/*
 * Copyright 2006-2019 DLR, Germany
 * 
 * SPDX-License-Identifier: EPL-1.0
 * 
 * https://rcenvironment.de/
 */

package de.rcenvironment.core.communication.testutils;

import de.rcenvironment.core.communication.channel.MessageChannelLifecycleListener;
import de.rcenvironment.core.communication.channel.MessageChannelTrafficListener;
import de.rcenvironment.core.communication.model.NetworkContactPoint;
import de.rcenvironment.core.communication.transport.spi.NetworkTransportProvider;

/**
 * Interface for operations on virtual instances/nodes that can be used as batch operations as well, in the sense that a single method call
 * can affect any number of nodes.
 * 
 * @see VirtualInstance
 * @see VirtualInstanceGroup
 * 
 * @author Robert Mischke
 */
public interface CommonVirtualInstanceControl {

    /**
     * Sets the given target state for all nodes. Setting a target state causes the receiving instance to modify its state so that it will
     * eventually (and usually, asynchronously) reach the given state, unless this is prevented by an internal error.
     * 
     * In the current {@link VirtualInstance} and {@link VirtualInstanceGroup} implementations, calling this method with "STARTED" may cause
     * receivers to enter the "STARTING" state, and calling it with "STOPPED" may cause them to enter the "STOPPING" state.
     * 
     * @param state the target that should be reached
     * @throws InterruptedException on interruption while waiting for a required lock/monitor
     * 
     */
    void setTargetState(VirtualInstanceState state) throws InterruptedException;

    /**
     * Waits until all nodes have reached a "stable" state, in the sense that they will not change their state without further method calls.
     * 
     * In the current {@link VirtualInstance} and {@link VirtualInstanceGroup} implementations, the INITIAL, STARTED and STOPPED states are
     * considered stable; STARTING and STOPPING are considered unstable.
     * 
     * @throws InterruptedException on interruption while waiting for the target state
     */
    void waitForStateChangesToFinish() throws InterruptedException;

    /**
     * Convenience method; equivalent to "setTargetState(STARTED); waitForStateChangesToFinish()".
     * 
     * @throws InterruptedException on interruption while waiting for the target state
     */
    void start() throws InterruptedException;

    /**
     * Convenience method; equivalent to "setTargetState(SIMULATED_CRASHING); waitForStateChangesToFinish()".
     * 
     * @throws InterruptedException on interruption while waiting for the target state
     */
    void simulateCrash() throws InterruptedException;

    /**
     * Convenience method; equivalent to "getService(MessageChannelService.class).overrideProtocolVersion(...)".
     * 
     * @param version the new protocol version string to use
     */
    void simulateCustomProtocolVersion(String version);

    /**
     * Convenience method; equivalent to "setTargetState(STOPPED); waitForStateChangesToFinish()".
     * 
     * @throws InterruptedException on interruption while waiting for the target state
     */
    void shutDown() throws InterruptedException;

    /**
     * Registers the given network transport for all nodes.
     * 
     * @param provider the new network transport provider
     */
    void registerNetworkTransportProvider(NetworkTransportProvider provider);

    /**
     * Registers a {@link MessageChannelLifecycleListener}.
     * 
     * @param listener the new listener
     */
    void addNetworkConnectionListener(MessageChannelLifecycleListener listener);

    /**
     * Registers a {@link MessageChannelTrafficListener}.
     * 
     * @param listener the new listener
     */
    void addNetworkTrafficListener(MessageChannelTrafficListener listener);

    /**
     * Registers the given network contact point as an initial peer for all nodes. Initial peers are contacted on startup, and possibly
     * later during refresh operations.
     * 
     * @param contactPoint the contact point to register
     */
    void addInitialNetworkPeer(NetworkContactPoint contactPoint);

}
