1:   2:   3:   4:   5:   6:   7:   8:   9:  10:  11:  12:  13:  14:  15:  16:  17:  18:  19:  20:  21:  22:  23:  24:  25:  26:  27:  28:  29:  30:  31:  32:  33:  34:  35:  36:  37:  38:  39:  40:  41:  42:  43:  44:  45:  46:  47:  48:  49:  50:  51:  52:  53:  54:  55:  56:  57:  58:  59:  60:  61:  62:  63:  64:  65:  66:  67:  68:  69:  70:  71:  72:  73:  74:  75:  76:  77:  78:  79:  80:  81:  82:  83:  84:  85:  86:  87:  88:  89:  90:  91:  92:  93:  94:  95:  96:  97:  98:  99: 100: 101: 102: 103: 104: 105: 106: 107: 108: 109: 110: 111: 112: 113: 114: 115: 116: 117: 118: 119: 120: 121: 122: 123: 124: 125: 126: 127: 128: 129: 130: 131: 132: 133: 134: 135: 136: 137: 138: 139: 140: 141: 142: 143: 144: 145: 146: 147: 148: 149: 150: 151: 152: 153: 154: 155: 156: 157: 158: 159: 160: 161: 162: 163: 164: 165: 166: 167: 168: 169: 170: 171: 172: 173: 174: 175: 176: 177: 178: 179: 180: 181: 182: 183: 184: 185: 186: 187: 188: 189: 190: 191: 192: 193: 194: 195: 196: 197: 198: 199: 200: 201: 202: 203: 204: 205: 206: 207: 208: 209: 210: 211: 212: 213: 214: 215: 216: 217: 218: 219: 220: 221: 222: 223: 224: 225: 226: 227: 228: 229: 230: 231: 232: 233: 234: 235: 236: 237: 238: 239: 240: 241: 242: 243: 244: 245: 246: 247: 248: 249: 250: 251: 252: 253: 254: 255: 256: 257: 258: 259: 260: 261: 262: 263: 264: 265: 266: 267: 268: 269: 270: 271: 272: 273: 274: 275: 276: 277: 278: 279: 280: 281: 282: 283: 284: 285: 286: 287: 288: 289: 290: 291: 292: 293: 294: 295: 296: 297: 298: 299: 300: 301: 302: 303: 304: 305: 306: 307: 308: 309: 310: 311: 312: 313: 314: 315: 316: 317: 318: 319: 320: 321: 322: 323: 324: 325: 326: 327: 328: 329: 330: 331: 332: 333: 334: 335: 336: 337: 338: 339: 340: 341: 342: 343: 344: 345: 346: 347: 348: 349: 350: 351: 352: 353: 354: 355: 356: 357: 358: 359: 360: 361: 362: 363: 364: 365: 366: 367: 368: 369: 370: 

<?php
/**
 *
 * @package   Barcode Creator
 * @copyright (c) 2011 emberlabs.org
 * @license   http://opensource.org/licenses/mit-license.php The MIT License
 * @link      https://github.com/samt/barcode
 *
 * Minimum Requirement: PHP 5.3.0
 */
 
/**
 * Image_Barcode2_Driver_Ean13 class
 *
 * Renders EAN 13 barcodes
 *
 * PHP versions 5
 *
 * LICENSE: This source file is subject to version 3.0 of the PHP license
 * that is available through the world-wide-web at the following URI:
 * http://www.php.net/license/3_0.txt.  If you did not receive a copy of
 * the PHP License and are unable to obtain it through the web, please
 * send a note to license@php.net so we can mail you a copy immediately.
 *
 * @category  Image
 * @package   Image_Barcode2
 * @author    Didier Fournout <didier.fournout@nyc.fr>
 * @copyright 2005 The PHP Group
 * @license   http://www.php.net/license/3_0.txt  PHP License 3.0
 * @link      http://pear.php.net/package/Image_Barcode2
 */

namespace emberlabs\Barcode;

