[gnome-builder] editor: implement VIM style movement keys.

[Christian Hergert <chergert src gnome org>]

commit 9d51eb70673b516c1701d0ac58cdf80d1b2fe588
Author: Christian Hergert <christian hergert me>
Date:   Thu Sep 25 16:37:22 2014 -0700

    editor: implement VIM style movement keys.
    
    Not perfect, but at least it's something. You can move up/down/left/right
    in the normal fashion, except that you need <Alt>. This does not implement
    things as a command stack like VIM does, meaning you can't combine them
    with numbers.
    
    Additionally, another annoyance to fix is that it looses the line offset
    when you move to a shorter line. We need to plumb through storage of the
    original offset when we truncate and fail to get to the same offset.

 src/editor/gb-editor-commands.c       |  115 +++++++++++++++++++++++++++++++++
 src/resources/keybindings/default.ini |    4 +
 2 files changed, 119 insertions(+), 0 deletions(-)
---
diff --git a/src/editor/gb-editor-commands.c b/src/editor/gb-editor-commands.c
index f6a8784..e71df5d 100644
--- a/src/editor/gb-editor-commands.c
+++ b/src/editor/gb-editor-commands.c
@@ -917,6 +917,117 @@ gb_editor_commands_scroll_up (GbEditorWorkspace *workspace,
 }
 
 static void
+gb_editor_commands_move_forward (GbEditorWorkspace *workspace,
+                                 GbEditorTab       *tab)
+{
+  GtkTextBuffer *buffer;
+  GtkTextIter iter;
+  GtkTextMark *insert;
+
+  g_return_if_fail (GB_IS_EDITOR_WORKSPACE (workspace));
+  g_return_if_fail (GB_IS_EDITOR_TAB (tab));
+
+  buffer = GTK_TEXT_BUFFER (tab->priv->document);
+  insert = gtk_text_buffer_get_insert (buffer);
+  gtk_text_buffer_get_iter_at_mark (buffer, &iter, insert);
+
+  if (!gtk_text_iter_ends_line (&iter) && gtk_text_iter_forward_char (&iter))
+    gtk_text_buffer_select_range (buffer, &iter, &iter);
+}
+
+static void
+gb_editor_commands_move_backward (GbEditorWorkspace *workspace,
+                                  GbEditorTab       *tab)
+{
+  GtkTextBuffer *buffer;
+  GtkTextIter iter;
+  GtkTextMark *insert;
+
+  g_return_if_fail (GB_IS_EDITOR_WORKSPACE (workspace));
+  g_return_if_fail (GB_IS_EDITOR_TAB (tab));
+
+  buffer = GTK_TEXT_BUFFER (tab->priv->document);
+  insert = gtk_text_buffer_get_insert (buffer);
+  gtk_text_buffer_get_iter_at_mark (buffer, &iter, insert);
+
+  if (!gtk_text_iter_starts_line (&iter) && gtk_text_iter_backward_char (&iter))
+    gtk_text_buffer_select_range (buffer, &iter, &iter);
+
+  gtk_text_view_scroll_mark_onscreen (GTK_TEXT_VIEW (tab->priv->source_view),
+                                      insert);
+}
+
+static void
+gb_editor_commands_move_up (GbEditorWorkspace *workspace,
+                            GbEditorTab       *tab)
+{
+  GtkTextBuffer *buffer;
+  GtkTextIter iter;
+  GtkTextMark *insert;
+  guint line;
+  guint line_offset;
+  guint i;
+
+  g_return_if_fail (GB_IS_EDITOR_WORKSPACE (workspace));
+  g_return_if_fail (GB_IS_EDITOR_TAB (tab));
+
+  buffer = GTK_TEXT_BUFFER (tab->priv->document);
+  insert = gtk_text_buffer_get_insert (buffer);
+  gtk_text_buffer_get_iter_at_mark (buffer, &iter, insert);
+
+  line = gtk_text_iter_get_line (&iter);
+  line_offset = gtk_text_iter_get_line_offset (&iter);
+
+  if (line == 0)
+    return;
+
+  gtk_text_buffer_get_iter_at_line (buffer, &iter, line - 1);
+  for (i = 0; i < line_offset; i++)
+    if (gtk_text_iter_ends_line (&iter) ||
+        !gtk_text_iter_forward_char (&iter))
+      break;
+
+  gtk_text_buffer_select_range (buffer, &iter, &iter);
+
+  gtk_text_view_scroll_mark_onscreen (GTK_TEXT_VIEW (tab->priv->source_view),
+                                      insert);
+}
+
+static void
+gb_editor_commands_move_down (GbEditorWorkspace *workspace,
+                              GbEditorTab       *tab)
+{
+  GtkTextBuffer *buffer;
+  GtkTextIter iter;
+  GtkTextMark *insert;
+  guint line;
+  guint line_offset;
+  guint i;
+
+  g_return_if_fail (GB_IS_EDITOR_WORKSPACE (workspace));
+  g_return_if_fail (GB_IS_EDITOR_TAB (tab));
+
+  buffer = GTK_TEXT_BUFFER (tab->priv->document);
+  insert = gtk_text_buffer_get_insert (buffer);
+  gtk_text_buffer_get_iter_at_mark (buffer, &iter, insert);
+
+  line = gtk_text_iter_get_line (&iter);
+  line_offset = gtk_text_iter_get_line_offset (&iter);
+
+  gtk_text_buffer_get_iter_at_line (buffer, &iter, line + 1);
+  if (gtk_text_iter_get_line (&iter) == (line + 1))
+    for (i = 0; i < line_offset; i++)
+      if (gtk_text_iter_ends_line (&iter) ||
+          !gtk_text_iter_forward_char (&iter))
+        break;
+
+  gtk_text_buffer_select_range (buffer, &iter, &iter);
+
+  gtk_text_view_scroll_mark_onscreen (GTK_TEXT_VIEW (tab->priv->source_view),
+                                      insert);
+}
+
+static void
 gb_editor_commands_highlight_mode (GSimpleAction     *action,
                                    GVariant          *parameter,
                                    GbEditorWorkspace *workspace)
@@ -1001,6 +1112,10 @@ gb_editor_commands_init (GbEditorWorkspace *workspace)
     { "trim-trailing-space", gb_editor_commands_trim_trailing_space, TRUE },
     { "scroll-down",         gb_editor_commands_scroll_down,         TRUE },
     { "scroll-up",           gb_editor_commands_scroll_up,           TRUE },
+    { "move-forward",        gb_editor_commands_move_forward,        TRUE },
+    { "move-backward",       gb_editor_commands_move_backward,       TRUE },
+    { "move-up",             gb_editor_commands_move_up,             TRUE },
+    { "move-down",           gb_editor_commands_move_down,           TRUE },
     { NULL }
   };
   GSimpleAction *action;
diff --git a/src/resources/keybindings/default.ini b/src/resources/keybindings/default.ini
index d4b4985..8e1466b 100644
--- a/src/resources/keybindings/default.ini
+++ b/src/resources/keybindings/default.ini
@@ -25,3 +25,7 @@ toggle-preview = <Control><Alt>P
 select-line = <Control>L
 scroll-up = <Control>Y
 scroll-down = <Control>E
+move-up = <Alt>K
+move-down = <Alt>J
+move-forward = <Alt>L
+move-backward = <Alt>H