[evolution/gnome-3-16] Bug 748217 - undo of Ctrl-Backspace and Ctrl-Delete is broken for multi-character strings

[Tomas Popela <tpopela src gnome org>]

commit bfa1117b4dbaad5c4a22a0b6417c13ca0e4e9ab4
Author: Tomas Popela <tpopela redhat com>
Date:   Tue Apr 21 13:22:48 2015 +0200

    Bug 748217 - undo of Ctrl-Backspace and Ctrl-Delete is broken for multi-character strings
    
    Correct the current undo/redo implementation of delete operation to handle
    the Ctrl+Backspace and Ctrl+Delete cases.

 e-util/e-html-editor-view.c |  161 ++++++++++++++++++++++++++++++-------------
 1 files changed, 114 insertions(+), 47 deletions(-)
---
diff --git a/e-util/e-html-editor-view.c b/e-util/e-html-editor-view.c
index eec8244..9a0cf33 100644
--- a/e-util/e-html-editor-view.c
+++ b/e-util/e-html-editor-view.c
@@ -4114,7 +4114,8 @@ fix_structure_after_delete_before_quoted_content (EHTMLEditorView *view)
 
 static void
 save_history_for_delete_or_backspace (EHTMLEditorView *view,
-                                      gboolean delete_key)
+                                      gboolean delete_key,
+                                      gboolean control_key)
 {
        EHTMLEditorSelection *selection;
        EHTMLEditorViewHistoryEvent *ev;
@@ -4158,46 +4159,98 @@ save_history_for_delete_or_backspace (EHTMLEditorView *view,
                block_selection_changed_callbacks (view);
 
                range_clone = webkit_dom_range_clone_range (range, NULL);
-               if (delete_key) {
-                       glong offset = webkit_dom_range_get_start_offset (range_clone, NULL);
-                       webkit_dom_range_set_end (
-                               range_clone,
-                               webkit_dom_range_get_end_container (range_clone, NULL),
-                               offset + 1,
-                               NULL);
+               if (control_key) {
+                       WebKitDOMRange *tmp_range;
+
+                       /* Control + Delete/Backspace deletes previous/next word. */
+                       webkit_dom_dom_selection_modify (
+                               dom_selection, "move", delete_key ? "right" : "left", "word");
+                       tmp_range = webkit_dom_dom_selection_get_range_at (dom_selection, 0, NULL);
+                       if (delete_key)
+                               webkit_dom_range_set_end (
+                                       range_clone,
+                                       webkit_dom_range_get_end_container (tmp_range, NULL),
+                                       webkit_dom_range_get_end_offset (tmp_range, NULL),
+                                       NULL);
+                       else
+                               webkit_dom_range_set_start (
+                                       range_clone,
+                                       webkit_dom_range_get_start_container (tmp_range, NULL),
+                                       webkit_dom_range_get_start_offset (tmp_range, NULL),
+                                       NULL);
+                       g_object_unref (tmp_range);
                } else {
-                       webkit_dom_range_set_start (
-                               range_clone,
-                               webkit_dom_range_get_start_container (range_clone, NULL),
-                               webkit_dom_range_get_start_offset (range_clone, NULL) - 1,
-                               NULL);
+                       if (delete_key) {
+                               glong offset = webkit_dom_range_get_start_offset (range_clone, NULL);
+                               webkit_dom_range_set_end (
+                                       range_clone,
+                                       webkit_dom_range_get_end_container (range_clone, NULL),
+                                       offset + 1,
+                                       NULL);
+                       } else {
+                               webkit_dom_range_set_start (
+                                       range_clone,
+                                       webkit_dom_range_get_start_container (range_clone, NULL),
+                                       webkit_dom_range_get_start_offset (range_clone, NULL) - 1,
+                                       NULL);
+                       }
                }
 
                fragment = webkit_dom_range_clone_contents (range_clone, NULL);
-               g_object_unref (range_clone);
                if (!webkit_dom_node_get_first_child (WEBKIT_DOM_NODE (fragment))) {
                        g_free (ev);
                        unblock_selection_changed_callbacks (view);
                        g_object_unref (range);
+                       g_object_unref (range_clone);
                        g_object_unref (dom_selection);
                        return;
                }
 
