/// ---------------------------------------------
/// Ultimate Character Controller
/// Copyright (c) Opsive. All Rights Reserved.
/// https://www.opsive.com
/// ---------------------------------------------

namespace Opsive.UltimateCharacterController.Objects
{
    using Opsive.Shared.Game;
    using Opsive.UltimateCharacterController.SurfaceSystem;
    using UnityEngine;

    /// <summary>
    /// The Projectile component moves a Destructible object along the specified path. Can apply damage at the collision point.
    /// </summary>
    public class Projectile : Destructible
    {
        [Tooltip("The length of time the projectile should exist before it deactivates if no collision occurs.")]
        [SerializeField] protected float m_Lifespan = 10;

        private ScheduledEventBase m_ScheduledDeactivation;

        /// <summary>
        /// Initializes the object. This will be called from an object creating the projectile (such as a weapon).
        /// </summary>
        /// <param name="velocity">The velocity to apply.</param>
        /// <param name="torque">The torque to apply.</param>
        /// <param name="damageAmount">The amount of damage to apply to the hit object.</param>
        /// <param name="impactForce">The amount of force to apply to the hit object.</param>
        /// <param name="impactForceFrames">The number of frames to add the force to.</param>
        /// <param name="impactLayers">The layers that the projectile can impact with.</param>
        /// <param name="impactStateName">The name of the state to activate upon impact.</param>
        /// <param name="impactStateDisableTimer">The number of seconds until the impact state is disabled.</param>
        /// <param name="surfaceImpact">A reference to the Surface Impact triggered when the object hits an object.</param>
        /// <param name="originator">The object that instantiated the trajectory object.</param>
        public override void Initialize(Vector3 velocity, Vector3 torque, float damageAmount, float impactForce, int impactForceFrames, LayerMask impactLayers,
                                     string impactStateName, float impactStateDisableTimer, SurfaceImpact surfaceImpact, GameObject originator)
        {
            // The projectile can deactivate after it comes in contact with another object or after a specified amount of time. Do the scheduling here to allow
            // it to activate after a set amount of time.
            m_ScheduledDeactivation = Scheduler.Schedule(m_Lifespan, Deactivate);

            base.Initialize(velocity, torque, damageAmount, impactForce, impactForceFrames, impactLayers, impactStateName, impactStateDisableTimer, surfaceImpact, originator);
        }

        /// <summary>
        /// The projectile has reached its lifespan.
        /// </summary>
        private void Deactivate()
        {
            OnCollision(null);
        }

        /// <summary>
        /// The object has collided with another object.
        /// </summary>
        /// <param name="hit">The RaycastHit of the object. Can be null.</param>
        protected override void OnCollision(RaycastHit? hit)
        {
            if (m_ScheduledDeactivation != null) {
                Scheduler.Cancel(m_ScheduledDeactivation);
                m_ScheduledDeactivation = null;
            }
            base.OnCollision(hit);
        }

        /// <summary>
        /// The component has been disabled.
        /// </summary>
        protected override void OnDisable()
        {
            base.OnDisable();

            if (m_ScheduledDeactivation != null) {
                Scheduler.Cancel(m_ScheduledDeactivation);
                m_ScheduledDeactivation = null;
            }
        }
    }
}