const express = require('express');
const router = express.Router();
const path = require('path');
const fs = require('fs');

// 模拟PDF资料数据库（实际项目中应使用真实数据库）
const pdfMaterials = [
  {
    id: 1,
    aircraftId: 1,
    title: '波音737操作手册',
    fileName: 'B737_manual.pdf',
    description: '波音737详细操作手册',
    uploadDate: '2024-01-15',
    fileSize: '2.5MB'
  },
  {
    id: 2,
    aircraftId: 1,
    title: '波音737维护手册',
    fileName: 'B737_maintenance.pdf',
    description: '波音737维护保养手册',
    uploadDate: '2024-01-20',
    fileSize: '3.2MB'
  },
  {
    id: 3,
    aircraftId: 2,
    title: '空客A320操作手册',
    fileName: 'A320_manual.pdf',
    description: '空客A320详细操作手册',
    uploadDate: '2024-02-01',
    fileSize: '2.8MB'
  },
  {
    id: 4,
    aircraftId: 2,
    title: '空客A320技术规格',
    fileName: 'A320_specs.pdf',
    description: '空客A320技术规格说明',
    uploadDate: '2024-02-05',
    fileSize: '1.5MB'
  },
  {
    id: 5,
    aircraftId: 3,
    title: '波音787操作手册',
    fileName: 'B787_manual.pdf',
    description: '波音787详细操作手册',
    uploadDate: '2024-02-10',
    fileSize: '4.1MB'
  },
  {
    id: 6,
    aircraftId: 4,
    title: '空客A350操作手册',
    fileName: 'A350_manual.pdf',
    description: '空客A350详细操作手册',
    uploadDate: '2024-02-15',
    fileSize: '3.9MB'
  }
];

// 获取机型的PDF资料列表
router.get('/aircraft/:aircraftId', (req, res) => {
  try {
    const aircraftId = parseInt(req.params.aircraftId);
    const { search } = req.query;

    let materials = pdfMaterials.filter(m => m.aircraftId === aircraftId);

    if (search) {
      const searchLower = search.toLowerCase();
      materials = materials.filter(m => 
        m.title.toLowerCase().includes(searchLower) ||
        m.description.toLowerCase().includes(searchLower)
      );
    }

    res.json({
      success: true,
      data: materials
    });
  } catch (error) {
    console.error('获取PDF资料错误:', error);
    res.status(500).json({ error: '服务器内部错误' });
  }
});

// 获取所有PDF资料
router.get('/list', (req, res) => {
  try {
    const { search } = req.query;

    let materials = pdfMaterials;

    if (search) {
      const searchLower = search.toLowerCase();
      materials = materials.filter(m => 
        m.title.toLowerCase().includes(searchLower) ||
        m.description.toLowerCase().includes(searchLower)
      );
    }

    res.json({
      success: true,
      data: materials
    });
  } catch (error) {
    console.error('获取PDF资料列表错误:', error);
    res.status(500).json({ error: '服务器内部错误' });
  }
});

// 获取PDF文件URL（实际项目中应该检查文件是否存在）
router.get('/file/:id', (req, res) => {
  try {
    const id = parseInt(req.params.id);
    const material = pdfMaterials.find(m => m.id === id);

    if (!material) {
      return res.status(404).json({ error: '资料不存在' });
    }

    // 返回PDF文件的URL
    // 实际项目中，这里应该检查文件是否真实存在
    const fileUrl = `/uploads/${material.fileName}`;
    
    res.json({
      success: true,
      data: {
        id: material.id,
        title: material.title,
        fileUrl: fileUrl,
        fileName: material.fileName
      }
    });
  } catch (error) {
    console.error('获取PDF文件错误:', error);
    res.status(500).json({ error: '服务器内部错误' });
  }
});

module.exports = router;