// This Source Code is in the Public Domain per: http://litesoft.org/License.txt
package InterModuleComm;

import org.litesoft.util.*;

public final class WelcomeMessage implements Message
{
    protected static final String PREFIX =
            Constants.PROTOCOL_PREFIX + ModuleMsgLifecycleForm.Welcome + Constants.NV_SEP;

    private String mKnownAs;
    private String mId;

    protected WelcomeMessage( String pKnownAs, String pId )
    {
        mKnownAs = pKnownAs;
        mId = pId;
    }

    @Override
    public String toString()
    {
        return getHeader();
    }

    public String ToSendText()
    {
        return getHeader() + "\n";
    }

    public String getHeader()
    {
        return PREFIX + getKnownAs() + Constants.SPECIAL_ID_SEP + getId();
    }

    public String getKnownAs()
    {
        return mKnownAs;
    }

    public String getId()
    {
        return mId;
    }

    public static class Builder
    {
        private String mKnownAs;
        private String mId;

        public static Builder FromHeader( String pHeader )
        {
            if ( (pHeader != null) && pHeader.startsWith( PREFIX ) )
            {
                String zRest = Utils.trimLeadingSpaces( pHeader.substring( PREFIX.length() ) );
                int zSepAt = zRest.indexOf( Constants.SPECIAL_ID_SEP );
                if ( zSepAt != -1 )
                {
                    String zKnownAs = zRest.substring( 0, zSepAt ).trim();
                    String zId = zRest.substring( zSepAt + 1 ).trim();
                    return FromParams( zKnownAs, zId );
                }
            }
            return null;
        }

        private Builder( String pKnownAs, String pId )
        {
            mKnownAs = pKnownAs;
            mId = pId;
        }

        private static Builder FromParams( String pKnownAs, String pId )
        {
            pKnownAs = Utils.noEmpty( pKnownAs );
            pId = Utils.noEmpty( pId );
            if ( Utils.isAsciiIdentifier( pKnownAs ) && Utils.isNoSpaceAscii( pId ) )
            {
                return new Builder( pKnownAs, pId );
            }
            return null;
        }

        public static Builder Acknowledge( HelloMessage pHelloMessage, String pKnownAs )
        {
            pKnownAs = Utils.noEmpty( pKnownAs );
            if ( (pHelloMessage != null) && Utils.isAsciiIdentifier( pKnownAs ) )
            {
                return FromParams( pKnownAs, pHelloMessage.getId() );
            }
            return null;
        }

        public WelcomeMessage ToMsg()
        {
            return new WelcomeMessage( getKnownAs(), getId() );
        }

        public String getKnownAs()
        {
            return mKnownAs;
        }

        public String getId()
        {
            return mId;
        }
    }
}