/*
 * Copyright (c) Meta Platforms, Inc. and affiliates.
 * All rights reserved.
 *
 * Licensed under the Oculus SDK License Agreement (the "License");
 * you may not use the Oculus SDK except in compliance with the License,
 * which is provided at the time of installation or download, or which
 * otherwise accompanies this software in either electronic or hard copy form.
 *
 * You may obtain a copy of the License at
 *
 * https://developer.oculus.com/licenses/oculussdk/
 *
 * Unless required by applicable law or agreed to in writing, the Oculus SDK
 * distributed under the License is distributed on an "AS IS" BASIS,
 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 * See the License for the specific language governing permissions and
 * limitations under the License.
 */

using System;
using UnityEngine.Assertions;
using UnityEngine;
using Oculus.Interaction;

namespace Oculus.Interaction
{
    public class AudioPhysics : MonoBehaviour
    {
        [Tooltip("Add a reference to the rigidbody on this gameobject.")]
        [SerializeField]
        private Rigidbody _rigidbody;

        [Tooltip("Reference an audio trigger instance for soft and hard collisions.")]
        [SerializeField]
        private ImpactAudio _impactAudioEvents;
        [Tooltip("Collisions below this value will play a soft audio event, and collisions above will play a hard audio event.")]
        [Range(0.0f, 8.0f)]
        [SerializeField]
        private float _velocitySplit = 1.0f;

        [Tooltip("Collisions below this value will be ignored and will not play audio.")]
        [Range(0.0f, 2.0f)]
        [SerializeField]
        private float _minimumVelocity = 0;

        [Tooltip("The shortest amount of time in seconds between collisions. Used to cull multiple fast collision events.")]
        [Range(0.0f, 2.0f)]
        [SerializeField]
        private float _timeBetweenCollisions = 0.2f;

        [Tooltip("By default (false), when two physics objects collide with physics audio components, we only play the one with the higher velocity." +
            "Setting this to true will allow both impacts to play.")]
        [SerializeField]
        private bool _allowMultipleCollisions = false;
        private float _timeAtLastCollision = 0f;

        protected bool _started = false;

        private CollisionEvents _collisionEvents;

        protected virtual void Start()
        {
            this.BeginStart(ref _started);
            this.AssertField(_impactAudioEvents.SoftCollisionSound, nameof(_impactAudioEvents.SoftCollisionSound));
            this.AssertField(_impactAudioEvents.HardCollisionSound, nameof(_impactAudioEvents.HardCollisionSound));
            this.AssertField(_rigidbody, nameof(_rigidbody));
            _collisionEvents = _rigidbody.gameObject.AddComponent<CollisionEvents>();
            this.EndStart(ref _started);
        }

        protected virtual void OnEnable()
        {
            if (_started)
            {
                _collisionEvents.WhenCollisionEnter += HandleCollisionEnter;
            }
        }

        protected virtual void OnDisable()
        {
            if (_started)
            {
                _collisionEvents.WhenCollisionEnter -= HandleCollisionEnter;
            }
        }

        protected virtual void OnDestroy()
        {
            if (_collisionEvents != null)
            {
                Destroy(_collisionEvents);
            }
        }

        private void HandleCollisionEnter(Collision collision)
        {
            TryPlayCollisionAudio(collision, _rigidbody);
        }

        private void TryPlayCollisionAudio(Collision collision, Rigidbody rigidbody)
        {
            // capture the velocity of the impact. TODO lets see if there is another way to get this data that might be better
            float collisionMagnitude = collision.relativeVelocity.sqrMagnitude;

            // make sure the gameobject we collided with is valid
            if (collision.collider.gameObject == null)
            {
                return;
            }

            // cull all the collisions we want to ignore

            // ignore any physics impacts that happen too close together
            float deltaTime = Time.time - _timeAtLastCollision;
            if (_timeBetweenCollisions > deltaTime)
            {
                return;
            }

            // only play a single sound when two physics objects collide

            if (_allowMultipleCollisions == false)
            {
                // check the object we collided with if it has an audio physics component
                if (collision.collider.gameObject.TryGetComponent(out AudioPhysics otherAudioPhysicsObj))
                {
                    if (GetObjectVelocity(otherAudioPhysicsObj) > GetObjectVelocity(this))
                    {
                        return;
                    }
                }
            }

            // update time variable for impacts too close together
            _timeAtLastCollision = Time.time;

            // play the audio
            PlayCollisionAudio(_impactAudioEvents, collisionMagnitude);
        }

        private void PlayCollisionAudio(ImpactAudio impactAudio, float magnitude)
        {
            // early out if there is no physics audio available
            if (impactAudio.HardCollisionSound == null || impactAudio.SoftCollisionSound == null)
            {
                return;
            }

            // cull audio by minimum velocity value
            if (magnitude > _minimumVelocity)
            {
                // play the hard or soft sound determined by the slider
                if (magnitude > _velocitySplit && impactAudio.HardCollisionSound != null)
                {
                    PlaySoundOnAudioTrigger(impactAudio.HardCollisionSound);
                }
                else
                {
                    PlaySoundOnAudioTrigger(impactAudio.SoftCollisionSound);
                }
            }
        }

        private static float GetObjectVelocity(AudioPhysics target)
        {
#pragma warning disable CS0618 // Type or member is obsolete
            return target._rigidbody.velocity.sqrMagnitude;
#pragma warning restore CS0618 // Type or member is obsolete
        }

        private void PlaySoundOnAudioTrigger(AudioTrigger audioTrigger)
        {
            if (audioTrigger != null)
            {
                audioTrigger.PlayAudio();
            }
        }

        public class CollisionEvents : MonoBehaviour
        {
            public event Action<Collision> WhenCollisionEnter = delegate { };

            private void OnCollisionEnter(Collision collision)
            {
                WhenCollisionEnter.Invoke(collision);
            }
        }
    }

    [Serializable]
    public struct ImpactAudio
    {
        [Tooltip("Hard collision sound will play when impact velocity is above the velocity split value.")]
        [SerializeField]
        private AudioTrigger _hardCollisionSound;
        [Tooltip("Soft collision sound will play when impact velocity is below the velocity split value.")]
        [SerializeField]
        private AudioTrigger _softCollisionSound;
        public AudioTrigger HardCollisionSound => _hardCollisionSound;
        public AudioTrigger SoftCollisionSound => _softCollisionSound;
    }
}