<?php

/**
 * Class AlphaNum
 *
 * @created      25.11.2015
 * @author       Smiley <smiley@chillerlan.net>
 * @copyright    2015 Smiley
 * @license      MIT
 */
namespace WCPOS\Vendor\chillerlan\QRCode\Data;

use WCPOS\Vendor\chillerlan\QRCode\Common\BitBuffer;
use WCPOS\Vendor\chillerlan\QRCode\Common\Mode;
use function ceil, intdiv, preg_match, strpos;
/**
 * Alphanumeric mode: 0 to 9, A to Z, space, $ % * + - . / :
 *
 * ISO/IEC 18004:2000 Section 8.3.3
 * ISO/IEC 18004:2000 Section 8.4.3
 */
final class AlphaNum extends QRDataModeAbstract
{
    /**
     * ISO/IEC 18004:2000 Table 5
     *
     * @var string
     */
    private const CHAR_MAP = '0123456789ABCDEFGHIJKLMNOPQRSTUVWXYZ $%*+-./:';
    /**
     * @inheritDoc
     */
    public const DATAMODE = Mode::ALPHANUM;
    /**
     * @inheritDoc
     */
    public function getLengthInBits() : int
    {
        return (int) ceil($this->getCharCount() * (11 / 2));
    }
    /**
     * @inheritDoc
     */
    public static function validateString(string $string) : bool
    {
        return (bool) preg_match('/^[A-Z\\d %$*+\\-.:\\/]+$/', $string);
    }
    /**
     * @inheritDoc
     */
    public function write(BitBuffer $bitBuffer, int $versionNumber) : QRDataModeInterface
    {
        $len = $this->getCharCount();
        $bitBuffer->put(self::DATAMODE, 4)->put($len, $this::getLengthBits($versionNumber));
        // encode 2 characters in 11 bits
        for ($i = 0; $i + 1 < $len; $i += 2) {
            $bitBuffer->put($this->ord($this->data[$i]) * 45 + $this->ord($this->data[$i + 1]), 11);
        }
        // encode a remaining character in 6 bits
        if ($i < $len) {
            $bitBuffer->put($this->ord($this->data[$i]), 6);
        }
        return $this;
    }
    /**
     * @inheritDoc
     *
     * @throws \chillerlan\QRCode\Data\QRCodeDataException
     */
    public static function decodeSegment(BitBuffer $bitBuffer, int $versionNumber) : string
    {
        $length = $bitBuffer->read(self::getLengthBits($versionNumber));
        $result = '';
        // Read two characters at a time
        while ($length > 1) {
            if ($bitBuffer->available() < 11) {
                throw new QRCodeDataException('not enough bits available');
                // @codeCoverageIgnore
            }
            $nextTwoCharsBits = $bitBuffer->read(11);
            $result .= self::chr(intdiv($nextTwoCharsBits, 45));
            $result .= self::chr($nextTwoCharsBits % 45);
            $length -= 2;
        }
        if ($length === 1) {
            // special case: one character left
            if ($bitBuffer->available() < 6) {
                throw new QRCodeDataException('not enough bits available');
                // @codeCoverageIgnore
            }
            $result .= self::chr($bitBuffer->read(6));
        }
        return $result;
    }
    /**
     * @throws \chillerlan\QRCode\Data\QRCodeDataException
     */
    private function ord(string $chr) : int
    {
        /** @phan-suppress-next-line PhanParamSuspiciousOrder */
        $ord = strpos(self::CHAR_MAP, $chr);
        if ($ord === \false) {
            throw new QRCodeDataException('invalid character');
            // @codeCoverageIgnore
        }
        return $ord;
    }
    /**
     * @throws \chillerlan\QRCode\Data\QRCodeDataException
     */
    private static function chr(int $ord) : string
    {
        if ($ord < 0 || $ord > 44) {
            throw new QRCodeDataException('invalid character code');
            // @codeCoverageIgnore
        }
        return self::CHAR_MAP[$ord];
    }
}