import { NextResponse } from "next/server";
import { auth } from "@clerk/nextjs/server";
import { ensureUserSynced } from "@/lib/sync-user";
import { getDatabase } from "@/lib/database";
import { isChatError, listThreadsForUser } from "@/lib/chat";
import log from "@/lib/logger";

interface Params {
  params: Promise<{ id: string }>;
}

export async function GET(_request: Request, { params }: Params) {
  try {
    const { userId } = await auth();
    if (!userId) {
      return NextResponse.json({ error: "Unauthorized" }, { status: 401 });
    }

    const { id: threadId } = await params;
    const db = await getDatabase();
    const currentUser = await ensureUserSynced(userId, db);
    if (!currentUser) {
      return NextResponse.json({ error: "Forbidden" }, { status: 403 });
    }

    const threads = await listThreadsForUser({
      id: currentUser.id,
      role: currentUser.role,
      gymId: currentUser.gymId,
    });

    const thread = threads.find((item) => item.id === threadId);
    if (!thread) {
      return NextResponse.json({ error: "Thread not found" }, { status: 404 });
    }

    return NextResponse.json({ thread });
  } catch (error) {
    if (isChatError(error)) {
      return NextResponse.json(
        { error: error.message },
        { status: error.status },
      );
    }

    log.error("Failed to fetch chat thread", error);
    return NextResponse.json(
      { error: "Internal server error" },
      { status: 500 },
    );
  }
}