using System;
using System.Collections;
using System.Collections.Generic;
using UnityEngine;
using Random = UnityEngine.Random;

namespace RayFire
{
    [AddComponentMenu ("RayFire/Rayfire Bomb")]
    [HelpURL ("https://rayfirestudios.com/unity-online-help/components/unity-bomb-component/")]
    public class RayfireBomb : MonoBehaviour
    {
        public enum RangeType
        {
            Spherical = 0
        }

        // Strength fade Type
        public enum FadeType
        {
            Linear      = 0,
            Exponential = 1,
            ByCurve     = 3,
            None        = 2
        }

        // Projectiles class
        [Serializable]
        public class Projectile
        {
            public Vector3          positionPivot;
            public Vector3          positionClosest;
            public float            fade;
            public Rigidbody        rb;
            public RayfireRigid     rigid;
            public Quaternion       rotation;
            public RFShard          shard;
            public RayfireRigidRoot rigidRoot;
        }
        
        // UI
        public bool      showGizmo;
        public RangeType rangeType;
        public FadeType  fadeType;
        public float     range = 5f;
        public int       deletion;
        public float     strength    = 1f;
        public int       variation   = 50;
        public int       chaos       = 30;
        public bool      forceByMass = true;
        public bool      affectInactive;
        public bool      affectKinematic;
        public float     heightOffset;
        public float     delay;
        public bool      atStart;
        public bool      destroy;
        public bool      applyDamage;
        public float     damageValue;
        public bool      play;
        public float     volume = 1f;
        public AudioClip clip;
        public int       mask      = -1;
        public string    tagFilter = "Untagged";
        public AnimationCurve curve = new AnimationCurve (
            new Keyframe (0,    1, -1, 0), new Keyframe (0.5f, 1, 0, 0),
            new Keyframe (0.7f, 0, -1, 0), new Keyframe (1,    0, 0,  -1));
        
        // Event
        public RFExplosionEvent explosionEvent = new RFExplosionEvent();
        
        // Non Serialized
        [NonSerialized] Vector3          bombPosition;
        [NonSerialized] Vector3          explPosition;
        [NonSerialized] Collider[]       colliders;
        [NonSerialized] List<Rigidbody>  rigidbodies         = new List<Rigidbody>();
        [NonSerialized] List<Projectile> projectiles         = new List<Projectile>();
        [NonSerialized] List<Projectile> deletionProjectiles = new List<Projectile>();
        
        /// /////////////////////////////////////////////////////////
        /// Common
        /// /////////////////////////////////////////////////////////

        // Awake
        void Awake()
        {
            // Clear
            ClearLists();
        }
        
        // Auto explode
        void Start()
        {
            if (Application.isPlaying == true)
                if (atStart == true)
                    Explode (delay);
        }
        
        // Copy properties from another Rigs
        public void CopyFrom (RayfireBomb scr)
        {
            rangeType       = scr.rangeType;
            fadeType        = scr.fadeType;
            range           = scr.range;
            deletion        = scr.deletion;
            strength        = scr.strength;
            variation       = scr.variation;
            chaos           = scr.chaos;
            forceByMass     = scr.forceByMass;
            affectKinematic = scr.affectKinematic;
            heightOffset    = scr.heightOffset;
            delay           = scr.delay;
            applyDamage     = scr.applyDamage;
            damageValue     = scr.damageValue;
            clip            = scr.clip;
            volume          = scr.volume;
        }

        /// /////////////////////////////////////////////////////////
        /// Explode
        /// /////////////////////////////////////////////////////////

        // Explode bomb
        public void Explode (float delayLoc)
        {
            if (delayLoc == 0)
                Explode();
            else if (delayLoc > 0)
                StartCoroutine (ExplodeCor());
        }

        // Init delay before explode
        IEnumerator ExplodeCor()
        {
            // Wait delay time
            yield return new WaitForSeconds (delay);

            // Explode
            Explode();
        }

        // Explode bomb
        void Explode()
        {
            // Set bomb and explosion positions
            SetPositions();

            // Setup collider, projectiles and rigidbodies
            if (Setup() == false)
                return;
            
