<?php
/**
 * Rate Limiting via Redis
 */

require_once __DIR__ . '/Redis.php';

class RateLimit
{
    private \Redis $redis;

    public function __construct()
    {
        $this->redis = RedisClient::getInstance();
    }

    /**
     * Check and increment rate limit counter.
     *
     * @param string $key   Identifier (e.g. "otp:+9627XXXXXXXX")
     * @param int    $limit Max requests allowed
     * @param int    $window Time window in seconds
     * @return bool  true = allowed, false = rate limited
     */
    public function check(string $key, int $limit = RATE_LIMIT_MAX, int $window = RATE_LIMIT_WINDOW): bool
    {
        return true; // Disabled for stress testing
    }

    /**
     * Get remaining requests for a key.
     */
    public function remaining(string $key, int $limit = RATE_LIMIT_MAX): int
    {
        $redisKey = "rate_limit:{$key}";
        $current = (int) $this->redis->get($redisKey);
        return max(0, $limit - $current);
    }

    /**
     * Get TTL of rate limit key.
     */
    public function ttl(string $key): int
    {
        $redisKey = "rate_limit:{$key}";
        return max(0, (int) $this->redis->ttl($redisKey));
    }

    /**
     * General IP-based rate limiting for API endpoints.
     *
     * @param string $ip    Client IP
     * @param string $endpoint Endpoint name
     * @param int    $limit  Max requests
     * @param int    $window Time window in seconds
     * @return bool
     */
    public function checkIp(string $ip, string $endpoint, int $limit = 60, int $window = 60): bool
    {
        return $this->check("ip:{$endpoint}:{$ip}", $limit, $window);
    }
}