using System;
using System.Drawing;
using System.Runtime.InteropServices;
using TaskbarLib.Interop;

namespace TaskbarLib.DesktopIntegration
{
    /// <summary>
    /// The primary coordinator of the Windows 7 taskbar-related activities.
    /// For additional functionality, see the JumpListManager
    /// and ThumbButtonManager classes.
    /// </summary>
    public static class Windows7Taskbar
    {
        #region Infrastructure

        /// <summary>
        /// The WM_TaskbarButtonCreated message number.
        /// </summary>
        public static uint TaskbarButtonCreatedMessage
        {
            get { return UnsafeNativeMethods.WM_TaskbarButtonCreated; }
        }

        // Use thread static to work around COM threading issues.
        [ThreadStatic]
        private static ITaskbarList3 _taskbarList;
        internal static ITaskbarList3 TaskbarList
        {
            get
            {
                if (_taskbarList == null)
                {
                    _taskbarList = (ITaskbarList3)new CTaskbarList();
                    _taskbarList.HrInit();
                }
                return _taskbarList;
            }
        }

        private static IPropertyStore InternalGetWindowPropertyStore(IntPtr hwnd)
        {
            IPropertyStore propStore;
            int rc = UnsafeNativeMethods.SHGetPropertyStoreForWindow(hwnd, ref SafeNativeMethods.IID_IPropertyStore, out propStore);
            if (rc != 0)
                throw Marshal.GetExceptionForHR(rc);

            return propStore;
        }

        private static void InternalEnableCustomWindowPreview(IntPtr hwnd, bool enable)
        {
            int t = enable ? 1 : 0;

            int rc;
            rc = UnsafeNativeMethods.DwmSetWindowAttribute(hwnd, SafeNativeMethods.DWMWA_HAS_ICONIC_BITMAP, ref t, 4);
            if (rc != 0)
                throw Marshal.GetExceptionForHR(rc);

            rc = UnsafeNativeMethods.DwmSetWindowAttribute(hwnd, SafeNativeMethods.DWMWA_FORCE_ICONIC_REPRESENTATION, ref t, 4);
            if (rc != 0)
                throw Marshal.GetExceptionForHR(rc);
        }

        #endregion

        #region Application Id

        /// <summary>
        /// Gets a window's application id by its window handle.
        /// </summary>
        /// <param name="hwnd">The window handle.</param>
        /// <returns>The application id of that window.</returns>
        public static string GetWindowAppId(IntPtr hwnd)
        {
            IPropertyStore propStore = InternalGetWindowPropertyStore(hwnd);

            PropVariant pv;
            propStore.GetValue(ref PropertyKey.PKEY_AppUserModel_ID, out pv);

            Marshal.ReleaseComObject(propStore);

            return pv.GetValue(); 
        }

        /// <summary>
        /// Sets the window's application id by its window handle.
        /// </summary>
        /// <param name="hwnd">The window handle.</param>
        /// <param name="appId">The application id.</param>
        public static void SetWindowAppId(IntPtr hwnd, string appId)
        {
            IPropertyStore propStore = InternalGetWindowPropertyStore(hwnd);

            PropVariant pv = new PropVariant();
            pv.SetValue(appId);
            propStore.SetValue(ref PropertyKey.PKEY_AppUserModel_ID, ref pv);

            Marshal.ReleaseComObject(propStore);
        }

        /// <summary>
        /// Sets the current process' explicit application user model id.
        /// </summary>
        /// <param name="appId">The application id.</param>
        public static void SetCurrentProcessAppId(string appId)
        {
            UnsafeNativeMethods.SetCurrentProcessExplicitAppUserModelID(appId);
        }

        /// <summary>
        /// Gets the current process' explicit application user model id.
        /// </summary>
        /// <returns>The application id.</returns>
        public static string GetCurrentProcessAppId()
        {
            string appId;
            UnsafeNativeMethods.GetCurrentProcessExplicitAppUserModelID(out appId);
            return appId;
        }

