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<?php
/*
 * PHP QR Code encoder
 *
 * QR Code specifications
 *
 * Based on libqrencode C library distributed under LGPL 2.1
 * Copyright (C) 2006, 2007, 2008, 2009 Kentaro Fukuchi <fukuchi@megaui.net>
 *
 * PHP QR Code is distributed under LGPL 3
 * Copyright (C) 2010 Dominik Dzienia <deltalab at poczta dot fm>
 *
 * The following data / specifications are taken from
 * "Two dimensional symbol -- QR-code -- Basic Specification" (JIS X0510:2004)
 *  or
 * "Automatic identification and data capture techniques -- 
 *  QR Code 2005 bar code symbology specification" (ISO/IEC 18004:2006)
 *
 * This library is free software; you can redistribute it and/or
 * modify it under the terms of the GNU Lesser General Public
 * License as published by the Free Software Foundation; either
 * version 3 of the License, or any later version.
 *
 * This library is distributed in the hope that it will be useful,
 * but WITHOUT ANY WARRANTY; without even the implied warranty of
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
 * Lesser General Public License for more details.
 *
 * You should have received a copy of the GNU Lesser General Public
 * License along with this library; if not, write to the Free Software
 * Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA
 */
 
    define('QRSPEC_VERSION_MAX', 40);
    define('QRSPEC_WIDTH_MAX',   177);

    define('QRCAP_WIDTH',        0);
    define('QRCAP_WORDS',        1);
    define('QRCAP_REMINDER',     2);
    define('QRCAP_EC',           3);

    class QRspec {
    
        public static $capacity = array(
            array(  0,    0, 0, array(   0,    0,    0,    0)),
            array( 21,   26, 0, array(   7,   10,   13,   17)), // 1
            array( 25,   44, 7, array(  10,   16,   22,   28)),
            array( 29,   70, 7, array(  15,   26,   36,   44)),
            array( 33,  100, 7, array(  20,   36,   52,   64)),
            array( 37,  134, 7, array(  26,   48,   72,   88)), // 5
            array( 41,  172, 7, array(  36,   64,   96,  112)),
            array( 45,  196, 0, array(  40,   72,  108,  130)),
            array( 49,  242, 0, array(  48,   88,  132,  156)),
            array( 53,  292, 0, array(  60,  110,  160,  192)),
            array( 57,  346, 0, array(  72,  130,  192,  224)), //10
            array( 61,  404, 0, array(  80,  150,  224,  264)),
            array( 65,  466, 0, array(  96,  176,  260,  308)),
            array( 69,  532, 0, array( 104,  198,  288,  352)),
            array( 73,  581, 3, array( 120,  216,  320,  384)),
            array( 77,  655, 3, array( 132,  240,  360,  432)), //15
            array( 81,  733, 3, array( 144,  280,  408,  480)),
            array( 85,  815, 3, array( 168,  308,  448,  532)),
            array( 89,  901, 3, array( 180,  338,  504,  588)),
            array( 93,  991, 3, array( 196,  364,  546,  650)),
            array( 97, 1085, 3, array( 224,  416,  600,  700)), //20
            array(101, 1156, 4, array( 224,  442,  644,  750)),
            array(105, 1258, 4, array( 252,  476,  690,  816)),
            array(109, 1364, 4, array( 270,  504,  750,  900)),
            array(113, 1474, 4, array( 300,  560,  810,  960)),
            array(117, 1588, 4, array( 312,  588,  870, 1050)), //25
            array(121, 1706, 4, array( 336,  644,  952, 1110)),
            array(125, 1828, 4, array( 360,  700, 1020, 1200)),
            array(129, 1921, 3, array( 390,  728, 1050, 1260)),
            array(133, 2051, 3, array( 420,  784, 1140, 1350)),
            array(137, 2185, 3, array( 450,  812, 1200, 1440)), //30
            array(141, 2323, 3, array( 480,  868, 1290, 1530)),
            array(145, 2465, 3, array( 510,  924, 1350, 1620)),
            array(149, 2611, 3, array( 540,  980, 1440, 1710)),
            array(153, 2761, 3, array( 570, 1036, 1530, 1800)),
            array(157, 2876, 0, array( 570, 1064, 1590, 1890)), //35
            array(161, 3034, 0, array( 600, 1120, 1680, 1980)),
            array(165, 3196, 0, array( 630, 1204, 1770, 2100)),
            array(169, 3362, 0, array( 660, 1260, 1860, 2220)),
            array(173, 3532, 0, array( 720, 1316, 1950, 2310)),
            array(177, 3706, 0, array( 750, 1372, 2040, 2430)) //40
        );
        
