/**
 * @copyright NHCarrigan
 * @license Naomi's Public License
 * @author Naomi Carrigan
 */

import { appendFileSync, existsSync, readFileSync } from "node:fs";

const filePath = "data/welcomed.txt";

const loadWelcomedMentees = (): Set<string> => {
  if (!existsSync(filePath)) {
    return new Set();
  }
  const contents = readFileSync(filePath, "utf-8");
  return new Set(contents.split("\n").filter(Boolean));
};

const welcomedMentees = loadWelcomedMentees();

/**
 * Appends a mentee's ID to the welcomed set and persists it to disk.
 * @param id - The Discord user ID to record.
 */
const addWelcomedMentee = (id: string): void => {
  welcomedMentees.add(id);
  appendFileSync(filePath, `${id}\n`);
};

export { addWelcomedMentee, welcomedMentees };