import React, { useState, useEffect, useRef, useCallback, useMemo } from 'react';
import { Table, Button, Modal, Form, Input, Select, InputNumber, message, Card, Space, Popconfirm, Upload, Table as AntTable, Progress } from 'antd';
import { PlusOutlined, EditOutlined, DeleteOutlined, SearchOutlined, ExportOutlined, ImportOutlined, UploadOutlined, FileExcelOutlined, InboxOutlined } from '@ant-design/icons';
import axios from 'axios';

const { Option } = Select;

function ConsumableManagement() {
  const [consumables, setConsumables] = useState([]);
  const [loading, setLoading] = useState(true);
  const [modalVisible, setModalVisible] = useState(false);
  const [editingConsumable, setEditingConsumable] = useState(null);
  const [form] = Form.useForm();
  const [categories, setCategories] = useState([]);
  const [pagination, setPagination] = useState({
    current: 1,
    pageSize: 10,
    total: 0,
    showTotal: (total) => `共 ${total} 条记录`
  });
  const [keyword, setKeyword] = useState('');
  const [category, setCategory] = useState('all');
  const [status, setStatus] = useState('all');
  const [importModalVisible, setImportModalVisible] = useState(false);
  const [importPreview, setImportPreview] = useState([]);
  const [importFile, setImportFile] = useState(null);
  const [importing, setImporting] = useState(false);
  const [importProgress, setImportProgress] = useState(0);
  const [importPhase, setImportPhase] = useState('');
  const [importResult, setImportResult] = useState(null);
  const [stockModalVisible, setStockModalVisible] = useState(false);
  const [stockRecord, setStockRecord] = useState(null);
  const [stockType, setStockType] = useState('in');
  const [stockForm] = Form.useForm();

  const fetchConsumables = useCallback(async (page = 1, pageSize = 10) => {
    try {
      setLoading(true);
      const response = await axios.get('/api/consumables', {
        params: { page, pageSize, keyword, category, status }
      });
      setConsumables(response.data.consumables);
      setPagination(prev => ({ ...prev, current: page, pageSize, total: response.data.total }));
    } catch (error) {
      message.error('获取耗材列表失败');
      console.error('获取耗材列表失败:', error);
    } finally {
      setLoading(false);
    }
  }, [keyword, category, status]);

  const fetchCategories = useCallback(async () => {
    try {
      const response = await axios.get('/api/consumable-categories/list');
      setCategories(response.data);
    } catch (error) {
      console.error('获取分类列表失败:', error);
    }
  }, []);

  useEffect(() => {
    fetchConsumables();
    fetchCategories();
  }, [fetchConsumables, fetchCategories]);

  const showModal = useCallback((consumable = null) => {
    setEditingConsumable(consumable);
    if (consumable) {
      form.setFieldsValue(consumable);
    } else {
      form.resetFields();
    }
    setModalVisible(true);
  }, [form]);

  const handleCancel = useCallback(() => {
    setModalVisible(false);
    setEditingConsumable(null);
  }, []);

  const handleSubmit = useCallback(async (values) => {
    try {
      if (editingConsumable) {
        await axios.put(`/api/consumables/${editingConsumable.consumableId}`, values);
        message.success('耗材更新成功');
      } else {
        await axios.post('/api/consumables', {
          ...values,
          consumableId: `CON${Date.now()}`
        });
        message.success('耗材创建成功');
      }
      setModalVisible(false);
      fetchConsumables();
      setEditingConsumable(null);
    } catch (error) {
      message.error(editingConsumable ? '耗材更新失败' : '耗材创建失败');
      console.error('提交失败:', error);
    }
  }, [editingConsumable, fetchConsumables]);

  const handleDelete = useCallback(async (consumableId) => {
    try {
      await axios.delete(`/api/consumables/${consumableId}`);
      message.success('删除成功');
      fetchConsumables();
    } catch (error) {
      message.error('删除失败');
      console.error('删除失败:', error);
    }
  }, [fetchConsumables]);

  const handleSearch = useCallback((value) => {
    setKeyword(value);
  }, []);

  const exportToCSV = (data, filename) => {
    const headers = ['耗材ID', '名称', '分类', '单位', '当前库存', '最小库存', '最大库存', '单价', '供应商', '存放位置', '状态'];
    const keys = ['consumableId', 'name', 'category', 'unit', 'currentStock', 'minStock', 'maxStock', 'unitPrice', 'supplier', 'location', 'status'];
    
