widget/gtk/NativeKeyBindings.cpp
author Masayuki Nakano <masayuki@d-toybox.com>
Fri, 19 May 2017 17:49:41 +0900
changeset 407399 b75c111837a802ceb953dba50a3c5a193d53ca22
parent 336533 b3c7c85f2f8ac2a669ecec5570bba22ff83b4a99
child 417644 bf0251c25bbb39ef3d21689b4a87d46e30b3dcdf
permissions -rw-r--r--
Bug 1339543 part 4 Change nsIWidget::ExecuteNativeKeyBinding() to nsIWidget::GetEditCommands() which just retrieves edit commands for the type r=smaug Now, nsIWidget::ExecuteNativeKeyBinding() isn't used by anybody for executing edit commands. Instead, they need array of edit commands for the key combination. So, the method should be renamed to GetEditCommands() and just return edit commands as an array. MozReview-Commit-ID: 4G0B1lJ8Lbe

/* -*- Mode: C++; tab-width: 2; indent-tabs-mode: nil; c-basic-offset: 2 -*- */
/* This Source Code Form is subject to the terms of the Mozilla Public
 * License, v. 2.0. If a copy of the MPL was not distributed with this
 * file, You can obtain one at http://mozilla.org/MPL/2.0/. */

#include "mozilla/ArrayUtils.h"
#include "mozilla/MathAlgorithms.h"
#include "mozilla/TextEvents.h"

#include "NativeKeyBindings.h"
#include "nsString.h"
#include "nsMemory.h"
#include "nsGtkKeyUtils.h"

#include <gtk/gtk.h>
#include <gdk/gdkkeysyms.h>
#include <gdk/gdk.h>

namespace mozilla {
namespace widget {

static nsTArray<CommandInt>* gCurrentCommands = nullptr;
static bool gHandled = false;

// Common GtkEntry and GtkTextView signals
static void
copy_clipboard_cb(GtkWidget *w, gpointer user_data)
{
  gCurrentCommands->AppendElement(CommandCopy);
  g_signal_stop_emission_by_name(w, "copy_clipboard");
  gHandled = true;
}

static void
cut_clipboard_cb(GtkWidget *w, gpointer user_data)
{
  gCurrentCommands->AppendElement(CommandCut);
  g_signal_stop_emission_by_name(w, "cut_clipboard");
  gHandled = true;
}

// GTK distinguishes between display lines (wrapped, as they appear on the
// screen) and paragraphs, which are runs of text terminated by a newline.
// We don't have this distinction, so we always use editor's notion of
// lines, which are newline-terminated.

static const Command sDeleteCommands[][2] = {
  // backward, forward
  { CommandDeleteCharBackward, CommandDeleteCharForward },    // CHARS
  { CommandDeleteWordBackward, CommandDeleteWordForward },    // WORD_ENDS
  { CommandDeleteWordBackward, CommandDeleteWordForward },    // WORDS
  { CommandDeleteToBeginningOfLine, CommandDeleteToEndOfLine }, // LINES
  { CommandDeleteToBeginningOfLine, CommandDeleteToEndOfLine }, // LINE_ENDS
  { CommandDeleteToBeginningOfLine, CommandDeleteToEndOfLine }, // PARAGRAPH_ENDS
  { CommandDeleteToBeginningOfLine, CommandDeleteToEndOfLine }, // PARAGRAPHS
  // This deletes from the end of the previous word to the beginning of the
  // next word, but only if the caret is not in a word.
  // XXX need to implement in editor
  { CommandDoNothing, CommandDoNothing } // WHITESPACE
};

static void
delete_from_cursor_cb(GtkWidget *w, GtkDeleteType del_type,
                      gint count, gpointer user_data)
{
  g_signal_stop_emission_by_name(w, "delete_from_cursor");
  bool forward = count > 0;

#if (MOZ_WIDGET_GTK == 3)
  // Ignore GTK's Ctrl-K keybinding introduced in GTK 3.14 and removed in
  // 3.18 if the user has custom bindings set. See bug 1176929.
  if (del_type == GTK_DELETE_PARAGRAPH_ENDS && forward && GTK_IS_ENTRY(w) &&
      !gtk_check_version(3, 14, 1) && gtk_check_version(3, 17, 9)) {
    GtkStyleContext* context = gtk_widget_get_style_context(w);
    GtkStateFlags flags = gtk_widget_get_state_flags(w);

    GPtrArray* array;
    gtk_style_context_get(context, flags, "gtk-key-bindings", &array, nullptr);
    if (!array)
      return;
    g_ptr_array_unref(array);
  }
#endif

  gHandled = true;
  if (uint32_t(del_type) >= ArrayLength(sDeleteCommands)) {
    // unsupported deletion type
    return;
  }

  if (del_type == GTK_DELETE_WORDS) {
    // This works like word_ends, except we first move the caret to the
    // beginning/end of the current word.
    if (forward) {
      gCurrentCommands->AppendElement(CommandWordNext);
      gCurrentCommands->AppendElement(CommandWordPrevious);
    } else {
      gCurrentCommands->AppendElement(CommandWordPrevious);
      gCurrentCommands->AppendElement(CommandWordNext);
    }
  } else if (del_type == GTK_DELETE_DISPLAY_LINES ||
             del_type == GTK_DELETE_PARAGRAPHS) {

