import React, { useState, useEffect } from 'react';
import { Card, Typography, Table, Statistic, Row, Col, Tag, Select, DatePicker, Space, Spin, Button, Modal, Form, Input, InputNumber, message, Divider } from 'antd';
import { DollarOutlined, RiseOutlined, FallOutlined, PlusOutlined, DownloadOutlined } from '@ant-design/icons';
import apiClient from '../../utils/request';
import dayjs from 'dayjs';
import * as XLSX from 'xlsx';

const { Title, Paragraph } = Typography;
const { RangePicker } = DatePicker;

const LEVEL1_LABELS: Record<string, string> = { income: '收入', project: '项目支出', company: '公司支出' };
const LEVEL2_LABELS: Record<string, string> = {
  contract_payment: '项目合同收款', deposit_refund: '质保金退回', shareholder_investment: '股东投资入股', other_income: '其他收入',
  material: '材料采购', equipment: '设备采购', subcontract: '施工分包', labor: '人工工资',
  travel: '差旅交通', accommodation: '食宿费用', freight: '运输物流', design: '勘测设计',
  tools: '小型工具', client_relations: '客户/EDL关系', other_project: '其他项目支出',
  salary: '工资薪酬', rent: '房租物业', office: '办公费用', commute: '交通通勤',
  vehicle_maintenance: '车辆维保', assets: '固定资产', marketing: '营销拓展',
  entertainment: '招待费用', welfare: '员工福利', logistics: '快递物流', other_company: '其他公司支出'
};

const COUNTERPARTY_TYPES = [
  { value: 'supplier', label: '供应商' }, { value: 'subcontractor', label: '分包商' },
  { value: 'customer', label: '客户' }, { value: 'employee', label: '员工' },
  { value: 'logistics', label: '物流公司' }, { value: 'shareholder', label: '股东' },
  { value: 'other', label: '其他' },
];

const CURRENCIES = [
  { value: 'CNY', label: 'CNY (人民币)' },
  { value: 'LAK', label: 'LAK (老挝基普)' },
  { value: 'USD', label: 'USD (美元)' },
  { value: 'THB', label: 'THB (泰铢)' },
];

const FinancePage: React.FC = () => {
  const [loading, setLoading] = useState(false);
  const [summary, setSummary] = useState<any>({ total_income: 0, total_expense: 0, net_profit: 0 });
  const [byCategory, setByCategory] = useState<any[]>([]);
  const [records, setRecords] = useState<any[]>([]);
  const [pagination, setPagination] = useState({ page: 1, pageSize: 20, total: 0 });
  const [dateRange, setDateRange] = useState<[dayjs.Dayjs | null, dayjs.Dayjs | null] | null>(null);
  const [filterType, setFilterType] = useState<string | undefined>(undefined);
  const [isMobile, setIsMobile] = useState(false);

  const [addModalVisible, setAddModalVisible] = useState(false);
  const [addLoading, setAddLoading] = useState(false);
  const [form] = Form.useForm();

  const [categories, setCategories] = useState<any>({ income: [], project: [], company: [] });
  const [projects, setProjects] = useState<any[]>([]);
  const [exchangeRates, setExchangeRates] = useState<Record<string, number>>({ CNY: 1, LAK: 0.0003, USD: 7.2, THB: 0.2 });

  useEffect(() => {
    const checkMobile = () => setIsMobile(window.innerWidth <= 768);
    checkMobile();
    window.addEventListener('resize', checkMobile);
    return () => window.removeEventListener('resize', checkMobile);
  }, []);

  useEffect(() => {
    apiClient.get('/expense-categories/grouped').then(res => {
      if (res.data.success) setCategories(res.data.data);
    }).catch(() => {});
    apiClient.get('/projects', { params: { pageSize: 200 } }).then(res => {
      if (res.data.success) setProjects(res.data.data || res.data.projects || []);
    }).catch(() => {});
    apiClient.get('/exchange-rates/latest').then(res => {
      if (res.data.success && res.data.data) {
        const rates: Record<string, number> = { CNY: 1 };
        const data = res.data.data;
        if (data.CNY_LAK) rates.LAK = 1 / parseFloat(data.CNY_LAK);
        if (data.CNY_USD) rates.USD = 1 / parseFloat(data.CNY_USD);
        if (data.CNY_THB) rates.THB = 1 / parseFloat(data.CNY_THB);
        setExchangeRates(rates);
      }
    }).catch(() => {});
  }, []);