        #endregion

        #region DWM Iconic Thumbnail and Peek Bitmap

        /// <summary>
        /// Indicates that the specified window requests the DWM
        /// to demand live preview (thumbnail and peek) mode when necessary
        /// instead of relying on default preview.
        /// </summary>
        /// <param name="hwnd">The window handle.</param>
        public static void EnableCustomWindowPreview(IntPtr hwnd)
        {
            InternalEnableCustomWindowPreview(hwnd, true);
        }

        /// <summary>
        /// Indicates that the specified window does not require the DWM
        /// to demand live preview (thumbnail and peek) mode when necessary,
        /// i.e. this window relies on default preview.
        /// </summary>
        /// <param name="hwnd">The window handle.</param>
        public static void DisableCustomWindowPreview(IntPtr hwnd)
        {
            InternalEnableCustomWindowPreview(hwnd, false);
        }

        /// <summary>
        /// Sets the specified iconic thumbnail for the specified window.
        /// This is typically done in response to a DWM message.
        /// </summary>
        /// <param name="hwnd">The window handle.</param>
        /// <param name="bitmap">The thumbnail bitmap.</param>
        public static void SetIconicThumbnail(IntPtr hwnd, Bitmap bitmap)
        {
            int rc = UnsafeNativeMethods.DwmSetIconicThumbnail(hwnd, bitmap.GetHbitmap(), SafeNativeMethods.DWM_SIT_DISPLAYFRAME);
            if (rc != 0)
                throw Marshal.GetExceptionForHR(rc);
        }

        /// <summary>
        /// Sets the specified peek (live preview) bitmap for the specified
        /// window.  This is typically done in response to a DWM message.
        /// </summary>
        /// <param name="hwnd">The window handle.</param>
        /// <param name="bitmap">The thumbnail bitmap.</param>
        /// <param name="displayFrame">Whether to display a standard window
        /// frame around the bitmap.</param>
        public static void SetPeekBitmap(IntPtr hwnd, Bitmap bitmap, bool displayFrame)
        {
            int rc = UnsafeNativeMethods.DwmSetIconicLivePreviewBitmap(hwnd, bitmap.GetHbitmap(), IntPtr.Zero, displayFrame ? SafeNativeMethods.DWM_SIT_DISPLAYFRAME : (uint)0);
            
            if (rc != 0)
                throw Marshal.GetExceptionForHR(rc);
        }
      
        /// <summary>
        /// Sets the specified peek (live preview) bitmap for the specified
        /// window.  This is typically done in response to a DWM message.
        /// </summary>
        /// <param name="hwnd">The window handle.</param>
        /// <param name="bitmap">The thumbnail bitmap.</param>
        /// <param name="offset">The client area offset at which to display
        /// the specified bitmap.  The rest of the parent window will be
        /// displayed as "remembered" by the DWM.</param>
        /// <param name="displayFrame">Whether to display a standard window
        /// frame around the bitmap.</param>
        public static void SetPeekBitmap(IntPtr hwnd, Bitmap bitmap, Point offset, bool displayFrame)
        {
            var nativePoint = new POINT(offset.X, offset.Y);
            int rc = UnsafeNativeMethods.DwmSetIconicLivePreviewBitmap(hwnd, bitmap.GetHbitmap(), ref nativePoint, displayFrame ? SafeNativeMethods.DWM_SIT_DISPLAYFRAME : (uint)0);
            if (rc != 0)
                throw Marshal.GetExceptionForHR(rc);
        }

        #endregion

        #region Taskbar Overlay Icon

        /// <summary>
        /// Draws the specified overlay icon on the specified window's
        /// taskbar button.
        /// </summary>
        /// <param name="hwnd">The window handle.</param>
        /// <param name="icon">The overlay icon.</param>
        /// <param name="description">The overlay icon description.</param>
        public static void SetTaskbarOverlayIcon(IntPtr hwnd, Icon icon, string description)
        {
            TaskbarList.SetOverlayIcon(
                hwnd,
                icon == null ? IntPtr.Zero : icon.Handle,
                description);
        }

