using System.Drawing;
using LeoTurtle;

namespace SimpleDrawings;

public static class TurtlePath
{
    /// <summary>
    ///     Executes the logic for adding turtle path steps.
    ///     Called automatically when the application starts.
    /// </summary>
    /// <param name="turtle">The <see cref="Turtle"/> instance to use</param>
    public static void Walk(Turtle turtle)
    {
        EulerianPath(turtle);
        Shapes(turtle);
    }

    /// <summary>
    ///     Draws a 'Haus des Nikolaus' as an Eulerian path
    /// </summary>
    /// <param name="turtle">The <see cref="Turtle"/> instance to use</param>
    private static void EulerianPath(Turtle turtle)
    {
        const double Distance = 6.0D;
        const double ShortDistance = 4.24D;
        const double LongDistance = 8.49D;

        turtle.Teleport(5, 20);
        for (int i = 0; i < 4; i++)
        {
            DrawLine(turtle, Distance, 90);
        }
        turtle.Turn(45);
        DrawLine(turtle, LongDistance, -90);
        for (int i = 0; i < 2; i++)
        {
            DrawLine(turtle, ShortDistance, -90);
        }
        DrawLine(turtle, LongDistance, 0);
        
    }

    /// <summary>
    ///     Draws several shapes.
    /// </summary>
    /// <param name="turtle">The <see cref="Turtle"/> instance to use</param>
    private static void Shapes(Turtle turtle)
    {
        DrawOctagon(turtle, 5, 5);
        DrawRhombus(turtle, 20, 5);
        DrawTriangle(turtle, 40, 5);
    }

    /// <summary>
    ///     Draws an octagon.
    /// </summary>
    /// <param name="turtle">The <see cref="Turtle"/> instance to use</param>
    /// <param name="startX">Initial turtle x position when starting to draw</param>
    /// <param name="startY">Initial turtle y position when starting to draw</param>
    private static void DrawOctagon(Turtle turtle, int startX, int startY)
    {
        const double Distance = 4.0D;
        turtle.Teleport(startX, startY);
        for (int i = 0; i < 8; i++)
        {
            DrawLine(turtle, Distance, 45);
        }
    }

    /// <summary>
    ///     Draws a rhombus.
    /// </summary>
    /// <param name="turtle">The <see cref="Turtle"/> instance to use</param>
    /// <param name="startX">Initial turtle x position when starting to draw</param>
    /// <param name="startY">Initial turtle y position when starting to draw</param>
    private static void DrawRhombus(Turtle turtle, int startX, int startY)
    {
        const double Distance = 8.0D;
        const double Angle1 = 82;
        const double Angle2 = (360 - (Angle1 * 2)) / 2;
        
        turtle.Teleport(startX + Distance / 2, startY - Distance / 2);
        turtle.Turn(-Angle1 / 2);
        for (int i = 0; i < 4; i++)
        {
            DrawLine(turtle, Distance, i % 2 == 0 ? Angle1 : Angle2);
        }
    }

    /// <summary>
    ///     Draws two triangles, one offset off the other.
    /// </summary>
    /// <param name="turtle">The <see cref="Turtle"/> instance to use</param>
    /// <param name="startX">Initial turtle x position when starting to draw</param>
    /// <param name="startY">Initial turtle y position when starting to draw</param>
    private static void DrawTriangle(Turtle turtle, int startX, int startY)
    {
        const double Offset = 1.5D;
        const double ShortSide = 6.0D;
        const double LongSide = 8.0D;
        DrawTriangle(turtle, startX, startY, LongSide, ShortSide);
        DrawTriangle(turtle, startX + Offset, startY - Offset*2, LongSide + Offset*(LongSide/2), ShortSide + Offset*(ShortSide/2));
    }

    /// <summary>
    ///     Draws a single triangle at the given position and with the given size.
    ///     Angels are fixed.
    /// </summary>
    /// <param name="turtle">The <see cref="Turtle"/> instance to use</param>
    /// <param name="startX">Initial turtle x position when starting to draw</param>
    /// <param name="startY">Initial turtle y position when starting to draw</param>
    /// <param name="longSide">Length of the side c</param>
    /// <param name="shortSide">Length of sides a & b</param>
    private static void DrawTriangle(Turtle turtle, double startX, double startY, double longSide, double shortSide)
    {
        turtle.Teleport(startX, startY);
        
        double angle = ConvertToDegrees(Math.Asin(shortSide / longSide)); // Corrected to arcsin
        DrawLine(turtle, longSide, 180 + angle); // Long side
        DrawLine(turtle, shortSide, 0);

        turtle.Teleport(startX, startY);
        turtle.Turn(-angle);
        DrawLine(turtle, shortSide, 0);
        
    }

    /// <summary>
    ///     Converts an angel from degrees to radians.
    /// </summary>
    /// <param name="angleDegrees">Degrees to convert</param>
    /// <returns>Radians value</returns>
    private static double ConvertToRadians(double angleDegrees)
    {
        return angleDegrees * Math.PI / 180;
    }

    private static double ConvertToDegrees(double angleRadians)
    {
        return angleRadians / Math.PI * 180;
    }

    private static void DrawLine(Turtle turtle, double distance, double rotation)
    {
        turtle.MoveForward(distance);
        turtle.Turn(rotation);
    }
}