using System;
using System.Collections.Generic;
using System.ComponentModel;
using System.Diagnostics;
using System.Linq;
using System.Text;
using System.Threading.Tasks;
using System.Windows;
using System.Windows.Media;
using System.Windows.Media.Imaging;

namespace RealTimeGraphEx.FastGraphs
{
    public class RealTimeGraphExLineErase : RealTimeGraphExLineScroll, INotifyPropertyChanged
    {
        #region Cross Thread Fields

        protected Color _markerColor;
        protected bool _showMarker;
        protected bool _endReached;
        protected int _currentReplaceIndex;
        protected bool _enableMarkerPosition;
        protected double lastVirtualValue;
        protected int lastMaxPoints;

        #endregion

        #region Properties

        /// <summary>
        /// Gets or sets the graph marker color.
        /// </summary>
        public Color MarkerColor
        {
            get { return (Color)GetValue(MarkerColorProperty); }
            set { SetValue(MarkerColorProperty, value); }
        }
        public static readonly DependencyProperty MarkerColorProperty =
            DependencyProperty.Register("MarkerBrush", typeof(Color), typeof(RealTimeGraphExLineErase), new PropertyMetadata(Colors.Red, new PropertyChangedCallback(CrossModelChanged)));

        /// <summary>
        /// Gets or sets whether to display the marker on the graph.
        /// </summary>
        public bool ShowMarker
        {
            get { return (bool)GetValue(ShowMarkerProperty); }
            set { SetValue(ShowMarkerProperty, value); }
        }
        public static readonly DependencyProperty ShowMarkerProperty =
            DependencyProperty.Register("ShowMarker", typeof(bool), typeof(RealTimeGraphExLineErase), new PropertyMetadata(true, new PropertyChangedCallback(CrossModelChanged)));

        /// <summary>
        /// Gets or sets a value indicating whether to enable the MarkerPosition property to be updated. (Affects performance).
        /// </summary>
        public bool EnableMarkerPosition
        {
            get { return (bool)GetValue(EnableMarkerPositionProperty); }
            set { SetValue(EnableMarkerPositionProperty, value); }
        }
        public static readonly DependencyProperty EnableMarkerPositionProperty =
            DependencyProperty.Register("EnableMarkerPosition", typeof(bool), typeof(RealTimeGraphExLineErase), new PropertyMetadata(false, new PropertyChangedCallback(CrossModelChanged)));

        /// <summary>
        /// Gets the current marker position on the graph.
        /// </summary>
        private Point markerPosition;
        public Point MarkerPosition
        {
            private get { return markerPosition; }
            set { markerPosition = value; RaisePropertyChanged("MarkerPosition"); }
        }

        #endregion

        #region Constructors

        public RealTimeGraphExLineErase()
            : base()
        {

        }

        #endregion

        #region Override Method

        protected override void OnSetCrossThreadFields()
        {
            base.OnSetCrossThreadFields();

            this.Dispatcher.Invoke(() =>
            {
                _markerColor = MarkerColor;
                _showMarker = ShowMarker;
                _enableMarkerPosition = EnableMarkerPosition;

                if (lastMaxPoints > _maxPoints && graphPolygon.Count > (lastMaxPoints - _maxPoints))
                {
                    graphPolygon.RemoveFromStart(lastMaxPoints - _maxPoints);
                }

                lastMaxPoints = _maxPoints;

            }, System.Windows.Threading.DispatcherPriority.Send);
        }

        protected internal override void OnRenderGraph()
        {
            if (_graphController != null && _graphController.dataSeries != null && _graphController.dataSeries.Points != null && _graphController.dataSeries.Points.Count > 0 && _width > 1 && _height > 1)
            {
                var points = _graphController.dataSeries.Points.GetAndClearAllPoints();

                if (_useAutoRange && points.Count > 0)
                {
                    Dispatcher.Invoke(() =>
                    {
                        Maximum = points.Concat(graphPolygon.GetPoints()).Max();
                        Minimum = points.Concat(graphPolygon.GetPoints()).Min();
                    });
                }

                if (!_isPaused)
                {

                    for (int i = 0; i < points.Count; i++) //Match
                    {
                        double value = points[i];
                        NormalizeValue(ref value);
                        lastVirtualValue = value;

