using netDxf.Entities;
using System;
using System.Collections.Generic;
using System.Linq;
using System.Text;
using System.Threading.Tasks;
using System.Windows;
using System.Windows.Media;
using WpfShapes = System.Windows.Shapes;
using DxfLine = netDxf.Entities.Line;
using WpfLine = System.Windows.Shapes.Line;
using DxfEllipse = netDxf.Entities.Ellipse;
using WpfEllipse = System.Windows.Shapes.Ellipse;
using WpfPoint = System.Windows.Point;

namespace TeamAAS_VP.DxfModule
{
    public class GraphicsRenderer
    {
        private const double DefaultStrokeThickness = 1.0;

        public static List<UIElement> RenderEntity(EntityObject entity, double scale = 1.0)
        {
            var elements = new List<UIElement>();

            switch (entity)
            {
                case DxfLine line:
                    elements.Add(RenderLine(line, scale));
                    break;
                case Circle circle:
                    elements.Add(RenderCircle(circle, scale));
                    break;
                case Arc arc:
                    elements.Add(RenderArc(arc, scale));
                    break;
                case netDxf.Entities.Point point:
                    elements.Add(RenderPoint(point, scale));
                    break;
                case Text text:
                    elements.Add(RenderText(text, scale));
                    break;
                case MText mtext:
                    elements.Add(RenderMText(mtext, scale));
                    break;
                case Spline spline:
                    elements.AddRange(RenderSpline(spline, scale));
                    break;
            }

            return elements;
        }

        private static UIElement RenderLine(DxfLine line, double scale)
        {
            var wpfLine = new WpfLine
            {
                X1 = line.StartPoint.X * scale,
                Y1 = -line.StartPoint.Y * scale, // Flip Y axis
                X2 = line.EndPoint.X * scale,
                Y2 = -line.EndPoint.Y * scale,
                Stroke = new SolidColorBrush(GetColor(line.Color)),
                StrokeThickness = DefaultStrokeThickness,
                Tag = line // Store original entity
            };
            return wpfLine;
        }

        private static UIElement RenderCircle(Circle circle, double scale)
        {
            var wpfEllipse = new WpfEllipse
            {
                Width = circle.Radius * 2 * scale,
                Height = circle.Radius * 2 * scale,
                Stroke = new SolidColorBrush(GetColor(circle.Color)),
                StrokeThickness = DefaultStrokeThickness,
                Fill = Brushes.Transparent,
                Tag = circle
            };

            System.Windows.Controls.Canvas.SetLeft(wpfEllipse, (circle.Center.X - circle.Radius) * scale);
            System.Windows.Controls.Canvas.SetTop(wpfEllipse, (-circle.Center.Y - circle.Radius) * scale);

            return wpfEllipse;
        }

        private static UIElement RenderArc(Arc arc, double scale)
        {
            var path = new WpfShapes.Path
            {
                Stroke = new SolidColorBrush(GetColor(arc.Color)),
                StrokeThickness = DefaultStrokeThickness,
                Fill = Brushes.Transparent,
                Tag = arc
            };

            var geometry = new PathGeometry();
            var figure = new PathFigure();

            // Calculate start and end points
            double startAngleRad = arc.StartAngle * Math.PI / 180.0;
            double endAngleRad = arc.EndAngle * Math.PI / 180.0;

            double startX = (arc.Center.X + arc.Radius * Math.Cos(startAngleRad)) * scale;
            double startY = (-arc.Center.Y - arc.Radius * Math.Sin(startAngleRad)) * scale;
            double endX = (arc.Center.X + arc.Radius * Math.Cos(endAngleRad)) * scale;
            double endY = (-arc.Center.Y - arc.Radius * Math.Sin(endAngleRad)) * scale;

            figure.StartPoint = new WpfPoint(startX, startY);

            var arcSegment = new ArcSegment
            {
                Point = new WpfPoint(endX, endY),
                Size = new System.Windows.Size(arc.Radius * scale, arc.Radius * scale),
                SweepDirection = SweepDirection.Counterclockwise,
                IsLargeArc = Math.Abs(arc.EndAngle - arc.StartAngle) > 180
            };

            figure.Segments.Add(arcSegment);
            geometry.Figures.Add(figure);
            path.Data = geometry;

            return path;
        }

        private static List<UIElement> RenderSpline(Spline spline, double scale)
        {
            var elements = new List<UIElement>();