            // Recollect projectiles if damage with demolition.
            if (SetRigidDamage() == true)
                if (Setup() == false)
                    return;
            
            // Deletion
            Deletion();

            // Activate inactive and kinematic objects
            Activate();
            
            // Apply explosion force
            SetForce();
            
            // Event
            RFExplosionEvent.ExplosionEvent (this);

            // Explosion Sound
            PlayAudio();

            // Clear lists in runtime
            if (Application.isEditor == false)
                ClearLists();

            // Destroy
            if (destroy == true)
                Destroy (gameObject, 1f);
        }

        // Explosion Sound
        void PlayAudio()
        {
            if (play == true && clip != null)
            {
                // Fix volume
                if (volume < 0)
                    volume = 1f;

                // TODO Set volume bu range

                // Play clip
                AudioSource.PlayClipAtPoint (clip, transform.position, volume);
            }
        }

        // Setup collider, projectiles and rigidbodies
        bool Setup()
        {
            // Clear all lists
            ClearLists();

            // Set colliders by range type
            SetColliders();

            // Set rigidbodies by colliders
            SetProjectiles();
            
            // Nothing to explode
            if (projectiles.Count == 0)
                return false;

            return true;
        }

        // Reset all lists
        void ClearLists()
        {
            colliders = null;
            rigidbodies.Clear();
            projectiles.Clear();
        }
        
        /// /////////////////////////////////////////////////////////
        /// Restore
        /// /////////////////////////////////////////////////////////
        
        // Restore exploded objects transformation
        public void Restore()
        {
            RestoreProjectiles (projectiles);
            RestoreProjectiles (deletionProjectiles);
        }

        // Restore projectiles
        static void RestoreProjectiles (List<Projectile> prj)
        {
            for (int i = 0; i < prj.Count; i++)
                if (prj[i].rigid != null)
                    prj[i].rigid.ResetRigid();
                else if (prj[i].rb != null)
                {
                    prj[i].rb.velocity           = Vector3.zero;
                    prj[i].rb.angularVelocity    = Vector3.zero;
                    prj[i].rb.transform.SetPositionAndRotation (prj[i].positionPivot, prj[i].rotation);
                }
        }
            
        /// /////////////////////////////////////////////////////////
        /// Setups
        /// /////////////////////////////////////////////////////////

        // Set bomb and explosion positions
        void SetPositions()
        {
            // Set initial bomb and explosion positions
            bombPosition = transform.position;
            explPosition = transform.position;
            
            // Consider height offset
            if (heightOffset != 0)
                explPosition = bombPosition + transform.TransformDirection (0f, heightOffset, 0f);
        }

        // Set colliders by range type
        void SetColliders()
        {
            if (rangeType == RangeType.Spherical)
                colliders = Physics.OverlapSphere (explPosition, range, mask);
            //else if (rangeType == RangeType.Cylindrical)
            //    colliders = Physics.OverlapSphere(bombPosition, range * 2, mask);
        }

        // Set projectiles by colliders
        void SetProjectiles()
        {
            projectiles.Clear();
            
            // Collect all rigid bodies in range
            foreach (Collider col in colliders)
            {
                // Tag filter
                if (tagFilter != "Untagged" && col.gameObject.CompareTag (tagFilter) == false)
                    continue;
                
                // Get attached rigid body
                Rigidbody rb = col.attachedRigidbody;

                // No rb
                if (rb == null)
                    continue;

                // Create projectile if rigid body new. Could be several colliders on one object. TODO change to hash
                if (rigidbodies.Contains (rb) == false)
                {
                    Projectile projectile = new Projectile();
                    projectile.rb = rb;

                    // Transform
                    projectile.positionPivot = rb.transform.position;
                    projectile.rotation      = rb.transform.rotation;

                    // Get position of closest point to explosion position
                    projectile.positionClosest = col.bounds.ClosestPoint (explPosition);
  
                    // Get fade multiplier by range and distance
                    projectile.fade = Fade (explPosition, projectile.positionClosest);
                    
                    // Skip fragments out of range
                    if (projectile.fade <= 0)
                        continue;
                    
