/**
 *
 * Licensed Materials - Property of IBM
 * IBM Cognos Products: ccl4j
 * (C) Copyright IBM Corp. 2009, 2010
 * US Government Users Restricted Rights – Use, duplication or disclosure restricted 
 * by GSA ADP Schedule Contract with IBM Corp.
 *
 */

/**
 * A Javascript file that provides a set of functions to retrieve the parameters of the cam passport cookie. A web64 encoded
 * value is expected.
 * 
 * Functions provided:
 * 		canCurrentUserCallLogon
 * 		getPassportGeneration
 * 		getPassportID
 * 		getVersion
 * 		isLoggingEnabled
 * 		isCamConfiguredForAnonymous
 * 		isCurrentUserAnonymous
 * 		areCamNamespacesConfigured
 * 
 */

var web64EncodedChars = "ABCDEFGHIJKLMNOPQRSTUVWXYZabcdefghijklmnopqrstuvwxyz0123456789*-";
var web64PadChar = '_';

// delimiter for fields in the cookie.
var DELIMITER = ";";

// indicates that a feature is enabled.
var FLAG_SET = "1";

var PID_HEADER_SIZE = 4;
var PID_HEADER_NAMESPACES_CONFIGURED_FLAG_START = 0;
var PID_HEADER_NAMESPACES_CONFIGURED_FLAG_END = 1;
var PID_HEADER_ANONYMOUS_CONFIGURED_FLAG_START = 1;
var PID_HEADER_ANONYMOUS_CONFIGURED_FLAG_END = 2;
var PID_HEADER_NAMED_USER_FLAG_START = 2;
var PID_HEADER_NAMED_USER_FLAG_END = 3;

// The cookie can have 2 formats.
// The new format is:
// version;passportID;loggingEnabled;passportGeneration;canUserCallLogon;
// i.e.
// 1;010:d1c8943e-0cf8-94f4-a5dc-a052647fc099:0231092414;0;3;0;
// The old format is:
// passportID
// i.e. 010:d1c8943e-0cf8-94f4-a5dc-a052647fc099:0231092414

function web64Decode(text)
{
	if(text == null || text.length == 0 || text.length % 4 != 0)
		return text;
	
	//web64 Decoding. Note: Does currently not support UTF8, or charCodeAt() values above 255.
	//Initialize the decode object based on the encode string.
	var decodeChars = {};
	for (var i=0; i<64; i++)
	{
		decodeChars[web64EncodedChars.charAt(i)] = i;
	}
	decodeChars[web64PadChar] = 64;

	var decodedString = "";
	var sourceLength = text.length;
	for (var i=0; i<sourceLength; i+=4)
	{
		//Get the next 4 characters. The last two characters could be padding characters, which will have a value of 64. 
		var charValue1 = decodeChars[text.charAt(i)];
		var charValue2 = decodeChars[text.charAt(i+1)];
		var charValue3 = decodeChars[text.charAt(i+2)];
		var charValue4 = decodeChars[text.charAt(i+3)];

		decodedString += String.fromCharCode((charValue1 << 2) + (charValue2 >> 4));
		charValue2 = (charValue2 & 15) << 4;
		if (charValue3 != 64)
		{
			decodedString += String.fromCharCode(charValue2 + (charValue3 >> 2));
			charValue3 = (charValue3 & 3) << 6;
			if (charValue4 != 64)
			{
				decodedString += String.fromCharCode(charValue3 + charValue4);
			}
		}
	}
	return decodedString;
}

function parse(camPassportCookie)
{
	// set defaults
	var cookieObj = new Object();
	cookieObj.version = 0;
	cookieObj.passportId = null;
	cookieObj.loggingEnabled = true;
	cookieObj.passportGeneration = 0;
	cookieObj.canUserCallLogon = true;
	
	var values = new Array();
	
	try
	{
		if (camPassportCookie != null && camPassportCookie.length > 0)
		{
			if (camPassportCookie.charAt(3) == ':')
			{
				// old format
				cookieObj.passportId = camPassportCookie;
				cookieObj.passportGeneration = 1;
			}
			else
			{
				// get version
				var startPos = 0;
				var endPos = camPassportCookie.indexOf(DELIMITER, startPos);
				if(endPos == -1)
					throw "";
				values[0] = camPassportCookie.substring(startPos, endPos);
				
				startPos = endPos + 1;
				
