import { NextRequest, NextResponse } from "next/server";
import { auth } from "@/auth";
import { db } from "@/lib/db";
import { uploadToHetzner } from "@/lib/storage";

function canManage(role: string) {
  return ["ADMIN", "PRODUCER", "SUPERVISOR"].includes(role);
}

// GET /api/sketch-templates — list all templates (any authenticated user)
export async function GET() {
  const session = await auth();
  if (!session?.user) return NextResponse.json({ error: "Unauthorized" }, { status: 401 });

  const templates = await db.sketchTemplate.findMany({
    orderBy: { sortOrder: "asc" },
  });

  return NextResponse.json({
    templates: templates.map((t) => ({
      ...t,
      fileSize: t.fileSize != null ? Number(t.fileSize) : null,
    })),
  });
}

// POST /api/sketch-templates — upload + create a new template
export async function POST(req: NextRequest) {
  const session = await auth();
  if (!session?.user) return NextResponse.json({ error: "Unauthorized" }, { status: 401 });
  if (!canManage(session.user.role))
    return NextResponse.json({ error: "Forbidden" }, { status: 403 });

  const formData = await req.formData();
  const file = formData.get("file") as File | null;
  const name = ((formData.get("name") as string) || "").trim();

  if (!file) return NextResponse.json({ error: "No file provided" }, { status: 400 });
  if (!file.type.startsWith("image/"))
    return NextResponse.json({ error: "Only image files accepted" }, { status: 400 });

  const maxSize = 20 * 1024 * 1024; // 20 MB
  if (file.size > maxSize)
    return NextResponse.json({ error: "File too large (max 20 MB)" }, { status: 413 });

  const buffer = Buffer.from(await file.arrayBuffer());
  const { key: tmplKey } = await uploadToHetzner(buffer, file.name, file.type, "image");
  const uploaded = { url: `/api/files/${tmplKey}`, key: tmplKey };

  const maxOrder = await db.sketchTemplate.aggregate({ _max: { sortOrder: true } });
  const sortOrder = (maxOrder._max.sortOrder ?? -1) + 1;

  const template = await db.sketchTemplate.create({
    data: {
      name: name || file.name.replace(/\.[^.]+$/, ""),
      fileUrl: uploaded.url,
      fileKey: uploaded.key,
      fileName: file.name,
      fileSize: BigInt(file.size),
      sortOrder,
    },
  });

  return NextResponse.json({
    template: { ...template, fileSize: Number(template.fileSize) },
  });
}