        //----------------------------------------------------------------------
        public static function getDataLength($version, $level)
        {
            return self::$capacity[$version][QRCAP_WORDS] - self::$capacity[$version][QRCAP_EC][$level];
        }
        
        //----------------------------------------------------------------------
        public static function getECCLength($version, $level)
        {
            return self::$capacity[$version][QRCAP_EC][$level];
        }
        
        //----------------------------------------------------------------------
        public static function getWidth($version)
        {
            return self::$capacity[$version][QRCAP_WIDTH];
        }
        
        //----------------------------------------------------------------------
        public static function getRemainder($version)
        {
            return self::$capacity[$version][QRCAP_REMINDER];
        }
        
        //----------------------------------------------------------------------
        public static function getMinimumVersion($size, $level)
        {

            for($i=1; $i<= QRSPEC_VERSION_MAX; $i++) {
                $words  = self::$capacity[$i][QRCAP_WORDS] - self::$capacity[$i][QRCAP_EC][$level];
                if($words >= $size) 
                    return $i;
            }

            return -1;
        }
    
        //######################################################################
        
        public static $lengthTableBits = array(
            array(10, 12, 14),
            array( 9, 11, 13),
            array( 8, 16, 16),
            array( 8, 10, 12)
        );
        
        //----------------------------------------------------------------------
        public static function lengthIndicator($mode, $version)
        {
            if ($mode == QR_MODE_STRUCTURE)
                return 0;
                
            if ($version <= 9) {
                $l = 0;
            } else if ($version <= 26) {
                $l = 1;
            } else {
                $l = 2;
            }

            return self::$lengthTableBits[$mode][$l];
        }
        
        //----------------------------------------------------------------------
        public static function maximumWords($mode, $version)
        {
            if($mode == QR_MODE_STRUCTURE) 
                return 3;
                
            if($version <= 9) {
                $l = 0;
            } else if($version <= 26) {
                $l = 1;
            } else {
                $l = 2;
            }

            $bits = self::$lengthTableBits[$mode][$l];
            $words = (1 << $bits) - 1;
            
            if($mode == QR_MODE_KANJI) {
                $words *= 2; // the number of bytes is required
            }

            return $words;
        }

        // Error correction code -----------------------------------------------
        // Table of the error correction code (Reed-Solomon block)
        // See Table 12-16 (pp.30-36), JIS X0510:2004.

