STUN Client

��using System;

using System.Collections.Generic;

using System.Text;



namespace LumiSoft.Net.SDP

{

    /// <summary>

    /// Session Description Protocol. Defined in RFC 4566.

    /// </summary>

    public class SDP

    {

        private string              m_Version            = "0";

        private string              m_Origin             = "";

        private string              m_SessionName        = "";

        private string              m_SessionDescription = "";

        private string              m_Uri                = "";

        private SDP_ConnectionData  m_pConnectionData    = null;

        private List<SDP_Time>      m_pTimes             = null;

        private string              m_RepeatTimes        = "";

        private List<SDP_Attribute> m_pAttributes        = null;

        private List<SDP_Media>     m_pMedias            = null;



        /// <summary>

        /// Default constructor.

        /// </summary>

        public SDP()

        {

            m_pTimes      = new List<SDP_Time>();

            m_pAttributes = new List<SDP_Attribute>();

            m_pMedias     = new List<SDP_Media>();

        }





        #region method Parse



        /// <summary>

        /// Parses SDP from raw data.

        /// </summary>

        /// <param name="data">Raw SDP data.</param>

        public static SDP Parse(string data)

        {

            if(data == null){

                throw new ArgumentNullException("data");

            }



            SDP sdp = new SDP();



            System.IO.StringReader r = new System.IO.StringReader(data);



            string line = r.ReadLine();



            //--- Read global fields ---------------------------------------------       

            while(line != null){

                line = line.Trim();



                // We reached to media descriptions

                if(line.ToLower().StartsWith("m")){

                    /*

                        m=  (media name and transport address)

                        i=* (media title)

                        c=* (connection information -- optional if included at session level)

                        b=* (zero or more bandwidth information lines)

                        k=* (encryption key)

                        a=* (zero or more media attribute lines)

                    */



                    SDP_Media media = new SDP_Media();

                    media.MediaDescription = SDP_MediaDescription.Parse(line);

                    sdp.Media.Add(media);

                    line = r.ReadLine();

                    // Pasrse media fields and attributes

                    while(line != null){

                        line = line.Trim();



                        // Next media descrition, just stop active media description parsing, 

                        // fall through main while, allow next while loop to process it.

                        if(line.ToLower().StartsWith("m")){

                            break;

                        }

                        // i media title

                        else if(line.ToLower().StartsWith("i")){

                            media.Title = line.Split(new char[]{'='},2)[1].Trim();

                        }

                        // c connection information

                        else if(line.ToLower().StartsWith("c")){

                            media.ConnectionData = SDP_ConnectionData.Parse(line);

                        }

                        // a Attributes

                        else if(line.ToLower().StartsWith("a")){

                            media.Attributes.Add(SDP_Attribute.Parse(line));

                        }



                        line = r.ReadLine();

                    }

                    break;

                }

                // v Protocol Version

                else if(line.ToLower().StartsWith("v")){

                    sdp.Version = line.Split(new char[]{'='},2)[1].Trim();

                }

                // o Origin

                else if(line.ToLower().StartsWith("o")){

                    sdp.Originator = line.Split(new char[]{'='},2)[1].Trim();

                }

                // s Session Name

                else if(line.ToLower().StartsWith("s")){

                    sdp.SessionName = line.Split(new char[]{'='},2)[1].Trim();

                }

                // i Session Information

                else if(line.ToLower().StartsWith("i")){

                    sdp.SessionDescription = line.Split(new char[]{'='},2)[1].Trim();

                }

                // u URI

                else if(line.ToLower().StartsWith("u")){

                    sdp.Uri = line.Split(new char[]{'='},2)[1].Trim();

                }

                // c Connection Data

                else if(line.ToLower().StartsWith("c")){

                    sdp.ConnectionData = SDP_ConnectionData.Parse(line);

                }

                // t Timing

                else if(line.ToLower().StartsWith("t")){

                    sdp.Times.Add(SDP_Time.Parse(line));

                }

                // a Attributes

                else if(line.ToLower().StartsWith("a")){

                    sdp.Attributes.Add(SDP_Attribute.Parse(line));

                }



                line = r.ReadLine().Trim();

            }



            return sdp;

        }



        #endregion





        #region mehtod ToFile



        /// <summary>

        /// Stores SDP data to specified file. Note: official suggested file extention is .sdp.

