/*
 * Copyright (C) 2005 Luca Veltri - University of Parma - Italy
 * Copyright (C) 2010 The Sipdroid Open Source Project
 * 
 * This file is part of MjSip (http://www.mjsip.org)
 * 
 * MjSip is free software; you can redistribute it and/or modify
 * it under the terms of the GNU General Public License as published by
 * the Free Software Foundation; either version 2 of the License, or
 * (at your option) any later version.
 * 
 * MjSip is distributed in the hope that it will be useful,
 * but WITHOUT ANY WARRANTY; without even the implied warranty of
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
 * GNU General Public License for more details.
 * 
 * You should have received a copy of the GNU General Public License
 * along with MjSip; if not, write to the Free Software
 * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA
 * 
 * Author(s):
 * Luca Veltri (luca.veltri@unipr.it)
 * Nitin Khanna, Hughes Systique Corp. (Reason: Android specific change, optmization, bug fix) 
 */

package org.zoolu.sdp;

import java.util.Vector;

/**
 * Class MediaDescriptor handles SDP media descpriptions.
 * <p>
 * A MediaDescriptor can be part of a SessionDescriptor, and contains details
 * that apply onto to a single media stream.
 * <p>
 * A single SessionDescriptor may convey zero or more MediaDescriptors.
 * <p>
 * In the current implementation, the MediaDescriptor consists of the m (media)
 * and c (connection information) fields, followed by zero or more a (attribute)
 * fields. The m field is mandatory for a MediaDescriptor.
 */
public class MediaDescriptor {
	/** Media field ('m'). */
	MediaField m;
	/** Connection field ('c') */
	ConnectionField c;
	/** Vector of attribute fileds ('a') */
	/* HSC CHANGE STARTS */
	Vector<AttributeField> av;

	/* HSC CHANGE ENDS */

	/**
	 * Creates a new MediaDescriptor.
	 * 
	 * @param md
	 *            the cloned MediaDescriptor
	 */
	public MediaDescriptor(MediaDescriptor md) {
		m = new MediaField(md.m);
		if (md.c != null)
			c = new ConnectionField(md.c);
		else
			c = null;
		/* HSC CHANGE STARTS */
		av = new Vector<AttributeField>();
		/* HSC CHANGE ENDS */
		for (int i = 0; i < md.av.size(); i++) {
			av.addElement(new AttributeField((AttributeField) md.av
					.elementAt(i)));
		}
	}

	/**
	 * Creates a new MediaDescriptor with m <i>media</i> and c <i>connection</i>.
	 * No attribute is set by default.
	 * 
	 * @param media
	 *            the MediaField
	 * @param connection
	 *            the ConnectionField, or null if no ConnectionField is present
	 *            in the MediaDescriptor
	 */
	public MediaDescriptor(MediaField media, ConnectionField connection) {
		m = media;
		c = connection;
		/* HSC CHANGE BEGINS */
		av = new Vector<AttributeField>();
		/* HSC CHANGE ENDS */
	}

	/**
	 * Creates a new MediaDescriptor with m <i>media</i>, c <i>connection</i>,
	 * and a <i>attribute</i>.
	 * 
	 * @param media
	 *            the MediaField
	 * @param connection
	 *            the ConnectionField, or null if no ConnectionField is present
	 *            in the MediaDescriptor
	 * @param attribute
	 *            the first AttributeField
	 */
	public MediaDescriptor(MediaField media, ConnectionField connection,
			AttributeField attribute) {
		m = media;
		c = connection;
		/* HSC CHANGE BEGINS */
		av = new Vector<AttributeField>();
		/* HSC CHANGE ENDS */
		if (attribute != null)
			av.addElement(attribute);
	}

	/**
	 * Creates a new MediaDescriptor with m=<i>media</i> and c=<i>connection</i>,
	 * with attributes 'a' equals to <i>attributes</i> (Vector of
	 * AttributeField).
	 * 
	 * @param media
	 *            the MediaField
	 * @param connection
	 *            the ConnectionField, or null if no ConnectionField is present
	 *            in the MediaDescriptor
	 * @param attributes
	 *            the Vector of AttributeField
	 */
	/* HSC CHANGE BEGINS */
	public MediaDescriptor(MediaField media, ConnectionField connection,
			Vector<AttributeField> attributes) {
		m = media;
		c = connection;
		av = new Vector<AttributeField>(attributes.size());
		av.setSize(attributes.size());
		for (int i = 0; i < attributes.size(); i++)
			av.setElementAt((AttributeField) attributes.elementAt(i), i);
	}

