package org.litesoft.GWT.eventbus.client;

import java.util.*;

public class EventSubscriptionCollector
{
    /**
     * Add a handler to be triggered for the events of the given name.
     *
     * @param pEventName - nonNull
     * @param pListener  - nonNull
     */
    public final EventSubscriptionCollector subscribe( String pEventName, EventPackageListener pListener )
    {
        LLsubscribe( new EventSimpleSubscriptionStructure( pEventName, pListener ) );
        return this;
    }

    /**
     * Add a handler to be triggered for the events of the given name from pSubscriber.
     *
     * @param pSubscriber - null ignored
     */
    public final EventSubscriptionCollector subscribe( EventPackageSubscriber pSubscriber )
    {
        if ( pSubscriber != null )
        {
            LLsubscribe( new EventSubscriberStructure( pSubscriber ) );
        }
        return this;
    }

    /**
     * Add a handler to be triggered for the events of the given name from pStructure.
     *
     * @param pStructure - null ignored
     */
    public final EventSubscriptionCollector subscribe( EventSubscriptionStructure pStructure )
    {
        if ( pStructure != null )
        {
            LLsubscribe( pStructure );
        }
        return this;
    }

    /**
     * Add handlers to be triggered for the events of the given name from the pStructures.
     *
     * @param pStructures - null/ ignored
     */
    public final synchronized EventSubscriptionCollector subscribe(
            EventSubscriptionStructure[] pStructures )
    {
        if ( pStructures != null )
        {
            for ( int i = 0; i < pStructures.length; i++ )
            {
                subscribe( pStructures[i] );
            }
        }
        return this;
    }

    /**
     * @return !null, and no nulls in array
     */
    public final synchronized EventSubscriptionStructure[] getSubscriptions()
    {
        if ( mSubscriptions.isEmpty() )
        {
            return EventSubscriptionStructure.EMPTY_ARRAY;
        }
        EventSubscriptionStructure[] rv = new EventSubscriptionStructure[mSubscriptions.size()];
        for ( int i = 0; i < mSubscriptions.size(); i++ )
        {
            rv[i] = mSubscriptions.get( i );
        }
        return rv;
    }

    private List<EventSubscriptionStructure> mSubscriptions = new ArrayList<EventSubscriptionStructure>();

    private synchronized void LLsubscribe( EventSubscriptionStructure pSubscription )
    {
        mSubscriptions.add( pSubscription );
    }
}