-               if (delete_key) {
-                       e_html_editor_selection_get_selection_coordinates (
-                               selection, &ev->after.start.x, &ev->after.start.y, &ev->after.end.x, 
&ev->after.end.y);
+               if (control_key) {
+                       if (delete_key) {
+                               ev->after.start.x = ev->before.start.x;
+                               ev->after.start.y = ev->before.start.y;
+                               ev->after.end.x = ev->before.end.x;
+                               ev->after.end.y = ev->before.end.y;
+
+                               webkit_dom_range_collapse (range_clone, TRUE, NULL);
+                               webkit_dom_dom_selection_remove_all_ranges (dom_selection);
+                               webkit_dom_dom_selection_add_range (dom_selection, range_clone);
+                       } else {
+                               WebKitDOMRange *tmp_range;
+
+                               tmp_range = webkit_dom_range_clone_range (range_clone, NULL);
+                               /* Prepare the selection to the right position after
+                                * delete and save it. */
+                               webkit_dom_range_collapse (range_clone, TRUE, NULL);
+                               webkit_dom_dom_selection_remove_all_ranges (dom_selection);
+                               webkit_dom_dom_selection_add_range (dom_selection, range_clone);
+                               e_html_editor_selection_get_selection_coordinates (
+                                       selection, &ev->after.start.x, &ev->after.start.y, &ev->after.end.x, 
&ev->after.end.y);
+                               /* Restore the selection where it was before the
+                                * history event was saved. */
+                               webkit_dom_range_collapse (tmp_range, FALSE, NULL);
+                               webkit_dom_dom_selection_remove_all_ranges (dom_selection);
+                               webkit_dom_dom_selection_add_range (dom_selection, tmp_range);
+                               g_object_unref (tmp_range);
+                       }
                } else {
-                       webkit_dom_dom_selection_modify (dom_selection, "move", "left", "character");
-                       e_html_editor_selection_get_selection_coordinates (
-                               selection, &ev->after.start.x, &ev->after.start.y, &ev->after.end.x, 
&ev->after.end.y);
-                       webkit_dom_dom_selection_modify (dom_selection, "move", "right", "character");
-               }
+                       if (delete_key) {
+                               e_html_editor_selection_get_selection_coordinates (
+                                       selection, &ev->after.start.x, &ev->after.start.y, &ev->after.end.x, 
&ev->after.end.y);
+                       } else {
+                               webkit_dom_dom_selection_modify (dom_selection, "move", "left", "character");
+                               e_html_editor_selection_get_selection_coordinates (
+                                       selection, &ev->after.start.x, &ev->after.start.y, &ev->after.end.x, 
&ev->after.end.y);
+                               webkit_dom_dom_selection_modify (dom_selection, "move", "right", "character");
 
-               if (!delete_key) {
-                       ev->after.end.x = ev->after.start.x;
-                       ev->after.end.y = ev->after.start.y;
+                               ev->after.end.x = ev->after.start.x;
+                               ev->after.end.y = ev->after.start.y;
+                       }
                }
 
+               g_object_unref (range_clone);
+
                if (delete_key) {
                        webkit_dom_node_insert_before (
                                WEBKIT_DOM_NODE (fragment),
@@ -4716,7 +4769,8 @@ html_editor_view_key_press_event (GtkWidget *widget,
                        }
                        e_html_editor_selection_restore (view->priv->selection);
                }
-               save_history_for_delete_or_backspace (view, event->keyval == GDK_KEY_Delete);
+               save_history_for_delete_or_backspace (
+                       view, event->keyval == GDK_KEY_Delete, ((event)->state & GDK_CONTROL_MASK));
                if (event->keyval == GDK_KEY_BackSpace && !view->priv->html_mode) {
                        if (delete_character_from_quoted_line_start (view))
                                return TRUE;
@@ -11007,6 +11061,7 @@ static void
 undo_delete (EHTMLEditorView *view,
             EHTMLEditorViewHistoryEvent *event)
 {
+       EHTMLEditorSelection *selection;
        gboolean empty, single_block;
        gchar *content;
        WebKitDOMDocument *document;
@@ -11016,6 +11071,8 @@ undo_delete (EHTMLEditorView *view,
        WebKitDOMElement *element;
        WebKitDOMNode *first_child, *fragment;
 
+       selection = e_html_editor_view_get_selection (view);
+
        document = webkit_web_view_get_dom_document (WEBKIT_WEB_VIEW (view));
        dom_window = webkit_dom_document_get_default_view (document);
        dom_selection = webkit_dom_dom_window_get_selection (dom_window);
@@ -11042,11 +11099,8 @@ undo_delete (EHTMLEditorView *view,
 
        /* Redoing Return key press */
        if (empty) {
-               EHTMLEditorSelection *selection;
                WebKitDOMNode *node;
 
-               selection = e_html_editor_view_get_selection (view);
-
                range = get_range_for_point (document, event->before.start);
                webkit_dom_dom_selection_remove_all_ranges (dom_selection);
                webkit_dom_dom_selection_add_range (dom_selection, range);
@@ -11071,14 +11125,11 @@ undo_delete (EHTMLEditorView *view,
 
