using System;
using System.Linq;
using System.Collections.Generic;
using System.Drawing;
using System.Text;
using System.Runtime.InteropServices;
using System.Windows.Forms;

namespace INT69DB_2A
{
    public static class IntechGraphics
    {
        public enum TernaryRasterOperations : uint
        {
            /// <summary>dest = source</summary>
            SRCCOPY = 0x00CC0020,
            /// <summary>dest = source OR dest</summary>
            SRCPAINT = 0x00EE0086,
            /// <summary>dest = source AND dest</summary>
            SRCAND = 0x008800C6,
            /// <summary>dest = source XOR dest</summary>
            SRCINVERT = 0x00660046,
            /// <summary>dest = source AND (NOT dest)</summary>
            SRCERASE = 0x00440328,
            /// <summary>dest = (NOT source)</summary>
            NOTSRCCOPY = 0x00330008,
            /// <summary>dest = (NOT src) AND (NOT dest)</summary>
            NOTSRCERASE = 0x001100A6,
            /// <summary>dest = (source AND pattern)</summary>
            MERGECOPY = 0x00C000CA,
            /// <summary>dest = (NOT source) OR dest</summary>
            MERGEPAINT = 0x00BB0226,
            /// <summary>dest = pattern</summary>
            PATCOPY = 0x00F00021,
            /// <summary>dest = DPSnoo</summary>
            PATPAINT = 0x00FB0A09,
            /// <summary>dest = pattern XOR dest</summary>
            PATINVERT = 0x005A0049,
            /// <summary>dest = (NOT dest)</summary>
            DSTINVERT = 0x00550009,
            /// <summary>dest = BLACK</summary>
            BLACKNESS = 0x00000042,
            /// <summary>dest = WHITE</summary>
            WHITENESS = 0x00FF0062
        }

        [DllImport("Coredll.dll")]
        private static extern IntPtr GetDC(IntPtr hWnd);
        [DllImport("Coredll.dll")]
        private static extern IntPtr CreateCompatibleDC(IntPtr hdc);
        [DllImport("coredll.dll")]
        private static extern IntPtr CreateCompatibleBitmap(IntPtr hdc, int nWidth, int nHeight);
        [DllImport("coredll.dll")]
        private static extern IntPtr SelectObject(IntPtr hDC, IntPtr hObject);
        [DllImport("coredll.dll")]
        private static extern int BitBlt(IntPtr hdcDest, int nXDest, int nYDest, int nWidth, int nHeight, IntPtr hdcSrc, int nXSrc, int nYSrc, uint dwRop);
        [DllImport("coredll.dll")]
        private static extern int DeleteDC(IntPtr hdc);
        [DllImport("coredll.dll")]
        private static extern IntPtr ReleaseDC(IntPtr hWnd, IntPtr hDC);
        [DllImport("coredll.dll")]
        private static extern IntPtr DeleteObject(IntPtr hObject);

        public static Bitmap CopyFromScreen()
        {
            int width = Screen.PrimaryScreen.Bounds.Width;
            int height = Screen.PrimaryScreen.Bounds.Height;

            IntPtr hBitmap;
            IntPtr hDC = GetDC(IntPtr.Zero);
            IntPtr hMemDC = CreateCompatibleDC(hDC);

            hBitmap = CreateCompatibleBitmap(hDC, width, height);

            if (hBitmap != IntPtr.Zero)
            {
                IntPtr hOld = (IntPtr)SelectObject(hMemDC, hBitmap);
                BitBlt(hMemDC, 0, 0, width, height, hDC, 0, 0, (uint)TernaryRasterOperations.SRCCOPY);
                SelectObject(hMemDC, hOld);

                DeleteDC(hMemDC);
                ReleaseDC(IntPtr.Zero, hDC);

                Bitmap bmp = System.Drawing.Image.FromHbitmap(hBitmap);
                DeleteObject(hBitmap);

                return bmp;
            }

            return null;
        }
    }
}