/home/kueuepay/public_html/vendor/ezyang/htmlpurifier/library/HTMLPurifier/Lexer.php
<?php

/**
 * Forgivingly lexes HTML (SGML-style) markup into tokens.
 *
 * A lexer parses a string of SGML-style markup and converts them into
 * corresponding tokens.  It doesn't check for well-formedness, although its
 * internal mechanism may make this automatic (such as the case of
 * HTMLPurifier_Lexer_DOMLex).  There are several implementations to choose
 * from.
 *
 * A lexer is HTML-oriented: it might work with XML, but it's not
 * recommended, as we adhere to a subset of the specification for optimization
 * reasons. This might change in the future. Also, most tokenizers are not
 * expected to handle DTDs or PIs.
 *
 * This class should not be directly instantiated, but you may use create() to
 * retrieve a default copy of the lexer.  Being a supertype, this class
 * does not actually define any implementation, but offers commonly used
 * convenience functions for subclasses.
 *
 * @note The unit tests will instantiate this class for testing purposes, as
 *       many of the utility functions require a class to be instantiated.
 *       This means that, even though this class is not runnable, it will
 *       not be declared abstract.
 *
 * @par
 *
 * @note
 * We use tokens rather than create a DOM representation because DOM would:
 *
 * @par
 *  -# Require more processing and memory to create,
 *  -# Is not streamable, and
 *  -# Has the entire document structure (html and body not needed).
 *
 * @par
 * However, DOM is helpful in that it makes it easy to move around nodes
 * without a lot of lookaheads to see when a tag is closed. This is a
 * limitation of the token system and some workarounds would be nice.
 */
class HTMLPurifier_Lexer
{

    /**
     * Whether or not this lexer implements line-number/column-number tracking.
     * If it does, set to true.
     */
    public $tracksLineNumbers = false;

    /**
     * @type HTMLPurifier_EntityParser
     */
    private $_entity_parser;

    // -- STATIC ----------------------------------------------------------

    /**
     * Retrieves or sets the default Lexer as a Prototype Factory.
     *
     * By default HTMLPurifier_Lexer_DOMLex will be returned. There are
     * a few exceptions involving special features that only DirectLex
     * implements.
     *
     * @note The behavior of this class has changed, rather than accepting
     *       a prototype object, it now accepts a configuration object.
     *       To specify your own prototype, set %Core.LexerImpl to it.
     *       This change in behavior de-singletonizes the lexer object.
     *
     * @param HTMLPurifier_Config $config
     * @return HTMLPurifier_Lexer
     * @throws HTMLPurifier_Exception
     */
    public static function create($config)
    {
        if (!($config instanceof HTMLPurifier_Config)) {
            $lexer = $config;
            trigger_error(
                "Passing a prototype to
                HTMLPurifier_Lexer::create() is deprecated, please instead
                use %Core.LexerImpl",
                E_USER_WARNING
            );
        } else {
            $lexer = $config->get('Core.LexerImpl');
        }

        $needs_tracking =
            $config->get('Core.MaintainLineNumbers') ||
            $config->get('Core.CollectErrors');

        $inst = null;
        if (is_object($lexer)) {
            $inst = $lexer;
        } else {
            if (is_null($lexer)) {
                do {
                    // auto-detection algorithm
                    if ($needs_tracking) {
                        $lexer = 'DirectLex';
                        break;
                    }

                    if (class_exists('DOMDocument') &&
                        method_exists('DOMDocument', 'loadHTML') &&
                        !extension_loaded('domxml')
                    ) {
                        // check for DOM support, because while it's part of the
                        // core, it can be disabled compile time. Also, the PECL
                        // domxml extension overrides the default DOM, and is evil
                        // and nasty and we shan't bother to support it
                        $lexer = 'DOMLex';
                    } else {
                        $lexer = 'DirectLex';
                    }
                } while (0);
            } // do..while so we can break

            // instantiate recognized string names
            switch ($lexer) {
                case 'DOMLex':
                    $inst = new HTMLPurifier_Lexer_DOMLex();
                    break;
                case 'DirectLex':
                    $inst = new HTMLPurifier_Lexer_DirectLex();
                    break;
                case 'PH5P':
                    $inst = new HTMLPurifier_Lexer_PH5P();
                    break;
                default:
                    throw new HTMLPurifier_Exception(
                        "Cannot instantiate unrecognized Lexer type " .
                        htmlspecialchars($lexer)
                    );
            }
        }

        if (!$inst) {
            throw new HTMLPurifier_Exception('No lexer was instantiated');
        }

