/**
 * @author: Meki Cheraoui
 * See COPYING for copyright and distribution information.
 * This class represents Key Objects
 */

var Key = function Key(){
    /* TODO: Port from PyCCN:
	generateRSA()
	privateToDER()
	publicToDER()
	privateToPEM()
	publicToPEM()
	fromDER()
	fromPEM()
     */
}

/**
 * KeyLocator
 */
var KeyLocatorType = {
	KEY:1,
	CERTIFICATE:2,
	KEYNAME:3
};

var KeyLocator = function KeyLocator(_input,_type){ 

    this.type = _type;
    
    if (_type == KeyLocatorType.KEYNAME){
    	if (LOG>3) console.log('KeyLocator: SET KEYNAME');
    	this.keyName = _input;
    }
    else if (_type == KeyLocatorType.KEY){
    	if (LOG>3) console.log('KeyLocator: SET KEY');
    	this.publicKey = _input;
    }
    else if (_type == KeyLocatorType.CERTIFICATE){
    	if (LOG>3) console.log('KeyLocator: SET CERTIFICATE');
    	this.certificate = _input;
    }

};

KeyLocator.prototype.from_ccnb = function(decoder) {

	decoder.readStartElement(this.getElementLabel());

	if (decoder.peekStartElement(CCNProtocolDTags.Key)) {
		try {
			encodedKey = decoder.readBinaryElement(CCNProtocolDTags.Key);
			// This is a DER-encoded SubjectPublicKeyInfo.
			
			//TODO FIX THIS, This should create a Key Object instead of keeping bytes

			this.publicKey =   encodedKey;//CryptoUtil.getPublicKey(encodedKey);
			this.type = KeyLocatorType.KEY;
			

			if(LOG>4) console.log('PUBLIC KEY FOUND: '+ this.publicKey);
			//this.publicKey = encodedKey;
			
			
		} catch (e) {
			throw new Error("Cannot parse key: ", e);
		} 

		if (null == this.publicKey) {
			throw new Error("Cannot parse key: ");
		}

	} else if ( decoder.peekStartElement(CCNProtocolDTags.Certificate)) {
		try {
			encodedCert = decoder.readBinaryElement(CCNProtocolDTags.Certificate);
			
			/*
			 * Certificates not yet working
			 */
			
			//CertificateFactory factory = CertificateFactory.getInstance("X.509");
			//this.certificate = (X509Certificate) factory.generateCertificate(new ByteArrayInputStream(encodedCert));
			

			this.certificate = encodedCert;
			this.type = KeyLocatorType.CERTIFICATE;

			if(LOG>4) console.log('CERTIFICATE FOUND: '+ this.certificate);
			
		} catch ( e) {
			throw new Error("Cannot decode certificate: " +  e);
		}
		if (null == this.certificate) {
			throw new Error("Cannot parse certificate! ");
		}
	} else  {
		this.type = KeyLocatorType.KEYNAME;
		
		this.keyName = new KeyName();
		this.keyName.from_ccnb(decoder);
	}
	decoder.readEndElement();
};
	

KeyLocator.prototype.to_ccnb = function( encoder) {
	
	if(LOG>4) console.log('type is is ' + this.type);
	//TODO Check if Name is missing
	if (!this.validate()) {
		throw new ContentEncodingException("Cannot encode " + this.getClass().getName() + ": field values missing.");
	}

	
	//TODO FIX THIS TOO
	encoder.writeStartElement(this.getElementLabel());
	
	if (this.type == KeyLocatorType.KEY) {
		if(LOG>5)console.log('About to encode a public key' +this.publicKey);
		encoder.writeElement(CCNProtocolDTags.Key, this.publicKey);
		
	} else if (this.type == KeyLocatorType.CERTIFICATE) {
		
		try {
			encoder.writeElement(CCNProtocolDTags.Certificate, this.certificate);
		} catch ( e) {
			throw new Error("CertificateEncodingException attempting to write key locator: " + e);
		}
		
	} else if (this.type == KeyLocatorType.KEYNAME) {
		
		this.keyName.to_ccnb(encoder);
	}
	encoder.writeEndElement();
	
};

KeyLocator.prototype.getElementLabel = function() {
	return CCNProtocolDTags.KeyLocator; 
};

KeyLocator.prototype.validate = function() {
	return (  (null != this.keyName) || (null != this.publicKey) || (null != this.certificate)   );
};

/**
 * KeyName is only used by KeyLocator.
 */
var KeyName = function KeyName() {
	

	this.contentName = this.contentName;//contentName
	this.publisherID =this.publisherID;//publisherID

};

KeyName.prototype.from_ccnb=function( decoder){
	

	decoder.readStartElement(this.getElementLabel());

	this.contentName = new Name();
	this.contentName.from_ccnb(decoder);
	
	if(LOG>4) console.log('KEY NAME FOUND: ');
	
	if ( PublisherID.peek(decoder) ) {
		this.publisherID = new PublisherID();
		this.publisherID.from_ccnb(decoder);
	}
	
	decoder.readEndElement();
};

KeyName.prototype.to_ccnb = function( encoder) {
	if (!this.validate()) {
		throw new Error("Cannot encode : field values missing.");
	}
	
	encoder.writeStartElement(this.getElementLabel());
	
	this.contentName.to_ccnb(encoder);
	if (null != this.publisherID)
		this.publisherID.to_ccnb(encoder);

	encoder.writeEndElement();   		
};
	
KeyName.prototype.getElementLabel = function() { return CCNProtocolDTags.KeyName; };

KeyName.prototype.validate = function() {
		// DKS -- do we do recursive validation?
		// null signedInfo ok
		return (null != this.contentName);
};

KeyName.prototype.matches_name = function(/*Name*/ name) {
	var i_name = this.contentName.components;
	var o_name = name.components;

	// The intrest name is longer than the name we are checking it against.
	if (i_name.length > o_name.length)
            return false;

	// Check if at least one of given components doesn't match.
        for (var i = 0; i < i_name.length; ++i) {
            if (!DataUtils.arraysEqual(i_name[i], o_name[i]))
                return false;
        }

	return true;
}