| 1 |  |  | <?php | 
                            
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                | 2 |  |  | /** | 
            
                                                                                                            
                            
            
                                    
            
            
                | 3 |  |  |  * @title          Captcha Class | 
            
                                                                                                            
                            
            
                                    
            
            
                | 4 |  |  |  * @desc           Generates a captcha and manages the display of the image. | 
            
                                                                                                            
                            
            
                                    
            
            
                | 5 |  |  |  * | 
            
                                                                                                            
                            
            
                                    
            
            
                | 6 |  |  |  * @author         Pierre-Henry Soria <[email protected]> | 
            
                                                                                                            
                            
            
                                    
            
            
                | 7 |  |  |  * @copyright      (c) 2012-2018, Pierre-Henry Soria. All Rights Reserved. | 
            
                                                                                                            
                            
            
                                    
            
            
                | 8 |  |  |  * @license        GNU General Public License; See PH7.LICENSE.txt and PH7.COPYRIGHT.txt in the root directory. | 
            
                                                                                                            
                            
            
                                    
            
            
                | 9 |  |  |  * @package        PH7 / Framework / Security / Spam / Captcha | 
            
                                                                                                            
                            
            
                                    
            
            
                | 10 |  |  |  * @version        0.9 | 
            
                                                                                                            
                            
            
                                    
            
            
                | 11 |  |  |  */ | 
            
                                                                                                            
                            
            
                                    
            
            
                | 12 |  |  |  | 
            
                                                                                                            
                            
            
                                    
            
            
                | 13 |  |  | namespace PH7\Framework\Security\Spam\Captcha; | 
            
                                                                                                            
                            
            
                                    
            
            
                | 14 |  |  |  | 
            
                                                                                                            
                            
            
                                    
            
            
                | 15 |  |  | defined('PH7') or exit('Restricted access'); | 
            
                                                                                                            
                            
            
                                    
            
            
                | 16 |  |  |  | 
            
                                                                                                            
                            
            
                                    
            
            
                | 17 |  |  | use PH7\Framework\Navigation\Browser; | 
            
                                                                                                            
                            
            
                                    
            
            
                | 18 |  |  | use PH7\Framework\Session\Session; | 
            
                                                                                                            
                            
            
                                    
            
            
                | 19 |  |  | use PH7\Framework\Util\Various; | 
            
                                                                                                            
                            
            
                                    
            
            
                | 20 |  |  |  | 
            
                                                                                                            
                            
            
                                    
            
            
                | 21 |  |  | class Captcha | 
            
                                                                                                            
                            
            
                                    
            
            
                | 22 |  |  | { | 
            
                                                                                                            
                            
            
                                    
            
            
                | 23 |  |  |     /** @var Session */ | 
            
                                                                                                            
                            
            
                                    
            
            
                | 24 |  |  |     private $oSession; | 
            
                                                                                                            
                            
            
                                    
            
            
                | 25 |  |  |  | 
            
                                                                                                            
                            
            
                                    
            
            
                | 26 |  |  |     /** @var Str */ | 
            
                                                                                                            
                            
            
                                    
            
            
                | 27 |  |  |     private $sStr; | 
            
                                                                                                            
                            
            
                                    
            
            
                | 28 |  |  |  | 
            
                                                                                                            
                            
            
                                    
            
            
                | 29 |  |  |     /** @var string */ | 
            
                                                                                                            
                            
            
                                    
            
            
                | 30 |  |  |     private $sFont; | 
            
                                                                                                            
                            
            
                                    
            
            
                | 31 |  |  |  | 
            
                                                                                                            
                            
            
                                    
            
            
                | 32 |  |  |     /** @var int */ | 
            
                                                                                                            
                            
            
                                    
            
            
                | 33 |  |  |     private $iStringWidth; | 
            
                                                                                                            
                            
            
                                    
            
            
                | 34 |  |  |  | 
            
                                                                                                            
                            
            
                                    
            
            
                | 35 |  |  |     /** @var int */ | 
            
                                                                                                            
                            
            
                                    
            
            
                | 36 |  |  |     private $iHeight; | 
            
                                                                                                            
                            
            
                                    
            
            
                | 37 |  |  |  | 
            
                                                                                                            
                            