  const fetchSummary = async () => {
    try {
      const params: any = {};
      if (dateRange && dateRange[0]) {
        params.date_from = dateRange[0].format('YYYY-MM-DD');
        params.date_to = dateRange[1]?.format('YYYY-MM-DD');
      }
      const res = await apiClient.get('/financial-records/summary', { params });
      if (res.data.success) {
        setSummary(res.data.data.totals);
        setByCategory(res.data.data.byCategory);
      }
    } catch (e) { console.error(e); }
  };

  const fetchRecords = async (page = 1) => {
    setLoading(true);
    try {
      const params: any = { page, pageSize: pagination.pageSize };
      if (dateRange && dateRange[0]) {
        params.date_from = dateRange[0].format('YYYY-MM-DD');
        params.date_to = dateRange[1]?.format('YYYY-MM-DD');
      }
      if (filterType) params.txn_type = filterType;
      const res = await apiClient.get('/financial-records', { params });
      if (res.data.success) {
        setRecords(res.data.data);
        setPagination(res.data.pagination);
      }
    } catch (e) { console.error(e); }
    setLoading(false);
  };

  useEffect(() => { fetchSummary(); fetchRecords(1); }, [dateRange, filterType]);

  const handleAdd = () => {
    form.resetFields();
    form.setFieldsValue({ record_date: dayjs(), currency: 'CNY', exchange_rate: 1 });
    setAddModalVisible(true);
  };

  const handleTxnTypeChange = (v: string) => {
    form.setFieldsValue({ category_level1: undefined, category_level2: undefined });
    if (v === 'income') {
      form.setFieldsValue({ category_level1: 'income' });
    }
  };

  const handleLevel1Change = () => {
    form.setFieldsValue({ category_level2: undefined });
  };

  const handleCurrencyChange = (currency: string) => {
    const rate = exchangeRates[currency] || 1;
    form.setFieldsValue({ exchange_rate: rate });
    const amount = form.getFieldValue('amount_original') || 0;
    form.setFieldsValue({ amount_cny: Math.round(amount * rate * 100) / 100 });
  };

  const handleAmountChange = (val: number | null) => {
    const rate = form.getFieldValue('exchange_rate') || 1;
    const amount = val || 0;
    form.setFieldsValue({ amount_cny: Math.round(amount * rate * 100) / 100 });
  };

  const handleRateChange = (val: number | null) => {
    const amount = form.getFieldValue('amount_original') || 0;
    const rate = val || 1;
    form.setFieldsValue({ amount_cny: Math.round(amount * rate * 100) / 100 });
  };

  const handleSave = async () => {
    try {
      const values = await form.validateFields();
      setAddLoading(true);
      const payload = {
        ...values,
        record_date: values.record_date?.format('YYYY-MM-DD'),
        amount_cny: Math.round((values.amount_original || 0) * (values.exchange_rate || 1) * 100) / 100,
        source: 'manual',
      };
      if (payload.category_level1 !== 'project' && payload.category_level1 !== 'income') {
        payload.project_id = undefined;
      }
      await apiClient.post('/financial-records', payload);
      message.success('录入成功');
      setAddModalVisible(false);
      fetchSummary();
      fetchRecords(1);
    } catch (e: any) {
      if (e.response?.data?.message) message.error(e.response.data.message);
    }
    setAddLoading(false);
  };

  const handleExport = async () => {
    try {
      message.loading({ content: '正在导出...', key: 'export' });
      const res = await apiClient.get('/financial-records', { params: { page: 1, pageSize: 5000 } });
      if (!res.data.success) return;
      const data = res.data.data;

