#region Copyright & License Information
/*
 * Copyright 2007,2009,2010 Chris Forbes, Robert Pepperell, Matthew Bowra-Dean, Paul Chote, Alli Witheford.
 * This file is part of OpenRA.
 * 
 *  OpenRA 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 3 of the License, or
 *  (at your option) any later version.
 * 
 *  OpenRA 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 OpenRA.  If not, see <http://www.gnu.org/licenses/>.
 */
#endregion

using System;

namespace OpenRA.Traits.Activities
{
	class FlyTimed : IActivity
	{
		public IActivity NextActivity { get; set; }
		int remainingTicks;
		int targetAltitude;

		public FlyTimed(int ticks, int targetAltitude) { remainingTicks = ticks; this.targetAltitude = targetAltitude; }

		public IActivity Tick(Actor self)
		{
			if (remainingTicks == 0)
				return NextActivity;

			--remainingTicks;

			var unit = self.traits.Get<Unit>();
			var speed = .2f * Util.GetEffectiveSpeed(self);
			var angle = unit.Facing / 128f * Math.PI;

			self.CenterLocation += speed * -float2.FromAngle((float)angle);
			self.Location = ((1 / 24f) * self.CenterLocation).ToInt2();

			unit.Altitude += Math.Sign(targetAltitude - unit.Altitude);
			return this;
		}

		public void Cancel(Actor self) { remainingTicks = 0; NextActivity = null; }
	}
}