import { NextRequest, NextResponse } from "next/server";
import { auth } from "@clerk/nextjs/server";
import { S3Client, PutObjectCommand } from "@aws-sdk/client-s3";
import { v4 as uuidv4 } from "uuid";

const s3Client = new S3Client({
  endpoint: process.env.S3_ENDPOINT,
  region: process.env.S3_REGION || "eu-2",
  credentials: {
    accessKeyId: process.env.S3_ACCESS_KEY_ID!,
    secretAccessKey: process.env.S3_SECRET_ACCESS_KEY!,
  },
  forcePathStyle: true,
});

const S3_BUCKET = process.env.S3_BUCKET_NAME || "monuments-images";
const MAX_FILE_SIZE = 5 * 1024 * 1024;
const ALLOWED_TYPES = ["image/jpeg", "image/png", "image/webp", "image/gif"];

function getPublicUrl(key: string): string {
  return `/api/image?key=${encodeURIComponent(key)}`;
}

export async function POST(req: NextRequest) {
  const { userId } = await auth();
  if (!userId) {
    return NextResponse.json({ error: "Unauthorized" }, { status: 401 });
  }

  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 });
    }

    if (!ALLOWED_TYPES.includes(file.type)) {
      return NextResponse.json({ error: "Invalid file type" }, { status: 400 });
    }

    if (file.size > MAX_FILE_SIZE) {
      return NextResponse.json({ error: "File too large (max 5MB)" }, { status: 400 });
    }

    const ext = file.type.split("/")[1];
    const key = `uploads/${userId}/${uuidv4()}.${ext}`;
    const buffer = Buffer.from(await file.arrayBuffer());

    await s3Client.send(
      new PutObjectCommand({
        Bucket: S3_BUCKET,
        Key: key,
        Body: buffer,
        ContentType: file.type,
      })
    );

    const publicUrl = getPublicUrl(key);

    return NextResponse.json({ key, url: publicUrl });
  } catch (error) {
    console.error("Upload error:", error);
    return NextResponse.json({ error: "Upload failed" }, { status: 500 });
  }
}