				// get passportId
				endPos = camPassportCookie.indexOf(DELIMITER, startPos);
				if(endPos == -1)
					throw "";
				values[1] = camPassportCookie.substring(startPos, endPos);
				
				startPos = endPos + 1;
				
				// get loggingEnabled
				endPos = camPassportCookie.indexOf(DELIMITER, startPos);
				if(endPos == -1)
					throw "";
				values[2] = camPassportCookie.substring(startPos, endPos);
				
				startPos = endPos + 1;
				
				// get passportGeneration
				endPos = camPassportCookie.indexOf(DELIMITER, startPos);
				if(endPos == -1)
					throw "";
				values[3] = camPassportCookie.substring(startPos, endPos);
				
				startPos = endPos + 1;
				
				// get canUserCallLogon
				endPos = camPassportCookie.indexOf(DELIMITER, startPos);
				if(endPos == -1)
					throw "";
				values[4] = camPassportCookie.substring(startPos, endPos);
			}

		}
	}
	catch(err)
	{
	}
	
	if (values.length == 5)
	{
		// cam passport cookie is valid, copy the values
		cookieObj.version = values[0];
		cookieObj.passportId = values[1];
		cookieObj.loggingEnabled = values[2];
		cookieObj.passportGeneration = values[3];
		cookieObj.canUserCallLogon = values[4];
	}
	
	return cookieObj;
}

function canCurrentUserCallLogon(/* web64 encoded string */ camPassportCookie)
{
	var decodedValue = web64Decode(camPassportCookie);

	if (parse(decodedValue).canUserCallLogon == FLAG_SET)
		return true;
	else
		return false;
}

function getPassportGeneration(/* web64 encoded string */ camPassportCookie)
{
	var decodedValue = web64Decode(camPassportCookie);
	return parse(decodedValue).passportGeneration;
}

function getPassportID(/* web64 encoded string */ camPassportCookie)
{
	var decodedValue = web64Decode(camPassportCookie);
	return parse(decodedValue).passportId;
}

function getVersion(/* web64 encoded string */ camPassportCookie)
{
	var decodedValue = web64Decode(camPassportCookie);
	return parse(decodedValue).version;
}

function isLoggingEnabled(/* web64 encoded string */ camPassportCookie)
{
	var decodedValue = web64Decode(camPassportCookie);

	if (parse(decodedValue).loggingEnabled == FLAG_SET)
		return true;
	else
		return false;
}

function isCamConfiguredForAnonymous(/* web64 encoded string */ camPassportCookie)
{
	var decodedValue = web64Decode(camPassportCookie);
	var passportId = parse(decodedValue).passportId;

	if (passportId != null && passportId.length > PID_HEADER_SIZE)
	{
		var flagBit =
				passportId.substring(PID_HEADER_ANONYMOUS_CONFIGURED_FLAG_START, PID_HEADER_ANONYMOUS_CONFIGURED_FLAG_END);
		if (flagBit == FLAG_SET)
			return true;
	}
	
	return false;
}

function isCurrentUserAnonymous(/* web64 encoded string */ camPassportCookie)
{
	var decodedValue = web64Decode(camPassportCookie);
	var passportId = parse(decodedValue).passportId;

	if (passportId != null && passportId.length > PID_HEADER_SIZE)
	{
		var flagBit = passportId.substring(PID_HEADER_NAMED_USER_FLAG_START, PID_HEADER_NAMED_USER_FLAG_END);
		if (flagBit == FLAG_SET)
			return false;
		else
			return true;
	}
	
	return false;
}

function areCamNamespacesConfigured(/* web64 encoded string */ camPassportCookie)
{
	var decodedValue = web64Decode(camPassportCookie);
	var passportId = parse(decodedValue).passportId;

	if (passportId != null && passportId.length > PID_HEADER_SIZE)
	{
		var flagBit =
				passportId.substring(PID_HEADER_NAMESPACES_CONFIGURED_FLAG_START, PID_HEADER_NAMESPACES_CONFIGURED_FLAG_END);
		if (flagBit == FLAG_SET)
			return true;
	}
	return false;
}