/*
	Copyright (c) 2004-2008, The Dojo Foundation
	All Rights Reserved.

	Licensed under the Academic Free License version 2.1 or above OR the
	modified BSD license. For more information on Dojo licensing, see:

		http://dojotoolkit.org/book/dojo-book-0-9/introduction/licensing
*/


if(!dojo._hasResource["dojo.data.util.filter"]){ //_hasResource checks added by build. Do not use _hasResource directly in your code.
dojo._hasResource["dojo.data.util.filter"] = true;
dojo.provide("dojo.data.util.filter");

dojo.data.util.filter.patternToRegExp = function(/*String*/pattern, /*boolean?*/ ignoreCase){
	//	summary:  
	//		Helper function to convert a simple pattern to a regular expression for matching.
	//	description:
	//		Returns a regular expression object that conforms to the defined conversion rules.
	//		For example:  
	//			ca*   -> /^ca.*$/
	//			*ca*  -> /^.*ca.*$/
	//			*c\*a*  -> /^.*c\*a.*$/
	//			*c\*a?*  -> /^.*c\*a..*$/
	//			and so on.
	//
	//	pattern: string
	//		A simple matching pattern to convert that follows basic rules:
	//			* Means match anything, so ca* means match anything starting with ca
	//			? Means match single character.  So, b?b will match to bob and bab, and so on.
	//      	\ is an escape character.  So for example, \* means do not treat * as a match, but literal character *.
	//				To use a \ as a character in the string, it must be escaped.  So in the pattern it should be 
	//				represented by \\ to be treated as an ordinary \ character instead of an escape.
	//
	//	ignoreCase:
	//		An optional flag to indicate if the pattern matching should be treated as case-sensitive or not when comparing
	//		By default, it is assumed case sensitive.

	var rxp = "^";
	var c = null;
	for(var i = 0; i < pattern.length; i++){
		c = pattern.charAt(i);
		switch (c) {
			case '\\':
				rxp += c;
				i++;
				rxp += pattern.charAt(i);
				break;
			case '*':
				rxp += ".*"; break;
			case '?':
				rxp += "."; break;
			case '$':
			case '^':
			case '/':
			case '+':
			case '.':
			case '|':
			case '(':
			case ')':
			case '{':
			case '}':
			case '[':
			case ']':
				rxp += "\\"; //fallthrough
			default:
				rxp += c;
		}
	}
	rxp += "$";
	if(ignoreCase){
		return new RegExp(rxp,"i"); //RegExp
	}else{
		return new RegExp(rxp); //RegExp
	}
	
};

}
