using System;
using System.Collections;
using System.Collections.Generic;
using Invector.vCharacterController.AI;
using PixelCrushers.DialogueSystem;
using UnityEngine;
using UnityEngine.Events;
using UnityEngine.UI;
using Random = UnityEngine.Random;

namespace Beyond
{
    public class WonderingShadow : MonoBehaviour
    {
        public enum Mode
        {
            DESTROY_ON_TARGET,
            DESTROY_WHEN_NEAR,
            WONDER
        }

        public enum State
        {
            STARTING,
            MOVING,
            STOPPING,
            IDLE,
            GONE
        };

        [Serializable]
        public class ShadowData
        {
            public GameObject objectToSpawn;
            public float spawnedObjectYOffset = 0.1f;
            public Mode mode = Mode.DESTROY_WHEN_NEAR;
            public float distanceToDestroy = 7f;
            public LayerMask spawnedObjectRayMask = ~0;
            public Vector3 targetPosition;
            public UnityEvent<GameObject> OnDead;
        }

        public ShadowData m_shadowData = new ShadowData();

        public UnityEvent<State> m_OnStateChanged = new UnityEvent<State>();
        public GameObject m_endEffect;
        public float m_endEffectDestroyDelay = 7f;

        private State m_state;
        private const float MinDistance = 0.15f;

        //   public float Distance = 30;
        public float Speed = 1;

        public float TimeDelay = 0;
        public float m_StartStopDelay = 1f;
        public float RandomMoveRadius = 0;
        public float RandomMoveSpeedScale = 0;

        private Vector3 startPosition;
        private Vector3 startPositionLocal;
        private Transform t;
        private Vector3 oldPos;

        private Quaternion startQuaternion;

        //private float currentSpeed;
        private float currentDelay;

        private bool isInitialized;
        private int dropFirstFrameForFixUnityBugWithParticles = 3;
        private Vector3 randomTimeOffset;
        private float m_timer;
        public ParticleSystem[] m_particlesToReset;
        private ShadowArea m_shadowArea;

        public void ResetParticles()
        {
            foreach (ParticleSystem p in m_particlesToReset)
            {
                p.Clear();
                p.time = 0;
                p.Simulate(0, true, true);
                p.Play();
            }
        }

        private void Start()
        {
            t = transform;
            SetState(State.STARTING);
            m_shadowArea = gameObject.FindComponentUpHierarchy<ShadowArea>();
            Initialize(false);
        }

        private void Initialize(bool setTarget)
        {
            if (setTarget)
            {
                if (m_shadowArea != null)
                {
                    m_shadowData.targetPosition = m_shadowArea.GetRandomPosition();
                }
                else
                {
                    //if there is no area, just come back to starting location
                    m_shadowData.targetPosition = startPosition;
                }
            }

            startQuaternion = t.rotation;
            startPositionLocal = t.localPosition;
            startPosition = t.position;
            oldPos = startPosition;

            //currentSpeed = Speed;
            currentDelay = 0;
            //dropFirstFrameForFixUnityBugWithParticles = 3;
            randomTimeOffset = Random.insideUnitSphere * 10;
            //isInitialized = true;
        }

        public void SpawnEndEffect()
        {
            if (m_endEffect == null)
                return;
            var instance = Instantiate(m_endEffect, transform.position, transform.rotation);
            Destroy(instance, m_endEffectDestroyDelay);
        }

        public void SpawnEndObject()
        {
            if (m_shadowData.objectToSpawn == null)
                return;
            Vector3 pos = transform.position;
            RaycastHit hit = new RaycastHit();
            if (Physics.Raycast(pos, Vector3.down, out hit, 100f, m_shadowData.spawnedObjectRayMask))
            {
                pos.y = hit.point.y + m_shadowData.spawnedObjectYOffset;
            }

            var rotation = Quaternion.LookRotation(transform.rotation * Vector3.forward, Vector3.up);
            var instance = Instantiate(m_shadowData.objectToSpawn, pos, rotation);
            var spawnedAI = instance.GetComponent<vControlAI>();
            if (spawnedAI)
            {
                spawnedAI.onDead.AddListener(OnKilled);
            }
            if (Player.Instance != null)
            {
                Vector3 toPlayer = Player.Instance.transform.position - pos;
                toPlayer.y = 0f;
                rotation = Quaternion.LookRotation(transform.rotation * toPlayer, Vector3.up);
                instance.transform.rotation = rotation;
            }
        }

        public void OnKilled(GameObject go)
        {
            m_shadowData.OnDead?.Invoke(go);
        }

        private void SetState(State state)
        {
            switch (state)
            {
                case State.IDLE:
                    break;

                case State.STARTING:
                    //t.position = m_area.GetRandomPosition();
                    //m_targetPosition = m_area.GetRandomPosition();
                    //ResetParticles();
                    //ActivateEffects(true);
                    // Initialize();

