import { NextResponse } from "next/server";
import { requireAdmin } from "@/lib/auth";

const MAX_UPLOAD_BYTES = 1024 * 1024;

export async function POST(req: Request) {
  try {
    try {
      await requireAdmin();
    } catch {
      return NextResponse.json({ error: "Unauthorized" }, { status: 401 });
    }

    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 (!file.type.startsWith("image/")) {
      return NextResponse.json({ error: "Only image files are allowed" }, { status: 400 });
    }

    if (file.size > MAX_UPLOAD_BYTES) {
      return NextResponse.json({ error: "Image must be 1MB or smaller" }, { status: 400 });
    }

    const allowedExtensions = ["png", "jpg", "jpeg", "webp", "gif"];
    const originalExt = (file.name.split(".").pop() || "").toLowerCase();

    if (!allowedExtensions.includes(originalExt)) {
      return NextResponse.json({ error: "Invalid image extension" }, { status: 400 });
    }

    const buffer = Buffer.from(await file.arrayBuffer());
    const base64 = buffer.toString("base64");
    const mimeType = file.type;
    const dataUri = `data:${mimeType};base64,${base64}`;

    return NextResponse.json({ url: dataUri });
  } catch (error) {
    console.error("Upload error:", error);
    const message = error instanceof Error ? error.message : "Internal server error";
    return NextResponse.json({ error: message }, { status: 500 });
  }
}