<?php
/*
 * File: ratatoeskr/sys/textprocessors.php
 * Manage text processors (functions that transform text to HTML) and implement some default ones.
 * 
 * License:
 * This file is part of Ratatöskr.
 * Ratatöskr is licensed unter the MIT / X11 License.
 * See "ratatoeskr/licenses/ratatoeskr" for more information.
 */

require_once(dirname(__FILE__) . "/../libs/markdown.php");
require_once(dirname(__FILE__) . "/utils.php");

/*
 * Function: textprocessor_register
 * Register a textprocessor.
 * 
 * Parameters:
 * 	$name               - The name of the textprocessor
 * 	$fx                 - The textprocessor function (function($input), returns HTML)
 * 	$visible_in_backend - Should this textprocessor be visible in the backend? Defaults to True.
 */
function textprocessor_register($name, $fx, $visible_in_backend=True)
{
	global $textprocessors;
	$textprocessors[$name] = array($fx, $visible_in_backend);
}

/*
 * Function: textprocessor_apply
 * Apply a textprocessor on a text.
 * 
 * Parameters:
 * 	$text          - The input text.
 * 	$textprocessor - The name of the textprocessor.
 * 
 * Returns:
 * 	HTML
 */
function textprocessor_apply($text, $textprocessor)
{
	global $textprocessors;
	if(!isset($textprocessors[$textprocessor]))
		throw new Exception("Unknown Textprocessor: $textprocessor");
	
	$fx = @$textprocessors[$textprocessor][0];
	if(!is_callable($fx))
		throw new Exception("Invalid Textprocessor: $textprocessor");
	
	return call_user_func($fx, $text);
}

/*
 * Function: textprocessor_apply_translation
 * Applys a textprocessor automatically on a <Translation> object. The used textprocessor is determined by the $texttype property.
 * 
 * Parameters:
 * 	$translationobj - The <Translation> object.
 * 
 * Returns:
 * 	HTML
 */
function textprocessor_apply_translation($translationobj)
{
	return textprocessor_apply($translationobj->text, $translationobj->texttype);
}

if(!isset($textprocessors))
{
	$textprocessors = array(
		"Markdown" => array("Markdown", True),
		"Plain Text" => array(function($text) { return str_replace(array("\r\n", "\n"), array("<br />", "<br />"), htmlesc($text)); }, True),
		"HTML" => array(function($text) { return $text; }, True)
	);
}

?>