using Microsoft.Xna.Framework;
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
    {
        /// <summary>
        /// The bounds before factoring in the origin.
        /// </summary>
        public Rectangle situation;

        /// <summary>
        /// Bounds of this module (after factoring in the origin).
        /// </summary>
        public Rectangle Boundaries
        {
            get
            {
                return new Rectangle((int)(situation.X - origin.X), (int)(situation.Y - origin.Y), situation.Width, situation.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(ConsistentSpriteBatch batch)
        {
        }

        /// <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 = situation.Width / 2f;
            origin.Y = situation.Height / 2f;
        }

        /// <summary>
        /// Centers this module's origin on the horizontal axis relative to the parent <see cref="UIModuleGroup"/>.
        /// </summary>
        /// <returns>True if possible and false if not.</returns>
        public bool CenterHorizontally()
        {
            if (parent != null)
            {
                Rectangle rectangle = parent.Boundaries;
                if (parent != null && rectangle.Width >= Boundaries.Width)
                {
                    situation.X = rectangle.Width / 2 + situation.X;
                    return true;
                }
            }
            return false;
        }

        /// <summary>
        /// Centers this module's origin on the vertical axis relative to the parent <see cref="UIModuleGroup"/>.
        /// </summary>
        /// <returns>True if possible.</returns>
        public bool CenterVertically()
        {
            if (parent != null)
            {
                Rectangle rectangle = parent.Boundaries;
                if (rectangle.Height >= Boundaries.Height)
                {
                    situation.Y = rectangle.Height / 2 + situation.Y;
                    return true;
                }
            }
            return false;
        }
    }
}