    const csvContent = [
      headers.join(','),
      ...data.map(row => keys.map(key => {
        let value = row[key];
        if (key === 'unitPrice') value = `¥${parseFloat(value || 0).toFixed(2)}`;
        if (key === 'status') value = value === 'active' ? '启用' : '停用';
        if (value === null || value === undefined) value = '';
        const str = String(value);
        if (str.includes(',') || str.includes('"') || str.includes('\n')) {
          return `"${str.replace(/"/g, '""')}"`;
        }
        return str;
      }).join(','))
    ].join('\n');
    
    const blob = new Blob([csvContent], { type: 'text/csv;charset=utf-8;' });
    const url = window.URL.createObjectURL(blob);
    const link = document.createElement('a');
    link.href = url;
    link.download = filename;
    document.body.appendChild(link);
    link.click();
    document.body.removeChild(link);
    window.URL.revokeObjectURL(url);
  };

  const handleExport = async () => {
    try {
      const response = await axios.get('/api/consumables', {
        params: { keyword, category, status, pageSize: 1000 }
      });
      const consumables = response.data.consumables;
      exportToCSV(consumables, `consumables_${new Date().toISOString().split('T')[0]}.csv`);
      message.success('导出成功');
    } catch (error) {
      message.error('导出失败');
      console.error('导出失败:', error);
    }
  };

  const parseCSV = (text) => {
    const lines = text.trim().split('\n');
    if (lines.length < 2) return [];
    
    const headers = lines[0].split(',').map(h => h.trim().replace(/^"|"$/g, ''));
    const data = [];
    
    for (let i = 1; i < lines.length; i++) {
      const line = lines[i].trim();
      if (!line) continue;
      
      let values = [];
      let inQuotes = false;
      let current = '';
      
      for (let j = 0; j < line.length; j++) {
        const char = line[j];
        if (char === '"') {
          inQuotes = !inQuotes;
        } else if (char === ',' && !inQuotes) {
          values.push(current.trim().replace(/^"|"$/g, ''));
          current = '';
        } else {
          current += char;
        }
      }
      values.push(current.trim().replace(/^"|"$/g, ''));
      
      const row = {};
      headers.forEach((header, idx) => {
        row[header] = values[idx] || '';
      });
      data.push(row);
    }
    
    return data;
  };

  const handleFileChange = (info) => {
    const file = info.fileList[info.fileList.length - 1];
    if (file && file.originFileObj) {
      const reader = new FileReader();
      reader.onload = (e) => {
        const text = e.target.result;
        const parsedData = parseCSV(text);
        setImportPreview(parsedData.slice(0, 10));
        setImportFile(file.originFileObj);
      };
      reader.readAsText(file.originFileObj);
    }
  };

  const showImportModal = () => {
    setImportPreview([]);
    setImportFile(null);
    setImportModalVisible(true);
  };

  const handleImportCancel = () => {
    setImportModalVisible(false);
    setImportPreview([]);
    setImportFile(null);
    setImportProgress(0);
    setImportPhase('');
    setImportResult(null);
  };

  const handleImport = async () => {
    if (!importFile) {
      message.warning('请先选择文件');
      return;
    }
    
    setImporting(true);
    setImportProgress(0);
    setImportPhase('正在读取文件...');
    setImportResult(null);
    
    try {
      const reader = new FileReader();
      reader.onload = async (e) => {
        const text = e.target.result;
        setImportProgress(10);
        setImportPhase('正在读取文件...');
        
        setTimeout(() => {
          setImportProgress(20);
          setImportPhase('正在解析CSV数据...');
        }, 100);
        
        const items = parseCSV(text);
        const totalItems = items.length;
        
        setTimeout(() => {
          setImportProgress(30);
          setImportPhase(`共解析 ${totalItems} 条记录，准备提交...`);
        }, 200);
        
        setTimeout(() => {
          setImportProgress(40);
          setImportPhase('正在连接服务器...');
        }, 300);
        
        const response = await axios.post('/api/consumables/import', { items });
        
        setTimeout(() => {
          setImportProgress(60);
          setImportPhase('正在处理服务器响应...');
        }, 100);
        
        setTimeout(() => {
          setImportProgress(80);
          setImportPhase('正在更新本地数据...');
        }, 200);
        
        const results = response.data.results;
        
        setTimeout(() => {
          setImportResult(results);
          setImportProgress(100);
          setImportPhase('导入完成');
          setImporting(false);
          
