<?php namespace EvolutionCMS\Support;

use EvolutionCMS\Interfaces\CaptchaInterface;

/**
 * ######
 * ## Verification Word
 * ######
 * ## This class generate an image with random text
 * ## to be used in form verification. It has visual
 * ## elements design to confuse OCR software preventing
 * ## the use of BOTS.
 * ##
 * #######
 * ## Author: Huda M Elmatsani
 * ## Email:   justhuda at netrada.co.id
 * ##
 * ## 25/07/2004
 * #######
 * ## Copyright (c) 2004 Huda M Elmatsani All rights reserved.
 * ## This program is free for any purpose use.
 * ########
 * ##
 * ## USAGE
 * ## create some image with noise texture, put in image directory,
 * ## rename to noise_#, see examples
 * ## put some true type font into font directory,
 * ## rename to font_#, see exmplae
 * ## you can search and put free font you like
 * ##
 * ## see sample.php for test and usage
 * ## sample URL: http://www.program-ruti.org/veriword/
 * ####
 */
class Captcha implements CaptchaInterface
{
    /* path to font directory*/
    public $dir_font   = "fonts/ttf/";
    /* path to background image directory*/
    public $dir_noise  = "captcha/";
    public $word       = "";
    public $im_width   = 0;
    public $im_height  = 0;
    public $im;

    public function __construct($w=200, $h=80) {
        /* create session to set word for verification */
        $this->setVeriword();
        $this->dir_font = MODX_BASE_PATH . 'assets/' . $this->dir_font;
        $this->im_width         = $w;
        $this->im_height        = $h;
    }

    public function setVeriword() {
        /* create session variable for verification,
           you may change the session variable name */
        $this->word             = $this->makeText();
        $_SESSION['veriword']   = $this->word;
    }

    public function output() {
        /* output the image as jpeg */
        $this->drawImage();
        header("Content-type: image/jpeg");
        imagejpeg($this->im);
    }

    public function makeText() {
        $modx = evolutionCMS();
        // set default words
        $words="MODX,Access,Better,BitCode,Chunk,Cache,Desc,Design,Excell,Enjoy,URLs,TechView,Gerald,Griff,Humphrey,Holiday,Intel,Integration,Joystick,Join(),Oscope,Genetic,Light,Likeness,Marit,Maaike,Niche,Netherlands,Ordinance,Oscillo,Parser,Phusion,Query,Question,Regalia,Righteous,Snippet,Sentinel,Template,Thespian,Unity,Enterprise,Verily,Veri,Website,WideWeb,Yap,Yellow,Zebra,Zygote";
        $words = $modx->getConfig('captcha_words', $words);
        $arr_words = array_filter(array_map('trim', explode(',', $words)));

        /* pick one randomly for text verification */
        return (string) $arr_words[array_rand($arr_words)].rand(10,999);
    }

    public function drawText() {
        $dir = dir($this->dir_font);
        $fontstmp = array();
        while (false !== ($file = $dir->read())) {
            if(substr($file, -4) == '.ttf') {
                $fontstmp[] = $this->dir_font.$file;
            }
        }
        $dir->close();
        $text_font = (string) $fontstmp[array_rand($fontstmp)];

        /* angle for text inclination */
        $text_angle = rand(-9,9);
        /* initial text size */
        $text_size  = 30;
        /* calculate text width and height */
        $box        = imagettfbbox ( $text_size, $text_angle, $text_font, $this->word);
        $text_width = $box[2]-$box[0]; //text width
        $text_height= $box[5]-$box[3]; //text height

        /* adjust text size */
        $text_size  = round((20 * $this->im_width)/$text_width);

        /* recalculate text width and height */
        $box        = imagettfbbox ( $text_size, $text_angle, $text_font, $this->word);
        $text_width = $box[2]-$box[0]; //text width
        $text_height= $box[5]-$box[3]; //text height

        /* calculate center position of text */
        $text_x         = ($this->im_width - $text_width)/2;
        $text_y         = ($this->im_height - $text_height)/2;

        /* create canvas for text drawing */
        $im_text        = imagecreate ($this->im_width, $this->im_height);
        $bg_color       = imagecolorallocate ($im_text, 255, 255, 255);

        /* pick color for text */
        $text_color     = imagecolorallocate ($im_text, 0, 51, 153);

        /* draw text into canvas */
        imagettftext    (   $im_text,
            $text_size,
            $text_angle,
            $text_x,
            $text_y,
            $text_color,
            $text_font,
            $this->word);

        /* remove background color */
        imagecolortransparent($im_text, $bg_color);
        return $im_text;
    }


    public function drawImage() {

        /* pick one background image randomly from image directory */
        $img_file       = MODX_BASE_PATH . 'assets/' . $this->dir_noise."noise".rand(1,4).".jpg";

        /* create "noise" background image from your image stock*/
        $noise_img      = @imagecreatefromjpeg ($img_file);
        $noise_width    = imagesx($noise_img);
        $noise_height   = imagesy($noise_img);

        /* resize the background image to fit the size of image output */
        $this->im       = imagecreatetruecolor($this->im_width,$this->im_height);
        imagecopyresampled ($this->im,
            $noise_img,
            0, 0, 0, 0,
            $this->im_width,
            $this->im_height,
            $noise_width,
            $noise_height);

        /* put text image into background image */
        imagecopymerge (    $this->im,
            $this->drawText(),
            0, 0, 0, 0,
            $this->im_width,
            $this->im_height,
            70 );

        return $this->im;
    }

    public function destroy() {
        imagedestroy($this->im);
    }
}
