Momento/memento-note/lib/rate-limit.ts

import { redis } from '@/lib/redis'
import { NextResponse } from 'next/server'

const WINDOW_SECONDS = 60
const MAX_REQUESTS = 20

export async function rateLimit(
  userId: string,
  feature: string,
  max: number = MAX_REQUESTS,
  windowSec: number = WINDOW_SECONDS,
): Promise<{ allowed: boolean; remaining: number }> {
  const key = `ratelimit:${feature}:${userId}`
  try {
    const count = await redis.incr(key)
    if (count === 1) {
      await redis.expire(key, windowSec)
    }
    const remaining = Math.max(0, max - count)
    return { allowed: count <= max, remaining }
  } catch {
    return { allowed: true, remaining: max }
  }
}

export function rateLimitResponse(remaining: number): NextResponse | null {
  return null
}