import { NextRequest, NextResponse } from 'next/server';
import { getServiceClient } from '@/lib/supabase';

const MAX_FILE_SIZE = 5 * 1024 * 1024; // 5MB
const ALLOWED_TYPES = [
  'application/pdf',
  'application/msword',
  'application/vnd.openxmlformats-officedocument.wordprocessingml.document',
];

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

    if (!file) {
      return NextResponse.json(
        { error: 'No file provided' },
        { status: 400 }
      );
    }

    // Validate file size
    if (file.size > MAX_FILE_SIZE) {
      return NextResponse.json(
        { error: 'File size exceeds 5MB limit' },
        { status: 400 }
      );
    }

    // Validate file type
    if (!ALLOWED_TYPES.includes(file.type)) {
      return NextResponse.json(
        { error: 'Invalid file type. Accepted formats: PDF, DOC, DOCX' },
        { status: 400 }
      );
    }

    // Generate unique filename
    const timestamp = Date.now();
    const sanitizedName = file.name.replace(/[^a-zA-Z0-9._-]/g, '_');
    const filename = `${timestamp}_${sanitizedName}`;

    // Convert File to Buffer for upload
    const arrayBuffer = await file.arrayBuffer();
    const buffer = Buffer.from(arrayBuffer);

    const supabase = getServiceClient();

    // Upload to Supabase Storage
    const { data: uploadData, error: uploadError } = await supabase
      .storage
      .from('cvs')
      .upload(filename, buffer, {
        contentType: file.type,
        upsert: false,
      });

    if (uploadError) {
      console.error('Supabase storage upload error:', uploadError);
      return NextResponse.json(
        { error: 'Failed to upload file' },
        { status: 500 }
      );
    }

    // Get public URL
    const { data: urlData } = supabase
      .storage
      .from('cvs')
      .getPublicUrl(uploadData.path);

    return NextResponse.json({ url: urlData.publicUrl });
  } catch (error) {
    console.error('Upload CV error:', error);
    return NextResponse.json(
      { error: 'Internal server error' },
      { status: 500 }
    );
  }
}