<?php

/**
 * Plugin Name: 300form
 * Description: Simple form validation class with less than 300 lines of code. Supports dynamic form fields.
 * Version: 0.2.1a
 * Author: Michael Schröder <ms@ts-webdesign.net>
 * TextDomain: 300form
 * DomainPath: /l10n
 */
if ( !class_exists( 'form' ) ) {

	class form {

		/**
		 * Contains obligatory fields.
		 * @var array 
		 */
		public $required;

		/**
		 * Contains regular expressions to match user input against.
		 * @var array
		 */
		public $pattern;

		/**
		 * Form field alerts.
		 * @var array
		 */
		public $hint;

		/**
		 * The processed data.
		 * @var array
		 */
		public $processed_data;

		/**
		 * The textdomain string
		 * @var string 
		 */
		private $textdomain;

		/**
		 * Get a value of the plugin header
		 *
		 * @access private
		 * @uses get_plugin_data, ABSPATH
		 * @param string $value
		 * @return string The plugin header value
		 * @since 0.1a
		 */
		private function get_plugin_header( $value = 'TextDomain' ) {

			if ( !function_exists( 'get_plugin_data' ) )
				require_once( ABSPATH . '/wp-admin/includes/plugin.php' );
			$plugin_data = get_plugin_data( __FILE__ );
			return $plugin_data[ $value ];
		}

		/**
		 * Get the Textdomain
		 *
		 * @access private
		 * @return string | The plugins' textdomain
		 * @since 0.1a
		 */
		private function get_textdomain() {

			if ( empty( $this->textdomain ) )
				$this->textdomain = $this->get_plugin_header( 'TextDomain' );

			return $this->textdomain;
		}

		/**
		 * Process form
		 * 
		 * @access public
		 * @param array $data | Form data to validate
		 * @return TRUE | All checks passed
		 * @return FALSE | checks not passed
		 * @since 0.1a
		 */
		public function process( $data ) {

			// Nothing to do?
			if ( FALSE == $data )
				return FALSE;

			// Validate user input
			// 1. obligatory fields
			// 2. match patterns
			$oblig = $this->obligatory( $data );

			$pattern = $this->pattern( $data );

			if ( FALSE === $oblig || FALSE === $pattern ) {

				$this->request_to_form( $data );
				return FALSE;
			}

			// If all checks are passed successfully,
			// we will make the data accessible after applying a filter:
			$this->processed_data = apply_filters( 'form_processed_data', $data );

			return TRUE;
		}

		/**
		 * Check input for obligatory fields
		 * 
		 * @TODO use apply_filters for required data
		 * 
		 * @access private
		 * @param array $data | the REQUEST data
		 * @return TRUE | all required fields are filled out
		 * @return FALSE | a required field is not filled out
		 * @since 0.1a
		 */
		private function obligatory( $data ) {

			if ( ! isset( $this->required ) || ! is_array( $this->required ) || FALSE == $data )
				return TRUE;

			foreach ( $this->required AS $input_name ) 
				if ( empty( $data[ $input_name ] ) )
					$this->hint[ $input_name ] = __( 'This field is required!', $this->textdomain );


			return TRUE;
		}

		/**
		 * Check user input
		 * 
		 * @TODO use apply_filters for pattern data
		 * 
		 * @access private
		 * @param array $data | the REQUEST data
		 * @return TRUE | all fields match their pattern
		 * @return FALSE | a field does not match it's pattern
		 * @since 0.1a
		 */
		private function pattern( $data ) {

			if ( ! isset( $this->pattern ) || ! is_array( $this->pattern ) || FALSE == $data )
				return TRUE;

