using System.Windows;
using System.Windows.Controls;
using System.Windows.Input;
using System.Windows.Media;
using System.Windows.Shapes;

namespace ShapeDrawingApp
{
    public partial class MainWindow : Window
    {
        private enum DrawMode
        {
            None,
            Ellipse,
            Rectangle,
            Circle,
            Line
        }

        private DrawMode currentDrawMode = DrawMode.None;
        private Point startPoint;
        private Shape currentShape;

        public MainWindow()
        {
            InitializeComponent();
        }

        private void SetCurrentDrawMode(DrawMode mode)
        {
            currentDrawMode = mode;
            currentShape = null;
        }

        private void btnEllipse_Click(object sender, RoutedEventArgs e)
        {
            SetCurrentDrawMode(DrawMode.Ellipse);
        }

        private void btnRectangle_Click(object sender, RoutedEventArgs e)
        {
            SetCurrentDrawMode(DrawMode.Rectangle);
        }

        private void btnCircle_Click(object sender, RoutedEventArgs e)
        {
            SetCurrentDrawMode(DrawMode.Circle);
        }

        private void btnLine_Click(object sender, RoutedEventArgs e)
        {
            SetCurrentDrawMode(DrawMode.Line);
        }

        private void drawingCanvas_MouseDown(object sender, MouseButtonEventArgs e)
        {
            if (currentDrawMode != DrawMode.None)
            {
                startPoint = e.GetPosition(drawingCanvas);
                currentShape = CreateShape();
                drawingCanvas.Children.Add(currentShape);
            }
        }

        private void drawingCanvas_MouseUp(object sender, MouseButtonEventArgs e)
        {
            if (currentShape != null)
            {
                currentShape = null;
            }
        }

        private void drawingCanvas_MouseMove(object sender, MouseEventArgs e)
        {
            if (currentShape != null && e.LeftButton == MouseButtonState.Pressed)
            {
                Point currentPoint = e.GetPosition(drawingCanvas);
                UpdateShape(currentShape, startPoint, currentPoint);
            }
        }

        private Shape CreateShape()
        {
            Shape shape = null;
            switch (currentDrawMode)
            {
                case DrawMode.Ellipse:
                    shape = new Ellipse();
                    break;

                case DrawMode.Rectangle:
                    shape = new Rectangle();
                    break;

                case DrawMode.Circle:
                    shape = new Ellipse();
                    break;

                case DrawMode.Line:
                    shape = new Line();
                    break;
            }

            shape.Stroke = Brushes.Black;
            shape.StrokeThickness = 2;
            return shape;
        }

        private void UpdateShape(Shape shape, Point startPoint, Point endPoint)
        {
            if (shape == null)
                return;

            if (currentDrawMode == DrawMode.Line)
            {
                Line line = (Line)shape;
                line.X1 = startPoint.X;
                line.Y1 = startPoint.Y;
                line.X2 = endPoint.X;
                line.Y2 = endPoint.Y;
            }
            else
            {
                double left = Math.Min(startPoint.X, endPoint.X);
                double top = Math.Min(startPoint.Y, endPoint.Y);
                double width = Math.Abs(startPoint.X - endPoint.X);
                double height = Math.Abs(startPoint.Y - endPoint.Y);

                Canvas.SetLeft(shape, left);
                Canvas.SetTop(shape, top);

                if (currentDrawMode == DrawMode.Circle)
                {
                    Ellipse ellipse = (Ellipse)shape;
                    ellipse.Width = width;
                    ellipse.Height = height;
                }
                else
                {
                    shape.Width = width;
                    shape.Height = height;
                }
            }
        }
    }
}