forked from sheetjs/sheetjs
45 lines
1.3 KiB
TypeScript
45 lines
1.3 KiB
TypeScript
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var Base64 = (() => {
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var map = "ABCDEFGHIJKLMNOPQRSTUVWXYZabcdefghijklmnopqrstuvwxyz0123456789+/=";
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return {
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encode: function(input: string): string {
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var o = "";
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var c1=0, c2=0, c3=0, e1=0, e2=0, e3=0, e4=0;
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for(var i = 0; i < input.length; ) {
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c1 = input.charCodeAt(i++);
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e1 = (c1 >> 2);
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c2 = input.charCodeAt(i++);
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e2 = ((c1 & 3) << 4) | (c2 >> 4);
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c3 = input.charCodeAt(i++);
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e3 = ((c2 & 15) << 2) | (c3 >> 6);
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e4 = (c3 & 63);
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if (isNaN(c2)) { e3 = e4 = 64; }
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else if (isNaN(c3)) { e4 = 64; }
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o += map.charAt(e1) + map.charAt(e2) + map.charAt(e3) + map.charAt(e4);
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}
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return o;
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},
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decode: function(input: string): string {
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var o = "";
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var c1=0, c2=0, c3=0, e1=0, e2=0, e3=0, e4=0;
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input = input.replace(/[^\w\+\/\=]/g, "");
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for(var i = 0; i < input.length;) {
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e1 = map.indexOf(input.charAt(i++));
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e2 = map.indexOf(input.charAt(i++));
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c1 = (e1 << 2) | (e2 >> 4);
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o += String.fromCharCode(c1);
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e3 = map.indexOf(input.charAt(i++));
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c2 = ((e2 & 15) << 4) | (e3 >> 2);
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if (e3 !== 64) { o += String.fromCharCode(c2); }
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e4 = map.indexOf(input.charAt(i++));
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c3 = ((e3 & 3) << 6) | e4;
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if (e4 !== 64) { o += String.fromCharCode(c3); }
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}
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return o;
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}
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};
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})();
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