/*******************************************************************************
 *  Copyright 2017-2018 Centre for Development of Advanced Computing(C-DAC), Pune
 *  
 * Licensed under the Apache License, Version 2.0 (the "License");
 * you may not use this file except in compliance with the License.
 * You may obtain a copy of the License at
 *  
 *   http://www.apache.org/licenses/LICENSE-2.0
 *  
 * Unless required by applicable law or agreed to in writing, software
 * distributed under the License is distributed on an "AS IS" BASIS,
 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 * See the License for the specific language governing permissions and
 * limitations under the License.
 *******************************************************************************/
package cdac.medinfo.sdk.dcm30_04.baselibs;




import cdac.medinfo.sdk.dcm30_04.commoninterface.IDataElement;
import cdac.medinfo.sdk.dcm30_04.commoninterface.IDictionaryReader;
import cdac.medinfo.sdk.dcm30_04.commoninterface.ITag;
import cdac.medinfo.sdk.dcm30_04.commoninterface.ITransferSyntax;
import cdac.medinfo.sdk.dcm30_04.exceptions.InvalidItemException;
import cdac.medinfo.sdk.dcm30_04.exceptions.MandatoryMissingException;
import cdac.medinfo.sdk.dcm30_04.utils.DicomConfig;
import cdac.medinfo.sdk.dcm30_04.utils.DicomConstants;
import cdac.medinfo.sdk.dcm30_04.utils.DicomLogger;

import cdac.medinfo.sdk.dcm30_04.utils.ISingleCollection;


/**
 * A sequence of one or more items that describe the parameters used to calculate a
 * MAC for use in Digital Signatures.
 */
public class MACParametersSequenceItem extends Item  
{
	

	/**
	 * 
	 */
	private static final long serialVersionUID = 1L;

	/**
	 * This constructor creates the item and with default TransferSyntax 
	 */
	MACParametersSequenceItem()
	{
		super();
	}

	/*
	 * This constructor calls the respective superclass constructor
	 * This constructor should throw exception if null TS is tried to be set
	 */
	/**
	 * This constructor creates the item with default TransferSyntax.
	 * @param objTransferSyntax specifies the DICOM Standard defined TransfeSyntax. 
	 */
	MACParametersSequenceItem(ITransferSyntax objITransferSyntax)
	{
		super(objITransferSyntax);
	}

	/**
	 * This constructor creates Item with specified transferSyntax and specified DictionaryReader
	 * @param objTransferSyntax specifies the DICOM Standard defined TransfeSyntax
	 * @param objDictionaryReader specifies the DICOM Dictionary reader to be used 
	 */
	MACParametersSequenceItem(ITransferSyntax objTransferSyntax, IDictionaryReader objDictionaryReader)
	{
		super(objTransferSyntax,objDictionaryReader);
	}

	/**
	 * Sets a number used to identify this MAC Parameters Sequence item.
	 * @param shMACIDNumber short value of MAC ID Number.
	 */
	public void setMACIDNumber(short shMACIDNumber)
	{
		/*Accept the MAC ID Number in String format of type US.
		 * Read the Transfer Syntax and check if ImplicitDE or ExplicitDE to create
		 * 
		 * Set the iGroupNumber and iElementNumber to ImplicitDE object 
		 * Set the iVRType
		 * Set length from the element
		 * Add this element to the Data Set
		 */
		IDataElement objIDataElement = null;
		if(objITransferSyntax.getVRTransferSyntax() == DicomConstants.DCM_VR_IMPLICIT)
			objIDataElement = new ImplicitDE(0x0400, 0x0005, shMACIDNumber,getDictionaryReader());
		else
			objIDataElement = new ExplicitDE(0x0400, 0x0005,DicomConstants.DCM_DT_US, shMACIDNumber);

		addDataElement(objIDataElement);
	}

	/**
	 * Retrieves a number used to identify this MAC Parameters Sequence item.
	 * @return short - short value of MAC ID Number.
	 */
	public short getMACIDNumber()
	{
		Object objValue = getValue(0x0400, 0x0005);
		if(objValue != null)
			return Short.parseShort(objValue.toString());
		return DicomConstants.DCM_NO_VALUE;
	}

	/**
	 * Sets the Transfer Syntax UID used to encode the values of the Data Elements included in the
	 * MAC calculation.
	 * @param strMACCalculationTransferSyntaxUID String value of MAC Calculation Transfer Syntax UID.
	 */
	public void setMACCalculationTransferSyntaxUID(String strMACCalculationTransferSyntaxUID)
	{
		/*Accept the MAC Calculation Transfer Syntax UID in String format of type UI.
		 * Read the Transfer Syntax and check if ImplicitDE or ExplicitDE to create
		 * 
		 * Set the iGroupNumber and iElementNumber to ImplicitDE object 
		 * Set the iVRType
		 * Set length from the element
		 * Add this element to the Data Set
		 */
		IDataElement objIDataElement = null;
		if(objITransferSyntax.getVRTransferSyntax() == DicomConstants.DCM_VR_IMPLICIT)
			objIDataElement = new ImplicitDE(0x0400, 0x0010, strMACCalculationTransferSyntaxUID,getDictionaryReader());
		else
			objIDataElement = new ExplicitDE(0x0400, 0x0010,DicomConstants.DCM_DT_UI, strMACCalculationTransferSyntaxUID);