        public static $eccTable = array(
            array(array( 0,  0), array( 0,  0), array( 0,  0), array( 0,  0)),
            array(array( 1,  0), array( 1,  0), array( 1,  0), array( 1,  0)), // 1
            array(array( 1,  0), array( 1,  0), array( 1,  0), array( 1,  0)),
            array(array( 1,  0), array( 1,  0), array( 2,  0), array( 2,  0)),
            array(array( 1,  0), array( 2,  0), array( 2,  0), array( 4,  0)),
            array(array( 1,  0), array( 2,  0), array( 2,  2), array( 2,  2)), // 5
            array(array( 2,  0), array( 4,  0), array( 4,  0), array( 4,  0)),
            array(array( 2,  0), array( 4,  0), array( 2,  4), array( 4,  1)),
            array(array( 2,  0), array( 2,  2), array( 4,  2), array( 4,  2)),
            array(array( 2,  0), array( 3,  2), array( 4,  4), array( 4,  4)),
            array(array( 2,  2), array( 4,  1), array( 6,  2), array( 6,  2)), //10
            array(array( 4,  0), array( 1,  4), array( 4,  4), array( 3,  8)),
            array(array( 2,  2), array( 6,  2), array( 4,  6), array( 7,  4)),
            array(array( 4,  0), array( 8,  1), array( 8,  4), array(12,  4)),
            array(array( 3,  1), array( 4,  5), array(11,  5), array(11,  5)),
            array(array( 5,  1), array( 5,  5), array( 5,  7), array(11,  7)), //15
            array(array( 5,  1), array( 7,  3), array(15,  2), array( 3, 13)),
            array(array( 1,  5), array(10,  1), array( 1, 15), array( 2, 17)),
            array(array( 5,  1), array( 9,  4), array(17,  1), array( 2, 19)),
            array(array( 3,  4), array( 3, 11), array(17,  4), array( 9, 16)),
            array(array( 3,  5), array( 3, 13), array(15,  5), array(15, 10)), //20
            array(array( 4,  4), array(17,  0), array(17,  6), array(19,  6)),
            array(array( 2,  7), array(17,  0), array( 7, 16), array(34,  0)),
            array(array( 4,  5), array( 4, 14), array(11, 14), array(16, 14)),
            array(array( 6,  4), array( 6, 14), array(11, 16), array(30,  2)),
            array(array( 8,  4), array( 8, 13), array( 7, 22), array(22, 13)), //25
            array(array(10,  2), array(19,  4), array(28,  6), array(33,  4)),
            array(array( 8,  4), array(22,  3), array( 8, 26), array(12, 28)),
            array(array( 3, 10), array( 3, 23), array( 4, 31), array(11, 31)),
            array(array( 7,  7), array(21,  7), array( 1, 37), array(19, 26)),
            array(array( 5, 10), array(19, 10), array(15, 25), array(23, 25)), //30
            array(array(13,  3), array( 2, 29), array(42,  1), array(23, 28)),
            array(array(17,  0), array(10, 23), array(10, 35), array(19, 35)),
            array(array(17,  1), array(14, 21), array(29, 19), array(11, 46)),
            array(array(13,  6), array(14, 23), array(44,  7), array(59,  1)),
            array(array(12,  7), array(12, 26), array(39, 14), array(22, 41)), //35
            array(array( 6, 14), array( 6, 34), array(46, 10), array( 2, 64)),
            array(array(17,  4), array(29, 14), array(49, 10), array(24, 46)),
            array(array( 4, 18), array(13, 32), array(48, 14), array(42, 32)),
            array(array(20,  4), array(40,  7), array(43, 22), array(10, 67)),
            array(array(19,  6), array(18, 31), array(34, 34), array(20, 61)),//40
        );                                                                       

        //----------------------------------------------------------------------
        // CACHEABLE!!!
        
        public static function getEccSpec($version, $level, array &$spec)
        {
            if (count($spec) < 5) {
                $spec = array(0,0,0,0,0);
            }

            $b1   = self::$eccTable[$version][$level][0];
            $b2   = self::$eccTable[$version][$level][1];
            $data = self::getDataLength($version, $level);
            $ecc  = self::getECCLength($version, $level);

            if($b2 == 0) {
                $spec[0] = $b1;
                $spec[1] = (int)($data / $b1);
                $spec[2] = (int)($ecc / $b1);
                $spec[3] = 0; 
                $spec[4] = 0;
            } else {
                $spec[0] = $b1;
                $spec[1] = (int)($data / ($b1 + $b2));
                $spec[2] = (int)($ecc  / ($b1 + $b2));
                $spec[3] = $b2;
                $spec[4] = $spec[1] + 1;
            }
        }

        // Alignment pattern ---------------------------------------------------

        // Positions of alignment patterns.
        // This array includes only the second and the third position of the 
        // alignment patterns. Rest of them can be calculated from the distance 
        // between them.
         