            // Approximate spline with lines using control points
            var controlPoints = new List<netDxf.Vector3>(spline.ControlPoints);
            if (controlPoints.Count < 2)
                return elements;

            for (int i = 0; i < controlPoints.Count - 1; i++)
            {
                var p1 = controlPoints[i];
                var p2 = controlPoints[i + 1];

                var line = new WpfLine
                {
                    X1 = p1.X * scale,
                    Y1 = -p1.Y * scale,
                    X2 = p2.X * scale,
                    Y2 = -p2.Y * scale,
                    Stroke = new SolidColorBrush(GetColor(spline.Color)),
                    StrokeThickness = DefaultStrokeThickness,
                    Tag = spline
                };
                elements.Add(line);
            }

            return elements;
        }

        private static UIElement RenderPoint(netDxf.Entities.Point point, double scale)
        {
            var ellipse = new WpfEllipse
            {
                Width = 3,
                Height = 3,
                Fill = new SolidColorBrush(GetColor(point.Color)),
                Tag = point
            };

            System.Windows.Controls.Canvas.SetLeft(ellipse, point.Position.X * scale - 1.5);
            System.Windows.Controls.Canvas.SetTop(ellipse, -point.Position.Y * scale - 1.5);

            return ellipse;
        }

        private static UIElement RenderText(Text text, double scale)
        {
            var textBlock = new System.Windows.Controls.TextBlock
            {
                Text = text.Value,
                Foreground = new SolidColorBrush(GetColor(text.Color)),
                FontSize = text.Height * scale,
                Tag = text
            };

            System.Windows.Controls.Canvas.SetLeft(textBlock, text.Position.X * scale);
            System.Windows.Controls.Canvas.SetTop(textBlock, -text.Position.Y * scale);

            return textBlock;
        }

        private static UIElement RenderMText(MText mtext, double scale)
        {
            var textBlock = new System.Windows.Controls.TextBlock
            {
                Text = mtext.Value,
                Foreground = new SolidColorBrush(GetColor(mtext.Color)),
                FontSize = mtext.Height * scale,
                Tag = mtext
            };

            System.Windows.Controls.Canvas.SetLeft(textBlock, mtext.Position.X * scale);
            System.Windows.Controls.Canvas.SetTop(textBlock, -mtext.Position.Y * scale);

            return textBlock;
        }

        private static Color GetColor(netDxf.AciColor aciColor)
        {
            // Convert DXF AciColor to WPF Color
            if (aciColor.IsByLayer || aciColor.IsByBlock)
                return Colors.White;

            var rgb = aciColor.ToColor();
            return Color.FromRgb(rgb.R, rgb.G, rgb.B);
        }

        public static void HighlightElement(UIElement element, bool isSelected)
        {
            if (element is WpfShapes.Shape shape)
            {
                if (isSelected)
                {
                    shape.Stroke = Brushes.Yellow;
                    shape.StrokeThickness = 2.0;
                }
                else
                {
                    // Restore original color from entity
                    if (shape.Tag is EntityObject entity)
                    {
                        shape.Stroke = new SolidColorBrush(GetColor(entity.Color));
                        shape.StrokeThickness = DefaultStrokeThickness;
                    }
                }
            }
            else if (element is System.Windows.Controls.TextBlock textBlock)
            {
                if (isSelected)
                {
                    textBlock.Foreground = Brushes.Yellow;
                }
                else
                {
                    if (textBlock.Tag is Text text)
                    {
                        textBlock.Foreground = new SolidColorBrush(GetColor(text.Color));
                    }
                    else if (textBlock.Tag is MText mtext)
                    {
                        textBlock.Foreground = new SolidColorBrush(GetColor(mtext.Color));
                    }
                }
            }
        }
    }
}