// Copyright © 2011 J.M. Linden
// This program is free software; you can redistribute it and/or
// modify it under the terms of the GNU General Public License
// as published by the Free Software Foundation; either version 2
// of the License, or (at your option) any later version.
//
// This program is distributed in the hope that it will be useful,
// but WITHOUT ANY WARRANTY; without even the implied warranty of
// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
// GNU General Public License for more details.
//
// You should have received a copy of the GNU General Public License
// along with this program; if not, write to the Free Software
// Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA  02110-1301, USA.

package org.mike.gielinor.game.service.event;

import static org.mike.gielinor.game.GameConstants.CYCLE_TIME;
import static org.mike.gielinor.game.model.World.getWorld;

import java.util.ArrayList;
import java.util.Iterator;
import java.util.List;

import org.mike.core.service.event.Event;
import org.mike.core.service.task.ConsecutiveTask;
import org.mike.core.service.task.ParallelTask;
import org.mike.core.service.task.Task;
import org.mike.gielinor.game.model.Entity;
import org.mike.gielinor.game.model.NPC;
import org.mike.gielinor.game.model.Player;
import org.mike.gielinor.game.model.update.UpdateAttributes;
import org.mike.gielinor.game.service.GameEngine;

/**
 * A {@link Task} which globally updates all registered {@link Entity entities}
 * each server cycle.
 *
 * @author J.M. Linden
 *
 */
public final class EntityUpdateEvent extends Event {

    /**
     * The {@link List} of all tick {@link Task}s.
     */
    private final List<Task> tickTasks = new ArrayList<Task>();

    /**
     * The {@link List} of all update {@link Task}s.
     */
    private final List<Task> updateTasks = new ArrayList<Task>();

    /**
     * The {@link List} of all reset {@link Task}s.
     */
    private final List<Task> resetTasks = new ArrayList<Task>();

    /**
     * The {@link GameEngine} to {@link #execute() execute} the cycle
     * {@link Task}s in.
     */
    private final GameEngine engine = getWorld().getEngine();

    /**
     * Creates a new {@link EntityUpdateEvent} with the default delay of the
     * server's cycle time..
     */
    public EntityUpdateEvent() {
        super(CYCLE_TIME);
    }

    @Override
    public void execute() {
        tickTasks.clear();
        updateTasks.clear();
        resetTasks.clear();

        for (NPC npc : getWorld().getNPCs()) {
            // fetch the cached updating tasks
            final UpdateAttributes ua = npc.getUpdateAttributes();
            tickTasks.add(ua.getTickTask());
            resetTasks.add(ua.getResetTask());
        }

        final Iterator<Player> it$ = getWorld().getPlayers().iterator();
        while (it$.hasNext()) {
            final Player player = it$.next();
            if (!player.getChannel().isConnected()) {
                it$.remove();
            } else {
                // fetch the cached updating tasks
                final UpdateAttributes ua = player.getUpdateAttributes();
                tickTasks.add(ua.getTickTask());
                updateTasks.add(new ConsecutiveTask(ua.getUpdateTasks()));
                resetTasks.add(ua.getResetTask());
            }
        }

        // tick tasks can no longer be parallel due to region code
        final Task tickTask = new ConsecutiveTask(
                tickTasks.toArray(new Task[0]));
        final Task updateTask = new ParallelTask(engine,
                updateTasks.toArray(new Task[0]));
        final Task resetTask = new ParallelTask(engine,
                resetTasks.toArray(new Task[0]));

        getWorld().submit(new ConsecutiveTask(tickTask, updateTask, resetTask));
    }

}