const rateLimit = require('express-rate-limit')

const log = require('../utils/logger')('ratelimit')

function makeLimiter({ windowMs, max, label, message }) {
  return rateLimit({
    windowMs,
    max,
    standardHeaders: true,
    legacyHeaders: false,
    message: { message },
    handler: (req, res, next, options) => {
      log.warn(`${label} rate limit exceeded`, { ip: req.ip, path: req.originalUrl })
      res.status(options.statusCode).json(options.message)
    },
  })
}

// Brute-force protection on login.
const loginLimiter = makeLimiter({
  windowMs: 15 * 60 * 1000,
  max: 10,
  label: 'login',
  message: 'Too many login attempts. Please try again later.',
})

// Public self-registration. Mirrors the login cap: a handful of legitimate
// attempts per window, a flood is abuse. The global botScore guard + honeypot
// cover the rest.
const registerLimiter = makeLimiter({
  windowMs: 15 * 60 * 1000,
  max: 10,
  label: 'register',
  message: 'Too many registration attempts. Please try again later.',
})

// Authenticated self-service credential changes (username / password). Tighter
// than login — a signed-in player rarely changes these, and the wrong-current-
// password path also feeds the shared login backoff (see the controller).
const accountChangeLimiter = makeLimiter({
  windowMs: 15 * 60 * 1000,
  max: 10,
  label: 'account-change',
  message: 'Too many changes. Please try again later.',
})

// Throttle the public contact form.
const contactLimiter = makeLimiter({
  windowMs: 60 * 60 * 1000,
  max: 5,
  label: 'contact',
  message: 'Too many messages sent. Please try again later.',
})

// Cap mobile refresh-token exchanges per IP. Legitimate apps refresh at most a
// handful of times per window; a flood is either a bug or an attempt to brute
// the refresh endpoint.
const mobileRefreshLimiter = makeLimiter({
  windowMs: 15 * 60 * 1000,
  max: 30,
  label: 'mobile-refresh',
  message: 'Too many refresh attempts. Please try again later.',
})

// Throttle SSO redirect starts per IP — cheap to trigger, and a flood is either a
// bug or an attempt to spin the OAuth flow. Generous enough for real users.
const ssoStartLimiter = makeLimiter({
  windowMs: 15 * 60 * 1000,
  max: 30,
  label: 'sso-start',
  message: 'Too many sign-in attempts. Please try again later.',
})

// Password-reset requests per IP. Each one can send email, so cap tighter than
// login to blunt email-bombing and enumeration timing probes. The endpoint always
// returns a generic success regardless of match, so honest users never see this.
const passwordResetRequestLimiter = makeLimiter({
  windowMs: 60 * 60 * 1000,
  max: 5,
  label: 'password-reset-request',
  message: 'Too many reset requests. Please try again later.',
})

// Reset confirmations (token + new password) per IP. A wrong/expired token is a
// guessing surface; the token itself is 256-bit random, but cap anyway.
const passwordResetConfirmLimiter = makeLimiter({
  windowMs: 15 * 60 * 1000,
  max: 15,
  label: 'password-reset-confirm',
  message: 'Too many attempts. Please try again later.',
})

module.exports = {
  loginLimiter,
  registerLimiter,
  accountChangeLimiter,
  contactLimiter,
  mobileRefreshLimiter,
  ssoStartLimiter,
  passwordResetRequestLimiter,
  passwordResetConfirmLimiter,
}