using Microsoft.Xna.Framework;
using Microsoft.Xna.Framework.Graphics;
using TrueCraft.Client.Rendering;
using TrueCraft.Core.Logic.Items;
using TrueCraft.API.Logic;

namespace TrueCraft.Client.Modules
{
    public class HUDModule : IGraphicalModule
    {
        private TrueCraftGame Game { get; set; }
        private SpriteBatch SpriteBatch { get; set; }
        private Texture2D GUI { get; set; }
        private Texture2D Icons { get; set; }
        private Texture2D Items { get; set; }
        private FontRenderer Font { get; set; }

        public HUDModule(TrueCraftGame game, FontRenderer font)
        {
            Game = game;
            Font = font;
            SpriteBatch = new SpriteBatch(game.GraphicsDevice);
            GUI = game.TextureMapper.GetTexture("gui/gui.png");
            Icons = game.TextureMapper.GetTexture("gui/icons.png");
            Items = game.TextureMapper.GetTexture("gui/items.png");
        }

        public void Update(GameTime gameTime)
        {
        }

        static readonly Color CrosshairColor = new Color(255, 255, 255, 70);

        public void Draw(GameTime gameTime)
        {
            SpriteBatch.Begin(samplerState: SamplerState.PointClamp, blendState: BlendState.NonPremultiplied);
            
            SpriteBatch.Draw(Icons, new Vector2(
                Game.GraphicsDevice.Viewport.Width / 2 - (8 * Game.ScaleFactor * 2),
                Game.GraphicsDevice.Viewport.Height / 2 - (8 * Game.ScaleFactor * 2)),
                new Rectangle(0, 0, 16, 16), CrosshairColor,
                0, Vector2.Zero, Game.ScaleFactor * 2, SpriteEffects.None, 1);

            DrawHotbar(gameTime);
            DrawHotbarItemSprites(gameTime);

            SpriteBatch.End();

            DrawHotbarBlockSprites(gameTime);

            // Once more, with feeling
            SpriteBatch.Begin(samplerState: SamplerState.PointClamp, blendState: BlendState.NonPremultiplied);
            DrawHotbarSlotCounts(gameTime);
            SpriteBatch.End();
        }

        #region "Hotbar"

        /// <summary>
        /// The dimensions of the hotbar background.
        /// </summary>
        private static readonly Rectangle HotbarBackgroundRect =
            new Rectangle(0, 0, 182, 22);

        /// <summary>
        /// The dimensions of the hotbar selection.
        /// </summary>
        private static readonly Rectangle HotbarSelectionRect =
            new Rectangle(0, 22, 24, 24);

        /// <summary>
        /// Draws the inventory hotbar.
        /// </summary>
        /// <param name="gameTime"></param>
        private void DrawHotbar(GameTime gameTime)
        {
            // Background
            SpriteBatch.Draw(GUI, new Vector2(
                Game.GraphicsDevice.Viewport.Width / 2 - Scale(HotbarBackgroundRect.Width / 2),
                Game.GraphicsDevice.Viewport.Height - Scale(HotbarBackgroundRect.Height + 5)),
                HotbarBackgroundRect, Color.White, 0, Vector2.Zero, Game.ScaleFactor * 2, SpriteEffects.None, 1);

            // TODO: Icons

            // Selection
            SpriteBatch.Draw(GUI, new Vector2(
                Game.GraphicsDevice.Viewport.Width / 2 - Scale(HotbarBackgroundRect.Width / 2) + Scale(Game.Client.HotbarSelection * 20 - 1),
                Game.GraphicsDevice.Viewport.Height - Scale(HotbarBackgroundRect.Height + 6)),
                HotbarSelectionRect, Color.White, 0, Vector2.Zero, Game.ScaleFactor * 2, SpriteEffects.None, 1);
        }

        private void DrawHotbarItemSprites(GameTime gameTime)
        {
            var scale = new Point((int)(16 * Game.ScaleFactor * 2));
            var origin = new Point((int)(Game.GraphicsDevice.Viewport.Width / 2 - Scale(HotbarBackgroundRect.Width / 2)),
                    (int)(Game.GraphicsDevice.Viewport.Height - Scale(HotbarBackgroundRect.Height + 5)));
            origin.X += (int)Scale(3);
            origin.Y += (int)Scale(3);
            for (int i = 0; i < Game.Client.Inventory.Hotbar.Length; i++)
            {
                var item = Game.Client.Inventory.Hotbar[i];
                if (item.Empty)
                    continue;
                var provider = Game.ItemRepository.GetItemProvider(item.ID);
                if (provider.GetIconTexture((byte)item.Metadata) == null)
                    continue;
                var position = origin + new Point((int)Scale(i * 20), 0);
                var rect = new Rectangle(position, scale);
                IconRenderer.RenderItemIcon(SpriteBatch, Items, provider,
                    (byte)item.Metadata, rect, Color.White); // TODO: Fuck, metadata was supposed to be a short
            }
        }

        private void DrawHotbarBlockSprites(GameTime gameTime)
        {
            var scale = new Point((int)(16 * Game.ScaleFactor * 2));
            var origin = new Point((int)(Game.GraphicsDevice.Viewport.Width / 2 - Scale(HotbarBackgroundRect.Width / 2)),
                    (int)(Game.GraphicsDevice.Viewport.Height - Scale(HotbarBackgroundRect.Height + 5)));
            origin.X += (int)Scale(3);
            origin.Y += (int)Scale(3);
            for (int i = 0; i < Game.Client.Inventory.Hotbar.Length; i++)
            {
                var item = Game.Client.Inventory.Hotbar[i];
                if (item.Empty)
                    continue;
                var provider = Game.ItemRepository.GetItemProvider(item.ID) as IBlockProvider;
                if (provider == null || provider.GetIconTexture((byte)item.Metadata) != null)
                    continue;
                var position = origin + new Point((int)Scale(i * 20), 0);
                var rect = new Rectangle(position, scale);
                IconRenderer.RenderBlockIcon(Game, Items, provider,
                    (byte)item.Metadata, rect, Color.White); // TODO: Fuck, metadata was supposed to be a short
            }
        }

        private void DrawHotbarSlotCounts(GameTime gameTime)
        {
            var origin = new Point((int)(Game.GraphicsDevice.Viewport.Width / 2 - Scale(HotbarBackgroundRect.Width / 2)),
                    (int)(Game.GraphicsDevice.Viewport.Height - Scale(HotbarBackgroundRect.Height + 5)));
            origin.X += (int)Scale(3);
            origin.Y += (int)Scale(3);
            for (int i = 0; i < Game.Client.Inventory.Hotbar.Length; i++)
            {
                var item = Game.Client.Inventory.Hotbar[i];
                if (item.Empty || item.Count == 1)
                    continue;
                int offset = 12;
                if (item.Count >= 10)
                    offset -= 6;
                var position = origin + new Point((int)Scale(i * 20 + offset), (int)Scale(5));
                Font.DrawText(SpriteBatch, position.X, position.Y, item.Count.ToString(), Game.ScaleFactor);
            }
        }

        #endregion

        /// <summary>
        /// Scales a float depending on the game's scale factor.
        /// </summary>
        /// <param name="value"></param>
        /// <returns></returns>
        private float Scale(float value)
        {
            return value * Game.ScaleFactor * 2;
        }
    }
}