/**
 * emberlabs Barcode Creator - Ean13
 *           Generate Ean13 Barcodes
 *
 *
 * @license  http://opensource.org/licenses/mit-license.php The MIT License
 * @link        https://github.com/samt/barcode
 */
class Ean13 extends BarcodeBase
{
    /*
     * Coding map
     * @var array 
     */
    private $_codingmap = array(
        '0' => array(
            'A' => array(0,0,0,1,1,0,1),
            'B' => array(0,1,0,0,1,1,1),
            'C' => array(1,1,1,0,0,1,0)
        ),
        '1' => array(
            'A' => array(0,0,1,1,0,0,1),
            'B' => array(0,1,1,0,0,1,1),
            'C' => array(1,1,0,0,1,1,0)
        ),
        '2' => array(
            'A' => array(0,0,1,0,0,1,1),
            'B' => array(0,0,1,1,0,1,1),
            'C' => array(1,1,0,1,1,0,0)
        ),
        '3' => array(
            'A' => array(0,1,1,1,1,0,1),
            'B' => array(0,1,0,0,0,0,1),
            'C' => array(1,0,0,0,0,1,0)
        ),
        '4' => array(
            'A' => array(0,1,0,0,0,1,1),
            'B' => array(0,0,1,1,1,0,1),
            'C' => array(1,0,1,1,1,0,0)
        ),
        '5' => array(
            'A' => array(0,1,1,0,0,0,1),
            'B' => array(0,1,1,1,0,0,1),
            'C' => array(1,0,0,1,1,1,0)
        ),
        '6' => array(
            'A' => array(0,1,0,1,1,1,1),
            'B' => array(0,0,0,0,1,0,1),
            'C' => array(1,0,1,0,0,0,0)
        ),
        '7' => array(
            'A' => array(0,1,1,1,0,1,1),
            'B' => array(0,0,1,0,0,0,1),
            'C' => array(1,0,0,0,1,0,0)
        ),
        '8' => array(
            'A' => array(0,1,1,0,1,1,1),
            'B' => array(0,0,0,1,0,0,1),
            'C' => array(1,0,0,1,0,0,0)
        ),
        '9' => array(
            'A' => array(0,0,0,1,0,1,1),
            'B' => array(0,0,1,0,1,1,1),
            'C' => array(1,1,1,0,1,0,0)
        )
    );

    /*
     * Coding map left
     * @var array 
     */
    private $_codingmapleft = array(
        '0' => array('A','A','A','A','A','A'),
        '1' => array('A','A','B','A','B','B'),
        '2' => array('A','A','B','B','A','B'),
        '3' => array('A','A','B','B','B','A'),
        '4' => array('A','B','A','A','B','B'),
        '5' => array('A','B','B','A','A','B'),
        '6' => array('A','B','B','B','A','A'),
        '7' => array('A','B','A','B','A','B'),
        '8' => array('A','B','A','B','B','A'),
        '9' => array('A','B','B','A','B','A')
    );

    /*
     * Set the data
     *
     * @param mixed data - (int or string) Data to be encoded
     * @return instance of \emberlabs\Barcode\BarcodeInterface
     */
    public function setData($data)
    {
        $this->data = $data;
    }

    /*
     * Generate EAN13 code out of a provided number
     * Code taken from http://stackoverflow.com/questions/19890144/generate-valid-ean13-in-php (unknown copyright / license claims)
     *
     * @param number is the internal code you want to have EANed. The prefix, zero-padding and checksum are added by the function.
     * @return string with complete EAN13 code
     */
    public function generate($number)
    {
        $number = '200' . str_pad($number, 9, '0');
        $weightflag = true;
        $sum = 0;

        // Weight for a digit in the checksum is 3, 1, 3.. starting from the last digit.
        // loop backwards to make the loop length-agnostic. The same basic functionality
        // will work for codes of different lengths.
        for ($i = strlen($number) - 1; $i >= 0; --$i)
        {
            $sum += (int)$number[$i] * ($weightflag?3:1);
            $weightflag = !$weightflag;
        }
        $number .= (10 - ($sum % 10)) % 10;

        return $number;
    }

    public function validate($barcode)
    {
        // check to see if barcode is 13 digits long
        if (!preg_match("/^[0-9]{13}$/", $barcode)) {
            return false;
        }

        $digits = $barcode;

        // 1. Add the values of the digits in the
        // even-numbered positions: 2, 4, 6, etc.
        $even_sum = $digits[1] + $digits[3] + $digits[5] +
            $digits[7] + $digits[9] + $digits[11];

        // 2. Multiply this result by 3.
        $even_sum_three = $even_sum * 3;

        // 3. Add the values of the digits in the
        // odd-numbered positions: 1, 3, 5, etc.
        $odd_sum = $digits[0] + $digits[2] + $digits[4] +
            $digits[6] + $digits[8] + $digits[10];