    // This works like display_line_ends, except we first move the caret to the
    // beginning/end of the current line.
    if (forward) {
      gCurrentCommands->AppendElement(CommandBeginLine);
    } else {
      gCurrentCommands->AppendElement(CommandEndLine);
    }
  }

  Command command = sDeleteCommands[del_type][forward];
  if (!command) {
    return; // unsupported command
  }

  unsigned int absCount = Abs(count);
  for (unsigned int i = 0; i < absCount; ++i) {
    gCurrentCommands->AppendElement(command);
  }
}

static const Command sMoveCommands[][2][2] = {
  // non-extend { backward, forward }, extend { backward, forward }
  // GTK differentiates between logical position, which is prev/next,
  // and visual position, which is always left/right.
  // We should fix this to work the same way for RTL text input.
  { // LOGICAL_POSITIONS
    { CommandCharPrevious, CommandCharNext },
    { CommandSelectCharPrevious, CommandSelectCharNext }
  },
  { // VISUAL_POSITIONS
    { CommandCharPrevious, CommandCharNext },
    { CommandSelectCharPrevious, CommandSelectCharNext }
  },
  { // WORDS
    { CommandWordPrevious, CommandWordNext },
    { CommandSelectWordPrevious, CommandSelectWordNext }
  },
  { // DISPLAY_LINES
    { CommandLinePrevious, CommandLineNext },
    { CommandSelectLinePrevious, CommandSelectLineNext }
  },
  { // DISPLAY_LINE_ENDS
    { CommandBeginLine, CommandEndLine },
    { CommandSelectBeginLine, CommandSelectEndLine }
  },
  { // PARAGRAPHS
    { CommandLinePrevious, CommandLineNext },
    { CommandSelectLinePrevious, CommandSelectLineNext }
  },
  { // PARAGRAPH_ENDS
    { CommandBeginLine, CommandEndLine },
    { CommandSelectBeginLine, CommandSelectEndLine }
  },
  { // PAGES
    { CommandMovePageUp, CommandMovePageDown },
    { CommandSelectPageUp, CommandSelectPageDown }
  },
  { // BUFFER_ENDS
    { CommandMoveTop, CommandMoveBottom },
    { CommandSelectTop, CommandSelectBottom }
  },
  { // HORIZONTAL_PAGES (unsupported)
    { CommandDoNothing, CommandDoNothing },
    { CommandDoNothing, CommandDoNothing }
  }
};

static void
move_cursor_cb(GtkWidget *w, GtkMovementStep step, gint count,
               gboolean extend_selection, gpointer user_data)
{
  g_signal_stop_emission_by_name(w, "move_cursor");
  gHandled = true;
  bool forward = count > 0;
  if (uint32_t(step) >= ArrayLength(sMoveCommands)) {
    // unsupported movement type
    return;
  }

  Command command = sMoveCommands[step][extend_selection][forward];
  if (!command) {
    return; // unsupported command
  }

  unsigned int absCount = Abs(count);
  for (unsigned int i = 0; i < absCount; ++i) {
    gCurrentCommands->AppendElement(command);
  }
}

static void
paste_clipboard_cb(GtkWidget *w, gpointer user_data)
{
  gCurrentCommands->AppendElement(CommandPaste);
  g_signal_stop_emission_by_name(w, "paste_clipboard");
  gHandled = true;
}

// GtkTextView-only signals
static void
select_all_cb(GtkWidget *w, gboolean select, gpointer user_data)
{
  gCurrentCommands->AppendElement(CommandSelectAll);
  g_signal_stop_emission_by_name(w, "select_all");
  gHandled = true;
}

NativeKeyBindings* NativeKeyBindings::sInstanceForSingleLineEditor = nullptr;
NativeKeyBindings* NativeKeyBindings::sInstanceForMultiLineEditor = nullptr;

// static
NativeKeyBindings*
NativeKeyBindings::GetInstance(NativeKeyBindingsType aType)
{
  switch (aType) {
    case nsIWidget::NativeKeyBindingsForSingleLineEditor:
      if (!sInstanceForSingleLineEditor) {
        sInstanceForSingleLineEditor = new NativeKeyBindings();
        sInstanceForSingleLineEditor->Init(aType);
      }
      return sInstanceForSingleLineEditor;

    default:
      // fallback to multiline editor case in release build
      MOZ_FALLTHROUGH_ASSERT("aType is invalid or not yet implemented");
    case nsIWidget::NativeKeyBindingsForMultiLineEditor:
    case nsIWidget::NativeKeyBindingsForRichTextEditor:
      if (!sInstanceForMultiLineEditor) {
        sInstanceForMultiLineEditor = new NativeKeyBindings();
        sInstanceForMultiLineEditor->Init(aType);
      }
      return sInstanceForMultiLineEditor;
  }
}