            
                                    
            
            
                | 38 |  |  |     /** @var int */ | 
            
                                                                                                            
                            
            
                                    
            
            
                | 39 |  |  |     private $iWidth; | 
            
                                                                                                            
                            
            
                                    
            
            
                | 40 |  |  |  | 
            
                                                                                                            
                            
            
                                    
            
            
                | 41 |  |  |     /** @var int */ | 
            
                                                                                                            
                            
            
                                    
            
            
                | 42 |  |  |     private $iSize = 36; | 
            
                                                                                                            
                            
            
                                    
            
            
                | 43 |  |  |  | 
            
                                                                                                            
                            
            
                                    
            
            
                | 44 |  |  |     /** @var int */ | 
            
                                                                                                            
                            
            
                                    
            
            
                | 45 |  |  |     private $iMargin = 25; | 
            
                                                                                                            
                            
            
                                    
            
            
                | 46 |  |  |  | 
            
                                                                                                            
                            
            
                                    
            
            
                | 47 |  |  |     /** @var array */ | 
            
                                                                                                            
                            
            
                                    
            
            
                | 48 |  |  |     private $aBox; | 
            
                                                                                                            
                            
            
                                    
            
            
                | 49 |  |  |  | 
            
                                                                                                            
                            
            
                                    
            
            
                | 50 |  |  |     /** @var array */ | 
            
                                                                                                            
                            
            
                                    
            
            
                | 51 |  |  |     private static $aMatrixBlur = [ | 
            
                                                                                                            
                            
            
                                    
            
            
                | 52 |  |  |         [1, 1, 1], | 
            
                                                                                                            
                            
            
                                    
            
            
                | 53 |  |  |         [1, 1, 1], | 
            
                                                                                                            
                            
            
                                    
            
            
                | 54 |  |  |         [1, 1, 1] | 
            
                                                                                                            
                            
            
                                    
            
            
                | 55 |  |  |     ]; | 
            
                                                                                                            
                            
            
                                    
            
            
                | 56 |  |  |  | 
            
                                                                                                            
                            
            
                                    
            
            
                | 57 |  |  |     /** @var array */ | 
            
                                                                                                            
                            
            
                                    
            
            
                | 58 |  |  |     private $aColor = []; | 
            
                                                                                                            
                            
            
                                    
            
            
                | 59 |  |  |  | 
            
                                                                                                            
                            
            
                                    
            
            
                | 60 |  |  |     /** @var resource */ | 
            
                                                                                                            
                            
            
                                    
            
            
                | 61 |  |  |     private $rImg; | 
            
                                                                                                            
                            
            
                                    
            
            
                | 62 |  |  |  | 
            
                                                                                                            
                            
            
                                    
            
            
                | 63 |  |  |     /** @var resource */ | 
            
                                                                                                            
                            
            
                                    
            
            
                | 64 |  |  |     private $rBlack; | 
            
                                                                                                            
                            
            
                                    
            
            
                | 65 |  |  |  | 
            
                                                                                                            
                            
            
                                    
            
            
                | 66 |  |  |     /** @var resource */ | 
            
                                                                                                            
                            
            
                                    
            
            
                | 67 |  |  |     private $rRed; | 
            
                                                                                                            
                            
            
                                    
            
            
                | 68 |  |  |  | 
            
                                                                                                            
                            
            
                                    
            
            
                | 69 |  |  |     /** @var resource */ | 
            
                                                                                                            
                            
            
                                    
            
            
                | 70 |  |  |     private $rWhite; | 
            
                                                                                                            
                            
            
                                    
            
            
                | 71 |  |  |  | 
            
                                                                                                            
                            
            
                                    
            
            
                | 72 |  |  |     public function __construct() | 
            
                                                                                                            
                            
            
                                    
            
            
                | 73 |  |  |     { | 
            
                                                                                                            
                            
            
                                    
            
            
                | 74 |  |  |         $this->oSession = new Session; | 
            
                                                                                                            
                            
            
                                    
            
            
                | 75 |  |  |     } | 
            
                                                                                                            
                            
            
                                    
            
            
                | 76 |  |  |  | 
            
                                                                                                            
                            
            
                                    
