import { TautulliUser } from "@/lib/types";
import { getSettings } from "@/lib/settings";

interface TautulliRow {
  friendly_name: string;
  email: string;
  plays: number;
  duration: number;
  last_seen: number | null;
}

interface TautulliResponse {
  response: {
    result: string;
    data: {
      data: TautulliRow[];
    };
  };
}

/**
 * Returns a Map<lowercaseEmail, TautulliUser>.
 * Returns null if TAUTULLI_URL/TAUTULLI_API are not set.
 */
export async function buildTautulliMap(): Promise<Map<string, TautulliUser> | null> {
  const { tautulli } = getSettings();
  const url = tautulli.url;
  const key = tautulli.apiKey;

  if (!url || !key) return null;

  const res = await fetch(
    `${url}/api/v2?apikey=${key}&cmd=get_users_table&length=1000&order_column=friendly_name&order_dir=asc`,
    { cache: "no-store" }
  );

  if (!res.ok) {
    throw new Error(`Tautulli API error: ${res.status} ${res.statusText}`);
  }

  const json: TautulliResponse = await res.json();

  if (json.response.result !== "success") {
    throw new Error(`Tautulli API returned non-success result`);
  }

  const map = new Map<string, TautulliUser>();

  for (const row of json.response.data.data) {
    const user: TautulliUser = {
      friendly_name: row.friendly_name,
      email: row.email ?? "",
      plays: row.plays ?? 0,
      duration: row.duration ?? 0,
      last_seen: row.last_seen ?? null,
    };

    if (user.email) {
      map.set(user.email.toLowerCase(), user);
    }
    // Also index by friendly_name as fallback key
    if (user.friendly_name) {
      map.set(`name:${user.friendly_name.toLowerCase()}`, user);
    }
  }

  return map;
}

export function lookupTautulliUser(
  tautulliMap: Map<string, TautulliUser>,
  email: string,
  displayName: string
): TautulliUser | null {
  return (
    tautulliMap.get(email.toLowerCase()) ??
    tautulliMap.get(`name:${displayName.toLowerCase()}`) ??
    null
  );
}