using Microsoft.Xna.Framework;
using Microsoft.Xna.Framework.Graphics;
using static CorinnaMod.LogicUtilities;
using static CorinnaMod.Graphics.Spritesheets.UI.UISpriteIDs;
using static CorinnaMod.EntityData.PlayerData.PlayerInfo;

namespace CorinnaMod.UI.UIData
{
    /// <summary>
    /// Handles the logic and drawing of the item slots in the player ui.
    /// </summary>
    public class PlayerHotBar
    {
        /// <summary>
        /// Amount of item background inventory slots to be drawn.
        /// </summary>
        private static int AmountofItemSlots
            => 10;

        /// <summary>
        /// Horizontal offset to begin drawing the hotbar squares.
        /// </summary>
        private static int HotBarXOffset
            => (int)(0.1f * ScreenW);

        /// <summary>
        /// Vertical offset to begin drawing the hotbar Squares.
        /// </summary>
        private static float HotBarYOffSet
            => 0.8f * ScreenH;

        /// <summary>
        /// Coordinates of the left-top point of the hotbar.
        /// </summary>
        public static Vector2 HotBarPosition
            => new Vector2(HotBarXOffset, HotBarYOffSet);

        /// <summary>
        /// Space between the hotbar slots.
        /// </summary>
        private static int HotBarMargin
            => 6;

        /// <summary>
        /// Draws a background item slot graphic, then draws the inventory item related to that particular slot
        /// over it.
        /// </summary>
        /// <param name="spriteBatch">More like sprite bitch.</param>
        public static void DrawHotBar(SpriteBatch spriteBatch)
        {
            for (int Index = 0; Index < AmountofItemSlots; Index++)
            {
                DrawItemSlot(spriteBatch, Index);
                DrawItemOverSlot(spriteBatch, Index);
            }

        }

        /// <summary>
        /// Sets the cooordinates of each slot.
        /// </summary>
        /// <param name="Index">Iteration of the hotbar.</param>
        /// <returns></returns>
        public static Vector2 CalculateHotBarPosition(int Index)
            => new Vector2(((Index * HotBarMargin) + (Index * ItemSlot.Width)) + HotBarXOffset, HotBarYOffSet);

        /// <summary>
        /// Where to draw the item graphic and accounts for scaling to have it centered.
        /// </summary>
        /// <param name="Index">Iteration of the hotbar slot.</param>
        /// <param name="HotBarPosition">Top left coordinates of the current iteration of the hotbarslot./param>
        /// <returns></returns>
        public static Vector2 CalculateItemPosition(int Index, Vector2 HotBarPosition)
            => ScaleTexture(GetInventoryItemSlotTexture(Index)) == 0.5f ?
               HotBarPosition.AddXY(CenterMargins(ItemSlot.Width, GetInventoryItemSlotTexture(Index).Width * 0.5f),
                                    CenterMargins(ItemSlot.Height, GetInventoryItemSlotTexture(Index).Height * 0.5f)):
               HotBarPosition.AddXY(CenterMargins(ItemSlot.Width, GetInventoryItemSlotTexture(Index).Width),
                                    CenterMargins(ItemSlot.Height, GetInventoryItemSlotTexture(Index).Height));

        /// <summary>
        /// Scales down textures if they're too big to fit in the hotbar background icon.
        /// </summary>
        /// <param name="Texture">The texture.</param>
        /// <returns>A float to scale down the texture if needed.</returns>
        public static float ScaleTexture(Texture2D Texture)
            => Texture.Width < ItemSlot.Width && Texture.Height < ItemSlot.Height ? 1 : 0.5f;

        /// <summary>
        /// Calls the spritebatch to draw the background graphic of the item slot.
        /// </summary>
        /// <param name="Batch">The spritebatch object.</param>
        /// <param name="Index">The current iteration of the hotbar slot.</param>
        private static void DrawItemSlot(SpriteBatch Batch, int Index)
            => Batch.Draw(ItemSlot, CalculateHotBarPosition(Index), Color.White);

        /// <summary>
        /// Draws the item after the background slot has been drawn.
        /// </summary>
        /// <param name="Batch">The spritebatch object.</param>
        /// <param name="Index">The current iteration of the hotbar slot.</param>
        private static void DrawItemOverSlot(SpriteBatch Batch, int Index)
            => Batch.DrawtoScale(GetInventoryItemSlotTexture(Index),
                                 CalculateItemPosition(Index, CalculateHotBarPosition(Index)),
                                 ScaleTexture(GetInventoryItemSlotTexture(Index)));
    }
}