source: trunk/HeuristicLab.ExtLibs/HeuristicLab.AvalonEdit/5.0.1/AvalonEdit-5.0.1/Editing/ImeNativeWrapper.cs

// Copyright (c) 2014 AlphaSierraPapa for the SharpDevelop Team
// 
// Permission is hereby granted, free of charge, to any person obtaining a copy of this
// software and associated documentation files (the "Software"), to deal in the Software
// without restriction, including without limitation the rights to use, copy, modify, merge,
// publish, distribute, sublicense, and/or sell copies of the Software, and to permit persons
// to whom the Software is furnished to do so, subject to the following conditions:
// 
// The above copyright notice and this permission notice shall be included in all copies or
// substantial portions of the Software.
// 
// THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR IMPLIED,
// INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, FITNESS FOR A PARTICULAR
// PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE
// FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR
// OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER
// DEALINGS IN THE SOFTWARE.

using System;
using System.Linq;
using System.Runtime.CompilerServices;
using System.Runtime.InteropServices;
using System.Security;
using System.Windows;
using System.Windows.Input;
using System.Windows.Interop;
using System.Windows.Media;
using System.Windows.Media.TextFormatting;

using ICSharpCode.AvalonEdit;
using ICSharpCode.AvalonEdit.Document;
using ICSharpCode.AvalonEdit.Rendering;
using ICSharpCode.AvalonEdit.Utils;
using Draw = System.Drawing;

namespace ICSharpCode.AvalonEdit.Editing
{
  /// <summary>
  /// Native API required for IME support.
  /// </summary>
  static class ImeNativeWrapper
  {
    [StructLayout(LayoutKind.Sequential)]
    struct CompositionForm
    {
      public int dwStyle;
      public POINT ptCurrentPos;
      public RECT rcArea;
    }
    
    [StructLayout(LayoutKind.Sequential)]
    struct POINT
    {
      public int x;
      public int y;
    }
    
    [StructLayout(LayoutKind.Sequential)]
    struct RECT
    {
      public int left;
      public int top;
      public int right;
      public int bottom;
    }
    
    [StructLayout(LayoutKind.Sequential, CharSet=CharSet.Unicode)]
    struct LOGFONT
    {
      public int lfHeight;
      public int lfWidth;
      public int lfEscapement;
      public int lfOrientation;
      public int lfWeight;
      public byte lfItalic;
      public byte lfUnderline;
      public byte lfStrikeOut;
      public byte lfCharSet;
      public byte lfOutPrecision;
      public byte lfClipPrecision;
      public byte lfQuality;
      public byte lfPitchAndFamily;
      [MarshalAs(UnmanagedType.ByValTStr, SizeConst=32)] public string lfFaceName;
    }
    
    const int CPS_CANCEL = 0x4;
    const int NI_COMPOSITIONSTR = 0x15;
    const int GCS_COMPSTR = 0x0008;
    
    public const int WM_IME_COMPOSITION = 0x10F;
    public const int WM_IME_SETCONTEXT = 0x281;
    public const int WM_INPUTLANGCHANGE = 0x51;
    
    [DllImport("imm32.dll")]
    public static extern IntPtr ImmAssociateContext(IntPtr hWnd, IntPtr hIMC);
    [DllImport("imm32.dll")]
    internal static extern IntPtr ImmGetContext(IntPtr hWnd);
    [DllImport("imm32.dll")]
    internal static extern IntPtr ImmGetDefaultIMEWnd(IntPtr hWnd);
    [DllImport("imm32.dll")]
    [return: MarshalAs(UnmanagedType.Bool)]
    internal static extern bool ImmReleaseContext(IntPtr hWnd, IntPtr hIMC);
    [DllImport("imm32.dll")]
    [return: MarshalAs(UnmanagedType.Bool)]
    static extern bool ImmNotifyIME(IntPtr hIMC, int dwAction, int dwIndex, int dwValue = 0);
    [DllImport("imm32.dll")]
    [return: MarshalAs(UnmanagedType.Bool)]
    static extern bool ImmSetCompositionWindow(IntPtr hIMC, ref CompositionForm form);
    [DllImport("imm32.dll", CharSet = CharSet.Unicode)]
    [return: MarshalAs(UnmanagedType.Bool)]
    static extern bool ImmSetCompositionFont(IntPtr hIMC, ref LOGFONT font);
    [DllImport("imm32.dll")]
    [return: MarshalAs(UnmanagedType.Bool)]
    static extern bool ImmGetCompositionFont(IntPtr hIMC, out LOGFONT font);
    
    [DllImport("msctf.dll")]
    static extern int TF_CreateThreadMgr(out ITfThreadMgr threadMgr);
    
