import fs from "fs";
import path from "path";
import { NextResponse } from "next/server";
import { resolveMediaFile } from "@/lib/firmware";

export const dynamic = "force-dynamic";

const MIME: Record<string, string> = {
  ".png": "image/png",
  ".jpg": "image/jpeg",
  ".jpeg": "image/jpeg",
  ".webp": "image/webp",
  ".gif": "image/gif",
  ".mp4": "video/mp4",
  ".webm": "video/webm",
  ".md": "text/markdown; charset=utf-8",
  ".txt": "text/plain; charset=utf-8",
  ".html": "text/html; charset=utf-8",
  ".pdf": "application/pdf",
};

type Params = {
  params: Promise<{ project: string; variant: string; path: string[] }>;
};

export async function GET(_req: Request, { params }: Params) {
  const { project, variant, path: parts } = await params;
  const rel = parts.join("/");
  const abs = resolveMediaFile(project, variant, rel);
  if (!abs) {
    return NextResponse.json({ error: "not found" }, { status: 404 });
  }

  const ext = path.extname(abs).toLowerCase();
  const buf = fs.readFileSync(abs);
  return new NextResponse(buf, {
    headers: {
      "Content-Type": MIME[ext] || "application/octet-stream",
      "Content-Length": String(buf.length),
      "Cache-Control": "public, max-age=3600",
    },
  });
}