using Microsoft.Xna.Framework;
using Microsoft.Xna.Framework.Graphics;
using RhythmBullet.Zer01HD.Utilities.UI;
using System;
using System.Collections.Generic;
using System.Linq;
using System.Text;
using System.Threading.Tasks;

namespace RhythmBullet.Zer01HD.Game.Screens.Transitions
{
    internal class FadeInTransition : IDisposable
    {
        public readonly Texture2D curtain;
        Rectangle curtainSize;
        Color color;
        private float progR, progG, progB, progA;
        private float rR, rG, rB, rA;
        private bool recorded;

        internal FadeInTransition(GraphicsDevice graphicsDevice, Color startColor, Vector2 dimensions)
        {
            curtain = new Texture2D(graphicsDevice, 1, 1);
            curtain.SetData(new[] { startColor });
            curtainSize.Width = (int)dimensions.X;
            curtainSize.Height = (int)dimensions.Y;
            color = startColor;
        }


        internal void Fade(SpriteBatch batch, float deltaf)
        {
            if (progR > 0 || progG > 0 || progB > 0)
            {
                if (!recorded)
                {
                    rR = (0 - color.R) / 1f;
                    rG = (0 - color.G) / 1f;
                    rB = (0 - color.B) / 1f;
                    rA = (0 - color.A) / 1f;
                    recorded = true;
                }

                progR += rR * deltaf;
                progR = Math.Max(progR, 0);
                progG += rG * deltaf;
                progG = Math.Max(progG, 0);
                progB += rB * deltaf;
                progB = Math.Max(progB, 0);
                progA += rA * deltaf;
                progA = Math.Max(progA, 0);
                color.R = (byte)progR;
                color.G = (byte)progG;
                color.B = (byte)progB;
                color.A = (byte)progA;
            }
            batch.Draw(curtain, curtainSize, color);
        }

        public void Dispose()
        {
            curtain.Dispose();
        }
    }
}