        // 4. Sum the results of steps 2 and 3.
        $total_sum = $even_sum_three + $odd_sum;

        // 5. The check character is the smallest number which,
        // when added to the result in step 4, produces a multiple of 10.
        $next_ten = (ceil($total_sum / 10)) * 10;
        $check_digit = $next_ten - $total_sum;

        // if the check digit and the last digit of the
        // barcode are OK return true;
        if ($check_digit == $digits[12]) {
            return true;
        }

        return false;
    }

    /*
     * Draw the image
     *
     * @return void
     */
    public function draw()
    {
        // Bars is in reference to a single, 1-level bar
        $pxPerBar = 2;
        
        // Calculate the barcode width
        $barcodewidth = (strlen($this->data)) * (7 * $pxPerBar) 
            + 3 * $pxPerBar  // left
            + 5 * $pxPerBar  // center
            + 3 * $pxPerBar  // right
            ;

        $this->x = ($this->x == 0) ? $barcodewidth : $this->x;
            
        $this->img = @imagecreate($this->x, $this->y);
        
        if (!$this->img)
        {
            throw new \RuntimeException("Ean13: Image failed to initialize");
        }
        
        $white = imagecolorallocate($this->img, 255, 255, 255);
        $black = imagecolorallocate($this->img, 0, 0, 0);
        
        // Fill image with white color
        imagefill($this->img, 0, 0, $white);

        // get the first digit which is the key for creating the first 6 bars
        $key = substr($this->data, 0, 1);

        // Initiate x position centering the bar
        $xpos = ($this->x - $barcodewidth) / 2;
 
        // Draws the left guard pattern (bar-space-bar)
        // bar
        imagefilledrectangle(
            $this->img,
            $xpos,
            0,
            $xpos + $pxPerBar - 1,
            $this->y, 
            $black
        );

        $xpos += $pxPerBar;

        // space
        $xpos += $pxPerBar;

        // bar
        imagefilledrectangle(
            $this->img,
            $xpos,
            0,
            $xpos + $pxPerBar - 1,
            $this->y,
            $black
        );

        $xpos += $pxPerBar;

        // Draw left $this->data contents
        $set_array = $this->_codingmapleft[$key];

        for ($idx = 1; $idx < 7; ++$idx)
        {
            $value = substr($this->data, $idx, 1);

            foreach ($this->_codingmap[$value][$set_array[$idx - 1]] as $bar)
            {
                if ($bar)
                {
                    imagefilledrectangle(
                        $this->img,
                        $xpos,
                        0,
                        $xpos + $pxPerBar - 1,
                        $this->y,
                        $black
                    );
                }

                $xpos += $pxPerBar;
            }
        }

        // Draws the center pattern (space-bar-space-bar-space)
        // space
        $xpos += $pxPerBar;

        // bar
        imagefilledrectangle(
            $this->img,
            $xpos,
            0,
            $xpos + $pxPerBar - 1,
            $this->y,
            $black
        );

        $xpos += $pxPerBar;

        // space
        $xpos += $pxPerBar;

        // bar
        imagefilledrectangle(
            $this->img,
            $xpos,
            0,
            $xpos + $pxPerBar - 1,
            $this->y,
            $black
        );

        $xpos += $pxPerBar;

        // space
        $xpos += $pxPerBar;

        // Draw right $this->data contents
        for ($idx = 7; $idx < 13; ++$idx)
        {
            $value = substr($this->data, $idx, 1);

            foreach ($this->_codingmap[$value]['C'] as $bar)
            {
                if ($bar)
                {
                    imagefilledrectangle(
                        $this->img,
                        $xpos,
                        0,
                        $xpos + $pxPerBar - 1,
                        $this->y,
                        $black
                    );
                }

                $xpos += $pxPerBar;
            }
        }

        // Draws the right guard pattern (bar-space-bar)
        // bar
        imagefilledrectangle(
            $this->img,
            $xpos,
            0,
            $xpos + $pxPerBar - 1,
            $this->y,
            $black
        );

        $xpos += $pxPerBar;

        // space
        $xpos += $pxPerBar;

        // bar
        imagefilledrectangle(
            $this->img,
            $xpos,
            0,
            $xpos + $pxPerBar - 1,
            $this->y,
            $black
        );
    }
}
?>