
// {{{ base64_decode
function base64_decode( data ) {
    // Decodes data encoded with MIME base64
    // 
    // +    discuss at: http://kevin.vanzonneveld.net/techblog/article/javascript_equivalent_for_phps_base64_decode/
    // +       version: 805.821
    // +   original by: Tyler Akins (http://rumkin.com)
    // +   improved by: Thunder.m
    // +      input by: Aman Gupta
    // +   improved by: Kevin van Zonneveld (http://kevin.vanzonneveld.net)    
    // -    depends on: utf8_decode
    // *     example 1: base64_decode('S2V2aW4gdmFuIFpvbm5ldmVsZA==');
    // *     returns 1: 'Kevin van Zonneveld'
    
    // mozilla has this native 
    // - but breaks in 2.0.0.12!
    //if (typeof window['btoa'] == 'function') {
    //    return btoa(data);
    //}
    
    var b64 = "ABCDEFGHIJKLMNOPQRSTUVWXYZabcdefghijklmnopqrstuvwxyz0123456789+/=";
    var o1, o2, o3, h1, h2, h3, h4, bits, i = ac = 0, dec = "", tmp_arr = [];

    do {  // unpack four hexets into three octets using index points in b64
        h1 = b64.indexOf(data.charAt(i++));
        h2 = b64.indexOf(data.charAt(i++));
        h3 = b64.indexOf(data.charAt(i++));
        h4 = b64.indexOf(data.charAt(i++));

        bits = h1<<18 | h2<<12 | h3<<6 | h4;

        o1 = bits>>16 & 0xff;
        o2 = bits>>8 & 0xff;
        o3 = bits & 0xff;

        if (h3 == 64) {
            tmp_arr[ac++] = String.fromCharCode(o1);
        } else if (h4 == 64) {
            tmp_arr[ac++] = String.fromCharCode(o1, o2);
        } else {
            tmp_arr[ac++] = String.fromCharCode(o1, o2, o3);
        }
    } while (i < data.length);
    
    dec = tmp_arr.join('');
    dec = utf8_decode(dec);
    
    return dec;
}// }}}

// {{{ utf8_encode
function utf8_encode ( string ) {
    // Encodes an ISO-8859-1 string to UTF-8
    // 
    // +    discuss at: http://kevin.vanzonneveld.net/techblog/article/javascript_equivalent_for_phps_utf8_encode/
    // +       version: 808.2719
    // +   original by: Webtoolkit.info (http://www.webtoolkit.info/)
    // +   improved by: Kevin van Zonneveld (http://kevin.vanzonneveld.net)
    // +   improved by: sowberry
    // *     example 1: utf8_encode('Kevin van Zonneveld');
    // *     returns 1: 'Kevin van Zonneveld'
    
    string = string.replace(/\r\n/g,"\n");
    var utftext = "";
    var start, end;
 
    start = end = 0;
    for (var n = 0; n < string.length; n++) {
        var c = string.charCodeAt(n);
        var enc = null;
 
        if (c < 128) {
            end++;
        } else if((c > 127) && (c < 2048)) {
            enc = String.fromCharCode((c >> 6) | 192) + String.fromCharCode((c & 63) | 128);
        } else {
            enc = String.fromCharCode((c >> 12) | 224) + String.fromCharCode(((c >> 6) & 63) | 128) + String.fromCharCode((c & 63) | 128);
        }
        if (enc != null) {
            if (end > start) {
                utftext += string.substring(start, end);
            }
            utftext += enc;
            start = end = n+1;
        }
    }
    
    if (end > start) {
        utftext += string.substring(start, string.length);
    }
 
    return utftext;
}// }}}

// {{{ utf8_decode
function utf8_decode ( str_data ) {
    // Converts a string with ISO-8859-1 characters encoded with UTF-8   to single-byte
    // ISO-8859-1
    // 
    // +    discuss at: http://kevin.vanzonneveld.net/techblog/article/javascript_equivalent_for_phps_utf8_decode/
    // +       version: 805.821
    // +   original by: Webtoolkit.info (http://www.webtoolkit.info/)
    // +      input by: Aman Gupta
    // +   improved by: Kevin van Zonneveld (http://kevin.vanzonneveld.net)
    // *     example 1: utf8_decode('Kevin van Zonneveld');
    // *     returns 1: 'Kevin van Zonneveld'

    var tmp_arr = [], i = ac = c = c1 = c2 = 0;

    while ( i < str_data.length ) {
        c = str_data.charCodeAt(i);
        if (c < 128) {
            tmp_arr[ac++] = String.fromCharCode(c); 
            i++;
        } else if ((c > 191) && (c < 224)) {
            c2 = str_data.charCodeAt(i+1);
            tmp_arr[ac++] = String.fromCharCode(((c & 31) << 6) | (c2 & 63));
            i += 2;
        } else {
            c2 = str_data.charCodeAt(i+1);
            c3 = str_data.charCodeAt(i+2);
            tmp_arr[ac++] = String.fromCharCode(((c & 15) << 12) | ((c2 & 63) << 6) | (c3 & 63));
            i += 3;
        }
    }
    
    return tmp_arr.join('');
}// }}}


// {{{ base64_encode
function base64_encode( data ) {
    // Encodes data with MIME base64
    // 
    // +    discuss at: http://kevin.vanzonneveld.net/techblog/article/javascript_equivalent_for_phps_base64_encode/
    // +       version: 805.821
    // +   original by: Tyler Akins (http://rumkin.com)
    // +   improved by: Bayron Guevara
    // +   improved by: Thunder.m
    // +   improved by: Kevin van Zonneveld (http://kevin.vanzonneveld.net)        
    // -    depends on: utf8_encode
    // *     example 1: base64_encode('Kevin van Zonneveld');
    // *     returns 1: 'S2V2aW4gdmFuIFpvbm5ldmVsZA=='

    // mozilla has this native
    // - but breaks in 2.0.0.12!
    //if (typeof window['atob'] == 'function') {
    //    return atob(data);
    //}
        
    var b64 = "ABCDEFGHIJKLMNOPQRSTUVWXYZabcdefghijklmnopqrstuvwxyz0123456789+/=";
    var o1, o2, o3, h1, h2, h3, h4, bits, i = ac = 0, enc="", tmp_arr = [];
    data = utf8_encode(data);
    //data = utf8_decode(data);
    do { // pack three octets into four hexets
        o1 = data.charCodeAt(i++);
        o2 = data.charCodeAt(i++);
        o3 = data.charCodeAt(i++);

        bits = o1<<16 | o2<<8 | o3;

        h1 = bits>>18 & 0x3f;
        h2 = bits>>12 & 0x3f;
        h3 = bits>>6 & 0x3f;
        h4 = bits & 0x3f;

        // use hexets to index into b64, and append result to encoded string
        tmp_arr[ac++] = b64.charAt(h1) + b64.charAt(h2) + b64.charAt(h3) + b64.charAt(h4);
    } while (i < data.length);
    
    enc = tmp_arr.join('');
    
    switch( data.length % 3 ){
        case 1:
            enc = enc.slice(0, -2) + '==';
        break;
        case 2:
            enc = enc.slice(0, -1) + '=';
        break;
    }

    return enc;
}// }}}

