all-in-one-event-calendar/lib/date/validator.php

<?php

/**
 * Validation utility library
 *
 * @author     Timely Network Inc
 * @since      2012.08.21
 *
 * @package    AllInOneCalendar
 * @subpackage AllInOneCalendar.Lib.Utility
 */
class Ai1ec_Validation_Utility {

    /**
     * Check if the date supplied is valid. It validates $date in the format given
     * by $pattern, which matches one of the supported date patterns.
     *
     * @param  string  $date    Date string to validate
     * @param  string  $pattern Key of date pattern (@see
     *                          self::get_date_patterns()) to
     *                          match date string against
     * @return boolean
     */
    static public function validate_date( $date, $pattern = 'def' ) {
        $result = self::validate_date_and_return_parsed_date( $date, $pattern );
        if( $result === false ) {
            return false;
        }
        return true;
    }

    /**
     * Check if the date supplied is valid. It validates date in the format given
     * by $pattern, which matches one of the supported date patterns.
     *
     * @param string $date    Date string to parse
     * @param string $pattern Key of date pattern (@see
     *                        self::get_date_patterns()) to
     *                        match date string against
     * @return array|boolean An array with the parsed date or false if the date
     *                       is not valid.
     */
    static public function validate_date_and_return_parsed_date(
        $date, $pattern = 'def'
    ) {
        $pattern = self::_get_pattern_regexp( $pattern );
        if ( preg_match( $pattern, $date, $matches ) ) {
            if ( checkdate( $matches['m'], $matches['d'], $matches['y'] ) ) {
                return array(
                    'month' => $matches['m'],
                    'day'   => $matches['d'],
                    'year'  => $matches['y'],
                );
            }
        }
        return false;
    }

    /**
     * Convert input into a valid ISO date.
     *
     * @param string $date    Date to convert to ISO.
     * @param string $pattern Format used to store it.
     *
     * @return string|bool Re-formatted date or false on failure.
     */
    static public function format_as_iso( $date, $pattern = 'def' ) {
        $regexp = self::_get_pattern_regexp( $pattern );
        if ( ! preg_match( $regexp, $date, $matches ) ) {
            return false;
        }
        return sprintf(
            '%04d-%02d-%02d',
            $matches['y'],
            $matches['m'],
            $matches['d']
        );
    }

    /**
     * Create regexp with named groups to match positional elements.
     *
     * @param string $pattern Pattern to convert.
     *
     * @return string Regular expression pattern.
     */
    static protected function _get_pattern_regexp( $pattern ) {
        $pattern = self::get_date_pattern_by_key( $pattern );
        $pattern = preg_quote( $pattern, '/' );
        $pattern = str_replace(
            array( 'dd',           'd',              'mm',           'm',              'yyyy',         'yy' ),
            array( '(?P<d>\d{2})', '(?P<d>\d{1,2})', '(?P<m>\d{2})', '(?P<m>\d{1,2})', '(?P<y>\d{4})', '(?P<y>\d{2})' ),
            $pattern
        );
        // Accept hyphens and dots in place of forward slashes (for URLs).
        $pattern = str_replace( '\/', '[\/\-\.]', $pattern );
        return '#^' . $pattern . '$#';
    }

    /**
     * Check if the string or integer is a valid timestamp.
     *
     * @see http://stackoverflow.com/questions/2524680/check-whether-the-string-is-a-unix-timestamp
     * @param string|int $timestamp
     * @return boolean
     */
    static public function is_valid_time_stamp( $timestamp ) {
        return
            (
                is_int( $timestamp ) ||
                ( (string)(int)$timestamp ) === (string)$timestamp
            )
            && ( $timestamp <= PHP_INT_MAX )
            && ( $timestamp >= 0 /*~ PHP_INT_MAX*/ );
        // do not allow negative timestamps until this is widely accepted
    }

    /**
     * Returns the associative array of date patterns supported by the plugin,
     * currently:
     *   array(
     *     'def' => 'd/m/yyyy',
     *     'us'  => 'm/d/yyyy',
     *     'iso' => 'yyyy-m-d',
     *     'dot' => 'm.d.yyyy',
     *   );
     *
     * 'd' or 'dd' represent the day, 'm' or 'mm' represent the month, and 'yy'
     * or 'yyyy' represent the year.
     *
     * @return array Supported date patterns
     */
    static public function get_date_patterns() {
        return array(
            'def' => 'd/m/yyyy',
            'us'  => 'm/d/yyyy',
            'iso' => 'yyyy-m-d',
            'dot' => 'm.d.yyyy',
        );
    }

    /**
     * Returns the date pattern (in the form 'd-m-yyyy', for example) associated
     * with the provided key, used by plugin settings. Simply a static map as
     * follows:
     *
     * @param  string $key Key for the date format
     * @return string      Associated date format pattern
     */
    static public function get_date_pattern_by_key( $key = 'def' ) {
        $patterns = self::get_date_patterns();
        return $patterns[$key];
    }

}