using UnityEngine;


namespace AmazingAssets.CurvedWorld.Example
{
    public class ShellExplosion : MonoBehaviour
    {
        public LayerMask m_TankMask;                        // Used to filter what the explosion affects, this should be set to "Players".
        public ParticleSystem m_ExplosionParticles;         // Reference to the particles that will play on explosion.
        public AudioSource m_ExplosionAudio;                // Reference to the audio that will play on explosion.
        public float m_MaxDamage = 100f;                    // The amount of damage done if the explosion is centred on a tank.
        public float m_ExplosionForce = 1000f;              // The amount of force added to a tank at the centre of the explosion.
        public float m_MaxLifeTime = 2f;                    // The time in seconds before the shell is removed.
        public float m_ExplosionRadius = 5f;                // The maximum distance away from the explosion tanks can be and are still affected.


        private void Start ()
        {
            // If it isn't destroyed by then, destroy the shell after it's lifetime.
            Destroy (gameObject, m_MaxLifeTime);
        }


        private void OnTriggerEnter (Collider other)
        {
			// Collect all the colliders in a sphere from the shell's current position to a radius of the explosion radius.
            Collider[] colliders = Physics.OverlapSphere (transform.position, m_ExplosionRadius, m_TankMask);

            // Go through all the colliders...
            for (int i = 0; i < colliders.Length; i++)
            {
                // ... and find their rigidbody.
                Rigidbody targetRigidbody = colliders[i].GetComponent<Rigidbody> ();

                // If they don't have a rigidbody, go on to the next collider.
                if (!targetRigidbody)
                    continue;

                // Add an explosion force.
                targetRigidbody.AddExplosionForce (m_ExplosionForce, transform.position, m_ExplosionRadius);

            }

            // Unparent the particles from the shell.
            m_ExplosionParticles.transform.parent = null;

            // Play the particle system.
            m_ExplosionParticles.Play();

            // Play the explosion sound effect.
            m_ExplosionAudio.Play();

            // Once the particles have finished, destroy the gameobject they are on.
            ParticleSystem.MainModule mainModule = m_ExplosionParticles.main;
            Destroy (m_ExplosionParticles.gameObject, mainModule.duration);

            // Destroy the shell.
            Destroy (gameObject);
        }
    }
}