#region Copyright & License Information
/*
 * Copyright 2007-2010 The OpenRA Developers (see AUTHORS)
 * This file is part of OpenRA, which is free software. It is made 
 * available to you under the terms of the GNU General Public License
 * as published by the Free Software Foundation. For more information,
 * see LICENSE.
 */
#endregion

using System;
using System.Collections.Generic;
using OpenRA.GameRules;
using OpenRA.Traits;

namespace OpenRA.Mods.RA
{
	public class Barrel
	{
		public int2 Position;				// position in turret space
		public int Facing;					// deviation from turret facing
	}

	public class Turret
	{
		public float Recoil = 0.0f;			// remaining recoil fraction
		public int2 UnitSpacePosition;		// where, in the unit's local space.
		public int2 ScreenSpacePosition;	// screen-space hack to make things line up good.

		public Turret(int[] offset)
		{
			ScreenSpacePosition = offset.AbsOffset().ToInt2();
			UnitSpacePosition = offset.RelOffset().ToInt2();
		}
	}

	public class Weapon
	{
		public WeaponInfo Info;
		public int FireDelay = 0;			// time (in frames) until the weapon can fire again
		public int Burst = 0;				// burst counter

		public Barrel[] Barrels;			// where projectiles are spawned, in local turret space.
		public Turret Turret;				// where this weapon is mounted -- possibly shared

		public Weapon(string weaponName, Turret turret, int[] localOffset)
		{
			Info = Rules.Weapons[weaponName.ToLowerInvariant()];
			Burst = Info.Burst;
			Turret = turret;

			var barrels = new List<Barrel>();
			for (var i = 0; i < localOffset.Length / 3; i++)
				barrels.Add(new Barrel
				{
					Position = new int2(localOffset[3 * i], localOffset[3 * i + 1]),
					Facing = localOffset[3 * i + 2]
				});

			// if no barrels specified, the default is "turret position; turret facing".
			if (barrels.Count == 0)
				barrels.Add(new Barrel { Position = int2.Zero, Facing = 0 });

			Barrels = barrels.ToArray();
		}

		public bool IsReloading { get { return FireDelay > 0; } }

		public void Tick()
		{
			if (FireDelay > 0) --FireDelay;
			Turret.Recoil = Math.Max(0f, Turret.Recoil - .2f);
		}

		public bool IsValidAgainst(Target target)
		{
			return Combat.WeaponValidForTarget(Info, target);
		}

		public void FiredShot()
		{
			Turret.Recoil = 1;

			if (--Burst > 0)
				FireDelay = Info.BurstDelay;
			else
			{
				FireDelay = Info.ROF;
				Burst = Info.Burst;
			}
		}
	}
}