using System;
using System.Collections.Generic;
using System.Drawing;
using System.Drawing.Imaging;
using System.Linq;
using System.Runtime.InteropServices;
using System.Text;
using System.Threading.Tasks;

namespace Tango.RemoteDesktop.Utils
{
    /// <summary>
    /// Represents a bitmap object with fast Get/Set Pixel methods.
    /// </summary>
    /// <seealso cref="System.IDisposable" />
    public class DirectBitmap : IDisposable
    {
        public Bitmap Bitmap { get; private set; }
        public Int32[] Bits { get; private set; }
        public bool Disposed { get; private set; }
        public int Height { get; private set; }
        public int Width { get; private set; }

        protected GCHandle BitsHandle { get; private set; }

        /// <summary>
        /// Initializes a new instance of the <see cref="DirectBitmap"/> class.
        /// </summary>
        /// <param name="width">The width.</param>
        /// <param name="height">The height.</param>
        public DirectBitmap(int width, int height)
        {
            Width = width;
            Height = height;
            Bits = new Int32[width * height];
            BitsHandle = GCHandle.Alloc(Bits, GCHandleType.Pinned);
            Bitmap = new Bitmap(width, height, width * 4, PixelFormat.Format32bppPArgb, BitsHandle.AddrOfPinnedObject());
        }

        /// <summary>
        /// Sets the pixel color.
        /// </summary>
        /// <param name="x">The x position.</param>
        /// <param name="y">The y position.</param>
        /// <param name="color">The color.</param>
        public void SetPixel(int x, int y, Color color)
        {
            int index = x + (y * Width);
            int col = color.ToArgb();

            Bits[index] = col;
        }

        /// <summary>
        /// Gets the pixel color.
        /// </summary>
        /// <param name="x">The x position.</param>
        /// <param name="y">The y position.</param>
        /// <returns></returns>
        public Color GetPixel(int x, int y)
        {
            int index = x + (y * Width);
            int col = Bits[index];
            Color result = Color.FromArgb(col);

            return result;
        }

        /// <summary>
        /// Releases unmanaged and - optionally - managed resources.
        /// </summary>
        public void Dispose()
        {
            if (Disposed) return;
            Disposed = true;
            BitsHandle.Free();
        }
    }
}