      const wb = XLSX.utils.book_new();
      const headers = ['日期', '收支类型', '一级分类', '二级分类', '项目名称', '金额', '币种', '汇率', '等效人民币', '对方名称', '对方类型', '人员姓名', '描述', '凭证编号'];
      const rows = data.map((r: any) => [
        r.record_date,
        r.txn_type === 'income' ? '收入' : '支出',
        LEVEL1_LABELS[r.category_level1] || r.category_level1,
        LEVEL2_LABELS[r.category_level2] || r.category_level2,
        r.project_name || '',
        r.amount_original,
        r.currency,
        r.exchange_rate,
        r.amount_cny,
        r.counterparty_name || '',
        COUNTERPARTY_TYPES.find(c => c.value === r.counterparty_type)?.label || r.counterparty_type || '',
        r.user_name || '',
        r.description || '',
        r.voucher_no || '',
      ]);
      const ws = XLSX.utils.aoa_to_sheet([headers, ...rows]);
      ws['!cols'] = headers.map(() => ({ wch: 14 }));
      XLSX.utils.book_append_sheet(wb, ws, '财务记账');
      XLSX.writeFile(wb, `财务记录_${dayjs().format('YYYYMMDD')}.xlsx`);
      message.success({ content: '导出成功', key: 'export' });
    } catch (e) {
      message.error({ content: '导出失败', key: 'export' });
    }
  };

  const getLevel1Options = () => {
    const txnType = form.getFieldValue('txn_type');
    if (txnType === 'income') return [{ value: 'income', label: '收入' }];
    return [{ value: 'project', label: '项目支出' }, { value: 'company', label: '公司支出' }];
  };

  const getLevel2Options = () => {
    const level1 = form.getFieldValue('category_level1');
    if (!level1 || !categories[level1]) return [];
    return categories[level1].map((c: any) => ({ value: c.value, label: c.label }));
  };

  const projectOptions = projects.map((p: any) => ({ value: p.id, label: p.name }));

  const desktopColumns = [
    { title: '日期', dataIndex: 'record_date', width: 100, sorter: (a: any, b: any) => a.record_date?.localeCompare(b.record_date) },
    { title: '收支', dataIndex: 'txn_type', width: 60, render: (v: string) => <Tag color={v === 'income' ? 'green' : 'red'}>{v === 'income' ? '收入' : '支出'}</Tag> },
    { title: '一级分类', dataIndex: 'category_level1', width: 90, render: (v: string) => LEVEL1_LABELS[v] || v },
    { title: '二级分类', dataIndex: 'category_level2', width: 100, render: (v: string) => LEVEL2_LABELS[v] || v },
    { title: '项目', dataIndex: 'project_name', width: 140, ellipsis: true },
    { title: '原始金额', dataIndex: 'amount_original', width: 100, render: (v: number) => v?.toLocaleString(), align: 'right' as const },
    { title: '币种', dataIndex: 'currency', width: 50 },
    { title: '等效人民币', dataIndex: 'amount_cny', width: 110, render: (v: number) => `¥${v?.toLocaleString()}`, align: 'right' as const, sorter: (a: any, b: any) => a.amount_cny - b.amount_cny },
    { title: '人员', dataIndex: 'user_name', width: 70 },
    { title: '描述', dataIndex: 'description', ellipsis: true },
    { title: '来源', dataIndex: 'source', width: 80, render: (v: string) => {
      const m: Record<string, string> = { manual: '手动', advance: '预支', reimbursement: '报销', payment_request: '付款', material: '材料', primary_freight: '运费', secondary_freight: '运费' };
      return <Tag>{m[v] || v}</Tag>;
    }},
  ];

  const mobileColumns = [
    { title: '日期', dataIndex: 'record_date', width: 80 },
    { title: '收支', dataIndex: 'txn_type', width: 40, render: (v: string) => <span style={{ color: v === 'income' ? 'green' : 'red' }}>{v === 'income' ? '↑' : '↓'}</span> },
    { title: '分类', dataIndex: 'category_level2', width: 80, render: (v: string) => LEVEL2_LABELS[v] || v },
    { title: '金额', dataIndex: 'amount_cny', render: (v: number) => <b>¥{v?.toLocaleString()}</b>, align: 'right' as const },
  ];

  return (
    <div>
      <div style={{ marginBottom: 16, display: 'flex', justifyContent: 'space-between', alignItems: 'center', flexWrap: 'wrap', gap: 8 }}>
        <div>
          <Title level={3} style={{ marginBottom: 0 }}>财务管理</Title>
        </div>
        <Space>
          <Button type="primary" icon={<PlusOutlined />} onClick={handleAdd}>
            {isMobile ? '新增' : '新增记录'}
          </Button>
          <Button icon={<DownloadOutlined />} onClick={handleExport}>
            {isMobile ? '导出' : '导出Excel'}
          </Button>
        </Space>
      </div>

