﻿ /***********************************************************************
 * encode and decode          							      	        *
 ************************************************************************
 * Remove Bad Characters                                                *
 * Results:             											    *
 *   - Encoded or Decoded values                                        *
 ***********************************************************************/
 
	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; }}