                    // Check for Rigid script
                    projectile.rigid = projectile.rb.GetComponent<RayfireRigid>();

                    // TODO optional targets, for quick search
                    
                    // Set RigidRoot amd Shard
                    if (projectile.rigid == null)
                    {
                        projectile.rigidRoot = projectile.rb.GetComponentInParent<RayfireRigidRoot>();
                        if (projectile.rigidRoot != null)
                        {
                            if (projectile.rigidRoot.collidersHash == null)
                            {
                                List<Collider> collidersTemp = new List<Collider>(projectile.rigidRoot.inactiveShards.Count);
                                for (int s = 0; s < projectile.rigidRoot.inactiveShards.Count; s++)
                                    collidersTemp.Add (projectile.rigidRoot.inactiveShards[s].col);
                                projectile.rigidRoot.collidersHash = new HashSet<Collider>(collidersTemp);
                            }
                            
                            // Collider belongs to inactive shard
                            if (projectile.rigidRoot.collidersHash.Contains (col) == true)
                            {
                                for (int i = 0; i < projectile.rigidRoot.inactiveShards.Count; i++)
                                {
                                    if (projectile.rigidRoot.inactiveShards[i].col == col)
                                    {
                                        projectile.shard = projectile.rigidRoot.inactiveShards[i];
                                        break;
                                    }
                                }
                            }
                        }
                    }

                    // Skip inactive fragments if affectInactive disabled
                    if (affectInactive == false)
                    {
                        if (projectile.rigid != null)
                            if (projectile.rigid.simulationType == SimType.Inactive)
                                continue;
                        
                        if (projectile.shard != null)
                            if (projectile.shard.sm == SimType.Inactive)
                                continue;
                    }

                    // Collect projectile
                    projectiles.Add (projectile);

                    // Remember rigid body
                    rigidbodies.Add (rb);
                }
            }

            
            // TODo nullify collider has list in RigidRoots
            
            // do not collect kinematic
            // collect rigid kinematic if can be activated
        }

        // Set RayFire Rigid refs for projectiles
        bool SetRigidDamage()
        {
            // Recollect state for new fragments after demolition
            bool recollectState = false;

            // Apply damage to rigid and demolish first
            if (applyDamage == true && damageValue > 0)
            {
                for (int i = 0; i < projectiles.Count; i++)
                {
                    // Rigid exist and damage enabled
                    if (projectiles[i].rigid != null && projectiles[i].rigid.damage.en == true)
                    {
                        // Apply damage and demolish
                        if (projectiles[i].rigid.ApplyDamage (damageValue * projectiles[i].fade, explPosition, range) == true)
                            recollectState = true;
                    }
                }
            }

            return recollectState;
        }

        // Deletion
        void Deletion()
        {
            if (deletion > 0)
            {
                // Get deletion projectiles and remove from force projectiles list
                deletionProjectiles = new List<Projectile>();
                for (int i = projectiles.Count - 1; i >= 0; i--)
                    if (Vector3.Distance (projectiles[i].positionClosest, explPosition) < range * deletion / 100f)
                    {
                        deletionProjectiles.Add (projectiles[i]);
                        projectiles.RemoveAt (i);
                    }
                
                // Destroy
                if (deletionProjectiles.Count > 0)
                    for (int i = 0; i < deletionProjectiles.Count; i++)
                    {
                        if (deletionProjectiles[i].rigid != null)
                            RayfireMan.DestroyFragment (deletionProjectiles[i].rigid, null);
                        else
                            Destroy (deletionProjectiles[i].rb.gameObject); 
                    }
            }
        }
        
        // Activate inactive and kinematic objects
        void Activate()
        {
            // Activate disabled
            if (affectInactive == false && affectKinematic == false)
                return;
            
            foreach (Projectile projectile in projectiles)
            {
                // Outside of range
                if (projectile.fade <= 0)
                    return;

                // Affect Kinematic rigid body
                if (affectKinematic == true && projectile.rb.isKinematic == true)
                {
                    // Convert kinematic to dynamic via rigid script
                    if (projectile.rigid != null)
                        projectile.rigid.Activate();

