// Copyright (c) Microsoft Corporation
// The Microsoft Corporation licenses this file to you under the MIT license.
// See the LICENSE file in the project root for more information.

using System;
using System.Runtime.InteropServices;

namespace PreviewHandlerCommon.ComInterop
{
    /// <summary>
    /// Interop methods
    /// </summary>
    internal class NativeMethods
    {
        /// <summary>
        /// Changes the parent window of the specified child window.
        /// </summary>
        /// <param name="hWndChild">A handle to the child window.</param>
        /// <param name="hWndNewParent">A handle to the new parent window.</param>
        /// <returns>If the function succeeds, the return value is a handle to the previous parent window and NULL in case of failure.</returns>
        [DllImport("user32.dll")]
        public static extern IntPtr SetParent(IntPtr hWndChild, IntPtr hWndNewParent);

        /// <summary>
        /// Retrieves the handle to the window that has the keyboard focus, if the window is attached to the calling thread's message queue.
        /// </summary>
        /// <returns>The return value is the handle to the window with the keyboard focus. If the calling thread's message queue does not have an associated window with the keyboard focus, the return value is NULL.</returns>
        [DllImport("user32.dll", CharSet = CharSet.Auto)]
        public static extern IntPtr GetFocus();

        [DllImport("user32.dll", SetLastError = true)]
        public static extern int GetWindowLong(IntPtr hWnd, int nIndex);

        [DllImport("user32.dll", SetLastError = true)]
        public static extern int SetWindowLong(IntPtr hWnd, int nIndex, int dwNewLong);
    }
}