      <Row gutter={[8, 8]} style={{ marginBottom: 16 }}>
        <Col xs={8} sm={8}>
          <Card size="small" style={{ textAlign: 'center' }}>
            <Statistic title={<span style={{ fontSize: 12 }}>总收入</span>} value={summary.total_income} prefix="¥"
              valueStyle={{ color: '#3f8600', fontSize: isMobile ? 16 : undefined }} />
          </Card>
        </Col>
        <Col xs={8} sm={8}>
          <Card size="small" style={{ textAlign: 'center' }}>
            <Statistic title={<span style={{ fontSize: 12 }}>总支出</span>} value={summary.total_expense} prefix="¥"
              valueStyle={{ color: '#cf1322', fontSize: isMobile ? 16 : undefined }} />
          </Card>
        </Col>
        <Col xs={8} sm={8}>
          <Card size="small" style={{ textAlign: 'center' }}>
            <Statistic title={<span style={{ fontSize: 12 }}>净利润</span>} value={summary.net_profit} prefix="¥"
              valueStyle={{ color: summary.net_profit >= 0 ? '#3f8600' : '#cf1322', fontSize: isMobile ? 16 : undefined }} />
          </Card>
        </Col>
      </Row>

      {byCategory.length > 0 && (
        <Card title="支出分类汇总" size="small" style={{ marginBottom: 16 }}>
          <Row gutter={[8, 8]}>
            {byCategory.filter(c => c.category_level1 !== 'income').map((c, i) => (
              <Col xs={12} sm={8} md={6} key={i}>
                <div style={{ fontSize: 12, color: '#666' }}>{LEVEL2_LABELS[c.category_level2] || c.category_level2}</div>
                <div style={{ fontWeight: 'bold' }}>¥{parseFloat(c.total_amount).toLocaleString()}</div>
              </Col>
            ))}
          </Row>
        </Card>
      )}

      <Card title="财务明细" size="small" styles={{ body: { padding: isMobile ? 8 : 24 } }}
        extra={
          <Space size="small" wrap>
            <RangePicker size="small" onChange={(dates) => setDateRange(dates as any)} />
            <Select size="small" allowClear placeholder="筛选类型" style={{ width: 100 }}
              onChange={setFilterType} value={filterType}
              options={[{ value: 'income', label: '收入' }, { value: 'expense', label: '支出' }]} />
          </Space>
        }
      >
        <Spin spinning={loading}>
          <Table
            dataSource={records}
            columns={isMobile ? mobileColumns : desktopColumns}
            rowKey="id"
            size={isMobile ? 'small' : 'middle'}
            scroll={isMobile ? { x: 400 } : { x: 1100 }}
            pagination={{
              current: pagination.page,
              pageSize: pagination.pageSize,
              total: pagination.total,
              onChange: (page) => fetchRecords(page),
              size: isMobile ? 'small' : 'default',
              showTotal: (total) => `共 ${total} 条`
            }}
          />
        </Spin>
      </Card>

      <Modal
        title="新增财务记录"
        open={addModalVisible}
        onOk={handleSave}
        onCancel={() => setAddModalVisible(false)}
        confirmLoading={addLoading}
        okText="保存"
        cancelText="取消"
        width={isMobile ? '95%' : 600}
        style={{ top: isMobile ? 10 : 40 }}
        destroyOnClose
      >
        <Form form={form} layout={isMobile ? 'vertical' : 'horizontal'} labelCol={{ span: isMobile ? 24 : 6 }} wrapperCol={{ span: isMobile ? 24 : 18 }} size="middle">

          <Form.Item name="record_date" label="日期" rules={[{ required: true, message: '请选择日期' }]}>
            <DatePicker style={{ width: '100%' }} />
          </Form.Item>

          <Form.Item name="txn_type" label="收支类型" rules={[{ required: true, message: '请选择' }]}>
            <Select onChange={handleTxnTypeChange} options={[{ value: 'income', label: '收入' }, { value: 'expense', label: '支出' }]} placeholder="请选择" />
          </Form.Item>

