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

namespace RealTimeGraphEx.ReachGraphs
{
    public class RealTimeGraphExReachLineErase : RealTimeGraphExReachLineScroll, INotifyPropertyChanged
    {
        #region Cross Thread Fields

        protected Brush _markerColor;
        protected bool _showMarker;
        protected bool _endReached;
        protected int _currentReplaceIndex;
        protected bool _enableMarkerPosition;
        protected double lastVirtualValue;
        protected Rectangle marker;

        #endregion

        #region Properties

        /// <summary>
        /// Gets or sets the graph marker color.
        /// </summary>
        public Brush MarkerBrush
        {
            get { return (Brush)GetValue(MarkerBrushProperty); }
            set { SetValue(MarkerBrushProperty, value); }
        }
        public static readonly DependencyProperty MarkerBrushProperty =
            DependencyProperty.Register("MarkerBrush", typeof(Brush), typeof(RealTimeGraphExReachLineErase), new PropertyMetadata(Brushes.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(RealTimeGraphExReachLineErase), 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(RealTimeGraphExReachLineErase), 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 RealTimeGraphExReachLineErase()
            : base()
        {

        }

        #endregion

        #region Override Method

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

            _currentReplaceIndex = 0;
            _endReached = false;

            this.Dispatcher.Invoke(() =>
            {
                marker.RenderTransform = new TranslateTransform(0, 0);
            });
        }

        protected override void Initialize()
        {
            base.Initialize();
            marker = new Rectangle() { VerticalAlignment = System.Windows.VerticalAlignment.Stretch, Width = 1, Fill = MarkerBrush, HorizontalAlignment = System.Windows.HorizontalAlignment.Left, Margin = new Thickness(-2, 0, 0, 0) };

            if (!gridLinesAndImageWrapperGrid.Children.Contains(marker))
            {
                gridLinesAndImageWrapperGrid.Children.Add(marker);
            }
        }

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

            this.Dispatcher.Invoke(() =>
            {

                _markerColor = MarkerBrush;
                _showMarker = ShowMarker;
                _enableMarkerPosition = EnableMarkerPosition;

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

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

                if (!_isPaused)
                {
                    for (int i = 0; i < points.Count; i++)
                    {
                        double value = points[i];
                        lastVirtualValue = value;

                        if (xValueCounter <= _width)
                        {
                            if (!_endReached)
                            {
                                graphPolygon.Add(value);
                                xValueCounter += _scaleFactor;
                            }
                            else
                            {
                                graphPolygon.Replace(value, _currentReplaceIndex++);
                                xValueCounter += _scaleFactor;

                                if (_currentReplaceIndex > graphPolygon.Count - 1)
                                {
                                    xValueCounter = 0;
                                    _currentReplaceIndex = 0;
                                }
                            }
                        }
                        else
                        {
                            _endReached = true;
                            xValueCounter = 0;
                            graphPolygon.Replace(value, _currentReplaceIndex++);
                            xValueCounter += _scaleFactor;
                        }
                    }
                }

                updateCounter++;

                if (updateCounter >= 1 && !_isPaused)
                {
                    updateCounter = 0;
                    if (!_disableRendering)
                    {
                        OnDrawVisuals();
                    }
                }
            }
        }

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

            double scale = GetPolygonScaleFactor();

            this.Dispatcher.Invoke(() =>
            {
                double x = ((_currentReplaceIndex * scale));
                marker.RenderTransform = new TranslateTransform((x) - 2, 0);
            });
        }

        #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
    }
}