using Microsoft.Xna.Framework;
using Microsoft.Xna.Framework.Graphics;
using Microsoft.Xna.Framework.Input;
using RecrownedAthenaeum.Input;
using RecrownedAthenaeum.Render;
using System;

namespace RecrownedAthenaeum.UI.Modular
{

    /// <summary>
    /// Module for UI layout.
    /// </summary>
    public class UIModule : IInputListener
    {
        private RectangleRenderer rectangleRenderer;

        /// <summary>
        /// Draws rectangle using the bounds of this module.
        /// </summary>
        public bool Debugging { set { if (value) { if (rectangleRenderer == null) rectangleRenderer = new RectangleRenderer(); } else { rectangleRenderer?.Dispose(); rectangleRenderer = null; } } get { return rectangleRenderer != null; } }

        /// <summary>
        /// The bounds before factoring in the origin.
        /// </summary>
        public Rectangle bounds;

        /// <summary>
        /// Bounds of this module (after factoring in the origin).
        /// </summary>
        public Rectangle ActualBounds
        {
            get
            {
                return new Rectangle((int)(bounds.X - origin.X), (int)(bounds.Y - origin.Y), bounds.Width, bounds.Height);
            }
        }

        /// <summary>
        /// Origin of this module.
        /// </summary>
        public Vector2 origin;
        
        /// <summary>
        /// The parent of this module. May be null.
        /// </summary>
        public UIModuleGroup Parent;

        /// <summary>
        /// Name of this module. For organizational/referencial purposes mostly.
        /// </summary>
        public string Name;

        /// <summary>
        /// The color tint of this module.
        /// </summary>
        public Color color = Color.White;

        /// <summary>
        /// Called every frame to update this module. Calculations and movement should go here.
        /// </summary>
        /// <param name="gameTime">Game time information.</param>
        public virtual void Update(GameTime gameTime)
        {

        }

        /// <summary>
        /// Called every frame to draw this module. Anything that needs to be drawn should go here.
        /// </summary>
        /// <param name="batch">Batch used to draw.</param>
        public virtual void Draw(SpriteBatch batch)
        {
            if (Debugging)
            {
                rectangleRenderer.Begin();
                rectangleRenderer.Draw(ActualBounds.X, ActualBounds.Y, ActualBounds.Width, ActualBounds.Height, Color.Red);
                rectangleRenderer.End();
            }
        }

        /// <summary>
        /// Converts the given rectangle to the coordinates of the parent.
        /// </summary>
        /// <param name="rectangle">Rectangle to convert.</param>
        /// <returns></returns>
        public Rectangle ConvertToParentCoordinates(Rectangle rectangle)
        {
            if (Parent != null)
            {
                Rectangle parentHitbox = Parent.ConvertToParentCoordinates(rectangle);
                int tX = rectangle.X + parentHitbox.X;
                int tY = rectangle.Y + parentHitbox.Y;
                return new Rectangle(tX, tY, rectangle.Width, rectangle.Height);
            } else
            {
                return rectangle;
            }
        }

        /// <summary>
        /// Removes this module from the parent.
        /// </summary>
        public void RemoveFromParent()
        {
            if (Parent == null) throw new InvalidOperationException("Parent is null.");
            Parent.RemoveModule(this);
        }

        /// <summary>
        /// Called whenever the keyboard state is changed.
        /// </summary>
        /// <param name="state">The current keyboard state.</param>
        /// <returns>Returning whether or not to continue to call the next listener.</returns>
        public virtual bool KeyboardStateChanged(KeyboardState state)
        {
            return true;
        }

        /// <summary>
        /// Called whenever the state of the mouse changes. This includes movement.
        /// </summary>
        /// <param name="state">The current state of the mouse.</param>
        /// <returns>Returning whether or not to continue to call the next listener.</returns>
        public virtual bool MouseStateChanged(MouseState state)
        {
            return true;
        }

        /// <summary>
        /// Sets the origin to be the center of the bounds.
        /// </summary>
        public void CenterOrigin()
        {
            origin.X = bounds.Width / 2f;
            origin.Y = bounds.Height / 2f;
        }
    }
}