/*
	 * Base64 Encoding
	 *	
	 */
	function encode_base64( what )
	{
	      var base64_encodetable = "ABCDEFGHIJKLMNOPQRSTUVWXYZabcdefghijklmnopqrstuvwxyz0123456789+/";
	      var result = "";
	      var len = what.length;
	      var x, y;
	      var ptr = 0;
	
	      while( len-- > 0 )
	      {
	            x = what.charCodeAt( ptr++ );
	            result += base64_encodetable.charAt( ( x >> 2 ) & 63 );
	
	            if( len-- <= 0 )
	            {
	                  result += base64_encodetable.charAt( ( x << 4 ) & 63 );
	                  result += "==";
	                  break;
	            }
	
	            y = what.charCodeAt( ptr++ );
	            result += base64_encodetable.charAt( ( ( x << 4 ) | ( ( y >> 4 ) & 15 ) ) & 63 );
	
	            if ( len-- <= 0 )
	            {
	                  result += base64_encodetable.charAt( ( y << 2 ) & 63 );
	                  result += "=";
	                  break;
	            }
	
	            x = what.charCodeAt( ptr++ );
	            result += base64_encodetable.charAt( ( ( y << 2 ) | ( ( x >> 6 ) & 3 ) ) & 63 );
	            result += base64_encodetable.charAt( x & 63 );
	      }
	
	      return result;
	}
	
	/*
	 * ·£´ý¹®ÀÚ¿­ ¸¸µé±â
	 *	
	 */
	function GenRandom(len)
	{
		var arr="0,1,2,3,4,5,6,7,8,9,A,B,C,D,E,F,G,H,I,J,K,L,M,N,O,P,Q,R,S,T,U,V,W,X,Y,Z".split(",");
		var tmp="";
	
		for (var j=0; j<len; j++) {
			tmp+=arr[Math.floor(Math.random()*arr.length)];
		}
	
		return tmp;
	}
	
	/*
	 * ¿¥ÆĽº À¥¸ÞÀÏ Àü´Þ µ¥ÀÌÅÍ Encoding ¹æ½Ä
	 *          
	 *  i)  ¾ÆÀ̵ð(Æò¹®) ¾ÕµÚ·Î ·£´ý¹®ÀÚ¿­ 2byte ¾¿ Ãß°¡ ÈÄ Base64 Encoding
	 *      Base64 Encode((2byte ·£´ý) + Æò¹® + (2byte ·£´ý)) 
	 *  ii) ¾Õ´Ü°èÀÇ °ª¿¡ ¾ÕµÚ·Î ·£´ý¹®ÀÚ¿­ 2byte ¾¿ Ãß°¡ ÈÄ Base64 Encoding
	 *      Base64 Encode((2byte ·£´ý) + ¾Õ´Ü°è°á°ú¹® + (2byte ·£´ý)) 
	 */
	function sdt_encode(plain)
	{		
		var plain1 = GenRandom(2) + plain + GenRandom(2);
		var encode1 = GenRandom(2) + encode_base64(escape(plain1)) + GenRandom(2); 
		var encode2 = encode_base64(escape(encode1));
		
		return encode2;
	}

	/*
	 * ¿¥ÆĽº À¥¸ÞÀÏ Àü´Þ µ¥ÀÌÅÍ decoding ¹æ½Ä
	 *          
	 *  i)  ¾ÆÀ̵ð(Æò¹®) ¾ÕµÚ·Î ·£´ý¹®ÀÚ¿­ 2byte ¾¿ Ãß°¡ ÈÄ Base64 Encoding
	 *      Base64 Encode((2byte ·£´ý) + Æò¹® + (2byte ·£´ý)) 
	 *  ii) ¾Õ´Ü°èÀÇ °ª¿¡ ¾ÕµÚ·Î ·£´ý¹®ÀÚ¿­ 2byte ¾¿ Ãß°¡ ÈÄ Base64 Encoding
	 *      Base64 Encode((2byte ·£´ý) + ¾Õ´Ü°è°á°ú¹® + (2byte ·£´ý)) 
	 */
	function sdt_decode(s)
	{ 
		var decode1 = unescape(Base64.decode(s));
		var temp = decode1.substring(2, decode1.length-2 );
		var decode2 = unescape(Base64.decode(temp));
		var result = decode2.substring(2, decode2.length-2 ); 
		return result; 
	} 

