<?php
/**
 * @copyright 2008-2010 addedbytes.com
 * @copyright 2016 Vanilla Forums Inc. (changes only)
 * @license BSDv2
 */

namespace Nbbc;

/**
 * A class to validate email address strings.
 *
 * The EmailAddressValidator Class originally from http://code.google.com/p/php-email-address-validation/.
 * It's released under New BSD license: http://www.opensource.org/licenses/bsd-license.php.
 *
 * Sample Code
 *
 * ```
 * $validator = new EmailAddressValidator;
 * if ($validator->check_email_address('test@example.org')) {
 *     // Email address is technically valid
 * }
 * ```
 *
 * @deprecated
 */
class EmailAddressValidator {
    // Check email address validity.
    // @param   strEmailAddress     Email address to be checked
    // @return  True if email is valid, false if not
    function check_email_address($strEmailAddress) {

        // If magic quotes is "on", email addresses with quote marks will
        // fail validation because of added escape characters. Uncommenting
        // the next three lines will allow for this issue.
        //if (get_magic_quotes_gpc()) {
        //    $strEmailAddress = stripslashes($strEmailAddress);
        //}

        // Control characters are not allowed
        if (preg_match('/[\x00-\x1F\x7F-\xFF]/', $strEmailAddress)) {
            return false;
        }

        // Split it into sections using last instance of "@"
        $intAtSymbol = strrpos($strEmailAddress, '@');
        if ($intAtSymbol === false) {
            // No "@" symbol in email.
            return false;
        }
        $arrEmailAddress[0] = substr($strEmailAddress, 0, $intAtSymbol);
        $arrEmailAddress[1] = substr($strEmailAddress, $intAtSymbol + 1);

        // Count the "@" symbols. Only one is allowed, except where
        // contained in quote marks in the local part. Quickest way to
        // check this is to remove anything in quotes.
        $arrTempAddress[0] = preg_replace('/"[^"]+"/', '', $arrEmailAddress[0]);
        $arrTempAddress[1] = $arrEmailAddress[1];
        $strTempAddress = $arrTempAddress[0] . $arrTempAddress[1];
        // Then check - should be no "@" symbols.
        if (strrpos($strTempAddress, '@') !== false) {
            // "@" symbol found
            return false;
        }

        // Check local portion
        if (!$this->check_local_portion($arrEmailAddress[0])) {
            return false;
        }

        // Check domain portion
        if (!$this->check_domain_portion($arrEmailAddress[1])) {
            return false;
        }

        // If we're still here, all checks above passed. Email is valid.
        return true;

    }

    // Checks email section before "@" symbol for validity
    // @param   strLocalPortion     Text to be checked
    // @return  True if local portion is valid, false if not
    function check_local_portion($strLocalPortion) {
        // Local portion can only be from 1 to 64 characters, inclusive.
        // Please note that servers are encouraged to accept longer local
        // parts than 64 characters.
        if (!$this->check_text_length($strLocalPortion, 1, 64)) {
            return false;
        }
        // Local portion must be:
        // 1) a dot-atom (strings separated by periods)
        // 2) a quoted string
        // 3) an obsolete format string (combination of the above)
        $arrLocalPortion = explode('.', $strLocalPortion);
        for ($i = 0, $max = \count($arrLocalPortion); $i < $max; $i++) {
            if (!preg_match('.^('
                . '([A-Za-z0-9!#$%&\'*+/=?^_`{|}~-]'
                . '[A-Za-z0-9!#$%&\'*+/=?^_`{|}~-]{0,63})'
                . '|'
                . '("[^\\\"]{0,62}")'
                . ')$.', $arrLocalPortion[$i])
            ) {
                return false;
            }
        }

        return true;
    }

    // Checks email section after "@" symbol for validity
    // @param   strDomainPortion     Text to be checked
    // @return  True if domain portion is valid, false if not
    function check_domain_portion($strDomainPortion) {
        // Total domain can only be from 1 to 255 characters, inclusive
        if (!$this->check_text_length($strDomainPortion, 1, 255)) {
            return false;
        }
        // Check if domain is IP, possibly enclosed in square brackets.
        if (preg_match('/^(25[0-5]|2[0-4][0-9]|1[0-9][0-9]|[1-9]?[0-9])'
                . '(\.(25[0-5]|2[0-4][0-9]|1[0-9][0-9]|[1-9]?[0-9])){3}$/', $strDomainPortion) ||
            preg_match('/^\[(25[0-5]|2[0-4][0-9]|1[0-9][0-9]|[1-9]?[0-9])'
                . '(\.(25[0-5]|2[0-4][0-9]|1[0-9][0-9]|[1-9]?[0-9])){3}\]$/', $strDomainPortion)
        ) {
            return true;
        } else {
            $arrDomainPortion = explode('.', $strDomainPortion);
            if (\count($arrDomainPortion) < 2) {
                return false; // Not enough parts to domain
            }
            for ($i = 0, $max = \count($arrDomainPortion); $i < $max; $i++) {
                // Each portion must be between 1 and 63 characters, inclusive
                if (!$this->check_text_length($arrDomainPortion[$i], 1, 63)) {
                    return false;
                }
                if (!preg_match('/^(([A-Za-z0-9][A-Za-z0-9-]{0,61}[A-Za-z0-9])|'
                    . '([A-Za-z0-9]+))$/', $arrDomainPortion[$i])
                ) {
                    return false;
                }
            }
        }

        return true;
    }

    // Check given text length is between defined bounds
    // @param   strText     Text to be checked
    // @param   intMinimum  Minimum acceptable length
    // @param   intMaximum  Maximum acceptable length
    // @return  True if string is within bounds (inclusive), false if not
    function check_text_length($strText, $intMinimum, $intMaximum) {
        // Minimum and maximum are both inclusive
        $intTextLength = \strlen($strText);
        if (($intTextLength < $intMinimum) || ($intTextLength > $intMaximum)) {
            return false;
        } else {
            return true;
        }
    }

}