			foreach ( $this->pattern AS $input_name => $regex ) {
				// REQUEST array
				if ( !empty( $data[ $input_name ] ) && is_array( $data[ $input_name ] ) ) {
					foreach ( $data[ $input_name ] as $key => $value ) {
						// Obligatory with non-matching pattern
						if ( ( array_key_exists( $input_name, $data ) ) && // is there a pattern?
								!preg_match( $regex, stripslashes( $value ) ) && // is the pattern matching?
								in_array( $input_name, $this->required ) ) { // is this obligatory?
							if ( empty( $this->hint[ $input_name ] ) ) : $this->hint[ $input_name ] = __( 'Check your input!', $this->textdomain );
							endif;
						}
						// Non-obligatory, but an input must always match it's pattern
						if ( !in_array( $input_name, $this->required ) && // non-obligatory?
								!empty( $data[ $input_name ] ) && // but there is an input?
								!preg_match( $regex, stripslashes( $value ) ) ) { // not matching?
							if ( empty( $this->hint[ $input_name ] ) ) : $this->hint[ $input_name ] = __( 'Check your input!', $this->textdomain );
							endif;
						}
					}
				}
				else {
					// Obligatory with non-matching pattern
					if ( array_key_exists( $input_name, $data ) && // is there a pattern?
							!preg_match( $regex, stripslashes( $data[ $input_name ] ) ) && // is the pattern matching?
							in_array( $input_name, $this->required ) ) { // is this obligatory?
						if ( empty( $this->hint[ $input_name ] ) ) : $this->hint[ $input_name ] = __( 'Check your input!', $this->textdomain );
						endif;
					}
					// Non-obligatory, but an input must always match it's pattern
					if ( !in_array( $input_name, $this->required ) && // non-obligatory?
							!empty( $data[ $input_name ] ) && // but there is an input?
							!preg_match( $regex, stripslashes( $data[ $input_name ] ) ) ) {  // not matching?
						if ( empty( $this->hint[ $input_name ] ) ) : $this->hint[ $input_name ] = __( 'Check your input!', $this->textdomain );
						endif;
					}
				}
			}

			if ( !empty( $this->hint ) )
				return FALSE;

			return TRUE;
		}

		/**
		 * Load REQUEST data into class var for
		 * displaying form field values.
		 * 
		 * @access private
		 * @param $data | REQUEST data
		 * @since 0.1a
		 */
		private function request_to_form( $data ) {

			foreach ( $data AS $field_key => $value ) {
				if ( is_array( $value ) ) {
					foreach ( $value as $key => $val ) {
						// Is this a dynamic field?
						if ( 0 === strpos( $field_key, "dyn-" ) )
							$this->form_data[ $key ] = $val;
						else
							$this->form_data[ $val ] = $val;
					}
				}
				else
					$this->form_data[ $field_key ] = $value;
			}

			return TRUE;
		}

		/**
		 * Return a form field value
		 *
		 * @access public
		 * @param string $field | the field name
		 * @param string $default | the optional default field value
		 * @return string $output | field value
		 * @since 0.1a
		 */
		public function get_data( $field, $default = FALSE ) {

			$output = '';

			if ( !is_string( $field ) )
				return $output;

			if ( !empty( $this->form_data[ $field ] ) )
				$output = $this->form_data[ $field ];
			else
				$output = ( FALSE == $default ) ? '' : $default;

			return $output;
		}

		/**
		 * Print a field value
		 * 
		 * @access public
		 * @param string $field | the field name
		 * @param string $default | the optional default field value
		 * @since 0.1a
		 */
		public function data( $field, $default = FALSE ) {

			echo $this->get_data( $field, $default );
		}

		/**
		 * Get this form element's hint. Displays
		 * a default hint if none is provided.
		 * 
		 * @access public
		 * @param string $field | the field name
		 * @param string $hint | optional field hint
		 * @return string | the field hint, i.e. "Please fill out this field!"
		 * @since 0.1a
		 */
		public function get_hint( $field, $hint = FALSE ) {

			$field = ( string ) $field;

			if ( empty( $this->hint[ $field ] ) )
				return '';
			else
				return ( FALSE == $hint ) ? $this->hint[ $field ] : $hint;
		}

		/**
		 * Print  form element's hint.
		 * 
		 * @access public
		 * @param string $field | the field name
		 * @param string $hint | optional field hint
		 * @since 0.1a
		 */
		public function hint( $field, $hint = FALSE ) {

			echo $this->get_hint( $field, $hint );
		}

	}

}
?>