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path: root/view/poc/util/base64-binary.js
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var Base64Binary = {
    _keyStr : "ABCDEFGHIJKLMNOPQRSTUVWXYZabcdefghijklmnopqrstuvwxyz0123456789+/=",
	
	/* will return a  Uint8Array type */
	decodeArrayBuffer: function(input) {
		var bytes = (input.length/4) * 3;
		var ab = new ArrayBuffer(bytes);
		this.decode(input, ab);
		
		return ab;
	},
	
	decode: function(input, arrayBuffer) {
		//get last chars to see if are valid
		var lkey1 = this._keyStr.indexOf(input.charAt(input.length-1));		 
		var lkey2 = this._keyStr.indexOf(input.charAt(input.length-2));		 
	
		var bytes = (input.length/4) * 3;
		if (lkey1 == 64) bytes--; //padding chars, so skip
		if (lkey2 == 64) bytes--; //padding chars, so skip
		
		var uarray;
		var chr1, chr2, chr3;
		var enc1, enc2, enc3, enc4;
		var i = 0;
		var j = 0;
		
		if (arrayBuffer)
			uarray = new Uint8Array(arrayBuffer);
		else
			uarray = new Uint8Array(bytes);
		
		input = input.replace(/[^A-Za-z0-9\+\/\=]/g, "");
		
		for (i=0; i<bytes; i+=3) {	
			//get the 3 octects in 4 ascii chars
			enc1 = this._keyStr.indexOf(input.charAt(j++));
			enc2 = this._keyStr.indexOf(input.charAt(j++));
			enc3 = this._keyStr.indexOf(input.charAt(j++));
			enc4 = this._keyStr.indexOf(input.charAt(j++));
	
			chr1 = (enc1 << 2) | (enc2 >> 4);
			chr2 = ((enc2 & 15) << 4) | (enc3 >> 2);
			chr3 = ((enc3 & 3) << 6) | enc4;
	
			uarray[i] = chr1;			
			if (enc3 != 64) uarray[i+1] = chr2;
			if (enc4 != 64) uarray[i+2] = chr3;
		}
	
		return uarray;	
	}
}