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var END_OF_INPUT = -1;
var base64Chars = new Array(
'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','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','0','1','2','3',
'4','5','6','7','8','9','+','/'
);
var reverseBase64Chars = new Array();
for (var i=0; i < base64Chars.length; i++){
reverseBase64Chars[base64Chars[i]] = i;
}
var base64Str;
var base64Count;
function setBase64Str(str){
base64Str = str;
base64Count = 0;
}
function readBase64(){
if (!base64Str) return END_OF_INPUT;
if (base64Count >= base64Str.length) return END_OF_INPUT;
var c = base64Str.charCodeAt(base64Count) & 0xff;
base64Count++;
return c;
}
function encodeBase64(str){
setBase64Str(str);
var result = '';
var inBuffer = new Array(3);
var lineCount = 0;
var done = false;
while (!done && (inBuffer[0] = readBase64()) != END_OF_INPUT){
inBuffer[1] = readBase64();
inBuffer[2] = readBase64();
result += (base64Chars[ inBuffer[0] >> 2 ]);
if (inBuffer[1] != END_OF_INPUT){
result += (base64Chars [(( inBuffer[0] << 4 ) & 0x30) | (inBuffer[1] >> 4) ]);
if (inBuffer[2] != END_OF_INPUT){
result += (base64Chars [((inBuffer[1] << 2) & 0x3c) | (inBuffer[2] >> 6) ]);
result += (base64Chars [inBuffer[2] & 0x3F]);
} else {
result += (base64Chars [((inBuffer[1] << 2) & 0x3c)]);
result += ('=');
done = true;
}
} else {
result += (base64Chars [(( inBuffer[0] << 4 ) & 0x30)]);
result += ('=');
result += ('=');
done = true;
}
lineCount += 4;
if (lineCount >= 76){
result += ('\n');
lineCount = 0;
}
}
return result;
}
function readReverseBase64(){
if (!base64Str) return END_OF_INPUT;
while (true){
if (base64Count >= base64Str.length) return END_OF_INPUT;
var nextCharacter = base64Str.charAt(base64Count);
base64Count++;
if (reverseBase64Chars[nextCharacter]){
return reverseBase64Chars[nextCharacter];
}
if (nextCharacter == 'A') return 0;
}
return END_OF_INPUT;
}
function ntos(n){
n=n.toString(16);
if (n.length == 1) n="0"+n;
n="%"+n;
return unescape(n);
}
function decodeBase64(str){
setBase64Str(str);
var result = "";
var inBuffer = new Array(4);
var done = false;
while (!done && (inBuffer[0] = readReverseBase64()) != END_OF_INPUT
&& (inBuffer[1] = readReverseBase64()) != END_OF_INPUT){
inBuffer[2] = readReverseBase64();
inBuffer[3] = readReverseBase64();
result += ntos((((inBuffer[0] << 2) & 0xff)| inBuffer[1] >> 4));
if (inBuffer[2] != END_OF_INPUT){
result += ntos((((inBuffer[1] << 4) & 0xff)| inBuffer[2] >> 2));
if (inBuffer[3] != END_OF_INPUT){
result += ntos((((inBuffer[2] << 6) & 0xff) | inBuffer[3]));
} else {
done = true;
}
} else {
done = true;
}
}
return result;
}
exports.base64 = encodeBase64;
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