# frozen_string_literal: true

class RateLimiter::Redis < RateLimiter
  def get_global(name, ip)
    r = Cache.redis.get(global_key(name, ip))
    return r.to_i unless r.nil?
    nil
  end

  def get_route(name, domain, path, ip)
    r = Cache.redis.get(route_key(name, domain, path, ip))
    return r.to_i unless r.nil?
    nil
  end

  def get_global_ttl(name, ip)
    r = Cache.redis.pttl(global_key(name, ip))
    return nil if r.nil? || r < 0
    r
  end

  def get_route_ttl(name, domain, path, ip)
    r = Cache.redis.pttl(route_key(name, domain, path, ip))
    return nil if r.nil? || r < 0
    r
  end

  def consume_global(name, window, limit, ip)
    consume(global_key(name, ip), window, limit)
  end

  def consume_route(name, domain, path, window, limit, ip)
    consume(route_key(name, domain, path, ip), window, limit)
  end

  def fix_infinite_expiry(key, _val, expiry)
    Cache.redis.pexpire(key, expiry) if expiry.to_i == -1
  end

  private

  def consume(key, window, limit)
    exists = Cache.redis.exists(key) == 1
    Cache.redis.set(key, "0", px: window) unless exists
    val = Cache.redis.get(key).to_i
    exp = Cache.redis.pttl(key)
    fix_infinite_expiry(key, val, exp)
    # don't increase if the request will be rejected
    val > limit ? limit + 1 : Cache.redis.incr(key)
  end
end