<?php

/**
 * 验证类
 *
 * @author     呼吸二氧化碳 <jonwang@myqee.com>
 * @category   MyQEE
 * @package    System
 * @subpackage Core
 * @copyright  Copyright (c) 2008-2013 myqee.com
 * @license    http://www.myqee.com/license.html
 */
class Core_Valid
{

    /**
     * Checks if a field is not empty.
     *
     * @return  boolean
     */
    public static function not_empty($value)
    {
        if (is_object($value) && $value instanceof ArrayObject)
        {
            // Get the array from the ArrayObject
            $value = $value->getArrayCopy();
        }

        // Value cannot be NULL, false, '', or an empty array
        return !in_array($value, array(null, false, '', array()), true);
    }

    /**
     * Checks a field against a regular expression.
     *
     * @param   string  value
     * @param   string  regular expression to match (including delimiters)
     * @return  boolean
     */
    public static function regex($value, $expression)
    {
        return (bool)preg_match($expression, (string)$value);
    }

    /**
     * Checks that a field is long enough.
     *
     * @param   string   value
     * @param   integer  minimum length required
     * @return  boolean
     */
    public static function min_length($value, $length)
    {
        return UTF8::strlen($value) >= $length;
    }

    /**
     * Checks that a field is short enough.
     *
     * @param   string   value
     * @param   integer  maximum length required
     * @return  boolean
     */
    public static function max_length($value, $length)
    {
        return UTF8::strlen($value) <= $length;
    }

    /**
     * Checks that a field is exactly the right length.
     *
     * @param   string   value
     * @param   integer  exact length required
     * @return  boolean
     */
    public static function exact_length($value, $length)
    {
        return UTF8::strlen($value) === $length;
    }

    /**
     * Checks that a field is exactly the value required.
     *
     * @param   string   value
     * @param   string   required value
     * @return  boolean
     */
    public static function equals($value, $required)
    {
        return ($value === $required);
    }

    /**
     * Check an email address for correct format.
     *
     * @link  http://www.iamcal.com/publish/articles/php/parsing_email/
     * @link  http://www.w3.org/Protocols/rfc822/
     *
     * @param   string   email address
     * @param   boolean  strict RFC compatibility
     * @return  boolean
     */
    public static function email($email, $strict = false)
    {
        if ($strict === true)
        {
            $qtext = '[^\\x0d\\x22\\x5c\\x80-\\xff]';
            $dtext = '[^\\x0d\\x5b-\\x5d\\x80-\\xff]';
            $atom  = '[^\\x00-\\x20\\x22\\x28\\x29\\x2c\\x2e\\x3a-\\x3c\\x3e\\x40\\x5b-\\x5d\\x7f-\\xff]+';
            $pair  = '\\x5c[\\x00-\\x7f]';

            $domain_literal = "\\x5b($dtext|$pair)*\\x5d";
            $quoted_string  = "\\x22($qtext|$pair)*\\x22";
            $sub_domain     = "($atom|$domain_literal)";
            $word           = "($atom|$quoted_string)";
            $domain         = "$sub_domain(\\x2e$sub_domain)*";
            $local_part     = "$word(\\x2e$word)*";

            $expression     = "/^$local_part\\x40$domain$/D";
        }
        else
        {
            $expression = '/^[-_a-z0-9\'+*$^&%=~!?{}]++(?:\.[-_a-z0-9\'+*$^&%=~!?{}]+)*+@(?:(?![-.])[-a-z0-9.]+(?<![-.])\.[a-z]{2,6}|\d{1,3}(?:\.\d{1,3}){3})(?::\d++)?$/iD';
        }

        return (bool)preg_match($expression, (string)$email);
    }

    /**
     * Validate the domain of an email address by checking if the domain has a
     * valid MX record.
     *
     * @link  http://php.net/checkdnsrr  not added to Windows until PHP 5.3.0
     *
     * @param   string   email address
     * @return  boolean
     */
    public static function email_domain($email)
    {
        // Check if the email domain has a valid MX record
        return (bool)checkdnsrr(preg_replace('/^[^@]++@/', '', $email), 'MX');
    }

    /**
     * Validate a URL.
     *
     * @param   string   URL
     * @return  boolean
     */
    public static function url($url)
    {
        // Based on http://www.apps.ietf.org/rfc/rfc1738.html#sec-5
        if ( !preg_match(
        	'~^

            # scheme
            [-a-z0-9+.]++://

            # username:password (optional)
            (?:
                    [-a-z0-9$_.+!*\'(),;?&=%]++   # username
                (?::[-a-z0-9$_.+!*\'(),;?&=%]++)? # password (optional)
                @
            )?

