using System;
using System.Collections.Generic;
using System.Linq;
using System.Text;
using System.Threading.Tasks;
using Microsoft.Xna.Framework;
using Microsoft.Xna.Framework.Graphics;
using Microsoft.Xna.Framework.Input;

namespace Tutorial030.Controls
{
  public class Button : Component
  {
    protected MouseState _previousMouse;

    protected MouseState _currentMouse;

    protected Texture2D _texture;

    protected SpriteFont _font;

    protected Color _colour;

    public Vector2 Position;

    public Rectangle Rectangle
    {
      get
      {
        return new Rectangle((int)Position.X, (int)Position.Y, _texture.Width, _texture.Height);
      }
    }

    public Color PenColour { get; set; }

    public string Text { get; set; }

    public bool IsHovering { get; set; }

    public Action OnClick { get; set; }

    public Button(Texture2D texture)
      : this(texture, null)
    {

    }

    public Button(Texture2D texture, SpriteFont font)
    {
      _texture = texture;

      _font = font;

      Text = "";

      PenColour = Color.White;
    }

    public override void Update(GameTime gameTime)
    {
      _previousMouse = _currentMouse;
      _currentMouse = Mouse.GetState();

      var mouseRectangle = new Rectangle(_currentMouse.X, _currentMouse.Y, 1, 1);

      IsHovering = false;
      _colour = Color.White;

      if (mouseRectangle.Intersects(Rectangle))
      {
        IsHovering = true;
        _colour = Color.Yellow;

        if (_previousMouse.LeftButton == ButtonState.Pressed && _currentMouse.LeftButton == ButtonState.Released)
        {
          OnClick?.Invoke();
        }
      }
    }

    public override void Draw(GameTime gameTime, SpriteBatch spriteBatch)
    {
      spriteBatch.Draw(_texture, Position, _colour);

      if (_font != null)
      {
        var x = (Rectangle.X + (Rectangle.Width / 2)) - (_font.MeasureString(Text).X / 2);
        var y = (Rectangle.Y + (Rectangle.Height / 2)) - (_font.MeasureString(Text).Y / 2);

        spriteBatch.DrawString(_font, Text, new Vector2(x, y), PenColour);
      }
    }
  }
}