<?php

namespace ace\helpers;
use \ace\Ace;
use \ace\core\HelperAbstract;
use \ace\helpers\Exception as HelperException;


class Protect extends HelperAbstract {

	public static function preventBruteForce($numRequests=4, $perSeconds=2000, $usePath=true, $bank=50){
		try {
			$key = md5($usePath ? REQUEST_PATH : $_SERVER['REQUEST_URI']);
			$fn = WEBROOT."/public-out/protect.preventBruteForce.$key";
			if (is_file($fn)) {
				$log = json_decode(file_get_contents($fn), true);
				if (!is_array($log))
					throw new HelperException(6010, null, 'json_decode()'); // 'Corrupted log file'
			} else {
				$log = array();
			}
			$call = array(
				't' => microtime(true),
				'r' => $_SERVER['REQUEST_URI'],
				'ip' => Ace::clientIp(),
				's' => 1,
			);
			if (!empty($log)) {
				if (!is_array($log))
					throw new HelperException(6010, null, 'list format'); // 'Corrupted log file'
				$mostDistantCallWithinRange = $log[min($numRequests,count($log))-1];
				if (!is_array($mostDistantCallWithinRange) || !is_numeric(Ace::g($mostDistantCallWithinRange,'t')))
					throw new HelperException(6010, null, 'item format'); // 'Corrupted log file'
				if ($call['t'] < $mostDistantCallWithinRange['t']+$perSeconds)
					$call['s'] = 0;
			}
			array_unshift($log, $call);
			while (count($log) > $bank)
				array_pop($log);
			if (!file_put_contents($fn, json_encode($log)))
				throw new HelperException(6015); // Failed to write to log file
			//if (!empty($_GET['debug'])) Ace::varDump($log);
			if ($call['s'] == 0)
				throw new HelperException(6017); // Too many requests
		} catch (\Exception $e) {
			echo $e->getMessage();
			exit;
		}
	}

}