    [ThreadStatic] static bool textFrameworkThreadMgrInitialized;
    [ThreadStatic] static ITfThreadMgr textFrameworkThreadMgr;
    
    public static ITfThreadMgr GetTextFrameworkThreadManager()
    {
      if (!textFrameworkThreadMgrInitialized) {
        textFrameworkThreadMgrInitialized = true;
        TF_CreateThreadMgr(out textFrameworkThreadMgr);
      }
      return textFrameworkThreadMgr;
    }
    
    public static bool NotifyIme(IntPtr hIMC)
    {
      return ImmNotifyIME(hIMC, NI_COMPOSITIONSTR, CPS_CANCEL);
    }
    
    public static bool SetCompositionWindow(HwndSource source, IntPtr hIMC, TextArea textArea)
    {
      if (textArea == null)
        throw new ArgumentNullException("textArea");
      Rect textViewBounds = textArea.TextView.GetBounds(source);
      Rect characterBounds = textArea.TextView.GetCharacterBounds(textArea.Caret.Position, source);
      CompositionForm form = new CompositionForm();
      form.dwStyle = 0x0020;
      form.ptCurrentPos.x = (int)Math.Max(characterBounds.Left, textViewBounds.Left);
      form.ptCurrentPos.y = (int)Math.Max(characterBounds.Top, textViewBounds.Top);
      form.rcArea.left = (int)textViewBounds.Left;
      form.rcArea.top = (int)textViewBounds.Top;
      form.rcArea.right = (int)textViewBounds.Right;
      form.rcArea.bottom = (int)textViewBounds.Bottom;
      return ImmSetCompositionWindow(hIMC, ref form);
    }
    
    public static bool SetCompositionFont(HwndSource source, IntPtr hIMC, TextArea textArea)
    {
      if (textArea == null)
        throw new ArgumentNullException("textArea");
      LOGFONT lf = new LOGFONT();
      Rect characterBounds = textArea.TextView.GetCharacterBounds(textArea.Caret.Position, source);
      lf.lfFaceName = textArea.FontFamily.Source;
      lf.lfHeight = (int)characterBounds.Height;
      return ImmSetCompositionFont(hIMC, ref lf);
    }
    
    static Rect GetBounds(this TextView textView, HwndSource source)
    {
      // this may happen during layout changes in AvalonDock, so we just return an empty rectangle
      // in those cases. It should be refreshed immediately.
      if (source.RootVisual == null || !source.RootVisual.IsAncestorOf(textView))
        return EMPTY_RECT;
      Rect displayRect = new Rect(0, 0, textView.ActualWidth, textView.ActualHeight);
      return textView
        .TransformToAncestor(source.RootVisual).TransformBounds(displayRect) // rect on root visual
        .TransformToDevice(source.RootVisual); // rect on HWND
    }
    
    static readonly Rect EMPTY_RECT = new Rect(0, 0, 0, 0);
    
    static Rect GetCharacterBounds(this TextView textView, TextViewPosition pos, HwndSource source)
    {
      VisualLine vl = textView.GetVisualLine(pos.Line);
      if (vl == null)
        return EMPTY_RECT;
      // this may happen during layout changes in AvalonDock, so we just return an empty rectangle
      // in those cases. It should be refreshed immediately.
      if (source.RootVisual == null || !source.RootVisual.IsAncestorOf(textView))
        return EMPTY_RECT;
      TextLine line = vl.GetTextLine(pos.VisualColumn, pos.IsAtEndOfLine);
      Rect displayRect;
      // calculate the display rect for the current character
      if (pos.VisualColumn < vl.VisualLengthWithEndOfLineMarker) {
        displayRect = line.GetTextBounds(pos.VisualColumn, 1).First().Rectangle;
        displayRect.Offset(0, vl.GetTextLineVisualYPosition(line, VisualYPosition.LineTop));
      } else {
        // if we are in virtual space, we just use one wide-space as character width
        displayRect = new Rect(vl.GetVisualPosition(pos.VisualColumn, VisualYPosition.TextTop),
                               new Size(textView.WideSpaceWidth, textView.DefaultLineHeight));
      }
      // adjust to current scrolling
      displayRect.Offset(-textView.ScrollOffset);
      return textView
        .TransformToAncestor(source.RootVisual).TransformBounds(displayRect) // rect on root visual
        .TransformToDevice(source.RootVisual); // rect on HWND
    }
  }
  
  [ComImport, Guid("aa80e801-2021-11d2-93e0-0060b067b86e"), InterfaceType(ComInterfaceType.InterfaceIsIUnknown)]
  interface ITfThreadMgr
  {
    void Activate(out int clientId);
    void Deactivate();
    void CreateDocumentMgr(out IntPtr docMgr);
    void EnumDocumentMgrs(out IntPtr enumDocMgrs);
    void GetFocus(out IntPtr docMgr);
    void SetFocus(IntPtr docMgr);
    void AssociateFocus(IntPtr hwnd, IntPtr newDocMgr, out IntPtr prevDocMgr);
    void IsThreadFocus([MarshalAs(UnmanagedType.Bool)] out bool isFocus);
    void GetFunctionProvider(ref Guid classId, out IntPtr funcProvider);
    void EnumFunctionProviders(out IntPtr enumProviders);
    void GetGlobalCompartment(out IntPtr compartmentMgr);
  }
}