// Original code dervied from:
// https://github.com/thelinuxlich/starwarrior_CSharp/blob/master/StarWarrior/StarWarrior/Systems/CollisionSystem.cs

// --------------------------------------------------------------------------------------------------------------------
// <copyright file="CollisionSystem.cs" company="GAMADU.COM">
//     Copyright © 2013 GAMADU.COM. All rights reserved.
//
//     Redistribution and use in source and binary forms, with or without modification, are
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//           conditions and the following disclaimer.
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//        2. Redistributions in binary form must reproduce the above copyright notice, this list
//           of conditions and the following disclaimer in the documentation and/or other materials
//           provided with the distribution.
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//     THIS SOFTWARE IS PROVIDED BY GAMADU.COM 'AS IS' AND ANY EXPRESS OR IMPLIED
//     WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND
//     FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL GAMADU.COM OR
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//     The views and conclusions contained in the software and documentation are those of the
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// </copyright>
// <summary>
//   The collision system.
// </summary>
// --------------------------------------------------------------------------------------------------------------------

using Microsoft.Xna.Framework;
using MonoGame.Extended;
using MonoGame.Extended.Entities.Systems;

namespace StarWarrior.Systems
{
    public class CollisionSystem : UpdateSystem
    {
        public override void Update(GameTime gameTime)
        {
            //var bullets = EntityManager.GetEntitiesByGroup("BULLETS");
            //var ships = EntityManager.GetEntitiesByGroup("SHIPS");
            //if (bullets == null || ships == null)
            //    return;

            //// ReSharper disable once ForCanBeConvertedToForeach
            //for (var shipIndex = 0; ships.Count > shipIndex; ++shipIndex)
            //{
            //    var ship = ships[shipIndex];

            //    // ReSharper disable once ForCanBeConvertedToForeach
            //    for (var bulletIndex = 0; bullets.Count > bulletIndex; ++bulletIndex)
            //    {
            //        var bullet = bullets[bulletIndex];
            //        var bulletTransform = bullet.Get<Transform2>();
            //        var shipTransform = ship.Get<Transform2>();

            //        if (!CollisionExists(bulletTransform, shipTransform))
            //            continue;

            //        var bulletExplosion = EntityManager.CreateEntityFromTemplate(BulletExplosionTemplate.Name);
            //        bulletExplosion.Get<Transform2>().Position = bulletTransform.Position;
            //        bullet.Destroy();

            //        var healthComponent = ship.Get<HealthComponent>();
            //        healthComponent.AddDamage(4);

            //        if (healthComponent.IsAlive)
            //            continue;

            //        var shipExplosion = EntityManager.CreateEntityFromTemplate(ShipExplosionTemplate.Name);
            //        shipExplosion.Get<Transform2>().Position = shipTransform.Position;
            //        ship.Destroy();
            //        break;
            //    }
            //}


        }

        // ReSharper disable once SuggestBaseTypeForParameter
        private static bool CollisionExists(Transform2 bulletTransform, Transform2 shipTransform)
        {
            return Vector2.Distance(bulletTransform.WorldPosition, shipTransform.WorldPosition) < 20;
        }
    }
}