/home/kueuepay/public_html/vendor/ezyang/htmlpurifier/library/HTMLPurifier/AttrDef/CSS/Number.php
<?php

/**
 * Validates a number as defined by the CSS spec.
 */
class HTMLPurifier_AttrDef_CSS_Number extends HTMLPurifier_AttrDef
{

    /**
     * Indicates whether or not only positive values are allowed.
     * @type bool
     */
    protected $non_negative = false;

    /**
     * @param bool $non_negative indicates whether negatives are forbidden
     */
    public function __construct($non_negative = false)
    {
        $this->non_negative = $non_negative;
    }

    /**
     * @param string $number
     * @param HTMLPurifier_Config $config
     * @param HTMLPurifier_Context $context
     * @return string|bool
     * @warning Some contexts do not pass $config, $context. These
     *          variables should not be used without checking HTMLPurifier_Length
     */
    public function validate($number, $config, $context)
    {
        $number = $this->parseCDATA($number);

        if ($number === '') {
            return false;
        }
        if ($number === '0') {
            return '0';
        }

        $sign = '';
        switch ($number[0]) {
            case '-':
                if ($this->non_negative) {
                    return false;
                }
                $sign = '-';
            case '+':
                $number = substr($number, 1);
        }

        if (ctype_digit($number)) {
            $number = ltrim($number, '0');
            return $number ? $sign . $number : '0';
        }

        // Period is the only non-numeric character allowed
        if (strpos($number, '.') === false) {
            return false;
        }

        list($left, $right) = explode('.', $number, 2);

        if ($left === '' && $right === '') {
            return false;
        }
        if ($left !== '' && !ctype_digit($left)) {
            return false;
        }

        // Remove leading zeros until positive number or a zero stays left
        if (ltrim($left, '0') != '') {
            $left = ltrim($left, '0');
        } else {
            $left = '0';
        }

        $right = rtrim($right, '0');

        if ($right === '') {
            return $left ? $sign . $left : '0';
        } elseif (!ctype_digit($right)) {
            return false;
        }
        return $sign . $left . '.' . $right;
    }
}

// vim: et sw=4 sts=4
Best Practice

Best Practices

To ensure a smooth integration process and optimal performance, follow these best practices:

  1. Use secure HTTPS connections for all API requests.
  2. Implement robust error handling to handle potential issues gracefully.
  3. Regularly update your integration to stay current with any API changes or enhancements.