using System.Collections;
using System.Collections.Generic;
using UnityEngine;

namespace BNG {
    public class Explosive : MonoBehaviour {

        [Header("Explosion Settings : ")]
        [Tooltip("Objects within this radius will have damage and force applied to it")]
        public float ExplosionRadius = 5f;

        [Tooltip("Apply damage to an item if it has a Damageable component attached. ")]
        public float ExplosionDamage = 0f;

        [Tooltip("If an object has a Rigidbody and is within ExplosionRadius, it will have this amount of ExplosionForce added to it")]
        public float ExplosionForce = 500f;

        [Tooltip("Add an UpwardsModifier to AddExplosionForce. Use this to make objects fly more up into the air, instead of just outwardly.")]
        public float ExplosiveUpwardsModifier = 3f;
        

        [Header("Shown for Debug : ")]
        public bool ShowExplosionRadius = false;

        public virtual void DoExplosion() {
            StartCoroutine(explosionRoutine());
        }

        IEnumerator explosionRoutine() {

            // Get all objects in explosion radius
            Collider[] colliders = Physics.OverlapSphere(transform.position, ExplosionRadius);

            // First Damage all of the items
            for (int x = 0; x < colliders.Length; x++) {
                Collider hit = colliders[x];

                // Apply Damage
                if (ExplosionDamage > 0) {
                    Damageable damageable = hit.GetComponent<Damageable>();
                    if (damageable) {
                        
                        if(hit.GetComponent<Explosive>() != null) {
                            // Add slight delay do damaging explosives so everything doesn't go off at once
                            StartCoroutine(dealDelayedDamaged(damageable, 0.1f));
                        }
                        else {
                            damageable.DealDamage(ExplosionDamage, hit.ClosestPoint(transform.position), transform.eulerAngles, true, gameObject, hit.gameObject);
                        }
                    }
                }
            }

            
            // Wait a frame so physics can be applied after damaging the items
            yield return new WaitForFixedUpdate();
            colliders = Physics.OverlapSphere(transform.position, ExplosionRadius);

            // Then Add Physics Force
            for (int x = 0; x < colliders.Length; x++) {
                Collider hit = colliders[x];

                Rigidbody rb = hit.GetComponent<Rigidbody>();

                // Add physics force
                if (rb != null) {
                    rb.AddExplosionForce(ExplosionForce, transform.position, ExplosionRadius, ExplosiveUpwardsModifier);
                }
            }

            yield return null;
        }

        IEnumerator dealDelayedDamaged(Damageable damageable, float delayTime) {
            yield return new WaitForSeconds(delayTime);

            damageable.DealDamage(ExplosionDamage);
        }

        void OnDrawGizmosSelected() {
            // Draw a yellow sphere at the transform's position
            if(ShowExplosionRadius) {
                Gizmos.color = Color.yellow;
                Gizmos.DrawSphere(transform.position, ExplosionRadius);
            }
        }
    }
}