          if (results.failed > 0) {
            message.warning(`导入完成，成功 ${results.success} 条，失败 ${results.failed} 条`);
          } else {
            message.success(response.data.message || `成功导入 ${results.success} 条记录`);
          }
        }, 300);
      };
      reader.onerror = () => {
        setImporting(false);
        setImportProgress(0);
        setImportPhase('文件读取失败');
        setImportResult({
          success: false,
          total: 0,
          imported: 0,
          failed: 0,
          errors: [{ row: '-', error: '文件读取失败，请检查文件是否损坏' }],
          message: '文件读取失败'
        });
        message.error('文件读取失败');
      };
      reader.readAsText(importFile);
    } catch (error) {
      setImporting(false);
      setImportProgress(0);
      setImportPhase('导入失败');
      
      let errorMessage = '导入失败，请检查网络连接或服务器状态';
      let errorDetails = [];
      
      if (error.response && error.response.data) {
        const { data } = error.response;
        if (data.errors && Array.isArray(data.errors) && data.errors.length > 0) {
          errorDetails = data.errors.map((err, index) => ({
            row: err.row || index + 1,
            error: err.error || err.message || '数据格式错误'
          }));
          errorMessage = `导入失败，共发现 ${errorDetails.length} 处数据错误`;
        } else if (data.message) {
          errorMessage = data.message;
        } else if (data.error) {
          errorMessage = data.error;
        }
      } else if (error.message) {
        if (error.message.includes('Network Error') || error.message.includes('network')) {
          errorMessage = '网络连接失败，请检查服务器是否运行';
        } else if (error.message.includes('timeout')) {
          errorMessage = '请求超时，请稍后重试';
        } else {
          errorMessage = error.message;
        }
      }
      
      setImportResult({
        success: false,
        total: 0,
        imported: 0,
        failed: 0,
        errors: errorDetails,
        message: errorMessage
      });
      
      message.error(errorMessage);
      console.error('导入耗材失败:', error);
    }
  };

  const downloadTemplate = () => {
    const template = '耗材ID,名称,分类,单位,当前库存,最小库存,最大库存,单价,供应商,存放位置,描述,状态\n,测试耗材,办公用品,个,100,10,500,5.00,XX公司,A柜-01层,测试数据,active';
    const blob = new Blob([template], { type: 'text/csv;charset=utf-8;' });
    const url = window.URL.createObjectURL(blob);
    const link = document.createElement('a');
    link.href = url;
    link.download = '耗材导入模板.csv';
    document.body.appendChild(link);
    link.click();
    document.body.removeChild(link);
    window.URL.revokeObjectURL(url);
  };

  const showStockModal = useCallback((record, type) => {
    setStockRecord(record);
    setStockType(type);
    stockForm.setFieldsValue({
      consumableId: record.consumableId,
      consumableName: record.name,
      quantity: 1,
      reason: '',
      notes: ''
    });
    setStockModalVisible(true);
  }, [stockForm]);

  const handleStockCancel = useCallback(() => {
    setStockModalVisible(false);
    setStockRecord(null);
  }, []);

  const handleStockSubmit = useCallback(async (values) => {
    try {
      const response = await axios.post('/api/consumables/quick-inout', {
        consumableId: stockRecord.consumableId,
        type: stockType,
        quantity: values.quantity,
        operator: values.operator || '系统管理员',
        reason: values.reason,
        notes: values.notes
      });
      message.success(`${stockType === 'in' ? '入库' : '出库'}操作成功`);
      setStockModalVisible(false);
      fetchConsumables();
    } catch (error) {
      message.error(error.response?.data?.error || `${stockType === 'in' ? '入库' : '出库'}操作失败`);
      console.error('操作失败:', error);
    }
  }, [stockRecord, stockType, fetchConsumables]);

