class Game : DynamicModule
{
    private Material2D material = Material2D.Default;
    Size size = new Size(0.02f, 0.04f);
    PhysicsBody testBody;

    public Game()
        : base("Simple Game", typeof(Application))
    {
        Settings.Debug.AllowDevelopmentAssemblyUpdating = true;
            
        if (Physics.Instance == null)
        {
            Application.Quit();
            return;
        }
        Settings.Extra.LimitFramerateNumber = 60;
        Settings.Extra.GameLogicUpdatesPerSec = 0;
        Physics.Gravity = Vector.Zero;

        testBody = Physics.CreateRectangle(0.05f, 0.05f, 1);
        testBody.Position2D = Point.Half;

        Input.Commands[Command.QuitTest].Add(delegate
        {
            Application.Quit();
        });
    }

    public override void Run()
    {
        if (Time.EverySecond)
            rows.Clear();
        DrawText("FPS: " + Time.Fps);
        DrawText("Target fps (LimitFramerateNumber): " + Settings.Extra.LimitFramerateNumber);
        DrawText("Settings.Extra.GameLogicUpdatesPerSec: " + Settings.Extra.GameLogicUpdatesPerSec);
            
        DrawText("Velocity: " + testBody.LinearVelocity.Length.ToInvariantString());
        DrawText("Press W to apply LinearImpulse or E for Force");
        DrawText("Press Mouse.LeftButton to spawn and RightButton to apply a force to them");
        DrawText("Press R to reset");
        DrawText("Press 1, 2, 3 or 4 to limit FPS to (0, 30, 60, 120)");

        HandleInput();
        foreach (PhysicsBody body in Physics.Bodies)
        {
            material.Draw(new Rectangle(body.Position2D - size / 2f, size), body.Rotation);
        }
        DrawText_D();
    }

    private void HandleInput()
    {
        if (Input.Keyboard.IsPressed(InputButton.D1))
            Settings.Extra.LimitFramerateNumber = 0;
        else if (Input.Keyboard.IsPressed(InputButton.D2))
            Settings.Extra.LimitFramerateNumber = 30;
        else if (Input.Keyboard.IsPressed(InputButton.D3))
            Settings.Extra.LimitFramerateNumber = 60;
        else if (Input.Keyboard.IsPressed(InputButton.D4))
            Settings.Extra.LimitFramerateNumber = 120;

        if (Input.Keyboard.IsPressed(InputButton.W))
        {
            testBody.ApplyLinearImpulse(Vector.UnitY * 1000000f);
        }

        if (Input.Keyboard.IsPressed(InputButton.E))
        {
            testBody.ApplyForce(Vector.UnitY * 1000000f);
        }

        if (Input.Keyboard.IsPressed(InputButton.R))
        {
            testBody.Position2D = Point.Half;
            testBody.LinearVelocity = Vector.Zero;
            testBody.Rotation = 0f;
            testBody.AngularVelocity2D = 0f;
            List<PhysicsBody> bodiesToRemove = new List<PhysicsBody>();
            foreach (PhysicsBody body in Physics.Bodies)
            {
                if (body != testBody)
                    bodiesToRemove.Add(body);
            }
            foreach (PhysicsBody body in bodiesToRemove)
            {
                body.Remove();
            }
        }

        if (Input.Mouse.LeftButtonIsPressed)
        {
            PhysicsBody body = Physics.CreateRectangle(size.Width, size.Height, 1f);
            body.Position2D = Input.Mouse.Position;
        }

        if (Input.Mouse.RightButtonIsPressed)
        {
            Physics.ApplyExplosion(new Vector(Input.Mouse.Position, 0f), 50f);
        }
    }

    List<string> rows = new List<string>();
    private void DrawText(string txt)
    {
        if (Time.EverySecond)
            rows.Add(txt);
    }

    private void DrawText_D()
    {
        float top = ScreenSpace.DrawArea.Top;
        foreach (string txt in rows)
        {
            Size s = Font.Default.Measure(txt);
            Rectangle r = new Rectangle(ScreenSpace.DrawArea.Left, top, s.Width, s.Height);
            Font.Default.Draw(txt, r);
            top += s.Height;
        }
    }
}