        // See Table 1 in Appendix E (pp.71) of JIS X0510:2004.
         
        public static $alignmentPattern = array(      
            array( 0,  0),
            array( 0,  0), array(18,  0), array(22,  0), array(26,  0), array(30,  0), // 1- 5
            array(34,  0), array(22, 38), array(24, 42), array(26, 46), array(28, 50), // 6-10
            array(30, 54), array(32, 58), array(34, 62), array(26, 46), array(26, 48), //11-15
            array(26, 50), array(30, 54), array(30, 56), array(30, 58), array(34, 62), //16-20
            array(28, 50), array(26, 50), array(30, 54), array(28, 54), array(32, 58), //21-25
            array(30, 58), array(34, 62), array(26, 50), array(30, 54), array(26, 52), //26-30
            array(30, 56), array(34, 60), array(30, 58), array(34, 62), array(30, 54), //31-35
            array(24, 50), array(28, 54), array(32, 58), array(26, 54), array(30, 58), //35-40
        );                                                                                  

        
        /** --------------------------------------------------------------------
         * Put an alignment marker.
         * @param frame
         * @param width
         * @param ox,oy center coordinate of the pattern
         */
        public static function putAlignmentMarker(array &$frame, $ox, $oy)
        {
            $finder = array(
                "\xa1\xa1\xa1\xa1\xa1",
                "\xa1\xa0\xa0\xa0\xa1",
                "\xa1\xa0\xa1\xa0\xa1",
                "\xa1\xa0\xa0\xa0\xa1",
                "\xa1\xa1\xa1\xa1\xa1"
            );                        
            
            $yStart = $oy-2;         
            $xStart = $ox-2;
            
            for($y=0; $y<5; $y++) {
                QRstr::set($frame, $xStart, $yStart+$y, $finder[$y]);
            }
        }

        //----------------------------------------------------------------------
        public static function putAlignmentPattern($version, &$frame, $width)
        {
            if($version < 2)
                return;

            $d = self::$alignmentPattern[$version][1] - self::$alignmentPattern[$version][0];
            if($d < 0) {
                $w = 2;
            } else {
                $w = (int)(($width - self::$alignmentPattern[$version][0]) / $d + 2);
            }

            if($w * $w - 3 == 1) {
                $x = self::$alignmentPattern[$version][0];
                $y = self::$alignmentPattern[$version][0];
                self::putAlignmentMarker($frame, $x, $y);
                return;
            }

            $cx = self::$alignmentPattern[$version][0];
            for($x=1; $x<$w - 1; $x++) {
                self::putAlignmentMarker($frame, 6, $cx);
                self::putAlignmentMarker($frame, $cx,  6);
                $cx += $d;
            }

            $cy = self::$alignmentPattern[$version][0];
            for($y=0; $y<$w-1; $y++) {
                $cx = self::$alignmentPattern[$version][0];
                for($x=0; $x<$w-1; $x++) {
                    self::putAlignmentMarker($frame, $cx, $cy);
                    $cx += $d;
                }
                $cy += $d;
            }
        }

        // Version information pattern -----------------------------------------

		// Version information pattern (BCH coded).
        // See Table 1 in Appendix D (pp.68) of JIS X0510:2004.
        
		// size: [QRSPEC_VERSION_MAX - 6]
		
        public static $versionPattern = array(
            0x07c94, 0x085bc, 0x09a99, 0x0a4d3, 0x0bbf6, 0x0c762, 0x0d847, 0x0e60d,
            0x0f928, 0x10b78, 0x1145d, 0x12a17, 0x13532, 0x149a6, 0x15683, 0x168c9,
            0x177ec, 0x18ec4, 0x191e1, 0x1afab, 0x1b08e, 0x1cc1a, 0x1d33f, 0x1ed75,
            0x1f250, 0x209d5, 0x216f0, 0x228ba, 0x2379f, 0x24b0b, 0x2542e, 0x26a64,
            0x27541, 0x28c69
        );

        //----------------------------------------------------------------------
        public static function getVersionPattern($version)
        {
            if($version < 7 || $version > QRSPEC_VERSION_MAX)
                return 0;

            return self::$versionPattern[$version -7];
        }

        // Format information --------------------------------------------------
        // See calcFormatInfo in tests/test_qrspec.c (orginal qrencode c lib)
        
        public static $formatInfo = array(
            array(0x77c4, 0x72f3, 0x7daa, 0x789d, 0x662f, 0x6318, 0x6c41, 0x6976),
            array(0x5412, 0x5125, 0x5e7c, 0x5b4b, 0x45f9, 0x40ce, 0x4f97, 0x4aa0),
            array(0x355f, 0x3068, 0x3f31, 0x3a06, 0x24b4, 0x2183, 0x2eda, 0x2bed),
            array(0x1689, 0x13be, 0x1ce7, 0x19d0, 0x0762, 0x0255, 0x0d0c, 0x083b)
        );

        public static function getFormatInfo($mask, $level)
        {
            if($mask < 0 || $mask > 7)
                return 0;
                
            if($level < 0 || $level > 3)
                return 0;                

            return self::$formatInfo[$level][$mask];
        }

        // Frame ---------------------------------------------------------------
        // Cache of initial frames.
         