            (?:
                # ip address
                \d{1,3}+(?:\.\d{1,3}+){3}+

                | # or

                # hostname (captured)
                (
                         (?!-)[-a-z0-9]{1,63}+(?<!-)
                    (?:\.(?!-)[-a-z0-9]{1,63}+(?<!-)){0,126}+
                )
            )

            # port (optional)
            (?::\d{1,5}+)?

            # path (optional)
            (?:/.*)?

            $~iDx', $url, $matches) ) return false;

        // We matched an IP address
        if ( !isset($matches[1]) ) return true;

        // Check maximum length of the whole hostname
        // http://en.wikipedia.org/wiki/Domain_name#cite_note-0
        if (strlen($matches[1]) > 253) return false;

        // An extra check for the top level domain
        // It must start with a letter
        $tld = ltrim(substr($matches[1], (int)strrpos($matches[1], '.')), '.');

        return ctype_alpha($tld[0]);
    }

    /**
     * Validate an IP.
     *
     * @param   string   IP address
     * @param   boolean  allow private IP networks
     * @return  boolean
     */
    public static function ip($ip, $allow_private = true)
    {
        // Do not allow reserved addresses
        $flags = FILTER_FLAG_NO_RES_RANGE;

        if ( $allow_private === false )
        {
            // Do not allow private or reserved addresses
            $flags = $flags | FILTER_FLAG_NO_PRIV_RANGE;
        }

        return (bool)filter_var($ip, FILTER_VALIDATE_IP, $flags);
    }

    /**
     * Validates a credit card number, with a Luhn check if possible.
     *
     * @param   integer       credit card number
     * @param   string|array  card type, or an array of card types
     * @return  boolean
     * @uses    Validate::luhn
     */
    public static function credit_card($number, $type = null)
    {
        // Remove all non-digit characters from the number
        if ( ($number = preg_replace('/\D+/', '', $number)) === '' ) return false;

        if ($type == null)
        {
            // Use the default type
            $type = 'default';
        }
        elseif (is_array($type))
        {
            foreach ($type as $t)
            {
                // Test each type for validity
                if (Valid::credit_card($number, $t)) return true;
            }

            return false;
        }

        $cards = Core::config('credit_cards');

        // Check card type
        $type = strtolower($type);

        if (!isset($cards[$type])) return false;

        // Check card number length
        $length = strlen($number);

        // Validate the card length by the card type
        if (!in_array($length, preg_split('/\D+/', $cards[$type]['length']))) return false;

        // Check card number prefix
        if (!preg_match('/^' . $cards[$type]['prefix'] . '/', $number)) return false;

        // No Luhn check required
        if ($cards[$type]['luhn'] == false) return true;

        return Valid::luhn($number);
    }

    /**
     * Validate a number against the [Luhn](http://en.wikipedia.org/wiki/Luhn_algorithm)
     * (mod10) formula.
     *
     * @param   string   number to check
     * @return  boolean
     */
    public static function luhn($number)
    {
        // Force the value to be a string as this method uses string functions.
        // Converting to an integer may pass PHP_INT_MAX and result in an error!
        $number = (string)$number;

        if (!ctype_digit($number))
        {
            // Luhn can only be used on numbers!
            return false;
        }

        // Check number length
        $length = strlen($number);

        // Checksum of the card number
        $checksum = 0;

        for($i = $length - 1; $i >= 0; $i -= 2)
        {
            // Add up every 2nd digit, starting from the right
            $checksum += substr($number, $i, 1);
        }

        for($i = $length - 2; $i >= 0; $i -= 2)
        {
            // Add up every 2nd digit doubled, starting from the right
            $double = substr($number, $i, 1) * 2;

            // Subtract 9 from the double where value is greater than 10
            $checksum += ($double >= 10) ? ($double - 9) : $double;
        }

        // If the checksum is a multiple of 10, the number is valid
        return ($checksum % 10 === 0);
    }

    /**
     * Tests if a string is a valid date string.
     *
     * @param   string   date to check
     * @return  boolean
     */
    public static function date($str)
    {
        return (strtotime($str) !== false);
    }