                    // Activate kinematic rigidRoot shard
                    else if (projectile.shard != null)
                    {
                        if (projectile.shard.sm == SimType.Kinematic)
                            RFActivation.ActivateShard (projectile.shard, projectile.rigidRoot);
                    }
                    
                    // Convert regular kinematic to dynamic
                    else
                    {
                        projectile.rb.isKinematic = false;

                        // TODO Set mass

                        // Set convex
                        MeshCollider meshCol = projectile.rb.gameObject.GetComponent<MeshCollider>();
                        if (meshCol != null && meshCol.convex == false)
                            meshCol.convex = true;
                    }
                    
                    // Skip inactive object activation. 
                    continue;
                }
                
                // Affect inactive
                if (affectInactive == true)
                {
                    // Activate inactive via rigid script
                    if (projectile.rigid != null)
                    {
                        if (projectile.rigid.simulationType == SimType.Inactive)
                            projectile.rigid.Activate();
                    }
                    
                    // Activate inactive rigidRoot shard
                    else if (projectile.shard != null)
                    {
                        if (projectile.shard.sm == SimType.Inactive)
                            RFActivation.ActivateShard (projectile.shard, projectile.rigidRoot);
                    }
                }
            }
        }
        
        // Apply explosion force, vector and rotation to projectiles
        void SetForce()
        {
            // Set same random state
            Random.InitState (1);

            // Set forceMode by mass state
            ForceMode forceMode = ForceMode.Impulse;
            if (forceByMass == false)
                forceMode = ForceMode.VelocityChange;
            
            // Get str for each object by explode type with variation
            foreach (Projectile projectile in projectiles)
            {
                // TODO check if not activated and doesn't need to be forced

                // Get local velocity strength
                float strVar  = strength * variation / 100f + strength;
                float str     = Random.Range (strength, strVar);
                float strMult = projectile.fade * str * 10f;

                // Get explosion vector from explosion position to projectile center of mass
                Vector3 vector = Vector (projectile);
                
                // Apply force
                projectile.rb.AddForce (vector * strMult, forceMode);

                // Get local rotation strength 
                Vector3 rot = new Vector3 (Random.Range (-chaos, chaos), Random.Range (-chaos, chaos), Random.Range (-chaos, chaos));

                // Set rotation impulse
                projectile.rb.angularVelocity = rot;
            }
        }
        
        /// /////////////////////////////////////////////////////////
        /// Support
        /// /////////////////////////////////////////////////////////

        // Fade multiplier
        float Fade (Vector3 bombPos, Vector3 fragPos)
        {
            // Get rate by fade type
            float fade = 1f;

            // Linear or Exponential fade
            if (fadeType == FadeType.Linear)
                fade = 1f - Vector3.Distance (bombPos, fragPos) / range;

            // Exponential fade
            else if (fadeType == FadeType.Exponential)
            {
                fade =  1f - Vector3.Distance (bombPos, fragPos) / range;
                fade *= fade;
            }
            
            // By curve
            else if (fadeType == FadeType.ByCurve)
            {
                fade = curve.Evaluate (Vector3.Distance (bombPos, fragPos) / range);;
            }

            // Cap fade
            if (fade < 0.01f)
                fade = 0;

            return fade;
        }

        // Get explosion vector from explosion position to projectile center of mass
        Vector3 Vector (Projectile projectile)
        {
            Vector3 vector = Vector3.up;

            // Spherical range
            if (rangeType == RangeType.Spherical)
                vector = Vector3.Normalize (projectile.positionPivot - explPosition);

            // Cylindrical range
            //else if (rangeType == RangeType.Cylindrical)
            //{
            //    Vector3 lineDir = transForm.InverseTransformDirection(Vector3.up);
            //    lineDir = Vector3.up;
            //    lineDir.Normalize();
            //    var vec = projectile.positionPivot - explPosition;
            //    var dot = Vector3.Dot(vec, lineDir);
            //    Vector3 nearestPointOnLine = explPosition + lineDir * dot;
            //    vector = Vector3.Normalize(projectile.positionPivot - nearestPointOnLine);
            //}

            return vector;
        }
    }
}