        public static $frames = array();

        /** --------------------------------------------------------------------
         * Put a finder pattern.
         * @param frame
         * @param width
         * @param ox,oy upper-left coordinate of the pattern
         */
        public static function putFinderPattern(&$frame, $ox, $oy)
        {
            $finder = array(
                "\xc1\xc1\xc1\xc1\xc1\xc1\xc1",
                "\xc1\xc0\xc0\xc0\xc0\xc0\xc1",
                "\xc1\xc0\xc1\xc1\xc1\xc0\xc1",
                "\xc1\xc0\xc1\xc1\xc1\xc0\xc1",
                "\xc1\xc0\xc1\xc1\xc1\xc0\xc1",
                "\xc1\xc0\xc0\xc0\xc0\xc0\xc1",
                "\xc1\xc1\xc1\xc1\xc1\xc1\xc1"
            );                            
            
            for($y=0; $y<7; $y++) {
                QRstr::set($frame, $ox, $oy+$y, $finder[$y]);
            }
        }

        //----------------------------------------------------------------------
        public static function createFrame($version)
        {
            $width = self::$capacity[$version][QRCAP_WIDTH];
            $frameLine = str_repeat ("\0", $width);
            $frame = array_fill(0, $width, $frameLine);

            // Finder pattern
            self::putFinderPattern($frame, 0, 0);
            self::putFinderPattern($frame, $width - 7, 0);
            self::putFinderPattern($frame, 0, $width - 7);
            
            // Separator
            $yOffset = $width - 7;
            
            for($y=0; $y<7; $y++) {
                $frame[$y][7] = "\xc0";
                $frame[$y][$width - 8] = "\xc0";
                $frame[$yOffset][7] = "\xc0";
                $yOffset++;
            }
            
            $setPattern = str_repeat("\xc0", 8);
            
            QRstr::set($frame, 0, 7, $setPattern);
            QRstr::set($frame, $width-8, 7, $setPattern);
            QRstr::set($frame, 0, $width - 8, $setPattern);
        
            // Format info
            $setPattern = str_repeat("\x84", 9);
            QRstr::set($frame, 0, 8, $setPattern);
            QRstr::set($frame, $width - 8, 8, $setPattern, 8);
            
            $yOffset = $width - 8;

            for($y=0; $y<8; $y++,$yOffset++) {
                $frame[$y][8] = "\x84";
                $frame[$yOffset][8] = "\x84";
            }

            // Timing pattern  
            
            for($i=1; $i<$width-15; $i++) {
                $frame[6][7+$i] = chr(0x90 | ($i & 1));
                $frame[7+$i][6] = chr(0x90 | ($i & 1));
            }
            
            // Alignment pattern  
            self::putAlignmentPattern($version, $frame, $width);
            
            // Version information 
            if($version >= 7) {
                $vinf = self::getVersionPattern($version);

                $v = $vinf;
                
                for($x=0; $x<6; $x++) {
                    for($y=0; $y<3; $y++) {
                        $frame[($width - 11)+$y][$x] = chr(0x88 | ($v & 1));
                        $v = $v >> 1;
                    }
                }

                $v = $vinf;
                for($y=0; $y<6; $y++) {
                    for($x=0; $x<3; $x++) {
                        $frame[$y][$x+($width - 11)] = chr(0x88 | ($v & 1));
                        $v = $v >> 1;
                    }
                }
            }
    
            // and a little bit...  
            $frame[$width - 8][8] = "\x81";
            
            return $frame;
        }

        //----------------------------------------------------------------------
        public static function debug($frame, $binary_mode = false)
        {
            if ($binary_mode) {
            
                    foreach ($frame as &$frameLine) {
                        $frameLine = join('<span class="m">&nbsp;&nbsp;</span>', explode('0', $frameLine));
                        $frameLine = join('&#9608;&#9608;', explode('1', $frameLine));
                    }
                    
