using System;
using System.Collections;
using System.Data;
using System.Threading;
using BlueWest.Collections;
using BlueWest.Coroutines;
using BlueWest.Tools;

namespace BlueWest.Core.ComponentSystem
{

    public enum ArtefactFrequency
    {
        T120Hz,
        T60Hz, 
        T30Hz,
        T20Hz,
        T10Hz,
        T4Hz  ,  
        T3Hz ,   
        T2Hz ,   
        T1Hz
    }

    public class Artefact
    {

        public Artefact()
        {
            _autoTickTimer = new TimerTick();
            _autoTickTimer.Reset();
            _maximumElapsedTime = TimeSpan.FromMilliseconds(500.0);
        }
        // Time Management

        private readonly TimeSpan _maximumElapsedTime;
        private TimeSpan _accumulatedElapsedGameTime;

        private TimeSpan TargetElapsedTime = TimeSpan.FromTicks(TimeSpan.TicksPerSecond / 30); // target elapsed time is by default 250Hz

        private readonly TimerTick _autoTickTimer;
        private TimeSpan accumulatedElapsedGameTime;

        private FastDictionary<ArtefactFrequency, int> behaviorConfigType =
            new FastDictionary<ArtefactFrequency, int>(10);

        
        private readonly FastList<IEnumerator> _coroutines = new FastList<IEnumerator>(10000);
        private bool? _prevVisibility;
        // Mini ECS
        protected  EventManager _eventManager;


        private bool _startCalled;

        internal VisibilityHandler _visibilityHandler = new VisibilityHandler();
        
        internal FastList<Component> _components = new FastList<Component>(10);
        
        private int _componentsCount = 0;

        private readonly ArtefactFrequency BehaviorType;

        
        // OLD STUFF
    
        
        protected internal ArtefactFrequency Frequency;

        protected internal bool IsActive { get { return _visibilityHandler.IsVisible; } set { SetActive(value); } }
         /// <summary>
        ///    Initial setup of the entity. Triggers Awake method if the node is visible
        ///    and triggers an visibility change event. 
        /// </summary>
        public void SetupEntity(EventManager eventManager)
         {
             _eventManager = eventManager;
             
            switch (BehaviorType)
            {
            
                case ArtefactFrequency.T1Hz:
                    TargetElapsedTime = TimeSpan.FromTicks(TimeSpan.TicksPerSecond / 1);
                    break;
                case ArtefactFrequency.T2Hz:
                    TargetElapsedTime = TimeSpan.FromTicks(TimeSpan.TicksPerSecond / 2);
                    break;
                case ArtefactFrequency.T3Hz:
                    TargetElapsedTime = TimeSpan.FromTicks(TimeSpan.TicksPerSecond / 3);
                    break;
                case ArtefactFrequency.T4Hz:
                    TargetElapsedTime = TimeSpan.FromTicks(TimeSpan.TicksPerSecond / 4);
                    break;
                case ArtefactFrequency.T10Hz:
                    TargetElapsedTime = TimeSpan.FromTicks(TimeSpan.TicksPerSecond / 10);
                    break;
                case ArtefactFrequency.T20Hz:
                    TargetElapsedTime = TimeSpan.FromTicks(TimeSpan.TicksPerSecond / 20);
                    break;
                case ArtefactFrequency.T30Hz:
                    TargetElapsedTime = TimeSpan.FromTicks(TimeSpan.TicksPerSecond / 30);
                    break;
                case ArtefactFrequency.T60Hz:
                    TargetElapsedTime = TimeSpan.FromTicks(TimeSpan.TicksPerSecond / 60);
                    break;
                case ArtefactFrequency.T120Hz:
                    TargetElapsedTime = TimeSpan.FromTicks(TimeSpan.TicksPerSecond / 120);
                    break;
                default:
                    throw new EvaluateException(
                        $"BehaviorType of class  can't be null. Please assign it in the Constructor.");
             
            }

            if (!_visibilityHandler.IsVisible) return;

            Awake();

            OnVisibilityChange();

            if (!_visibilityHandler.IsVisible) return;

            if (!_startCalled)
            {
                _startCalled = true;

                Start();

            }
        }
        public void AddComponent<T>() where T : Component
        {
            var component = Activator.CreateInstance(typeof(T), _eventManager) as Component;
            _components.Add(component);
            _componentsCount += 1;
            component.Start();
        }


        protected virtual void Awake()
        {
            
        }
        
        protected virtual void Start()
        {
            
        }
        
        public void ProcessComponents(double delta)
        {
            for (int i = 0; i < _components.Length; i++)
            {
                var component = _components.Buffer[i];
                component.EveryFrame(delta);
                component.HandleCoroutines();
            }
        }

        public void StartCoroutine(IEnumerator routine)
        {
            _coroutines.Add(routine);
        }

        public bool LoopEnabled = true;

        /// <summary>
        ///    Called every frame
        /// </summary>
        public void RunLoop()
        {
            RetryTick:

            if (!LoopEnabled) return;

            if (!_visibilityHandler.IsVisible) return;

            _autoTickTimer.Tick();

            var elapsedAdjustedTime = _autoTickTimer.ElapsedTimeWithPause;

            int updateCount = 1;

            // then make ElapsedAdjustedTime = TargetElapsedTime. We take the same internal rules as XNA
            if (Math.Abs(elapsedAdjustedTime.Ticks - TargetElapsedTime.Ticks) < (TargetElapsedTime.Ticks >> 6))
            {
                elapsedAdjustedTime = TargetElapsedTime;
            }

            // Update the accumulated time
            accumulatedElapsedGameTime += elapsedAdjustedTime;


            if (accumulatedElapsedGameTime < TargetElapsedTime)
            {
                var sleepTime = (TargetElapsedTime - accumulatedElapsedGameTime).TotalMilliseconds;
                if (sleepTime >= 2.0)
                {
                    System.Threading.Thread.Sleep(1);
                }

                goto RetryTick;
            }

            // We are going to call Update updateCount times, so we can subtract this from accumulated elapsed game time
            accumulatedElapsedGameTime =
                new TimeSpan(accumulatedElapsedGameTime.Ticks - (updateCount * TargetElapsedTime.Ticks));

            for (int i = 0; i < updateCount; i++)
            {
                double delta = TargetElapsedTime.TotalSeconds;
                Update(delta);
                ProcessComponents(delta);
            }

            if (!_visibilityHandler.IsVisible) return; // Added to avoid running after deactivating node

            HandleCoroutines();

            goto RetryTick;
        }

        protected virtual void Update(double delta)
        {
        }

        public void HandleCoroutines()
        {
            for (var i = 0; i < _coroutines.Length; i++)
            {
                var yielded = _coroutines.Buffer[i].Current is CustomYieldInstruction yielder && yielder.MoveNext();

                if (yielded || _coroutines.Buffer[i].MoveNext()) continue;
                _coroutines.RemoveAt(i);
                i--;
            }
        }
        /// <summary>
        ///    Trigger OnEnable and OnDisable methods regarding the current and previous visibility. 
        /// </summary>
        internal void OnVisibilityChange()
        {
            var curVisibility = _visibilityHandler.IsVisible;

            if (curVisibility == _prevVisibility) return;

            if (curVisibility) OnEnable();

            if (!curVisibility) OnDisable();

            _prevVisibility = curVisibility;
        }

        protected virtual void OnEnable()
        {
            
        }
        
        protected virtual void OnDisable()
        {
            
        }
        
        public void SetActive(bool status)
        {
            _visibilityHandler.SetVisibility(status);
            OnVisibilityChange();
        }

    }
}