package edu.stanford.rt.credential;
import edu.stanford.rt.datatype.*;
/**
 * @author Ninghui Li, Sandra Qiu<br>
 *
 * This class handles <code>Principal</code> element, which consists of 
 * IntegerValue or StringValue.
 */
public class DataValuePrincipal extends Principal
{
	/**
	 * the principal value, which could be an integer or a string.
	 */
	private DataValue value;

	/**
	 * Constructor for DataValuePrincipal.
	 * 
	 *   Contruct a Principal object using a DataValue object. 
	 *   DomainSpecException  is thrown if value passed in is not an instance of
	 *   IntegerValue, StringValue, or KeyValue.
	 *   <br>
	 *   <code>IllegalArgumentException</code> is thrown if value
	 *   is not of <code>IntegerValue</code> or <code>StringValue</code> type.
	*/
	public DataValuePrincipal(DataValue value)
	{
		if (!(value instanceof IntegerValue)
			&& !(value instanceof StringValue))
			throw new IllegalArgumentException("Illegal argument");

		this.value = value;
	}
	/**
	 * Method getValue.
	 * @return DataValue
	 */
	public DataValue getValue()
	{
		return value;
	}
	/* (non-Javadoc)
	 * @see java.lang.Object#toString()
	 */
	public String toString()
	{
		return value.toString();
	}
	/* (non-Javadoc)
	 * @see java.lang.Object#hashCode()
	 */
	public int hashCode()
	{
		return value.hashCode();
	}
	/* (non-Javadoc)
	 * @see java.lang.Object#equals(Object)
	 */
	public boolean equals(Object value)
	{
		if (!(value instanceof IntegerValue)
			&& !(value instanceof StringValue))
			return false;
            
		if (value instanceof IntegerValue)
		{
			if (!(value instanceof IntegerValue))
				return false;
			else
				return this.hashCode() == value.hashCode();
		}
		else
		{
			if (!(value instanceof StringValue))
				return false;
			else
				return this.hashCode() == value.hashCode();
		}
	}

	/* (non-Javadoc)
	 * @see edu.stanford.rt.credential.PrincipalExpression#toString(String)
	 */
	public String toString(String indent)
	{
		String thisIndent = indent + "  ";
		return thisIndent + "DataValuePrincipal: " + value.toString();
	}
}