                    //Initialize();
                    //SetState(State.MOVING);
                    break;

                case State.STOPPING:
                    // SetState(State.STARTING);
                    break;

                case State.MOVING:
                    break;

                case State.GONE:
                    SpawnEndEffect();
                    SpawnEndObject();
                    // Destroy(gameObject);
                    gameObject.SetActive(false);
                    break;
            }

            m_state = state;
            m_timer = 0f;
            m_OnStateChanged?.Invoke(state);
        }

        private void Update()
        {
            switch (m_state)
            {
                case State.MOVING:
                    if (dropFirstFrameForFixUnityBugWithParticles <= 0)
                    {
                        UpdateWorldPosition();
                    }
                    else
                    {
                        dropFirstFrameForFixUnityBugWithParticles--;
                    }

                    break;

                case State.STARTING:
                    if (m_timer > m_StartStopDelay)
                    {
                        SetState(State.MOVING);
                    }

                    break;

                case State.STOPPING:
                    if (m_timer > m_StartStopDelay)
                    {
                        //ResetParticles();
                        //ActivateEffects(false);
                        if (m_shadowData.mode != Mode.DESTROY_ON_TARGET)
                        {
                            Initialize(true);
                            SetState(State.STARTING);
                        }
                        else
                        {
                            SetState(State.GONE);
                        }
                    }

                    break;

                case State.IDLE:
                    break;
            }

            m_timer += Time.deltaTime;
        }

        /*
                private void LateUpdate()
                {
                    if (dropFirstFrameForFixUnityBugWithParticles > 0)
                    {
                        Initialize();
                    }
                }
        */

        private void UpdateWorldPosition()
        {
            currentDelay += Time.deltaTime;
            if (currentDelay < TimeDelay)
                return;

            Vector3 randomOffset = Vector3.zero;
            if (RandomMoveRadius > 0)
            {
                randomOffset = GetRadiusRandomVector() * RandomMoveRadius;
                var fade = Vector3.Distance(t.position, m_shadowData.targetPosition) /
                           Vector3.Distance(startPosition, m_shadowData.targetPosition);
                randomOffset *= fade;
            }

            var frameMoveOffset = Vector3.zero;
            var frameMoveOffsetWorld = Vector3.zero;
            //if (!isCollided && !isOutDistance)
            {
                //currentSpeed = Mathf.Clamp(currentSpeed - Speed*Dampeen*Time.deltaTime, MinSpeed, Speed);
                if (m_shadowData.targetPosition == null)
                {
                    var currentForwardVector = (Vector3.forward + randomOffset) * Speed * Time.deltaTime;
                    frameMoveOffset = t.localRotation * currentForwardVector;
                    frameMoveOffsetWorld = startQuaternion * currentForwardVector;
                }
                else
                {
                    var forwardVec = (m_shadowData.targetPosition - t.position).normalized;
                    var currentForwardVector = (forwardVec + randomOffset) * Speed * Time.deltaTime;
                    frameMoveOffset = currentForwardVector;
                    frameMoveOffsetWorld = currentForwardVector;
                }
            }

            var currentDistance = (t.localPosition + frameMoveOffset - startPositionLocal).magnitude;
            var targetDistance = (t.position + frameMoveOffset - m_shadowData.targetPosition).magnitude;
            Debug.DrawRay(t.position, frameMoveOffsetWorld.normalized * (currentDistance));

            if (targetDistance < MinDistance + frameMoveOffset.magnitude)
            {
                SetState((State.STOPPING));
            }
            else if (m_shadowData.mode == Mode.DESTROY_WHEN_NEAR)
            {
                if (Player.Instance == null)
                    return;
                var dist = Vector3.Distance(Player.Instance.transform.position, t.position);
                if (dist < m_shadowData.distanceToDestroy)
                {
                    SetState(State.GONE);
                }
            }

            t.position = oldPos + frameMoveOffsetWorld;
            oldPos = t.position;
        }

        private Vector3 GetRadiusRandomVector()
        {
            var x = Time.time * RandomMoveSpeedScale + randomTimeOffset.x;
            var vecX = Mathf.Sin(x / 7 + Mathf.Cos(x / 2)) * Mathf.Cos(x / 5 + Mathf.Sin(x));

            x = Time.time * RandomMoveSpeedScale + randomTimeOffset.y;
            var vecY = Mathf.Cos(x / 8 + Mathf.Sin(x / 2)) * Mathf.Sin(Mathf.Sin(x / 1.2f) + x * 1.2f);

            x = Time.time * RandomMoveSpeedScale + randomTimeOffset.z;
            var vecZ = Mathf.Cos(x * 0.7f + Mathf.Cos(x * 0.5f)) * Mathf.Cos(Mathf.Sin(x * 0.8f) + x * 0.3f);

            return new Vector3(vecX, vecY, vecZ);
        }
    }
}