webui-aria2/js/services/base64.js

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app.factory('$base64', [function() {
var obj = {};
var a64 = 'ABCDEFGHIJKLMNOPQRSTUVWXYZabcdefghijklmnopqrstuvwxyz0123456789+/',
a256 = {
indexOf: function (c) {
return c.charCodeAt(0);
},
charAt: String.fromCharCode
};
function code(s, discard, alpha, beta, w1, w2) {
s = String(s);
var b = 0, x = '', i, c, bs = 1, sb = 1, length = s.length, tmp;
for (i = 0; i < length || (!discard && sb > 1); i += 1) {
b *= w1;
bs *= w1;
if (i < length) {
c = alpha.indexOf(s.charAt(i));
if (c <= -1 || c >= w1) {
throw new RangeError();
}
sb *= w1;
b += c;
}
while (bs >= w2) {
bs /= w2;
if (sb > 1) {
tmp = b;
b %= bs;
x += beta.charAt((tmp - b) / bs);
sb /= w2;
}
}
}
return x;
}
obj.btoa = function (s) {
s = code(s, false, a256, a64, 256, 64);
return s + '===='.slice((s.length % 4) || 4);
};
obj.atob = function (s) {
var i;
s = String(s).split('=');
for (i = s.length - 1; i >= 0; i -= 1) {
if (s[i].length % 4 === 1) {
throw new RangeError();
}
s[i] = code(s[i], true, a64, a256, 64, 256);
}
return s.join('');
};
return obj;
}]);