  const columns = useMemo(() => [
    {
      title: '耗材ID',
      dataIndex: 'consumableId',
      key: 'consumableId',
      width: 150
    },
    {
      title: '名称',
      dataIndex: 'name',
      key: 'name',
      width: 150
    },
    {
      title: '分类',
      dataIndex: 'category',
      key: 'category',
      width: 120
    },
    {
      title: '单位',
      dataIndex: 'unit',
      key: 'unit',
      width: 80
    },
    {
      title: '当前库存',
      dataIndex: 'currentStock',
      key: 'currentStock',
      width: 100,
      render: (value, record) => {
        const isLow = value <= record.minStock;
        return (
          <span style={{ color: isLow ? '#ff4d4f' : '#52c41a', fontWeight: 'bold' }}>
            {value}
          </span>
        );
      }
    },
    {
      title: '最小库存',
      dataIndex: 'minStock',
      key: 'minStock',
      width: 100
    },
    {
      title: '最大库存',
      dataIndex: 'maxStock',
      key: 'maxStock',
      width: 100
    },
    {
      title: '单价(元)',
      dataIndex: 'unitPrice',
      key: 'unitPrice',
      width: 100,
      render: (value) => `¥${parseFloat(value || 0).toFixed(2)}`
    },
    {
      title: '供应商',
      dataIndex: 'supplier',
      key: 'supplier',
      width: 150,
      render: (value) => value || '-'
    },
    {
      title: '位置',
      dataIndex: 'location',
      key: 'location',
      width: 120,
      render: (value) => value || '-'
    },
    {
      title: '状态',
      dataIndex: 'status',
      key: 'status',
      width: 100,
      render: (value) => (
        <span style={{ color: value === 'active' ? '#52c41a' : '#ff4d4f' }}>
          {value === 'active' ? '启用' : '停用'}
        </span>
      )
    },
    {
      title: '操作',
      key: 'action',
      width: 200,
      render: (_, record) => (
        <Space>
          <Button type="primary" icon={<EditOutlined />} size="small" onClick={() => showModal(record)}>编辑</Button>
          <Button type="default" icon={<InboxOutlined />} size="small" style={{ background: '#f6ffed', borderColor: '#b7eb8f', color: '#52c41a' }} onClick={() => showStockModal(record, 'in')}>入库</Button>
          <Button type="default" icon={<ExportOutlined />} size="small" style={{ background: '#fff2f0', borderColor: '#ffccc7', color: '#ff4d4f' }} onClick={() => showStockModal(record, 'out')}>出库</Button>
          <Popconfirm title="确定删除?" onConfirm={() => handleDelete(record.consumableId)}>
            <Button danger icon={<DeleteOutlined />} size="small">删除</Button>
          </Popconfirm>
        </Space>
      )
    }
  ], [showModal, showStockModal, handleDelete]);

  const previewColumns = [
    { title: '名称', dataIndex: '名称', key: 'name', width: 120 },
    { title: '分类', dataIndex: '分类', key: 'category', width: 100 },
    { title: '单位', dataIndex: '单位', key: 'unit', width: 80 },
    { title: '当前库存', dataIndex: '当前库存', key: 'currentStock', width: 90 },
    { title: '单价', dataIndex: '单价', key: 'unitPrice', width: 80 }
  ];

  return (
    <div>
      <Card title="耗材管理" extra={
        <Space>
          <Button type="primary" icon={<PlusOutlined />} onClick={() => showModal()}>添加耗材</Button>
          <Button icon={<ImportOutlined />} onClick={showImportModal}>导入</Button>
          <Button icon={<ExportOutlined />} onClick={handleExport}>导出</Button>
        </Space>
      }>
        <Card size="small" style={{ marginBottom: 16 }}>
          <Space>
            <Input.Search
              placeholder="搜索耗材ID、名称、分类、供应商"
              style={{ width: 300 }}
              onSearch={handleSearch}
              allowClear
            />
            <Select value={category} onChange={setCategory} style={{ width: 150 }}>
              <Option value="all">所有分类</Option>
              {categories.map(cat => (
                <Option key={cat.id} value={cat.name}>{cat.name}</Option>
              ))}
            </Select>
            <Select value={status} onChange={setStatus} style={{ width: 120 }}>
              <Option value="all">所有状态</Option>
              <Option value="active">启用</Option>
              <Option value="inactive">停用</Option>
            </Select>
          </Space>
        </Card>

        <Table
          columns={columns}
          dataSource={consumables}
          rowKey="consumableId"
          loading={loading}
          pagination={pagination}
          onChange={(pagination) => fetchConsumables(pagination.current, pagination.pageSize)}
          scroll={{ x: 1300 }}
        />
      </Card>