// static
void
NativeKeyBindings::Shutdown()
{
  delete sInstanceForSingleLineEditor;
  sInstanceForSingleLineEditor = nullptr;
  delete sInstanceForMultiLineEditor;
  sInstanceForMultiLineEditor = nullptr;
}

void
NativeKeyBindings::Init(NativeKeyBindingsType  aType)
{
  switch (aType) {
  case nsIWidget::NativeKeyBindingsForSingleLineEditor:
    mNativeTarget = gtk_entry_new();
    break;
  default:
    mNativeTarget = gtk_text_view_new();
    if (gtk_major_version > 2 ||
        (gtk_major_version == 2 && (gtk_minor_version > 2 ||
                                    (gtk_minor_version == 2 &&
                                     gtk_micro_version >= 2)))) {
      // select_all only exists in gtk >= 2.2.2.  Prior to that,
      // ctrl+a is bound to (move to beginning, select to end).
      g_signal_connect(mNativeTarget, "select_all",
                       G_CALLBACK(select_all_cb), this);
    }
    break;
  }

  g_object_ref_sink(mNativeTarget);

  g_signal_connect(mNativeTarget, "copy_clipboard",
                   G_CALLBACK(copy_clipboard_cb), this);
  g_signal_connect(mNativeTarget, "cut_clipboard",
                   G_CALLBACK(cut_clipboard_cb), this);
  g_signal_connect(mNativeTarget, "delete_from_cursor",
                   G_CALLBACK(delete_from_cursor_cb), this);
  g_signal_connect(mNativeTarget, "move_cursor",
                   G_CALLBACK(move_cursor_cb), this);
  g_signal_connect(mNativeTarget, "paste_clipboard",
                   G_CALLBACK(paste_clipboard_cb), this);
}

NativeKeyBindings::~NativeKeyBindings()
{
  gtk_widget_destroy(mNativeTarget);
  g_object_unref(mNativeTarget);
}

void
NativeKeyBindings::GetEditCommands(const WidgetKeyboardEvent& aEvent,
                                   nsTArray<CommandInt>& aCommands)
{
  // If the native key event is set, it must be synthesized for tests.
  // We just ignore such events because this behavior depends on system
  // settings.
  if (!aEvent.mNativeKeyEvent) {
    // It must be synthesized event or dispatched DOM event from chrome.
    return;
  }

  guint keyval;

  if (aEvent.mCharCode) {
    keyval = gdk_unicode_to_keyval(aEvent.mCharCode);
  } else {
    keyval =
      static_cast<GdkEventKey*>(aEvent.mNativeKeyEvent)->keyval;
  }

  if (GetEditCommandsInternal(aEvent, aCommands, keyval)) {
    return;
  }

  for (uint32_t i = 0; i < aEvent.mAlternativeCharCodes.Length(); ++i) {
    uint32_t ch = aEvent.IsShift() ?
      aEvent.mAlternativeCharCodes[i].mShiftedCharCode :
      aEvent.mAlternativeCharCodes[i].mUnshiftedCharCode;
    if (ch && ch != aEvent.mCharCode) {
      keyval = gdk_unicode_to_keyval(ch);
      if (GetEditCommandsInternal(aEvent, aCommands, keyval)) {
        return;
      }
    }
  }

/*
gtk_bindings_activate_event is preferable, but it has unresolved bug:
http://bugzilla.gnome.org/show_bug.cgi?id=162726
The bug was already marked as FIXED.  However, somebody reports that the
bug still exists.
Also gtk_bindings_activate may work with some non-shortcuts operations
(todo: check it). See bug 411005 and bug 406407.

Code, which should be used after fixing GNOME bug 162726:

  gtk_bindings_activate_event(GTK_OBJECT(mNativeTarget),
    static_cast<GdkEventKey*>(aEvent.mNativeKeyEvent));
*/
}

bool
NativeKeyBindings::GetEditCommandsInternal(const WidgetKeyboardEvent& aEvent,
                                           nsTArray<CommandInt>& aCommands,
                                           guint aKeyval)
{
  guint modifiers =
    static_cast<GdkEventKey*>(aEvent.mNativeKeyEvent)->state;

  gCurrentCommands = &aCommands;

  gHandled = false;
#if (MOZ_WIDGET_GTK == 2)
  gtk_bindings_activate(GTK_OBJECT(mNativeTarget),
                        aKeyval, GdkModifierType(modifiers));
#else
  gtk_bindings_activate(G_OBJECT(mNativeTarget),
                        aKeyval, GdkModifierType(modifiers));
#endif

  gCurrentCommands = nullptr;

  MOZ_ASSERT(!gHandled || !aCommands.IsEmpty());

  return gHandled;
}

} // namespace widget
} // namespace mozilla