using System.Diagnostics;
using System.Collections;
using System.Collections.Generic;
using System;
using Godot;


namespace Rokojori
{  
  [Tool]
  [GlobalClass]
  public partial class TimeLineManager:RJTimeLineManager
  {    
    [Export]
    public RJTimeLine[] timeLines;

    [Export]
    public RJTimeLine engineTimeScale;

    [Export]
    public RJTimeLine realTimeTimeLine;

    [Export]
    public bool computeRealtimeWithEngineDelta;


    List<TimeLineRunner> _runners = new List<TimeLineRunner>();

    int _idCounter = 0;    
    bool _initialized = false;

    public override void _Ready()
    {
      Initialize();
    }

    float _lastUpdate = 0;
    DateTime lastUpdated = DateTime.Now;
    float _estimatedDelta = 0;
    float _estimatedDeltaFilter = 0.9f;
    float _unscaledDelta = 0;
    double _lastRealtimePosition = 0;
    double _realtimePosition = 0;

    float _lastTimeScale = 1;

    public override void _Process( double delta )
    {       
      UpdateRealTime( delta );

      if ( engineTimeScale != null )
      {
        Engine.TimeScale = GetModulatedSpeed( engineTimeScale );        
      }
      
      _runners.ForEach( r => r.UpdateTimeLine( unscaledTimeDelta, this ) );
      
    }

    public void Modulate( RJTimeLine timeline, AnimationCurve c, Action<bool> onReady )
    {
      var runner = GetRunner( GetTimeLineIndex( timeline ) );
      runner.Modulate( c, onReady );
    }

    void UpdateRealTime( double engineDelta )
    {
      
      var now = DateTime.Now;
      var unscaled = (float) ( ( now - lastUpdated ).TotalSeconds );
      lastUpdated = now;

      if ( unscaled < 1f/20f )
      {
        _estimatedDelta += _estimatedDeltaFilter * ( unscaled - _estimatedDelta );
      }      

      if ( computeRealtimeWithEngineDelta )
      {
        _unscaledDelta = (float)(  Engine.TimeScale == 0 ? _estimatedDelta : ( engineDelta / Engine.TimeScale ) );
      }
      else
      {
        _unscaledDelta = _estimatedDelta;
      }
      

      _lastRealtimePosition = _realtimePosition;
      _realtimePosition += _unscaledDelta;      
    }

    public float unscaledTimeDelta => _unscaledDelta;
    public double realtime => _realtimePosition;


    void Initialize()
    {
      if ( _initialized )
      {
        return;
      }

      _initialized = true;
      _runners = Lists.Map( timeLines, tl => new TimeLineRunner( tl ) );
    }

    TimeLineRunner GetRunner( int index )
    {
      if ( index < 0 || index >= _runners.Count )
      {
        return null ;
      }

      return _runners[ index ];
    }

    public override int CreateID()
    {
      _idCounter ++;
      return _idCounter;
    }

    public static float GetPosition( RJTimeLine timeLine )
    {
      var manager = Unique<TimeLineManager>.Get();
      
      if ( manager == null )
      {
        return Time.GetTicksMsec() / 1000f;
      }

      var index = Arrays.IndexOf( manager.timeLines, timeLine );

      index = Mathf.Max( index, 0 );

      return (float) manager.GetPosition( index );
    }


    public static float GetPhase( RJTimeLine timeLine, float duration, float offset = 0 )
    {
      var time = GetPosition( timeLine ) + offset;

      return ( time % duration ) / duration;
    }

    public static float GetRangePhase( RJTimeLine timeLine, float start, float end )
    {
      var time = GetPosition( timeLine );
      var normalized = MathX.Normalize( time, start, end );
      return normalized;
    }
  

    

    public override void ScheduleEvent( int timeLineIndex, double position, int callbackID, bool isPersistent )
    {
      var runner = _runners[ timeLineIndex ];    
      runner.ScheduleEvent( position, callbackID, isPersistent );
    }  

    public override void ScheduleSpan( int timeLineIndex, double start, double end, int callbackID, bool isPersistent )
    {
      var runner = _runners[ timeLineIndex ];    
      runner.ScheduleSpan( start, end, callbackID, isPersistent );
    }

    public override double GetLastPosition( int timeLineIndex )
    {
      var runner = GetRunner( timeLineIndex ); if ( runner == null ){ return 0; } 

      return runner.lastPosition;
    }

    public override double GetPosition( int timeLineIndex )
    {
      var runner = GetRunner( timeLineIndex ); if ( runner == null ){ return 0; } 
      return runner.position;
    }

    public override void SetPosition( int timeLineIndex, double position )
    {
      var runner = GetRunner( timeLineIndex ); if ( runner == null ){ return; } 
      runner.position = position;
    }

    public override double GetSpeed( int timeLineIndex )
    {
      var runner = GetRunner( timeLineIndex ); if ( runner == null ){ return 1; } 
      return runner.speed;
    }

    public float GetModulatedSpeed( RJTimeLine timeline )
    {
      var timeLineIndex = GetTimeLineIndex( timeline );
      var runner = GetRunner( timeLineIndex ); if ( runner == null ){ return 1; } 
      return runner.modulatedSpeed;
    }

    public float GetSpeed( RJTimeLine timeline )
    {
      return (float) GetSpeed( GetTimeLineIndex( timeline ) );
    }

    public override void SetSpeed( int timeLineIndex, double speed )
    {
      var runner = GetRunner( timeLineIndex ); if ( runner == null ){ return; } 
      runner.speed = speed;
    }

    public void SetSpeed( RJTimeLine timeline, double speed )
    {
      SetSpeed( GetTimeLineIndex( timeline ), speed );
    }



    public override bool GetPlayState( int timeLineIndex )
    {
      var runner = GetRunner( timeLineIndex ); if ( runner == null ){ return false; } 
      return runner.playing;
    }

    public override void SetPlayState( int timeLineIndex, bool isPlaying )
    {
      var runner = GetRunner( timeLineIndex ); if ( runner == null ){ return; } 
      runner.playing = isPlaying;
    }
  }
}