      <Modal
        title={editingConsumable ? '编辑耗材' : '添加耗材'}
        open={modalVisible}
        onCancel={handleCancel}
        footer={null}
        width={600}
      >
        <Form form={form} layout="vertical" onFinish={handleSubmit}>
          <Form.Item name="name" label="名称" rules={[{ required: true, message: '请输入名称' }]}>
            <Input placeholder="请输入耗材名称" />
          </Form.Item>
          <Form.Item name="category" label="分类" rules={[{ required: true, message: '请选择分类' }]}>
            <Select
              placeholder="请选择分类"
              allowClear
            >
              {categories.map(cat => (
                <Option key={cat.id} value={cat.name}>{cat.name}</Option>
              ))}
            </Select>
          </Form.Item>
          <Form.Item name="unit" label="单位" rules={[{ required: true, message: '请输入单位' }]} initialValue="个">
            <Input placeholder="如: 个、盒、卷、箱" />
          </Form.Item>
          <Space style={{ width: '100%' }}>
            <Form.Item name="currentStock" label="当前库存" rules={[{ required: true, message: '请输入当前库存' }]}>
              <InputNumber min={0} style={{ width: '100%' }} />
            </Form.Item>
            <Form.Item name="minStock" label="最小库存" rules={[{ required: true, message: '请输入最小库存' }]}>
              <InputNumber min={0} style={{ width: '100%' }} />
            </Form.Item>
            <Form.Item name="maxStock" label="最大库存" rules={[{ required: true, message: '请输入最大库存' }]}>
              <InputNumber min={0} style={{ width: '100%' }} />
            </Form.Item>
          </Space>
          <Form.Item name="unitPrice" label="单价(元)">
            <InputNumber min={0} step={0.01} precision={2} style={{ width: '100%' }} placeholder="请输入单价" />
          </Form.Item>
          <Form.Item name="supplier" label="供应商">
            <Input placeholder="请输入供应商" />
          </Form.Item>
          <Form.Item name="location" label="存放位置">
            <Input placeholder="如: A柜-01层、B区货架3" />
          </Form.Item>
          <Form.Item name="description" label="描述">
            <Input.TextArea rows={3} placeholder="请输入描述信息" />
          </Form.Item>
          <Form.Item name="status" label="状态" rules={[{ required: true, message: '请选择状态' }]}>
            <Select>
              <Option value="active">启用</Option>
              <Option value="inactive">停用</Option>
            </Select>
          </Form.Item>
          <Form.Item>
            <Space>
              <Button type="primary" htmlType="submit">{editingConsumable ? '更新' : '创建'}</Button>
              <Button onClick={handleCancel}>取消</Button>
            </Space>
          </Form.Item>
        </Form>
      </Modal>

      <Modal
        title="导入耗材"
        open={importModalVisible}
        onCancel={handleImportCancel}
        footer={null}
        width={700}
      >
        <Space direction="vertical" style={{ width: '100%' }} size="middle">
          <Card size="small" style={{ background: '#f5f5f5' }}>
            <Space>
              <Button icon={<FileExcelOutlined />} onClick={downloadTemplate}>下载模板</Button>
              <span style={{ color: '#888', fontSize: 12 }}>请下载模板后填写数据再导入</span>
            </Space>
          </Card>
          
          <Upload
            accept=".csv"
            maxCount={1}
            beforeUpload={() => false}
            onChange={handleFileChange}
          >
            <Button icon={<UploadOutlined />}>选择CSV文件</Button>
          </Upload>
          
          {importPreview.length > 0 && (
            <div>
              <div style={{ marginBottom: 8, fontWeight: 'bold' }}>预览 (前10条):</div>
              <Table
                columns={previewColumns}
                dataSource={importPreview}
                rowKey={(record, index) => index}
                pagination={false}
                size="small"
                scroll={{ x: 500 }}
              />
            </div>
          )}
          
          <div style={{ textAlign: 'right' }}>
            <Space>
              <Button onClick={handleImportCancel}>取消</Button>
              <Button 
                type="primary" 
                onClick={handleImport} 
                loading={importing}
                disabled={!importFile}
              >
                开始导入
              </Button>
            </Space>
          </div>
        </Space>
      </Modal>

      <Modal
        title={stockType === 'in' ? '耗材入库' : '耗材出库'}
        open={stockModalVisible}
        onCancel={handleStockCancel}
        footer={null}
        width={500}
      >
        <Form form={stockForm} layout="vertical" onFinish={handleStockSubmit}>
          <Form.Item name="consumableId" label="耗材ID">
            <Input disabled />
          </Form.Item>
          <Form.Item name="consumableName" label="耗材名称">
            <Input disabled />
          </Form.Item>
          <Form.Item name="quantity" label="数量" rules={[{ required: true, message: '请输入数量' }]}>
            <InputNumber min={1} style={{ width: '100%' }} placeholder="请输入数量" />
          </Form.Item>
          <Form.Item name="operator" label="操作人">
            <Input placeholder="请输入操作人姓名" />
          </Form.Item>
          <Form.Item name="reason" label="入库/出库原因">
            <Input placeholder="如: 采购入库、部门领用、报损出库" />
          </Form.Item>
          <Form.Item name="notes" label="备注">
            <Input.TextArea rows={2} placeholder="请输入备注信息" />
          </Form.Item>
          <Form.Item>
            <Space>
              <Button type="primary" htmlType="submit">{stockType === 'in' ? '确认入库' : '确认出库'}</Button>
              <Button onClick={handleStockCancel}>取消</Button>
            </Space>
          </Form.Item>
        </Form>
      </Modal>
    </div>
  );
}

export default React.memo(ConsumableManagement);