          <Form.Item name="category_level1" label="一级分类" rules={[{ required: true, message: '请选择' }]}>
            <Select onChange={handleLevel1Change} options={getLevel1Options()} placeholder="请选择" />
          </Form.Item>

          <Form.Item name="category_level2" label="二级分类" rules={[{ required: true, message: '请选择' }]}>
            <Select options={getLevel2Options()} placeholder="请先选择一级分类" notFoundContent="请先选择一级分类" />
          </Form.Item>

          <Form.Item name="project_id" label="项目名称"
            rules={[{ required: form.getFieldValue('category_level1') === 'project' || (form.getFieldValue('category_level1') === 'income' && form.getFieldValue('category_level2') !== 'shareholder_investment' && form.getFieldValue('category_level2') !== 'other_income'), message: '请选择项目' }]}
          >
            <Select showSearch optionFilterProp="label" options={projectOptions} placeholder="选择项目" allowClear />
          </Form.Item>

          <Row gutter={8}>
            <Col span={10}>
              <Form.Item name="amount_original" label={isMobile ? '金额' : '金额'} labelCol={{ span: isMobile ? 24 : 8 }} wrapperCol={{ span: isMobile ? 24 : 16 }} rules={[{ required: true, message: '请输入' }]}>
                <InputNumber style={{ width: '100%' }} min={0} precision={2} onChange={handleAmountChange} placeholder="0" />
              </Form.Item>
            </Col>
            <Col span={7}>
              <Form.Item name="currency" label={isMobile ? '币种' : ''} labelCol={{ span: isMobile ? 24 : 0 }} wrapperCol={{ span: isMobile ? 24 : 24 }} rules={[{ required: true }]}>
                <Select options={CURRENCIES} onChange={handleCurrencyChange} />
              </Form.Item>
            </Col>
            <Col span={7}>
              <Form.Item name="exchange_rate" label={isMobile ? '汇率' : ''} labelCol={{ span: isMobile ? 24 : 0 }} wrapperCol={{ span: isMobile ? 24 : 24 }} rules={[{ required: true }]}>
                <InputNumber style={{ width: '100%' }} min={0} step={0.0001} precision={6} onChange={handleRateChange} />
              </Form.Item>
            </Col>
          </Row>

          <Form.Item label="等效人民币">
            <span style={{ fontSize: 18, fontWeight: 'bold', color: '#1890ff' }}>
              ¥{((form.getFieldValue('amount_original') || 0) * (form.getFieldValue('exchange_rate') || 1)).toLocaleString(undefined, { minimumFractionDigits: 2, maximumFractionDigits: 2 })}
            </span>
          </Form.Item>

          <Divider style={{ margin: '8px 0' }} />

          <Form.Item name="counterparty_name" label="对方名称" labelCol={{ span: isMobile ? 24 : 6 }} wrapperCol={{ span: isMobile ? 24 : 18 }}>
            <Input placeholder="收款方/付款方名称" />
          </Form.Item>

          <Form.Item name="counterparty_type" label="对方类型" labelCol={{ span: isMobile ? 24 : 6 }} wrapperCol={{ span: isMobile ? 24 : 18 }}>
            <Select options={COUNTERPARTY_TYPES} placeholder="选择类型" allowClear />
          </Form.Item>

          <Form.Item name="user_name" label="人员姓名" labelCol={{ span: isMobile ? 24 : 6 }} wrapperCol={{ span: isMobile ? 24 : 18 }}>
            <Input placeholder="关联员工姓名" />
          </Form.Item>

          <Form.Item name="description" label="描述" labelCol={{ span: isMobile ? 24 : 6 }} wrapperCol={{ span: isMobile ? 24 : 18 }}>
            <Input.TextArea rows={2} placeholder="补充说明" />
          </Form.Item>

          <Form.Item name="voucher_no" label="凭证编号" labelCol={{ span: isMobile ? 24 : 6 }} wrapperCol={{ span: isMobile ? 24 : 18 }}>
            <Input placeholder="发票号/收据号" />
          </Form.Item>
        </Form>
      </Modal>
    </div>
  );
};

export default FinancePage;