            
            
                | 77 |  |  |     /** | 
            
                                                                                                            
                            
            
                                    
            
            
                | 78 |  |  |      * Show the captcha image. | 
            
                                                                                                            
                            
            
                                    
            
            
                | 79 |  |  |      * | 
            
                                                                                                            
                            
            
                                    
            
            
                | 80 |  |  |      * @param int $iRandom | 
            
                                                                                                            
                            
            
                                    
            
            
                | 81 |  |  |      * | 
            
                                                                                                            
                            
            
                                    
            
            
                | 82 |  |  |      * @return void | 
            
                                                                                                            
                            
            
                                    
            
            
                | 83 |  |  |      */ | 
            
                                                                                                            
                            
            
                                    
            
            
                | 84 |  |  |     public function show($iRandom = null) | 
            
                                                                                                            
                            
            
                                    
            
            
                | 85 |  |  |     { | 
            
                                                                                                            
                            
            
                                    
            
            
                | 86 |  |  |         if (!empty($iRandom)) { | 
            
                                                                                                            
                            
            
                                    
            
            
                | 87 |  |  |             $this->sStr = Various::genRnd($iRandom, 5); | 
            
                                                                                                            
                            
            
                                    
            
            
                | 88 |  |  |         } else { | 
            
                                                                                                            
                            
            
                                    
            
            
                | 89 |  |  |             $this->sStr = Various::genRnd('pH7_Pierre-Henry_Soria_Sanz_González_captcha', 5); | 
            
                                                                                                            
                            
            
                                    
            
            
                | 90 |  |  |         } | 
            
                                                                                                            
                            
            
                                    
            
            
                | 91 |  |  |  | 
            
                                                                                                            
                            
            
                                    
            
            
                | 92 |  |  |         $this->oSession->set('rand_code', $this->sStr); | 
            
                                                                                                            
                            
            
                                    
            
            
                | 93 |  |  |  | 
            
                                                                                                            
                            
            
                                    
            
            
                | 94 |  |  |         $this->sFont = $this->getFont(); | 
            
                                                                                                            
                            
            
                                    
            
            
                | 95 |  |  |         //$sBackground = PH7_PATH_DATA . 'background/' . mt_rand(1, 5) . '.png'; | 
                            
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                | 96 |  |  |  | 
            
                                                                                                            
                            
            
                                    
            
            
                | 97 |  |  |         $this->aBox = imagettfbbox($this->iSize, 0, $this->sFont, $this->sStr); | 
            
                                                                                                            
                            
            
                                    
            
            
                | 98 |  |  |         $this->iWidth = $this->aBox[2] - $this->aBox[0]; | 
                            
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                | 99 |  |  |         $this->iHeight = $this->aBox[1] - $this->aBox[7]; | 
                            
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                | 100 |  |  |         unset($this->aBox); | 
            
                                                                                                            
                            
            
                                    
            
            
                | 101 |  |  |  | 
            
                                                                                                            
                            
            
                                    
            
            
                | 102 |  |  |         $this->iStringWidth = round($this->iWidth / strlen($this->sStr)); | 
                            
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                | 103 |  |  |  | 
            
                                                                                                            
                            
            
                                    
            
            
                | 104 |  |  |         //$this->rImg = imagecreatefrompng($sBackground); | 
                            
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                | 105 |  |  |         $this->rImg = imagecreate($this->iWidth + $this->iMargin, $this->iHeight + $this->iMargin); | 
            
                                                                                                            
                            
            
                                    
            
            
                | 106 |  |  |         $this->aColor = [ | 
            
                                                                                                            
                            
            
                                    
            
            
                | 107 |  |  |             imagecolorallocate($this->rImg, 0x99, 0x00, 0x66), | 
            
                                                                                                            
                            
            
                                    
            
            
                | 108 |  |  |             imagecolorallocate($this->rImg, 0xCC, 0x00, 0x00), | 
            
                                                                                                            
                            
            
                                    
            
            
                | 109 |  |  |             imagecolorallocate($this->rImg, 0x00, 0x00, 0xCC), | 
            
                                                                                                            
                            
            
                                    
            
            
                | 110 |  |  |             imagecolorallocate($this->rImg, 0x00, 0x00, 0xCC), | 
            
                                                                                                            
                            