        /* Multi block delete */
        if (WEBKIT_DOM_IS_ELEMENT (first_child) && !single_block) {
-               EHTMLEditorSelection *selection;
                WebKitDOMNode *node, *parent, *last_child;
                WebKitDOMNode *parent_deleted_content;
                WebKitDOMNode *parent_current_block;
                WebKitDOMNode *insert_before;
 
-               selection = e_html_editor_view_get_selection (view);
-
                range = get_range_for_point (document, event->before.start);
                webkit_dom_dom_selection_remove_all_ranges (dom_selection);
                webkit_dom_dom_selection_add_range (dom_selection, range);
@@ -11188,7 +11239,7 @@ undo_delete (EHTMLEditorView *view,
                 * otherwise the selection was not callapsed so select the deleted
                 * content as it was before the delete occured. */
                if (webkit_dom_document_fragment_query_selector (event->data.fragment, 
"span#-x-evo-selection-start-marker", NULL))
-                       e_html_editor_selection_restore (e_html_editor_view_get_selection (view));
+                       e_html_editor_selection_restore (selection);
                else
                        restore_selection_to_history_event_state (view, event->before);
 
@@ -11201,6 +11252,12 @@ undo_delete (EHTMLEditorView *view,
        g_object_unref (dom_selection);
 }
 
+static gboolean
+event_selection_was_collapsed (EHTMLEditorViewHistoryEvent *ev)
+{
+       return (ev->before.start.x == ev->before.end.x) && (ev->before.start.y == ev->before.end.y);
+}
+
 static void
 redo_delete (EHTMLEditorView *view,
             EHTMLEditorViewHistoryEvent *event)
@@ -11216,7 +11273,9 @@ redo_delete (EHTMLEditorView *view,
        restore_selection_to_history_event_state (view, event->before);
 
        if (webkit_dom_document_fragment_query_selector (fragment, "span#-x-evo-selection-start-marker", 
NULL)) {
-               gboolean delete = FALSE;
+               gboolean delete = FALSE, control_key = FALSE;
+               glong length = 1;
+               gint ii;
                WebKitDOMDOMWindow *dom_window;
                WebKitDOMDOMSelection *dom_selection;
 
@@ -11224,18 +11283,32 @@ redo_delete (EHTMLEditorView *view,
                g_object_unref (dom_window);
                dom_selection = webkit_dom_dom_window_get_selection (dom_window);
 
+               control_key = event_selection_was_collapsed (event);
+               if (control_key) {
+                       gchar *text_content;
+
+                       text_content = webkit_dom_node_get_text_content (WEBKIT_DOM_NODE (fragment));
+                       length = g_utf8_strlen (text_content, -1);
+                       control_key = control_key && length > 1;
+
+                       g_free (text_content);
+               }
+
                /* Check if the event was delete or backspace press. */
                delete = WEBKIT_DOM_IS_ELEMENT (first_child);
                delete = delete && element_has_id (WEBKIT_DOM_ELEMENT (first_child), 
"-x-evo-selection-start-marker");
-               if (delete)
-                       webkit_dom_dom_selection_modify (dom_selection, "extend", "right", "character");
-               else
-                       webkit_dom_dom_selection_modify (dom_selection, "extend", "left", "character");
 
-               g_object_unref (dom_selection);
-       }
+               for (ii = 0; ii < length; ii++) {
+                       e_html_editor_view_exec_command (
+                               view,
+                               delete ? E_HTML_EDITOR_VIEW_COMMAND_FORWARD_DELETE :
+                                        E_HTML_EDITOR_VIEW_COMMAND_DELETE,
+                               NULL);
+               }
 
-       e_html_editor_view_exec_command (view, E_HTML_EDITOR_VIEW_COMMAND_DELETE, NULL);
+               g_object_unref (dom_selection);
+       } else
+               e_html_editor_view_exec_command (view, E_HTML_EDITOR_VIEW_COMMAND_DELETE, NULL);
 
        e_html_editor_view_force_spell_check_for_current_paragraph (view);
 }
@@ -12356,12 +12429,6 @@ e_html_editor_view_redo (EHTMLEditorView *view)
        view->priv->undo_redo_in_progress = FALSE;
 }
 
-static gboolean
-event_selection_was_collapsed (EHTMLEditorViewHistoryEvent *ev)
-{
-       return (ev->before.start.x == ev->before.end.x) && (ev->before.start.y == ev->before.end.y);
-}
-
 void
 e_html_editor_view_undo (EHTMLEditorView *view)
 {