                    ?>
                <style>
                    .m { background-color: white; }
                </style>
                <?php
                    echo '<pre><tt><br/ ><br/ ><br/ >&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;';
                    echo join("<br/ >&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;", $frame);
                    echo '</tt></pre><br/ ><br/ ><br/ ><br/ ><br/ ><br/ >';
            
            } else {
            
                foreach ($frame as &$frameLine) {
                    $frameLine = join('<span class="m">&nbsp;</span>',  explode("\xc0", $frameLine));
                    $frameLine = join('<span class="m">&#9618;</span>', explode("\xc1", $frameLine));
                    $frameLine = join('<span class="p">&nbsp;</span>',  explode("\xa0", $frameLine));
                    $frameLine = join('<span class="p">&#9618;</span>', explode("\xa1", $frameLine));
                    $frameLine = join('<span class="s">&#9671;</span>', explode("\x84", $frameLine)); //format 0
                    $frameLine = join('<span class="s">&#9670;</span>', explode("\x85", $frameLine)); //format 1
                    $frameLine = join('<span class="x">&#9762;</span>', explode("\x81", $frameLine)); //special bit
                    $frameLine = join('<span class="c">&nbsp;</span>',  explode("\x90", $frameLine)); //clock 0
                    $frameLine = join('<span class="c">&#9719;</span>', explode("\x91", $frameLine)); //clock 1
                    $frameLine = join('<span class="f">&nbsp;</span>',  explode("\x88", $frameLine)); //version
                    $frameLine = join('<span class="f">&#9618;</span>', explode("\x89", $frameLine)); //version
                    $frameLine = join('&#9830;', explode("\x01", $frameLine));
                    $frameLine = join('&#8901;', explode("\0", $frameLine));
                }
                
                ?>
                <style>
                    .p { background-color: yellow; }
                    .m { background-color: #00FF00; }
                    .s { background-color: #FF0000; }
                    .c { background-color: aqua; }
                    .x { background-color: pink; }
                    .f { background-color: gold; }
                </style>
                <?php
                echo "<pre><tt>";
                echo join("<br/ >", $frame);
                echo "</tt></pre>";
            
            }
        }

        //----------------------------------------------------------------------
        public static function serial($frame)
        {
            return gzcompress(join("\n", $frame), 9);
        }
        
        //----------------------------------------------------------------------
        public static function unserial($code)
        {
            return explode("\n", gzuncompress($code));
        }
        
        //----------------------------------------------------------------------
        public static function newFrame($version)
        {
            if($version < 1 || $version > QRSPEC_VERSION_MAX) 
                return null;

            if(!isset(self::$frames[$version])) {
                
                $fileName = QR_CACHE_DIR.'frame_'.$version.'.dat';
                
                if (QR_CACHEABLE) {
                    if (file_exists($fileName)) {
                        self::$frames[$version] = self::unserial(file_get_contents($fileName));
                    } else {
                        self::$frames[$version] = self::createFrame($version);
                        file_put_contents($fileName, self::serial(self::$frames[$version]));
                    }
                } else {
                    self::$frames[$version] = self::createFrame($version);
                }
            }
            
            if(is_null(self::$frames[$version]))
                return null;

            return self::$frames[$version];
        }

        //----------------------------------------------------------------------
        public static function rsBlockNum($spec)     { return $spec[0] + $spec[3]; }
        public static function rsBlockNum1($spec)    { return $spec[0]; }
        public static function rsDataCodes1($spec)   { return $spec[1]; }
        public static function rsEccCodes1($spec)    { return $spec[2]; }
        public static function rsBlockNum2($spec)    { return $spec[3]; }
        public static function rsDataCodes2($spec)   { return $spec[4]; }
        public static function rsEccCodes2($spec)    { return $spec[2]; }
        public static function rsDataLength($spec)   { return ($spec[0] * $spec[1]) + ($spec[3] * $spec[4]);    }
        public static function rsEccLength($spec)    { return ($spec[0] + $spec[3]) * $spec[2]; }
        
    }