额"
              value={currentCase.totalAmount}
              precision={2}
              prefix="¥"
              valueStyle={{ color: '#cf1322', fontSize: 28 }}
            />
          </Col>
        </Row>
      </Card>

      <Card style={{ marginBottom: 24 }}>
        <Steps
          current={currentStep}
          items={steps}
        />
      </Card>

      <Row gutter={24}>
        <Col span={16}>
          <Card
            title="快速上传截图"
            style={{ marginBottom: 24 }}
            extra={
              <Typography.Text type="secondary">
                支持 JPG/PNG，可批量拖拽
              </Typography.Text>
            }
          >
            <Dragger
              multiple
              accept="image/*"
              showUploadList={false}
              beforeUpload={(file) => {
                if (!batchActiveRef.current) {
                  batchActiveRef.current = true;
                  batchCounterRef.current = { success: 0, failed: 0 };
                  setUploadBatchItems((prev) => {
                    prev.forEach((item) => {
                      if (item.previewUrl) URL.revokeObjectURL(item.previewUrl);
                    });
                    return [];
                  });
                }

                const localId = `${Date.now()}-${Math.random().toString(36).slice(2, 8)}`;
                const previewUrl = URL.createObjectURL(file as File);
                setUploadingCount((c) => {
                  const next = c + 1;
                  message.open({
                    key: 'img-upload',
                    type: 'loading',
                    content: `正在上传截图（队列中 ${next} 张）：${file.name}`,
                    duration: 0,
                  });
                  return next;
                });
                setUploadBatchItems((prev) => [
                  ...prev,
                  {
                    localId,
                    fileName: file.name,
                    fileSize: file.size,
                    status: 'uploading',
                    previewUrl,
                  },
                ]);
                uploadImages(id, [file as File])
                  .then((uploaded) => {
                    const uploadedImage = uploaded?.[0];
                    setUploadBatchItems((prev) =>
                      prev.map((item) =>
                        item.localId === localId
                          ? {
                              ...item,
                              status: 'success',
                              uploadedImageId: uploadedImage?.id,
                            }
                          : item,
                      ),
                    );
                    batchCounterRef.current.success += 1;
                  })
                  .then(() => {
                    queryClient.invalidateQueries({ queryKey: ['images', id] });
                    queryClient.invalidateQueries({ queryKey: ['case', id] });
                  })
                  .catch(() => {
                    setUploadBatchItems((prev) =>
                      prev.map((item) =>
                        item.localId === localId
                          ? { ...item, status: 'error' }
                          : item,
                      ),
                    );
                    batchCounterRef.current.failed += 1;
                  })
                  .finally(() => {
                    setUploadingCount((c) => {
                      const next = Math.max(0, c - 1);
                      if (next === 0) {
                        batchActiveRef.current = false;
                        message.destroy('img-upload');
                        const summary = {
                          success: batchCounterRef.current.success,
                          failed: batchCounterRef.current.failed,
                        };
                        message.success(`本次上传完成：成功 ${summary.success} 张，失败 ${summary.failed} 张`);
                      } else {
                        message.open({
                          key: 'img-upload',
                          type: 'loading',
                          content: `正在上传截图（队列中 ${next} 张）...`,
                          duration: 0,
                        });
                      }
                      return next;
                    });
                  });
                return false;
              }}
              style={{ padding: '20px 0' }}
            >
              <p className="ant-upload-drag-icon">
                <InboxOutlined style={{ fontSize: 48, color: '#1677ff' }} />
              </p>
              <p className="ant-upload-text">
                点击或拖拽手机账单截图到此区域
              </p>
              <p className="ant-upload-hint">
                支持微信、支付宝、银行APP、数字钱包等多种来源截图
              </p>
            </Dragger>
            {uploadingCount > 0 && (
              <Typography.Text type="secondary">
                当前有 {uploadingCount} 张截图正在上传，请稍候...
              </Typography.Text>
            )}
            <Card
              size="small"
              title="本次上传清单"
              style={{ marginTop: 12 }}
              extra={
                uploadBatchItems.length > 0 ? (
                  <Button
                    size="small"
                    type="link"
                    onClick={() => navigate(`/cases/${id}/screenshots`)}
                  >
                    查看本次上传截图
                  </Button>
                ) : null
              }
            >
              {uploadBatchItems.length === 0 ? (
                <Empty description="暂无上传记录，请先拖拽截图上传" image={Empty.PRESENTED_IMAGE_SIMPLE} />
              ) : (
                <>
                  <Typography.Text type="secondary">
                    本次上传：共 {uploadBatchItems.length} 张，
                    成功 {uploadBatchItems.filter((x) => x.status === 'success').length} 张，
                    失败 {uploadBatchItems.filter((x) => x.status === 'error').length} 张，
                    上传中 {uploadBatchItems.filter((x) => x.status === 'uploading').length} 张
                  </Typography.Text>
                  <Space direction="vertical" style={{ width: '100%', marginTop: 10 }} size={8}>
                    {uploadBatchItems.map((item, index) => (
                      <Row key={item.localId} justify="space-between" align="middle">
                        <Col span={18}>
                          <Space size={8}>
                            <Typography.Text type="secondary">#{index + 1}</Typography.Text>
                            <div
                              style={{
                                width: 40,
                                height: 40,
                                borderRadius: 4,
                                overflow: 'hidden',
                                border: '1px solid #f0f0f0',
                                background: '#fafafa',
                              }}
                            >
                              {item.previewUrl ? (
                                <img
                                  src={item.previewUrl}
                                  alt={item.fileName}
                                  style={{ width: '100%', height: '100%', objectFit: 'cover' }}
                                />
                              ) : null}
                            </div>
                            <Typography.Text ellipsis style={{ maxWidth: 260 }}>
                              {item.fileName}
                            </Typography.Text>
                            <Typography.Text type="secondary">
                              {formatFileSize(item.fileSize)}
                            </Typography.Text>
                          </Space>
                        </Col>
                        <Col>
                          {item.status === 'uploading' && <Tag color="processing">上传中</Tag>}
                          {item.status === 'success' && <Tag color="success">上传成功</Tag>}
                          {item.status === 'error' && <Tag color="error">上传失败</Tag>}
                        </Col>
                      </Row>
                    ))}
                  </Space>
                </>
              )}
            </Card>
          </Card>

