/**
 * OSS 上传下载完整性测试
 * 
 * 测试流程：
 * 1. 读取本地 PDF 文件
 * 2. 上传到 OSS
 * 3. 从 OSS 下载
 * 4. 比较 MD5 值
 */

require('dotenv').config();
const fs = require('fs');
const crypto = require('crypto');
const OSS = require('ali-oss');

const testFile = 'D:\\MyCursor\\AIclinicalresearch\\docs\\06-测试文档\\近红外光谱（NIRS）队列研究举例.pdf';
const testKey = 'test/oss-integrity-test.pdf';

async function main() {
  console.log('='.repeat(60));
  console.log('OSS Upload/Download Integrity Test');
  console.log('='.repeat(60));

  // 1. 读取本地文件
  console.log('\n[1] Reading local file...');
  const localBuffer = fs.readFileSync(testFile);
  const localMd5 = crypto.createHash('md5').update(localBuffer).digest('hex');
  console.log(`  File size: ${localBuffer.length} bytes`);
  console.log(`  MD5: ${localMd5}`);
  console.log(`  First 20 bytes: ${localBuffer.slice(0, 20).toString('hex')}`);

  // 2. 创建 OSS 客户端
  console.log('\n[2] Creating OSS client...');
  const client = new OSS({
    region: process.env.OSS_REGION,
    bucket: process.env.OSS_BUCKET,
    accessKeyId: process.env.OSS_ACCESS_KEY_ID,
    accessKeySecret: process.env.OSS_ACCESS_KEY_SECRET,
    endpoint: `${process.env.OSS_REGION}.aliyuncs.com`,
    secure: true,
  });
  console.log(`  Region: ${process.env.OSS_REGION}`);
  console.log(`  Bucket: ${process.env.OSS_BUCKET}`);

  // 3. 上传到 OSS
  console.log('\n[3] Uploading to OSS...');
  try {
    const uploadResult = await client.put(testKey, localBuffer, {
      headers: {
        'Content-Type': 'application/pdf',
      },
    });
    console.log(`  Upload success: ${uploadResult.name}`);
  } catch (error) {
    console.error(`  Upload failed:`, error.message);
    return;
  }

  // 4. 从 OSS 下载
  console.log('\n[4] Downloading from OSS...');
  try {
    const downloadResult = await client.get(testKey);
    const downloadBuffer = downloadResult.content;
    const downloadMd5 = crypto.createHash('md5').update(downloadBuffer).digest('hex');
    
    console.log(`  Download size: ${downloadBuffer.length} bytes`);
    console.log(`  MD5: ${downloadMd5}`);
    console.log(`  First 20 bytes: ${downloadBuffer.slice(0, 20).toString('hex')}`);

    // 5. 比较
    console.log('\n[5] Comparing...');
    if (localMd5 === downloadMd5) {
      console.log('  ✅ MD5 MATCH - File integrity OK!');
    } else {
      console.log('  ❌ MD5 MISMATCH - File corrupted!');
      console.log(`     Local:    ${localMd5}`);
      console.log(`     Download: ${downloadMd5}`);
    }

    // 保存下载的文件用于对比
    const outputPath = 'D:\\MyCursor\\AIclinicalresearch\\docs\\06-测试文档\\oss-downloaded-test.pdf';
    fs.writeFileSync(outputPath, downloadBuffer);
    console.log(`\n  Downloaded file saved to: ${outputPath}`);

  } catch (error) {
    console.error(`  Download failed:`, error.message);
    return;
  }

  // 6. 清理
  console.log('\n[6] Cleanup...');
  try {
    await client.delete(testKey);
    console.log('  Test file deleted from OSS');
  } catch (error) {
    console.log(`  Cleanup failed: ${error.message}`);
  }

  console.log('\n' + '='.repeat(60));
  console.log('Test Complete!');
  console.log('='.repeat(60));
}

main().catch(console.error);