        /// </summary>

        /// <param name="fileName">File name with path where to store SDP data.</param>

        public void ToFile(string fileName)

        {

            System.IO.File.WriteAllText(fileName,this.ToStringData());

        }



        #endregion



        #region method ToStringData



        /// <summary>

        /// Returns SDP as string data.

        /// </summary>

        /// <returns></returns>

        public string ToStringData()

        {

            StringBuilder retVal = new StringBuilder();



            // v Protocol Version

            retVal.AppendLine("v=" + this.Version);

            // o Origin

            if(!string.IsNullOrEmpty(this.Originator)){

                retVal.AppendLine("0=" + this.Originator);

            }

            // s Session Name

            if(!string.IsNullOrEmpty(this.SessionName)){

                retVal.AppendLine("s=" + this.SessionName);

            }

            // i Session Information

            if(!string.IsNullOrEmpty(this.SessionDescription)){

                retVal.AppendLine("i=" + this.SessionDescription);

            }

            // u URI

            if(!string.IsNullOrEmpty(this.Uri)){

                retVal.AppendLine("u=" + this.Uri);

            }

            // c Connection Data

            if(this.ConnectionData != null){

                retVal.Append(this.ConnectionData.ToValue());

            }

            // t Timing

            foreach(SDP_Time time in this.Times){

                retVal.Append(time.ToValue());

            }

            // a Attributes

            foreach(SDP_Attribute attribute in this.Attributes){

                retVal.Append(attribute.ToValue());

            }

            // m media description(s)

            foreach(SDP_Media media in this.Media){

                retVal.Append(media.ToValue());

            }



            return retVal.ToString();

        }



        #endregion





        #region Properties Impelementation



        /// <summary>

        /// Gets or sets version of the Session Description Protocol.

        /// </summary>

        public string Version

        {

            get{ return m_Version; }



            set{

                if(string.IsNullOrEmpty(value)){

                    throw new ArgumentException("Property Version can't be null or empty !");

                }



                m_Version = value;

            }

        }



        /// <summary>

        /// Gets originator and session identifier.

        /// </summary>

        public string Originator

        {

            get{ return m_Origin; }



            set{

                m_Origin = value;

            }

        }



        /// <summary>

        /// Gets or sets textual session name.

        /// </summary>

        public string SessionName

        {

            get{ return m_SessionName; }



            set{

                if(string.IsNullOrEmpty(value)){

                    throw new ArgumentException("Property SessionName can't be null or empty !");

                }



                m_SessionName = value;

            }

        }



        /// <summary>

        /// Gets or sets textual information about the session. This is optional value, null means not specified.

        /// </summary>

        public string SessionDescription

        {

            get{ return m_SessionDescription; }



            set{ m_SessionDescription = value; }

        }



        /// <summary>

        /// Gets or sets Uniform Resource Identifier. The URI should be a pointer to additional information 

        /// about the session. This is optional value, null means not specified.

        /// </summary>

        public string Uri

        {

            get{ return m_Uri; }



            set{ m_Uri = value; }

        }



        /// <summary>

        /// Gets or sets connection data. This is optional value if each media part specifies this value,

        /// null means not specified.

        /// </summary>

        public SDP_ConnectionData ConnectionData

        {

            get{ return m_pConnectionData; }



            set{

                m_pConnectionData = value;

            }

        }



        /// <summary>

        /// Gets start and stop times for a session. If Count = 0, t field not written dot SDP data.

        /// </summary>

        public List<SDP_Time> Times

        {

            get{ return m_pTimes; }

        }



        /// <summary>

        /// Gets or sets repeat times for a session. This is optional value, null means not specified.

        /// </summary>

        public string RepeatTimes

        {

            get{ return m_RepeatTimes; }



            set{ m_RepeatTimes = value; }

        }



        /// <summary>

        /// Gets attributes collection. This is optional value, Count == 0 means not specified.

        /// </summary>

        public List<SDP_Attribute> Attributes

        {

            get{ return m_pAttributes; }

        }



        /// <summary>

        /// Gets media parts collection.

        /// </summary>

        public List<SDP_Media> Media

        {

            get{ return m_pMedias; }

        }



        #endregion



    }

}