          <Card title="处理进度">
            <Row gutter={[24, 16]}>
              <Col span={8}>
                <div style={{ textAlign: 'center' }}>
                  <Progress
                    type="circle"
                    percent={Math.round(
                      images.length ? (images.filter((i: EvidenceImage) => i.ocrStatus === 'done').length /
                        images.length) *
                        100 : 0,
                    )}
                    size={80}
                  />
                  <div style={{ marginTop: 8 }}>
                    <Typography.Text>OCR 识别率</Typography.Text>
                  </div>
                </div>
              </Col>
              <Col span={8}>
                <div style={{ textAlign: 'center' }}>
                  <Progress
                    type="circle"
                    percent={Math.round(
                      txList.length ? (txList.filter((t) => !t.isDuplicate).length /
                        txList.length) *
                        100 : 0,
                    )}
                    size={80}
                    strokeColor="#52c41a"
                  />
                  <div style={{ marginTop: 8 }}>
                    <Typography.Text>去重有效率</Typography.Text>
                  </div>
                </div>
              </Col>
              <Col span={8}>
                <div style={{ textAlign: 'center' }}>
                  <Progress
                    type="circle"
                    percent={Math.round(
                      assessments.length ? (highConfirm / assessments.length) * 100 : 0,
                    )}
                    size={80}
                    strokeColor="#fa8c16"
                  />
                  <div style={{ marginTop: 8 }}>
                    <Typography.Text>高置信占比</Typography.Text>
                  </div>
                </div>
              </Col>
            </Row>
          </Card>
        </Col>

        <Col span={8}>
          <Card title="案件概况" style={{ marginBottom: 24 }}>
            <Descriptions column={1} size="small">
              <Descriptions.Item label="截图总数">
                {images.length} 张
              </Descriptions.Item>
              <Descriptions.Item label="涉及APP">
                <Space>
                  <Tag color="green">微信</Tag>
                  <Tag color="blue">支付宝</Tag>
                  <Tag color="purple">银行</Tag>
                  <Tag>数字钱包</Tag>
                </Space>
              </Descriptions.Item>
              <Descriptions.Item label="提取交易数">
                {txList.length} 笔
              </Descriptions.Item>
              <Descriptions.Item label="去重后交易">
                {txList.filter((t) => !t.isDuplicate).length} 笔
              </Descriptions.Item>
              <Descriptions.Item label="涉诈对手方">2 个</Descriptions.Item>
              <Descriptions.Item label="待复核">
                <Typography.Text type="warning">
                  {pendingReview} 笔
                </Typography.Text>
              </Descriptions.Item>
            </Descriptions>
          </Card>

          <Card title="快捷操作">
            <Space direction="vertical" style={{ width: '100%' }}>
              <Button
                block
                type="primary"
                ghost
                loading={ocrMutation.isPending}
                onClick={() => ocrMutation.mutate()}
                icon={<PlayCircleOutlined />}
              >
                开始 OCR 识别
              </Button>
              <Button
                block
                type="primary"
                ghost
                loading={analysisMutation.isPending}
                onClick={() => analysisMutation.mutate()}
                icon={<ThunderboltOutlined />}
              >
                {analysisMutation.isPending ? '分析中...' : '执行案件分析'}
              </Button>
              <Button
                block
                type="primary"
                onClick={() => navigate(`/cases/${id}/review`)}
                icon={<RightOutlined />}
              >
                进入认定复核
              </Button>
            </Space>
          </Card>

          {pendingReview > 0 && (
            <Alert
              message={`有 ${pendingReview} 笔交易待人工确认`}
              description="系统已完成自动分析，请进入认定复核页面审阅并确认结果。"
              type="warning"
              showIcon
              style={{ marginTop: 24 }}
              action={
                <Button
                  size="small"
                  type="primary"
                  onClick={() => navigate(`/cases/${id}/review`)}
                >
                  立即复核
                </Button>
              }
            />
          )}
        </Col>
      </Row>
    </div>
  );
};

export default Workspace;