import { NextResponse } from "next/server";
import { getSessionUser } from "@/lib/auth/get-session-user";
import { ensureProjectForOAuth } from "@/lib/db/assert-project";
import { createOAuthState, setOAuthCookies } from "@/lib/social/oauth-cookies";
import { buildYouTubeAuthUrl } from "@/lib/social/youtube-oauth";

const PREFIX = "youtube";

export async function GET(request: Request) {
  try {
    const user = await getSessionUser();
    if (!user) return NextResponse.json({ error: "Unauthorized" }, { status: 401 });

    const { searchParams } = new URL(request.url);
    const projectId = searchParams.get("projectId");
    const returnTo = searchParams.get("return") ?? "/connected-accounts";

    if (!projectId) {
      return NextResponse.json({ error: "projectId is required" }, { status: 400 });
    }

    await ensureProjectForOAuth({
      projectId,
      userId: user.id,
      email: user.email,
      name: user.name,
    });

    const state = createOAuthState();
    const url = buildYouTubeAuthUrl(state);
    const response = NextResponse.redirect(url);
    setOAuthCookies(response, PREFIX, {
      state,
      projectId,
      platform: "youtube",
      returnTo,
    });
    return response;
  } catch (error) {
    const message = error instanceof Error ? error.message : "YouTube OAuth failed";
    return NextResponse.json({ error: message }, { status: 500 });
  }
}