using System;
using System.Collections.Generic;
using System.Linq;
using System.Text;
using System.Drawing;
using System.IO;

namespace AnimationTime
{
    class AnimatedPicture : IDisposable
    {
        public Image ImageToAnimate;
        public Rectangle CurrentCell;
        public Rectangle SizeRect;
        public int CellSize;

        private int CurrentFrame;
        private int TotalFrames;
        private MemoryStream FileData;

        public int Top
        {
            set
            {
                SizeRect.Y = value;
            }
        }

        public int Left
        {
            set
            {
                SizeRect.X = value;
            }
        }

        public AnimatedPicture(string ImageFile)
        {
            using (FileStream Read = new FileStream(ImageFile, FileMode.Open, FileAccess.Read, FileShare.Read))
            {
                // Read the source file into a byte array.
                byte[] bytes = new byte[Read.Length];
                int numBytesToRead = (int)Read.Length;
                int numBytesRead = 0;
                while (numBytesToRead > 0)
                {
                    // Read may return anything from 0 to numBytesToRead.
                    int n = Read.Read(bytes, numBytesRead, numBytesToRead);

                    // Break when the end of the file is reached.
                    if (n == 0)
                        break;

                    numBytesRead += n;
                    numBytesToRead -= n;
                }

                // Wrap the byte array in a memory stream, so the image class can load it.
                FileData = new MemoryStream(bytes);

                // Close the file, so editing programs can save to it.
                Read.Close();
            }

            ImageToAnimate = Image.FromStream(FileData);
            CellSize = ImageToAnimate.Height;
            CurrentCell = new Rectangle(0, 0, CellSize, CellSize);
            SizeRect = new Rectangle(0, 0, CellSize, CellSize);

            CurrentFrame = 0;
            TotalFrames = ImageToAnimate.Width / CellSize;

        }
        
        public void Update()
        {
            // Prepare for the next render
            CurrentFrame++;
            if (CurrentFrame >= TotalFrames)
                CurrentFrame = 0;

            CurrentCell.X = CurrentFrame * CellSize;
        }

        public void Dispose()
        {
            // Call dispose on resources we are done with.
            ImageToAnimate.Dispose();
            FileData.Dispose();
        }
    }
}