                        if (graphPolygon.Count > _maxPoints)
                        {
                            graphPolygon.Replace(value, _currentReplaceIndex++);

                            for (int k = 0; k < _markers.Count; k++)
                            {
                                if (_markers[k] == _currentReplaceIndex)
                                {
                                    _markers.RemoveAt(k);
                                    k--;
                                }
                            }
                        }
                        else
                        {
                            graphPolygon.Add(value);
                        }

                        xValueCounter += _scaleFactor;

                        if (_currentReplaceIndex == graphPolygon.Count - 1)
                        {
                            xValueCounter = 0;
                            _currentReplaceIndex = 0;
                        }
                    }
                }

                updateCounter++;

                if (updateCounter >= 1)
                {
                    updateCounter = 0;

                    if (!_disableRendering)
                    {
                        WriteableBitmap bmp = BitmapFactory.New((int)_mainWidth, (int)_mainHeight);
                        bmp.Clear(Colors.Transparent);

                        OnDrawVisuals(bmp);

                        bmp.Freeze();

                        img.Dispatcher.BeginInvoke(new Action(() =>
                        {
                            img.Source = bmp;
                        }), System.Windows.Threading.DispatcherPriority.Send);
                    }
                }
            }
        }

        protected override void OnDrawVisuals(WriteableBitmap bmp)
        {
            if (_graphController == null) return;

            Color stroke = _graphController.dataSeries.GetStrokeColor() != null ? _graphController.dataSeries.GetStrokeColor().Value : _stroke;
            Color fill = _graphController.dataSeries.GetFillColor() != null ? _graphController.dataSeries.GetFillColor().Value : _fill;
            double scale = GetPolygonScaleFactor();
            double currentWidth = _endReached ? _width : xValueCounter;


            if (_fillGraph) //Fill Graph
            {
                bmp.FillPolygon(graphPolygon.ToPolygonPointsFill(_offSetX, _offSetY, _mainWidth, _mainHeight, scale, ConvertYToImageYFliped), fill);
            }

            DrawPolyline(bmp, graphPolygon.ToPolygonPoints(_offSetX, _offSetY, scale, ConvertYToImageYFliped), stroke);


            //Draw marker
            if (_showMarker)
            {
                if (_currentReplaceIndex > 0)
                {
                    try
                    {

                        double x = (((_currentReplaceIndex - 1) * scale) + _offSetX);
                        bmp.DrawLine((int)x, 0, (int)x, (int)_mainHeight, _markerColor);
                    }
                    catch
                    {
                        Debug.WriteLine("[RealTimeGraphExLineErase] [OnDrawVisuals] Error on drawing marker!");
                    }
                }
            }

            for (int j = 0; j < _markers.Count; j++)
            {
                int x = (int)(((_markers[j] - 1) * scale) + _offSetX);
                bmp.DrawLine(x, 0, x, (int)_mainHeight, Colors.Silver);
            }

            if (_enableMarkerPosition)
            {
                MarkerPosition = new Point((_currentReplaceIndex * scale) + _offSetX, ConvertYToImageYFliped(lastVirtualValue) + _offSetY);
            }
        }

        protected override void OnClearGraph()
        {
            base.OnClearGraph();

            _currentReplaceIndex = 0;
            _endReached = false;
            MarkerPosition = new Point(0, 0);
        }

        protected override void OnPushMarker()
        {
            if (_currentReplaceIndex != 0)
            {
                _markers.Add(_currentReplaceIndex);
            }
        }

        #endregion

        #region INotifyPropertyChanged Members

        public event PropertyChangedEventHandler PropertyChanged;

        public void RaisePropertyChanged(String propName)
        {
            this.Dispatcher.Invoke(() =>
            {

                if (PropertyChanged != null) PropertyChanged(this, new PropertyChangedEventArgs(propName));

            });
        }

        #endregion
    }
}