share/nitdoc/js/lib/base64.js

   1 var Base64 = {
   2
   3         // private property
   4         _keyStr : "ABCDEFGHIJKLMNOPQRSTUVWXYZabcdefghijklmnopqrstuvwxyz0123456789+/=",
   5
   6         // public method for encoding
   7         encode : function (input) {
   8                 var output = "";
   9                 var chr1, chr2, chr3, enc1, enc2, enc3, enc4;
  10                 var i = 0;
  11
  12                 input = Base64._utf8_encode(input);
  13
  14                 while (i < input.length) {
  15
  16                         chr1 = input.charCodeAt(i++);
  17                         chr2 = input.charCodeAt(i++);
  18                         chr3 = input.charCodeAt(i++);
  19
  20                         enc1 = chr1 >> 2;
  21                         enc2 = ((chr1 & 3) << 4) | (chr2 >> 4);
  22                         enc3 = ((chr2 & 15) << 2) | (chr3 >> 6);
  23                         enc4 = chr3 & 63;
  24
  25                         if (isNaN(chr2)) {
  26                                 enc3 = enc4 = 64;
  27                         } else if (isNaN(chr3)) {
  28                                 enc4 = 64;
  29                         }
  30
  31                         output = output +
  32                         this._keyStr.charAt(enc1) + this._keyStr.charAt(enc2) +
  33                         this._keyStr.charAt(enc3) + this._keyStr.charAt(enc4);
  34
  35                 }
  36
  37                 return output;
  38         },
  39
  40         // public method for decoding
  41         decode : function (input) {
  42                 var output = "";
  43                 var chr1, chr2, chr3;
  44                 var enc1, enc2, enc3, enc4;
  45                 var i = 0;
  46
  47                 input = input.replace(/[^A-Za-z0-9\+\/\=]/g, "");
  48
  49                 while (i < input.length) {
  50
  51                         enc1 = this._keyStr.indexOf(input.charAt(i++));
  52                         enc2 = this._keyStr.indexOf(input.charAt(i++));
  53                         enc3 = this._keyStr.indexOf(input.charAt(i++));
  54                         enc4 = this._keyStr.indexOf(input.charAt(i++));
  55
  56                         chr1 = (enc1 << 2) | (enc2 >> 4);
  57                         chr2 = ((enc2 & 15) << 4) | (enc3 >> 2);
  58                         chr3 = ((enc3 & 3) << 6) | enc4;
  59
  60                         output = output + String.fromCharCode(chr1);
  61
  62                         if (enc3 != 64) {
  63                                 output = output + String.fromCharCode(chr2);
  64                         }
  65                         if (enc4 != 64) {
  66                                 output = output + String.fromCharCode(chr3);
  67                         }
  68
  69                 }
  70
  71                 output = Base64._utf8_decode(output);
  72
  73                 return output;
  74
  75         },
  76
  77         // private method for UTF-8 encoding
  78         _utf8_encode : function (string) {
  79                 string = string.replace(/\r\n/g,"\n");
  80                 var utftext = "";
  81
  82                 for (var n = 0; n < string.length; n++) {
  83
  84                         var c = string.charCodeAt(n);
  85
  86                         if (c < 128) {
  87                                 utftext += String.fromCharCode(c);
  88                         }
  89                         else if((c > 127) && (c < 2048)) {
  90                                 utftext += String.fromCharCode((c >> 6) | 192);
  91                                 utftext += String.fromCharCode((c & 63) | 128);
  92                         }
  93                         else {
  94                                 utftext += String.fromCharCode((c >> 12) | 224);
  95                                 utftext += String.fromCharCode(((c >> 6) & 63) | 128);
  96                                 utftext += String.fromCharCode((c & 63) | 128);
  97                         }
  98
  99                 }
 100
 101                 return utftext;
 102         },
 103
 104         // private method for UTF-8 decoding
 105         _utf8_decode : function (utftext) {
 106                 var string = "";
 107                 var i = 0;
 108                 var c = c1 = c2 = 0;
 109
 110                 while ( i < utftext.length ) {
 111
 112                         c = utftext.charCodeAt(i);
 113
 114                         if (c < 128) {
 115                                 string += String.fromCharCode(c);
 116                                 i++;
 117                         }
 118                         else if((c > 191) && (c < 224)) {
 119                                 c2 = utftext.charCodeAt(i+1);
 120                                 string += String.fromCharCode(((c & 31) << 6) | (c2 & 63));
 121                                 i += 2;
 122                         }
 123                         else {
 124                                 c2 = utftext.charCodeAt(i+1);
 125                                 c3 = utftext.charCodeAt(i+2);
 126                                 string += String.fromCharCode(((c & 15) << 12) | ((c2 & 63) << 6) | (c3 & 63));
 127                                 i += 3;
 128                         }
 129
 130                 }
 131
 132                 return string;
 133         }
 134 }
 135