    /**
     * Checks whether a string consists of alphabetical characters only.
     *
     * @param   string   input string
     * @param   boolean  trigger UTF-8 compatibility
     * @return  boolean
     */
    public static function alpha($str, $utf8 = false)
    {
        $str = (string)$str;

        if ($utf8 === true)
        {
            return (bool)preg_match('/^\pL++$/uD', $str);
        }
        else
        {
            return ctype_alpha($str);
        }
    }

    /**
     * Checks whether a string consists of alphabetical characters and numbers only.
     *
     * @param   string   input string
     * @param   boolean  trigger UTF-8 compatibility
     * @return  boolean
     */
    public static function alpha_numeric($str, $utf8 = false)
    {
        if ($utf8 === true)
        {
            return (bool)preg_match('/^[\pL\pN]++$/uD', $str);
        }
        else
        {
            return ctype_alnum($str);
        }
    }

    /**
     * Checks whether a string consists of alphabetical characters, numbers, underscores and dashes only.
     *
     * @param   string   input string
     * @param   boolean  trigger UTF-8 compatibility
     * @return  boolean
     */
    public static function alpha_dash($str, $utf8 = false)
    {
        if ($utf8 === true)
        {
            $regex = '/^[-\pL\pN_]++$/uD';
        }
        else
        {
            $regex = '/^[-a-z0-9_]++$/iD';
        }

        return (bool)preg_match($regex, $str);
    }

    /**
     * Checks whether a string consists of digits only (no dots or dashes).
     *
     * @param   string   input string
     * @param   boolean  trigger UTF-8 compatibility
     * @return  boolean
     */
    public static function digit($str, $utf8 = false)
    {
        if ($utf8 === true)
        {
            return (bool)preg_match('/^\pN++$/uD', $str);
        }
        else
        {
            return (is_int($str) && $str >= 0) || ctype_digit($str);
        }
    }

    /**
     * Checks whether a string is a valid number (negative and decimal numbers allowed).
     *
     * Uses {@link http://www.php.net/manual/en/function.localeconv.php locale conversion}
     * to allow decimal point to be locale specific.
     *
     * @param   string   input string
     * @return  boolean
     */
    public static function numeric($str)
    {
        // Get the decimal point for the current locale
        list ($decimal) = array_values(localeconv());

        // A lookahead is used to make sure the string contains at least one digit (before or after the decimal point)
        return (bool)preg_match('/^-?+(?=.*[0-9])[0-9]*+' . preg_quote($decimal) . '?+[0-9]*+$/D', (string)$str);
    }

    /**
     * Tests if a number is within a range.
     *
     * @param   string   number to check
     * @param   integer  minimum value
     * @param   integer  maximum value
     * @return  boolean
     */
    public static function range($number, $min, $max)
    {
        return ($number >= $min && $number <= $max);
    }

    /**
     * Checks if a string is a proper decimal format. Optionally, a specific
     * number of digits can be checked too.
     *
     * @param   string   number to check
     * @param   integer  number of decimal places
     * @param   integer  number of digits
     * @return  boolean
     */
    public static function decimal($str, $places = 2, $digits = NULL)
    {
        if ($digits > 0)
        {
            // Specific number of digits
            $digits = '{' . ((int)$digits) . '}';
        }
        else
        {
            // Any number of digits
            $digits = '+';
        }

        // Get the decimal point for the current locale
        list ( $decimal ) = array_values(localeconv());

        return (bool)preg_match('/^[0-9]' . $digits . preg_quote($decimal) . '[0-9]{' . ((int)$places) . '}$/D', $str);
    }

    /**
     * Checks if a string is a proper hexadecimal HTML color value. The validation
     * is quite flexible as it does not require an initial "#" and also allows for
     * the short notation using only three instead of six hexadecimal characters.
     *
     * @param   string   input string
     * @return  boolean
     */
    public static function color($str)
    {
        return (bool)preg_match('/^#?+[0-9a-f]{3}(?:[0-9a-f]{3})?$/iD', $str);
    }

    /**
     * Checks if a field matches the value of another field.
     *
     * @param   array    array of values
     * @param   string   field name
     * @param   string   field name to match
     * @return  boolean
     */
    public static function matches($array, $field, $match)
    {
        return ($array[$field] === $array[$match]);
    }

} // End Valid