        // once PHP DOM implements native line numbers, or we
        // hack out something using XSLT, remove this stipulation
        if ($needs_tracking && !$inst->tracksLineNumbers) {
            throw new HTMLPurifier_Exception(
                'Cannot use lexer that does not support line numbers with ' .
                'Core.MaintainLineNumbers or Core.CollectErrors (use DirectLex instead)'
            );
        }

        return $inst;

    }

    // -- CONVENIENCE MEMBERS ---------------------------------------------

    public function __construct()
    {
        $this->_entity_parser = new HTMLPurifier_EntityParser();
    }

    /**
     * Most common entity to raw value conversion table for special entities.
     * @type array
     */
    protected $_special_entity2str =
        array(
            '&quot;' => '"',
            '&amp;' => '&',
            '&lt;' => '<',
            '&gt;' => '>',
            '&#39;' => "'",
            '&#039;' => "'",
            '&#x27;' => "'"
        );

    public function parseText($string, $config) {
        return $this->parseData($string, false, $config);
    }

    public function parseAttr($string, $config) {
        return $this->parseData($string, true, $config);
    }

    /**
     * Parses special entities into the proper characters.
     *
     * This string will translate escaped versions of the special characters
     * into the correct ones.
     *
     * @param string $string String character data to be parsed.
     * @return string Parsed character data.
     */
    public function parseData($string, $is_attr, $config)
    {
        // following functions require at least one character
        if ($string === '') {
            return '';
        }

        // subtracts amps that cannot possibly be escaped
        $num_amp = substr_count($string, '&') - substr_count($string, '& ') -
            ($string[strlen($string) - 1] === '&' ? 1 : 0);

        if (!$num_amp) {
            return $string;
        } // abort if no entities
        $num_esc_amp = substr_count($string, '&amp;');
        $string = strtr($string, $this->_special_entity2str);

        // code duplication for sake of optimization, see above
        $num_amp_2 = substr_count($string, '&') - substr_count($string, '& ') -
            ($string[strlen($string) - 1] === '&' ? 1 : 0);

        if ($num_amp_2 <= $num_esc_amp) {
            return $string;
        }

        // hmm... now we have some uncommon entities. Use the callback.
        if ($config->get('Core.LegacyEntityDecoder')) {
            $string = $this->_entity_parser->substituteSpecialEntities($string);
        } else {
            if ($is_attr) {
                $string = $this->_entity_parser->substituteAttrEntities($string);
            } else {
                $string = $this->_entity_parser->substituteTextEntities($string);
            }
        }
        return $string;
    }

    /**
     * Lexes an HTML string into tokens.
     * @param $string String HTML.
     * @param HTMLPurifier_Config $config
     * @param HTMLPurifier_Context $context
     * @return HTMLPurifier_Token[] array representation of HTML.
     */
    public function tokenizeHTML($string, $config, $context)
    {
        trigger_error('Call to abstract class', E_USER_ERROR);
    }

    /**
     * Translates CDATA sections into regular sections (through escaping).
     * @param string $string HTML string to process.
     * @return string HTML with CDATA sections escaped.
     */
    protected static function escapeCDATA($string)
    {
        return preg_replace_callback(
            '/<!\[CDATA\[(.+?)\]\]>/s',
            array('HTMLPurifier_Lexer', 'CDATACallback'),
            $string
        );
    }

    /**
     * Special CDATA case that is especially convoluted for <script>
     * @param string $string HTML string to process.
     * @return string HTML with CDATA sections escaped.
     */
    protected static function escapeCommentedCDATA($string)
    {
        return preg_replace_callback(
            '#<!--//--><!\[CDATA\[//><!--(.+?)//--><!\]\]>#s',
            array('HTMLPurifier_Lexer', 'CDATACallback'),
            $string
        );
    }

    /**
     * Special Internet Explorer conditional comments should be removed.
     * @param string $string HTML string to process.
     * @return string HTML with conditional comments removed.
     */
    protected static function removeIEConditional($string)
    {
        return preg_replace(
            '#<!--\[if [^>]+\]>.*?<!\[endif\]-->#si', // probably should generalize for all strings
            '',
            $string
        );
    }

    /**
     * Callback function for escapeCDATA() that does the work.
     *
     * @warning Though this is public in order to let the callback happen,
     *          calling it directly is not recommended.
     * @param array $matches PCRE matches array, with index 0 the entire match
     *                  and 1 the inside of the CDATA section.
     * @return string Escaped internals of the CDATA section.
     */
    protected static function CDATACallback($matches)
    {
        // not exactly sure why the character set is needed, but whatever
        return htmlspecialchars($matches[1], ENT_COMPAT, 'UTF-8');
    }

