/**
 * Copyright 2007-2016, Kaazing Corporation. All rights reserved.
 *
 * 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.apache.mina.core.session;

import org.apache.mina.core.write.WriteRequest;

/**
 * An I/O event or an I/O request that MINA provides.
 * Most users won't need to use this class.  It is usually used by internal
 * components to store I/O events.
 *
 * @author <a href="http://mina.apache.org">Apache MINA Project</a>
 */
public class IoEvent implements Runnable {
    private final IoEventType type;

    private final IoSession session;

    private final Object parameter;

    public IoEvent(IoEventType type, IoSession session, Object parameter) {
        if (type == null) {
            throw new NullPointerException("type");
        }
        if (session == null) {
            throw new NullPointerException("session");
        }
        this.type = type;
        this.session = session;
        this.parameter = parameter;
    }

    public IoEventType getType() {
        return type;
    }

    public IoSession getSession() {
        return session;
    }

    public Object getParameter() {
        return parameter;
    }
    
    public void run() {
        fire();
    }

    public void fire() {
        switch (getType()) {
        case MESSAGE_RECEIVED:
            getSession().getFilterChain().fireMessageReceived(getParameter());
            break;
        case MESSAGE_SENT:
            getSession().getFilterChain().fireMessageSent((WriteRequest) getParameter());
            break;
        case WRITE:
            getSession().getFilterChain().fireFilterWrite((WriteRequest) getParameter());
            break;
        case CLOSE:
            getSession().getFilterChain().fireFilterClose();
            break;
        case EXCEPTION_CAUGHT:
            getSession().getFilterChain().fireExceptionCaught((Throwable) getParameter());
            break;
        case SESSION_IDLE:
            getSession().getFilterChain().fireSessionIdle((IdleStatus) getParameter());
            break;
        case SESSION_OPENED:
            getSession().getFilterChain().fireSessionOpened();
            break;
        case SESSION_CREATED:
            getSession().getFilterChain().fireSessionCreated();
            break;
        case SESSION_CLOSED:
            getSession().getFilterChain().fireSessionClosed();
            break;
        default:
            throw new IllegalArgumentException("Unknown event type: " + getType());
        }
    }

    @Override
    public String toString() {
        if (getParameter() == null) {
            return "[" + getSession() + "] " + getType().name();
        }
        
        return "[" + getSession() + "] " + getType().name() + ": "
                    + getParameter();
    }
}
