/*_############################################################################
  _## 
  _##  SNMP4J - ConnectionOrientedTransportMapping.java  
  _## 
  _##  Copyright (C) 2003-2026  Frank Fock (SNMP4J.org)
  _##  
  _##  Licensed under the Apache License, Version 2.0 (the "License");
  _##  you may not use this file except in compliance with the License.
  _##  You may obtain a copy of the License at
  _##  
  _##      http://www.apache.org/licenses/LICENSE-2.0
  _##  
  _##  Unless required by applicable law or agreed to in writing, software
  _##  distributed under the License is distributed on an "AS IS" BASIS,
  _##  WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
  _##  See the License for the specific language governing permissions and
  _##  limitations under the License.
  _##  
  _##########################################################################*/

package org.snmp4j.transport;

import org.snmp4j.*;
import org.snmp4j.smi.Address;
import org.snmp4j.util.CommonTimer;

import java.io.IOException;

/**
 * Transport mappings for connection oriented transport protocols have to
 * implement this interface.
 *
 * @author Frank Fock
 * @version 3.5.0
 * @since 1.7
 */
public interface ConnectionOrientedTransportMapping<A extends Address> extends TransportMapping<A> {

    /**
     * Resume sending of messages to the specified address.
     * @param addressToResumeSending
     *    an arbitrary remote address for which any messages send by
     *    {@link #sendMessage(Address, byte[], TransportStateReference, long, int)} should be dropped before sending
     *    and reopening a connection to that address.
     * @return
     *    {@code true} if the specified address was previously suspended and is now resumed to allow sending messages,
     *    {@code false} otherwise.
     * @since 3.4.4
     */
    boolean resumeAddress(A addressToResumeSending);

    /**
     * Suspend sending of messages to the specified address, regardless if a connection is already established or
     * not. To be able to send messages again to the specified address using
     * {@link #sendMessage(Address, byte[], TransportStateReference, long, int)}, call {@link #resumeAddress}.
     * @param addressToSuspendSending
     *    an arbitrary remote address for which any messages send by
     *    {@link #sendMessage(Address, byte[], TransportStateReference, long, int)} should be dropped before sending
     *    and reopening a connection to that address.
     * @since 3.4.4
     */
    void suspendAddress(A addressToSuspendSending);

    /**
     * Checks whether a server for incoming requests is enabled.
     *
     * @return boolean
     */
    boolean isServerEnabled();

    /**
     * Returns the {@code MessageLengthDecoder} used by this transport
     * mapping.
     *
     * @return a MessageLengthDecoder instance.
     */
    MessageLengthDecoder getMessageLengthDecoder();

    /**
     * Sets whether a server for incoming requests should be created when
     * the transport is set into listen state. Setting this value has no effect
     * until the {@link #listen()} method is called (if the transport is already
     * listening, {@link #close()} has to be called before).
     *
     * @param serverEnabled
     *         if {@code true} if the transport will listens for incoming
     *         requests after {@link #listen()} has been called.
     */
    void setServerEnabled(boolean serverEnabled);

    /**
     * Sets the {@code MessageLengthDecoder} that decodes the total
     * message length from the header of a message.
     *
     * @param messageLengthDecoder
     *         a MessageLengthDecoder instance.
     */
    void setMessageLengthDecoder(MessageLengthDecoder messageLengthDecoder);

    /**
     * Sets the connection timeout. This timeout specifies the time a connection
     * may be idle before it is closed.
     *
     * @param connectionTimeout
     *         the idle timeout in milliseconds. A zero or negative value will disable
     *         any timeout and connections opened by this transport mapping will stay
     *         opened until they are explicitly closed.
     */
    void setConnectionTimeout(long connectionTimeout);

    /**
     * Adds a transport state listener that is to be informed about connection
     * state changes.
     *
     * @param l
     *         a TransportStateListener.
     */
    void addTransportStateListener(TransportStateListener l);

    /**
     * Removes the supplied transport state listener.
     *
     * @param l
     *         a TransportStateListener.
     */
    void removeTransportStateListener(TransportStateListener l);

    /**
     * Closes the connection to the given remote address (socket).
     *
     * @param remoteAddress
     *         the address of the remote socket.
     *
     * @return {@code true} if the connection could be closed and
     * {@code false} if the connection does not exists.
     * @throws IOException
     *         if closing the connection with the specified remote address
     *         fails.
     * @since 1.7.1
     */
    boolean close(A remoteAddress) throws IOException;

    /**
     * Gets the {@link CommonTimer} that controls socket cleanup operations.
     * @return a socket cleaner timer.
     * @since 3.0
     */
    CommonTimer getSocketCleaner();

    /**
     * Gets the connection timeout in milliseconds
     * @return the timeout millis after which an inactive connection can be closed.
     * @since 3.0
     */
    long getConnectionTimeout();


}
