import { NextRequest, NextResponse } from 'next/server';
import sharp from 'sharp';

const MAX_SIZE = 5 * 1024 * 1024; // 5MB
const OSS_URL = process.env.OSS_URL || 'http://localhost:9000';
const API_KEY = process.env.OSS_API_KEY || '7cf93760ea49b750c96e6078b364e5f0';

export async function POST(request: NextRequest) {
  let imageBuffer: Buffer;
  
  try {
    const formData = await request.formData();
    const file = formData.get('file') as File | null;

    if (!file) {
      return NextResponse.json({ error: '请选择图片' }, { status: 400 });
    }

    const allowedTypes = ['image/jpeg', 'image/png', 'image/gif', 'image/webp'];
    if (!allowedTypes.includes(file.type)) {
      return NextResponse.json({ error: '仅支持 JPG、PNG、GIF、WebP 格式' }, { status: 400 });
    }

    const buffer = await file.arrayBuffer();
    imageBuffer = Buffer.from(buffer);

    // 压缩图片
    const image = sharp(imageBuffer);
    const metadata = await image.metadata();

    if (imageBuffer.length > MAX_SIZE) {
      let quality = 85;

      if (metadata.width && metadata.width > 1920) {
        imageBuffer = await image
          .resize(1920, null, { withoutEnlargement: true })
          .toBuffer() as any;
      }

      while (imageBuffer.length > MAX_SIZE && quality > 30) {
        imageBuffer = await sharp(imageBuffer)
          .jpeg({ quality, progressive: true })
          .toBuffer() as any;
        quality -= 10;
      }

      if (imageBuffer.length > MAX_SIZE && metadata.width && metadata.width > 800) {
        imageBuffer = await sharp(imageBuffer)
          .resize(800, null, { withoutEnlargement: true })
          .jpeg({ quality: 70, progressive: true })
          .toBuffer() as any;
      }
    } else {
      imageBuffer = await sharp(imageBuffer)
        .jpeg({ quality: 85, progressive: true })
        .toBuffer() as any;
    }

    // 上传到 my_oss
    const formData2 = new FormData();
    const uint8Array = new Uint8Array(imageBuffer);
    const blob = new Blob([uint8Array], { type: 'image/jpeg' });
    formData2.append('file', blob, 'image.jpg');

    const uploadRes = await fetch(`${OSS_URL}/files`, {
      method: 'POST',
      headers: {
        'x-api-key': API_KEY,
      },
      body: formData2,
    });

    if (!uploadRes.ok) {
      const err = await uploadRes.text();
      console.error('OSS upload failed:', err);
      return NextResponse.json({ error: '上传失败' }, { status: 500 });
    }

    const fileData = await uploadRes.json();
    
    // 返回 my_oss 的访问URL
    const url = `${OSS_URL}/files/${fileData.fileKey}/preview`;
    return NextResponse.json({ url, fileKey: fileData.fileKey });
  } catch (error) {
    console.error('Upload error:', error);
    return NextResponse.json({ error: '上传失败' }, { status: 500 });
  }
}

export async function DELETE(request: NextRequest) {
  try {
    const { searchParams } = new URL(request.url);
    const fileKey = searchParams.get('fileKey');

    if (!fileKey) {
      return NextResponse.json({ error: '缺少文件标识' }, { status: 400 });
    }

    const res = await fetch(`${OSS_URL}/files/${fileKey}`, {
      method: 'DELETE',
      headers: {
        'x-api-key': API_KEY,
      },
    });

    if (res.ok) {
      return NextResponse.json({ success: true });
    }
    
    return NextResponse.json({ error: '删除失败' }, { status: 500 });
  } catch (error) {
    console.error('Delete error:', error);
    return NextResponse.json({ error: '删除失败' }, { status: 500 });
  }
}