            
                                    
            
            
                | 111 |  |  |             imagecolorallocate($this->rImg, 0xBB, 0x88, 0x77) | 
            
                                                                                                            
                            
            
                                    
            
            
                | 112 |  |  |         ]; | 
            
                                                                                                            
                            
            
                                    
            
            
                | 113 |  |  |  | 
            
                                                                                                            
                            
            
                                    
            
            
                | 114 |  |  |         $this->rBlack = imagecolorallocate($this->rImg, 0, 0, 0); | 
                            
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                | 115 |  |  |         $this->rRed = imagecolorallocate($this->rImg, 200, 100, 90); | 
                            
                    |  |  |  | 
                                                                                        
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                | 116 |  |  |         $this->rWhite = imagecolorallocate($this->rImg, 255, 255, 255); | 
                            
                    |  |  |  | 
                                                                                        
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                | 117 |  |  |  | 
            
                                                                                                            
                            
            
                                    
            
            
                | 118 |  |  |         imagefilledrectangle($this->rImg, 0, 0, 399, 99, $this->rWhite); | 
            
                                                                                                            
                            
            
                                    
            
            
                | 119 |  |  |  | 
            
                                                                                                            
                            
            
                                    
            
            
                | 120 |  |  |         $this->mixing(); | 
            
                                                                                                            
                            
            
                                    
            
            
                | 121 |  |  |  | 
            
                                                                                                            
                            
            
                                    
            
            
                | 122 |  |  |         imageline($this->rImg, mt_rand(2, $this->iWidth + $this->iMargin), mt_rand(1, $this->iWidth + $this->iMargin), mt_rand(1, $this->iHeight + $this->iMargin), mt_rand(2, $this->iWidth + $this->iMargin), $this->rBlack); | 
            
                                                                                                            
                            
            
                                    
            
            
                | 123 |  |  |         imageline($this->rImg, mt_rand(2, $this->iHeight + $this->iMargin), mt_rand(1, $this->iHeight + $this->iMargin), mt_rand(1, $this->iWidth + $this->iMargin), mt_rand(2, $this->iHeight + $this->iMargin), $this->rRed); | 
            
                                                                                                            
                            
            
                                    
            
            
                | 124 |  |  |         imageline($this->rImg, mt_rand(2, $this->iHeight + $this->iMargin), mt_rand(1, $this->iWidth + $this->iMargin), mt_rand(1, $this->iWidth + $this->iMargin), mt_rand(2, $this->iHeight + $this->iMargin), $this->aColor[array_rand($this->aColor)]); | 
            
                                                                                                            
                            
            
                                    
            
            
                | 125 |  |  |         unset($this->rBlack, $this->rRed, $this->rWhite); | 
            
                                                                                                            
                            
            
                                    
            
            
                | 126 |  |  |  | 
            
                                                                                                            
                            
            
                                    
            
            
                | 127 |  |  |  | 
            
                                                                                                            
                            
            
                                    
            
            
                | 128 |  |  |         imageconvolution($this->rImg, self::$aMatrixBlur, 9, 0); | 
            
                                                                                                            
                            
            
                                    
            
            
                | 129 |  |  |         imageconvolution($this->rImg, self::$aMatrixBlur, 9, 0); | 
            
                                                                                                            
                            
            
                                    
            
            
                | 130 |  |  |  | 
            
                                                                                                            
                            
            
                                    
            
            
                | 131 |  |  |         (new Browser)->noCache(); | 
            
                                                                                                            
                            
            
                                    
            
            
                | 132 |  |  |         header('Content-type: image/png'); | 
            
                                                                                                            
                            
            
                                    
            
            
                | 133 |  |  |         imagepng($this->rImg); | 
            
                                                                                                            
                            
            
                                    
            
            
                | 134 |  |  |         imagedestroy($this->rImg); | 
            
                                                                                                            
                            
            
                                    
            
            
                | 135 |  |  |     } | 
            
                                                                                                            
                            
            
                                    
            
            
                | 136 |  |  |  | 
            
                                                                                                            
                            
            
                                    
            
            
                | 137 |  |  |     /** | 
            
                                                                                                            
                            