	/* HSC CHANGE ENDS */

	/**
	 * Creates a new MediaDescriptor with m <i>media</i>, c <i>connection</i>,
	 * and a <i>attribute</i>.
	 * 
	 * @param media
	 *            the media field vaule
	 * @param connection
	 *            the connection field vaule, or null if no connection field is
	 *            present in the MediaDescriptor
	 * @param attribute
	 *            the first media attribute alue
	 */
	public MediaDescriptor(String media, String connection, String attribute) {
		m = new MediaField(media);
		if (connection != null)
			c = new ConnectionField(connection);
		/* HSC CHANGE BEGINS */
		av = new Vector<AttributeField>();
		/* HSC CHANGE ENDS */
		if (attribute != null)
			av.addElement(new AttributeField(attribute));
	}

	/**
	 * Creates a new MediaDescriptor from String <i>str</i>.
	 * 
	 * @param str
	 *            the media field line
	 */
	/*
	 * public MediaDescriptor(String str) { SdpParser par=new SdpParser(str);
	 * m=par.parseMediaField(); c=par.parseConnectionField(); av=new Vector();
	 * AttributeField a=par.parseAttributeField(); while (a!=null) {
	 * av.addElement(a); a=par.parseAttributeField(); } }
	 */

	/**
	 * Gets media.
	 * 
	 * @return the MediaField
	 */
	public MediaField getMedia() {
		return m;
	}

	/**
	 * Gets connection information.
	 * 
	 * @return the ConnectionField
	 */
	public ConnectionField getConnection() {
		return c;
	}

	/**
	 * Gets a Vector of attribute values.
	 * 
	 * @return a Vector of AttributeField
	 */
	/* HSC CHANGE BEGINS */
	public Vector<AttributeField> getAttributes() {
		Vector<AttributeField> v = new Vector<AttributeField>(av.size());
		/* HSC CHANGE ENDS */
		for (int i = 0; i < av.size(); i++)
			v.addElement((AttributeField) av.elementAt(i));
		return v;
	}

	/**
	 * Adds a new attribute
	 * 
	 * @param attribute
	 *            the new AttributeField
	 * @return this MediaDescriptor
	 */
	public MediaDescriptor addAttribute(AttributeField attribute) {
		av.addElement(new AttributeField(attribute));
		return this;
	}

	/**
	 * Whether it has a particular attribute
	 * 
	 * @param a_name
	 *            the attribute name
	 * @return true if found, otherwise returns null
	 */
	public boolean hasAttribute(String a_name) {
		for (int i = 0; i < av.size(); i++) {
			if (((AttributeField) av.elementAt(i)).getAttributeName().equals(
					a_name))
				return true;
		}
		return false;
	}

	/**
	 * Gets a particular attribute
	 * 
	 * @param a_name
	 *            the attribute name
	 * @return the AttributeField, or null if not found
	 */
	public AttributeField getAttribute(String a_name) {
		for (int i = 0; i < av.size(); i++) {
			AttributeField a = (AttributeField) av.elementAt(i);
			if (a.getAttributeName().equals(a_name))
				return a;
		}
		return null;
	}

	/**
	 * Gets a Vector of attribute values of a particular attribute name.
	 * 
	 * @param a_name
	 *            the attribute name
	 * @return a Vector of AttributeFields
	 */
	/* HSC CHANGE BEGINS */
	public Vector<AttributeField> getAttributes(String a_name) {
		Vector<AttributeField> v = new Vector<AttributeField>(av.size());
		/* HSC CHANGE ENDS */
		for (int i = 0; i < av.size(); i++) {
			AttributeField a = (AttributeField) av.elementAt(i);
			if (a.getAttributeName().equals(a_name))
				v.addElement(a);
		}
		return v;
	}

	/**
	 * Returns whether a particular codec is included in the media descriptor.
	 * 
	 * @param codec
	 *            the codec name (e.g. "GSM", "PCMA/8000")
	 * @return a String of the matched codec (e.g. "GSM/8000"), 
	 *         or null when the codec is not included.
	 */	
	public String hasCodec(String codec) {
		for (int i = 0; i < av.size(); i++) {
			AttributeField a = (AttributeField) av.elementAt(i);
			if (a.getAttributeName().equalsIgnoreCase("rtpmap")) {
				String[] ar = a.getAttributeValue().split(" +", 2);
				if (ar.length==2 && ar[1].toLowerCase().startsWith(codec.toLowerCase())) {
					return ar[1];
				}
			}
		}
		return null;
	}
	
	/**
	 * Gets a String rapresentation of the MediaDescriptor.
	 * 
	 * @return the string representation
	 */
	public String toString() {
		String str = "";
		str += m;
		if (c != null)
			str += c;
		for (int i = 0; i < av.size(); i++)
			str += (AttributeField) av.elementAt(i);
		return str;
	}

}
