import argon2 from 'argon2'

// --- Hash a password (e.g. at signup) ---
export async function hashPassword(plainPassword) {
  try {
    const hash = await argon2.hash(plainPassword, {
      type: argon2.argon2id,   // recommended variant
      memoryCost: 2 ** 16,     // ~64 MB
      timeCost: 3,             // iterations
      parallelism: 1           // threads
    })
    return hash  // store this string in MySQL
  } catch (err) {
    console.error('Error hashing password:', err)
    throw err
  }
}

// --- Verify a password (e.g. at login) ---
export async function verifyPassword(plainPassword, storedHash) {
  try {
    const match = await argon2.verify(storedHash, plainPassword)
    return match // true or false
  } catch (err) {
    console.error('Error verifying password:', err)
    return false
  }
}