<?php
/**
 * DateValidator.class.php
 *
 * This file contains the definition of the DateValidator class.
 *
 * @package SolidWorks
 * @author John Diamond <hide@address.com>
 * @copyright John Diamond <hide@address.com>
 * @license http://www.opensource.org/licenses/gpl-license.php GNU Public License
 */

// Exceptions
require BASE_PATH . "solidworks/widgets/InvalidDateInputFormatException.class.php";
require BASE_PATH . "solidworks/exceptions/InvalidDateException.class.php";

/**
 * DateValidator
 *
 * @package SolidWorks
 * @author John Diamond <hide@address.com>
 */
class DateValidator extends TextValidator {
	/**
	 * @var string Date input format: MDY or DMY
	 */
	private $format = "MDY";

	/**
	 * Date Widget Constructor
	 *
	 * @param string $formName The name of the form this widget belongs to
	 * @param string $fieldName The name of the field this widget represents
	 * @param array $fieldConfig The configuration for this field
	 * @param string $format Date input format: MDY or DMY
	 */
	public function __construct( $formName, $fieldName, $fieldConfig, $format = "MDY" ) {
		parent::__construct( $formName, $fieldName, $fieldConfig );
		$this->setFormat( $format );
	}

	/**
	 * Get Date Input Format
	 *
	 * @return string Date input format: MDY or DMY
	 */
	public function getFormat() {
		return $this->format;
	}

	/**
	 * Set Date Input Format
	 *
	 * @param string $format Date input format: MDY or DMY
	 * @throws InvalidDateInputFormat
	 */
	public function setFormat( $format ) {
		if ( !($format == "MDY" || $format == "DMY") ) {
			throw new InvalidDateInputFormatException( $format );
		}

		$this->format = $format;
	}

	/**
	 * Validate a Date Field
	 *
	 * Date's may only contain numbers, seperated by a '/' or a '-', be in one of
	 * the following formats: MM/DD/YYYY, DD/MM/YYYY (the year may also be 2 digits
	 * instead of 4), and must be a legal date.
	 *
	 * @param string $data Field data
	 * @return int Date as a timestamp value
	 * @throws InvalidDateException
	 */
	public function validate( $data ) {
		$data = parent::validate( $data );
		$data = $this->validateDate( $data );
		return $data;
	}

	/**
	 * Validate a Date
	 *
	 * @param string $data Field data
	 * @return string This function may alter data before validating it, if so this is the result
	 * @throws InvalidDateException
	 */
	protected function validateDate( $data ) {
		// Strip out white space and valid characters: '/' and '-'
		$data = preg_replace( "|([ 	]+)|", "", $data );
		$data = preg_replace("|[-/]|", " ", $data );

		// Explode the date into an array
		$components = explode( " ", $data );
		if ( !$components || count( $components ) != 3 ) {
			throw new InvalidDateException();
		}

		// Verify that the components are all numerical
		if ( !ctype_digit( $components[0] ) ||
				!ctype_digit( $components[1] ) ||
				!ctype_digit( $components[2] ) ) {
			throw new InvalidDateException();
		}

		// Extract day, month, and year
		$day = $components[$this->getFormat() == "DMY" ? 0 : 1];
		$month = $components[$this->getFormat() == "DMY" ? 1 : 0];
		$year = $components[2];

		// If the year is only 2 digits: < 70 = add 2000, > 70 = add 1900
		if ( strlen( $year ) < 4 ) {
			$year += intval( $year ) > 70 ? 1900 : 2000;
		}

		// Verify that the date is legal
		if ( !checkdate( $month, $day, $year ) ) {
			throw new InvalidDateException();
		}

		// Return the date as an integer timestamp
		if ( ($data = mktime( 0, 0, 0, $month, $day, $year )) < 1 ) {
			throw new InvalidDateException();
		}

		return $data;
	}
}
?>