using Microsoft.Xna.Framework;
using Microsoft.Xna.Framework.Input;
using MrGameEng.Input;
using Xunit;

namespace MrGameEng.Input.Tests;

public class InputManagerTests
{
    private static MouseState Mouse(
        int x = 0,
        int y = 0,
        int wheel = 0,
        ButtonState left = ButtonState.Released
    ) =>
        new(
            x,
            y,
            wheel,
            left,
            ButtonState.Released,
            ButtonState.Released,
            ButtonState.Released,
            ButtonState.Released
        );

    private static void Frame(
        InputManager input,
        KeyboardState keyboard = default,
        MouseState mouse = default
    ) => input.Apply(keyboard, mouse, GamePadState.Default);

    [Fact]
    public void KeyPressed_OnlyOnTheFrameItGoesDown()
    {
        var input = new InputManager();

        Frame(input, new KeyboardState(Keys.Space));
        Assert.True(input.IsKeyPressed(Keys.Space));
        Assert.True(input.IsKeyDown(Keys.Space));

        Frame(input, new KeyboardState(Keys.Space));
        Assert.False(input.IsKeyPressed(Keys.Space));
        Assert.True(input.IsKeyDown(Keys.Space));
    }

    [Fact]
    public void KeyReleased_OnlyOnTheFrameItGoesUp()
    {
        var input = new InputManager();

        Frame(input, new KeyboardState(Keys.A));
        Frame(input);

        Assert.True(input.IsKeyReleased(Keys.A));
        Frame(input);
        Assert.False(input.IsKeyReleased(Keys.A));
    }

    [Fact]
    public void Capture_SuppressesInput_KeepsMousePositionAndWheel()
    {
        var capture = new MrGameEng.Core.InputCapture();
        var input = new InputManager(capture);

        Frame(input, new KeyboardState(Keys.W), Mouse(x: 10, y: 20, wheel: 120));
        Assert.True(input.IsKeyDown(Keys.W));

        capture.Captured = true;
        input.Update(); // ввод захвачен оверлеем — устройства не опрашиваются

        Assert.False(input.IsKeyDown(Keys.W));
        Assert.True(input.IsKeyReleased(Keys.W)); // одно корректное событие отпускания
        Assert.Equal(new Point(10, 20), input.MousePosition);
        Assert.Equal(0, input.WheelDelta);
        Assert.Equal(Point.Zero, input.MouseDelta);

        input.Update();
        Assert.False(input.IsKeyReleased(Keys.W)); // и больше никаких фантомных событий
    }

    [Fact]
    public void MouseDeltaAndWheelDelta_ComputedBetweenFrames()
    {
        var input = new InputManager();

        Frame(input, mouse: Mouse(x: 10, y: 10, wheel: 0));
        Frame(input, mouse: Mouse(x: 25, y: 5, wheel: 120));

        Assert.Equal(new Point(15, -5), input.MouseDelta);
        Assert.Equal(120, input.WheelDelta);
        Assert.Equal(new Point(25, 5), input.MousePosition);
    }

    [Fact]
    public void MousePressed_DetectsLeftButtonEdge()
    {
        var input = new InputManager();

        Frame(input, mouse: Mouse());
        Frame(input, mouse: Mouse(left: ButtonState.Pressed));

        Assert.True(input.IsMousePressed(MouseButton.Left));
        Assert.False(input.IsMousePressed(MouseButton.Right));
    }
}