    /**
     * Takes a piece of HTML and normalizes it by converting entities, fixing
     * encoding, extracting bits, and other good stuff.
     * @param string $html HTML.
     * @param HTMLPurifier_Config $config
     * @param HTMLPurifier_Context $context
     * @return string
     * @todo Consider making protected
     */
    public function normalize($html, $config, $context)
    {
        // normalize newlines to \n
        if ($config->get('Core.NormalizeNewlines')) {
            $html = str_replace("\r\n", "\n", (string)$html);
            $html = str_replace("\r", "\n", (string)$html);
        }

        if ($config->get('HTML.Trusted')) {
            // escape convoluted CDATA
            $html = $this->escapeCommentedCDATA($html);
        }

        // escape CDATA
        $html = $this->escapeCDATA($html);

        $html = $this->removeIEConditional($html);

        // extract body from document if applicable
        if ($config->get('Core.ConvertDocumentToFragment')) {
            $e = false;
            if ($config->get('Core.CollectErrors')) {
                $e =& $context->get('ErrorCollector');
            }
            $new_html = $this->extractBody($html);
            if ($e && $new_html != $html) {
                $e->send(E_WARNING, 'Lexer: Extracted body');
            }
            $html = $new_html;
        }

        // expand entities that aren't the big five
        if ($config->get('Core.LegacyEntityDecoder')) {
            $html = $this->_entity_parser->substituteNonSpecialEntities($html);
        }

        // clean into wellformed UTF-8 string for an SGML context: this has
        // to be done after entity expansion because the entities sometimes
        // represent non-SGML characters (horror, horror!)
        $html = HTMLPurifier_Encoder::cleanUTF8($html);

        // if processing instructions are to removed, remove them now
        if ($config->get('Core.RemoveProcessingInstructions')) {
            $html = preg_replace('#<\?.+?\?>#s', '', $html);
        }

        $hidden_elements = $config->get('Core.HiddenElements');
        if ($config->get('Core.AggressivelyRemoveScript') &&
            !($config->get('HTML.Trusted') || !$config->get('Core.RemoveScriptContents')
            || empty($hidden_elements["script"]))) {
            $html = preg_replace('#<script[^>]*>.*?</script>#i', '', $html);
        }

        return $html;
    }

    /**
     * Takes a string of HTML (fragment or document) and returns the content
     * @todo Consider making protected
     */
    public function extractBody($html)
    {
        $matches = array();
        $result = preg_match('|(.*?)<body[^>]*>(.*)</body>|is', $html, $matches);
        if ($result) {
            // Make sure it's not in a comment
            $comment_start = strrpos($matches[1], '<!--');
            $comment_end   = strrpos($matches[1], '-->');
            if ($comment_start === false ||
                ($comment_end !== false && $comment_end > $comment_start)) {
                return $matches[2];
            }
        }
        return $html;
    }
}

// vim: et sw=4 sts=4
About
top

About NFC Pay: Our Story and Mission

NFC Pay was founded with a vision to transform the way people handle transactions. Our journey is defined by a commitment to innovation, security, and convenience. We strive to deliver seamless, user-friendly payment solutions that make everyday transactions effortless and secure. Our mission is to empower you to pay with ease and confidence, anytime, anywhere.

  • Simplifying Payments, One Tap at a Time.
  • Reinventing Your Wallet for Modern Convenience.
  • Smart Payments for a Effortless Lifestyle.
  • Experience the Ease of Tap and Pay.
  • Innovative Solutions for Your Daily Transactions.

Frequently Asked Questions About NFC Pay

Here are answers to some common questions about NFC Pay. We aim to provide clear and concise information to help you understand how our platform works and how it can benefit you. If you have any further inquiries, please don’t hesitate to contact our support team.

faq-img

How do I register for NFC Pay?

Download the app and sign up using your email or phone number, then complete the verification process.

Is my payment information secure?

Yes, we use advanced encryption and security protocols to protect your payment details.

Can I add multiple cards to my NFC Pay wallet?

Absolutely, you can link multiple debit or credit cards to your wallet.

How do I transfer money to another user?

Go to the transfer section, select the recipient, enter the amount, and authorize the transfer.

What should I do if I forget my PIN?

Use the “Forgot PIN” feature in the app to reset it following the provided instructions.

How can I activate my merchant account?

Sign up for a merchant account through the app and follow the setup instructions to start accepting payments.

Can I track my payment status?

Yes, you can view and track your payment status in the account dashboard