            
                                    
            
            
                | 138 |  |  |      * @param string $sCode The random code. | 
            
                                                                                                            
                            
            
                                    
            
            
                | 139 |  |  |      * | 
            
                                                                                                            
                            
            
                                    
            
            
                | 140 |  |  |      * @return bool | 
            
                                                                                                            
                            
            
                                    
            
            
                | 141 |  |  |      */ | 
            
                                                                                                            
                            
            
                                    
            
            
                | 142 |  |  |     public function check($sCode) | 
            
                                                                                                            
                            
            
                                    
            
            
                | 143 |  |  |     { | 
            
                                                                                                            
                            
            
                                    
            
            
                | 144 |  |  |         if ($sCode === null) { | 
            
                                                                                                            
                            
            
                                    
            
            
                | 145 |  |  |             return false; | 
            
                                                                                                            
                            
            
                                    
            
            
                | 146 |  |  |         } | 
            
                                                                                                            
                            
            
                                    
            
            
                | 147 |  |  |  | 
            
                                                                                                            
                            
            
                                    
            
            
                | 148 |  |  |         if ($sCode === $this->oSession->get('rand_code')) { | 
            
                                                                                                            
                            
            
                                    
            
            
                | 149 |  |  |             return true; | 
            
                                                                                                            
                            
            
                                    
            
            
                | 150 |  |  |         } | 
            
                                                                                                            
                            
            
                                    
            
            
                | 151 |  |  |  | 
            
                                                                                                            
                            
            
                                    
            
            
                | 152 |  |  |         return false; | 
            
                                                                                                            
                            
            
                                    
            
            
                | 153 |  |  |     } | 
            
                                                                                                            
                            
            
                                    
            
            
                | 154 |  |  |  | 
            
                                                                                                            
                            
            
                                    
            
            
                | 155 |  |  |     /** | 
            
                                                                                                            
                            
            
                                    
            
            
                | 156 |  |  |      * The HTML code for displaying the captcha. | 
            
                                                                                                            
                            
            
                                    
            
            
                | 157 |  |  |      * | 
            
                                                                                                            
                            
            
                                    
            
            
                | 158 |  |  |      * @return void | 
            
                                                                                                            
                            
            
                                    
            
            
                | 159 |  |  |      */ | 
            
                                                                                                            
                            
            
                                    
            
            
                | 160 |  |  |     public function display() | 
            
                                                                                                            
                            
            
                                    
            
            
                | 161 |  |  |     { | 
            
                                                                                                            
                            
            
                                    
            
            
                | 162 |  |  |         // Md5 parameter in the img tag to the captcha that the browser does not cache the captcha | 
            
                                                                                                            
                            
            
                                    
            
            
                | 163 |  |  |         echo // The captcha stylesheet that is now in the file form.css | 
            
                                                                                                            
                            
            
                                    
            
            
                | 164 |  |  |         '<div class="center"> | 
            
                                                                                                            
                            
            
                                    
            
            
                | 165 |  |  |            <img class="border captcha" src="', PH7_URL_ROOT, 'asset/file/captcha/?r=', md5(time()), '" id="captcha" alt="Captcha Image" /> | 
            
                                                                                                            
                            
            
                                    
            
            
                | 166 |  |  |            <a class="captcha_button" href="#" onclick="document.getElementById(\'captcha\').src =\'', PH7_URL_ROOT, 'asset/file/captcha/?r=\' + Math.random(); return false"><img src="', PH7_URL_STATIC, PH7_IMG, 'icon/reload.png" onclick="this.blur()" id="refresh" alt="Refresh Image" title="Refresh Image" /></a> | 
            
                                                                                                            
                            
            
                                    
            
            
                | 167 |  |  |          </div>'; | 
            
                                                                                                            
                            
            
                                    
            
            
                | 168 |  |  |     } | 
            
                                                                                                            
                            
            
                                    
            
            
                | 169 |  |  |  | 
            
                                                                                                            
                            
            
                                    
            
            
                | 170 |  |  |     /** | 
            
                                                                                                            
                            
            
                                    
            
            
                | 171 |  |  |      * @return void | 
            
                                                                                                            
                            
            
                                    