	/**
	*
	*  Base64 encode / decode
	*  http://www.webtoolkit.info/
	*
	**/

	var Base64 = {

		// private property
		_keyStr : "ABCDEFGHIJKLMNOPQRSTUVWXYZabcdefghijklmnopqrstuvwxyz0123456789+/=",

		// public method for encoding
		encode : function (input) {
			var output = "";
			var chr1, chr2, chr3, enc1, enc2, enc3, enc4;
			var i = 0;

			input = Base64._utf8_encode(input);

			while (i < input.length) {

				chr1 = input.charCodeAt(i++);
				chr2 = input.charCodeAt(i++);
				chr3 = input.charCodeAt(i++);

				enc1 = chr1 >> 2;
				enc2 = ((chr1 & 3) << 4) | (chr2 >> 4);
				enc3 = ((chr2 & 15) << 2) | (chr3 >> 6);
				enc4 = chr3 & 63;

				if (isNaN(chr2)) {
					enc3 = enc4 = 64;
				} else if (isNaN(chr3)) {
					enc4 = 64;
				}

				output = output +
				this._keyStr.charAt(enc1) + this._keyStr.charAt(enc2) +
				this._keyStr.charAt(enc3) + this._keyStr.charAt(enc4);

			}

			return output;
		},

		// public method for decoding
		decode : function (input) {
			var output = "";
			var chr1, chr2, chr3;
			var enc1, enc2, enc3, enc4;
			var i = 0;

			input = input.replace(/[^A-Za-z0-9\+\/\=]/g, "");

			while (i < input.length) {

				enc1 = this._keyStr.indexOf(input.charAt(i++));
				enc2 = this._keyStr.indexOf(input.charAt(i++));
				enc3 = this._keyStr.indexOf(input.charAt(i++));
				enc4 = this._keyStr.indexOf(input.charAt(i++));

				chr1 = (enc1 << 2) | (enc2 >> 4);
				chr2 = ((enc2 & 15) << 4) | (enc3 >> 2);
				chr3 = ((enc3 & 3) << 6) | enc4;

				output = output + String.fromCharCode(chr1);

				if (enc3 != 64) {
					output = output + String.fromCharCode(chr2);
				}
				if (enc4 != 64) {
					output = output + String.fromCharCode(chr3);
				}

			}

			output = Base64._utf8_decode(output);

			return output;

		},

		// private method for UTF-8 encoding
		_utf8_encode : function (string) {
			string = string.replace(/\r\n/g,"\n");
			var utftext = "";

			for (var n = 0; n < string.length; n++) {

				var c = string.charCodeAt(n);

				if (c < 128) {
					utftext += String.fromCharCode(c);
				}
				else if((c > 127) && (c < 2048)) {
					utftext += String.fromCharCode((c >> 6) | 192);
					utftext += String.fromCharCode((c & 63) | 128);
				}
				else {
					utftext += String.fromCharCode((c >> 12) | 224);
					utftext += String.fromCharCode(((c >> 6) & 63) | 128);
					utftext += String.fromCharCode((c & 63) | 128);
				}

			}

			return utftext;
		},

		// private method for UTF-8 decoding
		_utf8_decode : function (utftext) {
			var string = "";
			var i = 0;
			var c = c1 = c2 = 0;

			while ( i < utftext.length ) {

				c = utftext.charCodeAt(i);

				if (c < 128) {
					string += String.fromCharCode(c);
					i++;
				}
				else if((c > 191) && (c < 224)) {
					c2 = utftext.charCodeAt(i+1);
					string += String.fromCharCode(((c & 31) << 6) | (c2 & 63));
					i += 2;
				}
				else {
					c2 = utftext.charCodeAt(i+1);
					c3 = utftext.charCodeAt(i+2);
					string += String.fromCharCode(((c & 15) << 12) | ((c2 & 63) << 6) | (c3 & 63));
					i += 3;
				}

			}

			return string;
		},
		
		URLEncode : function (string) {   
			return escape(this._utf8_encode(string));   
		},   
	  
		// public method for url decoding   
		URLDecode : function (string) {   
			return this._utf8_decode(unescape(string));   
		}
	}