/*
 * Conditions Of Use
 *
 * This software was developed by employees of the National Institute of
 * Standards and Technology (NIST), an agency of the Federal Government.
 * Pursuant to title 15 Untied States Code Section 105, works of NIST
 * employees are not subject to copyright protection in the United States
 * and are considered to be in the public domain.  As a result, a formal
 * license is not needed to use the software.
 *
 * This software is provided by NIST as a service and is expressly
 * provided "AS IS."  NIST MAKES NO WARRANTY OF ANY KIND, EXPRESS, IMPLIED
 * OR STATUTORY, INCLUDING, WITHOUT LIMITATION, THE IMPLIED WARRANTY OF
 * MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE, NON-INFRINGEMENT
 * AND DATA ACCURACY.  NIST does not warrant or make any representations
 * regarding the use of the software or the results thereof, including but
 * not limited to the correctness, accuracy, reliability or usefulness of
 * the software.
 *
 * Permission to use this software is contingent upon your acceptance
 * of the terms of this agreement
 *
 * .
 *
 */
/*******************************************************************************
 * Product of NIST/ITL Advanced Networking Technologies Division (ANTD).       *
 *******************************************************************************/
package gov.nist.javax.sip.header;

import gov.nist.core.HostPort;
import gov.nist.javax.sip.address.AddressImpl;
import gov.nist.javax.sip.parser.Parser;

import javax.sip.header.ToHeader;
import java.text.ParseException;

/**
 * To SIP Header.
 *
 * @version 1.2 $Revision: 1.11 $ $Date: 2009/07/17 18:57:39 $
 *
 * @author M. Ranganathan <br/>
 * @author Olivier Deruelle <br/>
 *
 *
 *
 */

public final class To extends AddressParametersHeader implements
        javax.sip.header.ToHeader {

    /**
     * Comment for <code>serialVersionUID</code>
     */
    private static final long serialVersionUID = -4057413800584586316L;

    /**
     * default Constructor.
     */
    public To() {
        super(TO,true);
    }

    /**
     * Generate a TO header from a FROM header
     */
    public To(From from) {
        super(TO);
        setAddress(from.address);
        setParameters(from.parameters);
    }

    /**
     * Encode the header into a String.
     *
     * @since 1.0
     * @return String
     */
    public String encode() {
        return headerName + COLON + SP + encodeBody() + NEWLINE;
    }

    /**
     * Encode the header content into a String.
     *
     * @return String
     */
    protected String encodeBody() {
        return encodeBody(new StringBuffer()).toString();
    }

    protected StringBuffer encodeBody(StringBuffer buffer) {
        if (address != null) {
            if (address.getAddressType() == AddressImpl.ADDRESS_SPEC) {
                buffer.append(LESS_THAN);
            }
            address.encode(buffer);
            if (address.getAddressType() == AddressImpl.ADDRESS_SPEC) {
                buffer.append(GREATER_THAN);
            }

            if (!parameters.isEmpty()) {
                buffer.append(SEMICOLON);
                parameters.encode(buffer);
            }
        }
        return buffer;
    }

    /**
     * Conveniance accessor function to get the hostPort field from the address.
     * Warning -- this assumes that the embedded URI is a SipURL.
     *
     * @return hostport field
     */
    public HostPort getHostPort() {
        if (address == null)
            return null;
        return address.getHostPort();
    }

    /**
     * Get the display name from the address.
     *
     * @return Display name
     */
    public String getDisplayName() {
        if (address == null)
            return null;
        return address.getDisplayName();
    }

    /**
     * Get the tag parameter from the address parm list.
     *
     * @return tag field
     */
    public String getTag() {
        if (parameters == null)
            return null;
        return getParameter(ParameterNames.TAG);

    }

    /**
     * Boolean function
     *
     * @return true if the Tag exist
     */
    public boolean hasTag() {
        if (parameters == null)
            return false;
        return hasParameter(ParameterNames.TAG);

    }

    /**
     * remove Tag member
     */
    public void removeTag() {
            if (parameters != null)
                parameters.delete(ParameterNames.TAG);

    }

    /**
     * Set the tag member. This should remain empty for the initial request in
     * a dialog.
     *
     * @param t - tag String to set.
     */
    public void setTag(String t) throws ParseException {
        // JvB: check that it is a valid token
        Parser.checkToken(t);
        this.setParameter(ParameterNames.TAG, t);
    }

    /**
     * Get the user@host port string.
     */
    public String getUserAtHostPort() {
        if (address == null)
            return null;
        return address.getUserAtHostPort();
    }

    public boolean equals(Object other) {
        return (other instanceof ToHeader) && super.equals(other);
    }
}