            
            
                | 172 |  |  |      */ | 
            
                                                                                                            
                            
            
                                    
            
            
                | 173 |  |  |     private function mixing() | 
            
                                                                                                            
                            
            
                                    
            
            
                | 174 |  |  |     { | 
            
                                                                                                            
                            
            
                                    
            
            
                | 175 |  |  |         for ($i = 0, $iLength = strlen($this->sStr); $i < $iLength; ++$i) { | 
            
                                                                                                            
                            
            
                                    
            
            
                | 176 |  |  |             $sText = $this->sStr[$i]; // A string can be seen as an array | 
            
                                                                                                            
                            
            
                                    
            
            
                | 177 |  |  |             $iAngle = mt_rand(-70, 70); | 
            
                                                                                                            
                            
            
                                    
            
            
                | 178 |  |  |  | 
            
                                                                                                            
                            
            
                                    
            
            
                | 179 |  |  |             imagettftext( | 
            
                                                                                                            
                            
            
                                    
            
            
                | 180 |  |  |                 $this->rImg, | 
            
                                                                                                            
                            
            
                                    
            
            
                | 181 |  |  |                 mt_rand($this->iSize / 2, $this->iSize), | 
            
                                                                                                            
                            
            
                                    
            
            
                | 182 |  |  |                 $iAngle, | 
            
                                                                                                            
                            
            
                                    
            
            
                | 183 |  |  |                 ($i * $this->iStringWidth) + $this->iMargin, | 
            
                                                                                                            
                            
            
                                    
            
            
                | 184 |  |  |                 $this->iHeight + mt_rand(1, $this->iMargin / 2), | 
            
                                                                                                            
                            
            
                                    
            
            
                | 185 |  |  |                 $this->aColor[array_rand($this->aColor)], | 
            
                                                                                                            
                            
            
                                    
            
            
                | 186 |  |  |                 $this->sFont, | 
            
                                                                                                            
                            
            
                                    
            
            
                | 187 |  |  |                 $sText | 
            
                                                                                                            
                            
            
                                    
            
            
                | 188 |  |  |             ); | 
            
                                                                                                            
                            
            
                                    
            
            
                | 189 |  |  |         } | 
            
                                                                                                            
                            
            
                                    
            
            
                | 190 |  |  |     } | 
            
                                                                                                            
                            
            
                                    
            
            
                | 191 |  |  |  | 
            
                                                                                                            
                            
            
                                    
            
            
                | 192 |  |  |     /** | 
            
                                                                                                            
                            
            
                                    
            
            
                | 193 |  |  |      * @return string The font path of captcha. | 
            
                                                                                                            
                                                                
            
                                    
            
            
                | 194 |  |  |      */ | 
            
                                                        
            
                                    
            
            
                | 195 |  |  |     private function getFont() | 
            
                                                        
            
                                    
            
            
                | 196 |  |  |     { | 
            
                                                        
            
                                    
            
            
                | 197 |  |  |         //$count = count(glob(PH7_PATH_DATA . '/font/*.ttf')); | 
                            
                    |  |  |  | 
                                                                                        
                                                                                     | 
            
                                                        
            
                                    
            
            
                | 198 |  |  |         //return PH7_PATH_DATA . '/font/' . mt_rand(1,$count) . '.ttf'; | 
                            
                    |  |  |  | 
                                                                                        
                                                                                     | 
            
                                                        
            
                                    
            
            
                | 199 |  |  |         return PH7_PATH_DATA . '/font/4.ttf'; | 
            
                                                        
            
                                    
            
            
                | 200 |  |  |     } | 
            
                                                        
            
                                    
            
            
                | 201 |  |  | } | 
            
                                                        
            
                                    
            
            
                | 202 |  |  |  | 
            
                        
The PSR-1: Basic Coding Standard recommends that a file should either introduce new symbols, that is classes, functions, constants or similar, or have side effects. Side effects are anything that executes logic, like for example printing output, changing ini settings or writing to a file.
The idea behind this recommendation is that merely auto-loading a class should not change the state of an application. It also promotes a cleaner style of programming and makes your code less prone to errors, because the logic is not spread out all over the place.
To learn more about the PSR-1, please see the PHP-FIG site on the PSR-1.