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| 1 | + |
| 2 | +/** |
| 3 | +* |
| 4 | +* Base64 encode / decode |
| 5 | +* http://www.webtoolkit.info/ |
| 6 | +* |
| 7 | +**/ |
| 8 | + |
| 9 | +var Base64 = { |
| 10 | + |
| 11 | + // private property |
| 12 | + _keyStr : "ABCDEFGHIJKLMNOPQRSTUVWXYZabcdefghijklmnopqrstuvwxyz0123456789+/=", |
| 13 | + |
| 14 | + // public method for encoding |
| 15 | + encode : function (input) { |
| 16 | + var output = ""; |
| 17 | + var chr1, chr2, chr3, enc1, enc2, enc3, enc4; |
| 18 | + var i = 0; |
| 19 | + |
| 20 | + input = Base64._utf8_encode(input); |
| 21 | + |
| 22 | + while (i < input.length) { |
| 23 | + |
| 24 | + chr1 = input.charCodeAt(i++); |
| 25 | + chr2 = input.charCodeAt(i++); |
| 26 | + chr3 = input.charCodeAt(i++); |
| 27 | + |
| 28 | + enc1 = chr1 >> 2; |
| 29 | + enc2 = ((chr1 & 3) << 4) | (chr2 >> 4); |
| 30 | + enc3 = ((chr2 & 15) << 2) | (chr3 >> 6); |
| 31 | + enc4 = chr3 & 63; |
| 32 | + |
| 33 | + if (isNaN(chr2)) { |
| 34 | + enc3 = enc4 = 64; |
| 35 | + } else if (isNaN(chr3)) { |
| 36 | + enc4 = 64; |
| 37 | + } |
| 38 | + |
| 39 | + output = output + |
| 40 | + this._keyStr.charAt(enc1) + this._keyStr.charAt(enc2) + |
| 41 | + this._keyStr.charAt(enc3) + this._keyStr.charAt(enc4); |
| 42 | + |
| 43 | + } |
| 44 | + |
| 45 | + return output; |
| 46 | + }, |
| 47 | + |
| 48 | + // public method for decoding |
| 49 | + decode : function (input) { |
| 50 | + var output = ""; |
| 51 | + var chr1, chr2, chr3; |
| 52 | + var enc1, enc2, enc3, enc4; |
| 53 | + var i = 0; |
| 54 | + |
| 55 | + input = input.replace(/[^A-Za-z0-9\+\/\=]/g, ""); |
| 56 | + |
| 57 | + while (i < input.length) { |
| 58 | + |
| 59 | + enc1 = this._keyStr.indexOf(input.charAt(i++)); |
| 60 | + enc2 = this._keyStr.indexOf(input.charAt(i++)); |
| 61 | + enc3 = this._keyStr.indexOf(input.charAt(i++)); |
| 62 | + enc4 = this._keyStr.indexOf(input.charAt(i++)); |
| 63 | + |
| 64 | + chr1 = (enc1 << 2) | (enc2 >> 4); |
| 65 | + chr2 = ((enc2 & 15) << 4) | (enc3 >> 2); |
| 66 | + chr3 = ((enc3 & 3) << 6) | enc4; |
| 67 | + |
| 68 | + output = output + String.fromCharCode(chr1); |
| 69 | + |
| 70 | + if (enc3 != 64) { |
| 71 | + output = output + String.fromCharCode(chr2); |
| 72 | + } |
| 73 | + if (enc4 != 64) { |
| 74 | + output = output + String.fromCharCode(chr3); |
| 75 | + } |
| 76 | + |
| 77 | + } |
| 78 | + |
| 79 | + output = Base64._utf8_decode(output); |
| 80 | + |
| 81 | + return output; |
| 82 | + |
| 83 | + }, |
| 84 | + |
| 85 | + // private method for UTF-8 encoding |
| 86 | + _utf8_encode : function (string) { |
| 87 | + string = string.replace(/\r\n/g,"\n"); |
| 88 | + var utftext = ""; |
| 89 | + |
| 90 | + for (var n = 0; n < string.length; n++) { |
| 91 | + |
| 92 | + var c = string.charCodeAt(n); |
| 93 | + |
| 94 | + if (c < 128) { |
| 95 | + utftext += String.fromCharCode(c); |
| 96 | + } |
| 97 | + else if((c > 127) && (c < 2048)) { |
| 98 | + utftext += String.fromCharCode((c >> 6) | 192); |
| 99 | + utftext += String.fromCharCode((c & 63) | 128); |
| 100 | + } |
| 101 | + else { |
| 102 | + utftext += String.fromCharCode((c >> 12) | 224); |
| 103 | + utftext += String.fromCharCode(((c >> 6) & 63) | 128); |
| 104 | + utftext += String.fromCharCode((c & 63) | 128); |
| 105 | + } |
| 106 | + |
| 107 | + } |
| 108 | + |
| 109 | + return utftext; |
| 110 | + }, |
| 111 | + |
| 112 | + // private method for UTF-8 decoding |
| 113 | + _utf8_decode : function (utftext) { |
| 114 | + var string = ""; |
| 115 | + var i = 0; |
| 116 | + var c = c1 = c2 = 0; |
| 117 | + |
| 118 | + while ( i < utftext.length ) { |
| 119 | + |
| 120 | + c = utftext.charCodeAt(i); |
| 121 | + |
| 122 | + if (c < 128) { |
| 123 | + string += String.fromCharCode(c); |
| 124 | + i++; |
| 125 | + } |
| 126 | + else if((c > 191) && (c < 224)) { |
| 127 | + c2 = utftext.charCodeAt(i+1); |
| 128 | + string += String.fromCharCode(((c & 31) << 6) | (c2 & 63)); |
| 129 | + i += 2; |
| 130 | + } |
| 131 | + else { |
| 132 | + c2 = utftext.charCodeAt(i+1); |
| 133 | + c3 = utftext.charCodeAt(i+2); |
| 134 | + string += String.fromCharCode(((c & 15) << 12) | ((c2 & 63) << 6) | (c3 & 63)); |
| 135 | + i += 3; |
| 136 | + } |
| 137 | + |
| 138 | + } |
| 139 | + |
| 140 | + return string; |
| 141 | + } |
| 142 | + |
| 143 | +} |
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