/*
 * Copyright 2015 Christian Basler
 *
 * 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 ch.dissem.bitmessage.ports;

import ch.dissem.bitmessage.entity.CustomMessage;
import ch.dissem.bitmessage.entity.ObjectMessage;
import ch.dissem.bitmessage.entity.valueobject.InventoryVector;
import ch.dissem.bitmessage.utils.Property;

import java.io.IOException;
import java.net.InetAddress;
import java.util.Collection;
import java.util.concurrent.Future;

/**
 * Handles incoming messages
 */
public interface NetworkHandler {
    int NETWORK_MAGIC_NUMBER = 8;
    int HEADER_SIZE = 24;
    int MAX_PAYLOAD_SIZE = 1600003;
    int MAX_MESSAGE_SIZE = HEADER_SIZE + MAX_PAYLOAD_SIZE;

    /**
     * Connects to the trusted host, fetches and offers new messages and disconnects afterwards.
     * <p>
     * An implementation should disconnect if either the timeout is reached or the returned thread is interrupted.
     * </p>
     */
    Future<?> synchronize(InetAddress server, int port, long timeoutInSeconds);

    /**
     * Send a custom message to a specific node (that should implement handling for this message type) and returns
     * the response, which in turn is expected to be a {@link CustomMessage}.
     *
     * @param server  the node's address
     * @param port    the node's port
     * @param request the request
     * @return the response
     */
    CustomMessage send(InetAddress server, int port, CustomMessage request);

    /**
     * Start a full network node, accepting incoming connections and relaying objects.
     */
    void start();

    /**
     * Stop the full network node.
     */
    void stop();

    /**
     * Offer new objects to up to 8 random nodes.
     */
    void offer(InventoryVector iv);

    /**
     * Request each of those objects from a node that knows of the requested object.
     *
     * @param inventoryVectors of the objects to be requested
     */
    void request(Collection<InventoryVector> inventoryVectors);

    Property getNetworkStatus();

    boolean isRunning();

    interface MessageListener {
        void receive(ObjectMessage object) throws IOException;
    }
}