        #endregion

        #region Taskbar Progress Bar

        /// <summary>
        /// Represents the thumbnail progress bar state.
        /// </summary>
        public enum ThumbnailProgressState
        {
            /// <summary>
            /// No progress is displayed.
            /// </summary>
            NoProgress = 0,
            /// <summary>
            /// The progress is indeterminate (marquee).
            /// </summary>
            Indeterminate = 0x1,
            /// <summary>
            /// Normal progress is displayed.
            /// </summary>
            Normal = 0x2,
            /// <summary>
            /// An error occurred (red).
            /// </summary>
            Error = 0x4,
            /// <summary>
            /// The operation is paused (yellow).
            /// </summary>
            Paused = 0x8
        }

        /// <summary>
        /// Sets the progress state of the specified window's
        /// taskbar button.
        /// </summary>
        /// <param name="hwnd">The window handle.</param>
        /// <param name="state">The progress state.</param>
        public static void SetProgressState(IntPtr hwnd, ThumbnailProgressState state)
        {
            TaskbarList.SetProgressState(hwnd, (TBPFLAG)state);
        }
        /// <summary>
        /// Sets the progress value of the specified window's
        /// taskbar button.
        /// </summary>
        /// <param name="hwnd">The window handle.</param>
        /// <param name="current">The current value.</param>
        /// <param name="maximum">The maximum value.</param>
        public static void SetProgressValue(IntPtr hwnd, ulong current, ulong maximum)
        {
            TaskbarList.SetProgressValue(hwnd, current, maximum);
        }

        #endregion

        #region Taskbar Thumbnails

        /// <summary>
        /// Specifies that only a portion of the window's client area
        /// should be used in the window's thumbnail.
        /// </summary>
        /// <param name="hwnd">The window.</param>
        /// <param name="clipRect">The rectangle that specifies the clipped region.</param>
        public static void SetThumbnailClip(IntPtr hwnd, Rectangle clipRect)
        {
            RECT rect = new RECT(clipRect.Left, clipRect.Top, clipRect.Right, clipRect.Bottom);
            TaskbarList.SetThumbnailClip(hwnd, ref rect);
        }

        /// <summary>
        /// Sets the specified window's thumbnail tooltip.
        /// </summary>
        /// <param name="hwnd">The window.</param>
        /// <param name="tooltip">The tooltip text.</param>
        public static void SetThumbnailTooltip(IntPtr hwnd, string tooltip)
        {
            TaskbarList.SetThumbnailTooltip(hwnd, tooltip);
        }

        #endregion

        #region Miscellaneous

        /// <summary>
        /// Specifies that the taskbar- and DWM-related windows messages should
        /// pass through the Windows UIPI mechanism even if the process is
        /// running elevated.  Calling this method is not required unless the
        /// process is running elevated.
        /// </summary>
        public static void AllowTaskbarWindowMessagesThroughUipi()
        {
            UnsafeNativeMethods.ChangeWindowMessageFilter(UnsafeNativeMethods.WM_TaskbarButtonCreated, SafeNativeMethods.MSGFLT_ADD);
            UnsafeNativeMethods.ChangeWindowMessageFilter(SafeNativeMethods.WM_DWMSENDICONICTHUMBNAIL, SafeNativeMethods.MSGFLT_ADD);
            UnsafeNativeMethods.ChangeWindowMessageFilter(SafeNativeMethods.WM_DWMSENDICONICLIVEPREVIEWBITMAP, SafeNativeMethods.MSGFLT_ADD);
            UnsafeNativeMethods.ChangeWindowMessageFilter(SafeNativeMethods.WM_COMMAND, SafeNativeMethods.MSGFLT_ADD);
            UnsafeNativeMethods.ChangeWindowMessageFilter(SafeNativeMethods.WM_SYSCOMMAND, SafeNativeMethods.MSGFLT_ADD);
            UnsafeNativeMethods.ChangeWindowMessageFilter(SafeNativeMethods.WM_ACTIVATE, SafeNativeMethods.MSGFLT_ADD);
        }

        #endregion
    }
}