		addDataElement(objIDataElement);
	}

	/**
	 * Retrieves the Transfer Syntax UID used to encode the values of the Data Elements included in the
	 * MAC calculation.
	 * @return String - value of MAC Calculation Transfer Syntax UID.
	 */
	public String getMACCalculationTransferSyntaxUID()
	{
		Object objValue = getValue(0x0400, 0x0010);
		if(objValue != null)
			return objValue.toString();
		return null;
	}

	/**
	 * Sets the algorithm used in generating the MAC to be encrypted to form the Digital Signature.
	 * Defined Terms: RIPEMD160,MD5,SHA1.
	 * @param strMACAlgorithm String value of MAC Algorithm.
	 */
	public void setMACAlgorithm(String strMACAlgorithm)
	{
		/*Accept the MAC Algorithm in String format of type CS.
		 * Read the Transfer Syntax and check if ImplicitDE or ExplicitDE to create
		 * 
		 * Set the iGroupNumber and iElementNumber to ImplicitDE object 
		 * Set the iVRType
		 * Set length from the element
		 * Add this element to the Data Set
		 */
		IDataElement objIDataElement = null;
		if(objITransferSyntax.getVRTransferSyntax() == DicomConstants.DCM_VR_IMPLICIT)
			objIDataElement = new ImplicitDE(0x0400, 0x0015, strMACAlgorithm,getDictionaryReader());
		else
			objIDataElement = new ExplicitDE(0x0400, 0x0015,DicomConstants.DCM_DT_CS, strMACAlgorithm);

		addDataElement(objIDataElement);
	}

	/**
	 * Retrieves the algorithm used in generating the MAC to be encrypted to form the Digital Signature.
	 * @return String - value of MAC Algorithm.
	 */
	public String getMACAlgorithm()
	{
		Object objValue = getValue(0x0400, 0x0015);
		if(objValue != null)
			return objValue.toString();
		return null;
	}

	/**
	 * Sets a list of Data Element Tags in the order they appear in the Data Set which identify the Data
	 * Elements used in creating the MAC for the Digital Signature.
	 * @param objSingleCollection collction of Data Elements Signed.
	 */
	public void setDataElementsSigned(ISingleCollection<ITag> objSingleCollection)
	{
		/*Accept the Data Elements Signed in String format of type AT.
		 * Read the Transfer Syntax and check if ImplicitDE or ExplicitDE to create
		 * Set the iGroupNumber and iElementNumber to ImplicitDE object 
		 * Set the iVRType
		 * Set length from the element
		 * Add this element to the Data Set
		 */
		IDataElement objIDataElement = null;
		if(objITransferSyntax.getVRTransferSyntax() == DicomConstants.DCM_VR_IMPLICIT)
			objIDataElement = new ImplicitDE(0x0400, 0x0020, objSingleCollection,getDictionaryReader());
		else
			objIDataElement = new ExplicitDE(0x0400, 0x0020,DicomConstants.DCM_DT_AT, objSingleCollection);

		addDataElement(objIDataElement);
	}

	/**
	 * Retrieves a list of Data Element Tags in the order they appear in the Data Set which identify the Data
	 * Elements used in creating the MAC for the Digital Signature.
	 * @return ISingleCollection<ITag> - collection of Data Elements Signed.
	 */
	@SuppressWarnings("unchecked")
	public ISingleCollection<ITag> getDataElementsSigned()
	{
		Object objValue = getValue(0x0400, 0x0020);
		if(objValue != null)
			return (ISingleCollection<ITag>)objValue;
		return null;
	}

	/**
	 * Validates all the attributes in MAC Parameters Sequence Item that are present in the DataSet
	 * @return int - Success -true, Failure - false
	 * @throws InvalidItemException throws InvalidItemException If Mandatory or Conditional element fails.
	 */
	public boolean validateForModule()  throws InvalidItemException
	{
		try{
			if(!contains(0x0400,0x0005))
				throw new MandatoryMissingException("0400,0005");
			if(!contains(0x0400,0x0010))	
				throw new MandatoryMissingException("0400,0010");
			if(!contains(0x0400,0x0015))
				throw new MandatoryMissingException("0400,0015");
			if(!contains(0x0400,0x0020))	
				throw new MandatoryMissingException("0400,0020");
		}
		catch(MandatoryMissingException me)
		{
			if(DicomConfig.createInstance().isLoggingOn())
			{
				DicomLogger.getLogger().log(me.getMessage());
			}
			throw new InvalidItemException(this.getClass().getSimpleName(),me);
		}

		return true;
	}
}
