import bcrypt from 'bcrypt';
import crypto from 'crypto';

const SALT_ROUNDS = 12;

export async function hashPassword(password: string): Promise<string> {
  if (password.length < 8) {
    throw new Error('Пароль должен содержать минимум 8 символов');
  }

  const hasUpperCase = /[A-Z]/.test(password);
  const hasLowerCase = /[a-z]/.test(password);
  const hasNumbers = /\d/.test(password);
  const hasSpecialChar = /[!@#$%^&*(),.?":{}|<>]/.test(password);

  if (!hasUpperCase || !hasLowerCase || !hasNumbers || !hasSpecialChar) {
    throw new Error('Пароль должен содержать заглавные и строчные буквы, цифры и специальные символы');
  }

  return await bcrypt.hash(password, SALT_ROUNDS);
}

export async function verifyPassword(password: string, hash: string): Promise<boolean> {
  return await bcrypt.compare(password, hash);
}

export function generateTempPassword(): string {
  const lower = 'abcdefghijklmnopqrstuvwxyz';
  const upper = 'ABCDEFGHIJKLMNOPQRSTUVWXYZ';
  const digits = '0123456789';
  const special = '!@#$%^&*';
  const charset = lower + upper + digits + special;

  const pick = (set: string) => set[crypto.randomInt(set.length)];

  const chars: string[] = [
    pick(lower),
    pick(upper),
    pick(digits),
    pick(special),
    ...Array.from({ length: 8 }, () => pick(charset)),
  ];

  // Shuffle using Fisher-Yates with crypto.randomInt
  for (let i = chars.length - 1; i > 0; i--) {
    const j = crypto.randomInt(i + 1);
    [chars[i], chars[j]] = [chars[j], chars[i]];
  }

  return chars.join('');
}