// This Source Code is in the Public Domain per: http://unlicense.org
package org.litesoft.peertopeer.nonpublic.peermanagement;

import java.io.*;
import java.net.*;

/**
 * Handle They Contacted Us
 * <p/>
 * wait for 1st message, if approriate, handle, and start Peering...:
 */
public class PeerConnectionHandlerTheyContactedUs extends PeerConnectionHandler
{
    public PeerConnectionHandlerTheyContactedUs( PeerConnectionManager pConnectionManager, Socket pSocket )
    {
        super( pConnectionManager, null, pSocket );
    }

    /**
     * Handle They Contacted Us
     * <p/>
     * Open both streams,
     * wait for 1st message, either:
     * <p/>
     * CantPeerDifferentGroupVersion w/
     * Our Name/ID & Supported Group Protocol Version
     * or
     * PeerList (possibly empty) of all 'other' known Group Peers.
     * <p/>
     * If was CantPeerDifferentGroupVersion, then we:
     * <p/>
     * Close the connection,
     * and either:
     * <p/>
     * Proceeds as if we were never contacted.
     * or
     * Shuts down as mixed versions are unacceptable!
     * <p/>
     * If was PeerList, then we:
     * <p/>
     */
    @Override
    protected void LLrun()
            throws IOException, ClassNotFoundException
    {
        Serializable zSerializable = LLread();
        if ( zSerializable instanceof PeerList )
        {
            handle( (PeerList) zSerializable );
        }
        else if ( zSerializable instanceof CantPeerDifferentGroupVersion )
        {
            handle( (CantPeerDifferentGroupVersion) zSerializable );
        }
        else
        {
            LOGGER.error.log( "Unexpected 1st message: " + zSerializable );
        }
        // otherwise simply return, which will shut down the connection...
    }

    /**
     * Close the connection,
     * and either:
     * <p/>
     * Proceeds as if we were never contacted.
     * or
     * Shuts down as mixed versions are unacceptable!
     */
    private void handle( CantPeerDifferentGroupVersion pCantPeerDifferentGroupVersion )
            throws IOException, ClassNotFoundException
    {
        if ( !isOKtoRunIfIncompatibleVersionAlreadyRunning() )
        {
            Error zError = new Error( pCantPeerDifferentGroupVersion.toString() );
            LOGGER.error.log( zError );
            zError.printStackTrace();
            System.exit( 1 );
        }
        // otherwise return and close connection and continue running normally...
    }

    /**
     * Wire into ConnectionManager as Regular Peer
     * And for each Peer in the List just recieved that is currently unknown,
     * it is added to the Contact Pending List and treated as an Announced Peer.
     */
    private void handle( PeerList pPeerList )
            throws IOException, ClassNotFoundException
    {
        setPeerDef( pPeerList );
        if ( startPeering() )
        {
            notifyConnectionManagerOf( pPeerList.getPeers() );
            runAsSenderThread();
        }
    }
}