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;

namespace RhythmBullet.Zer01HD.UI.Modular
{
    public class ModuleGroup : Module
    {
        List<Module> modules = new List<Module>();
        Rectangle scissorBounds;
        RasterizerState scissorRasterizer = new RasterizerState();
        public ModuleGroup(bool crop = false)
        {
            if (crop)
            {
                scissorRasterizer.ScissorTestEnable = true;
                scissorBounds = new Rectangle();
            }
        }

        public override void Draw(SpriteBatch batch)
        {
            if (scissorBounds != null)
            {
                batch.End();
                batch.Begin(SpriteSortMode.Deferred, null, null, null, scissorRasterizer);
                scissorBounds.Width = (int) Width;
                scissorBounds.Height = (int) Height;
                scissorBounds.X = (int) Position.X;
                scissorBounds.Y = (int) Position.Y;
                Rectangle scissor = scissorBounds;
                scissorBounds = batch.GraphicsDevice.ScissorRectangle;
                batch.GraphicsDevice.ScissorRectangle = scissor;
            }
            foreach (Module module in modules)
            {
                float offsetX = module.Position.X;
                float offsetY = module.Position.Y;
                module.Position.X = Position.X + offsetX;
                module.Position.Y = Position.Y + offsetY;
                module.Draw(batch);
                module.Position.X = offsetX;
                module.Position.Y = offsetY;
            }

            if (scissorBounds != null)
            {
                batch.GraphicsDevice.ScissorRectangle = scissorBounds;
                batch.End();
                batch.Begin();
            }
        }

        public override void Update(GameTime gameTime)
        {
            foreach (Module module in modules)
            {
                module.Update(gameTime);
            }
        }

        public void AddModule(params Module[] addModules)
        {
            foreach (Module module in addModules)
            {
                if (modules.Contains(module))
                {
                    throw new InvalidOperationException(module.ToString() + " already exists in " + this.ToString());
                }
                module.Parent = this;
                modules.Add(module);
            }
        }

        public void RemoveModule(Module module)
        {
            module.Parent = null;
            modules.Remove(module);
        }
    }
}