[evolution/wip/webkit2] Bug 758191 - Using Backspace within quotation header string can make cursor jump to very first posit

[Milan Crha <mcrha src gnome org>]

commit b2fc72b1a8b64a5250ab1ee448433fae5cb5ff4b
Author: Tomas Popela <tpopela redhat com>
Date:   Wed Mar 2 18:20:06 2016 +0100

    Bug 758191 - Using Backspace within quotation header string can make cursor jump to very first position

 .../composer/e-html-editor-view-dom-functions.c    |  233 +++++++++++++-------
 .../composer/e-html-editor-view-dom-functions.h    |    2 +-
 2 files changed, 157 insertions(+), 78 deletions(-)
---
diff --git a/web-extensions/composer/e-html-editor-view-dom-functions.c 
b/web-extensions/composer/e-html-editor-view-dom-functions.c
index c978419..9c8f5de 100644
--- a/web-extensions/composer/e-html-editor-view-dom-functions.c
+++ b/web-extensions/composer/e-html-editor-view-dom-functions.c
@@ -8545,11 +8545,153 @@ jump_to_next_table_cell (WebKitDOMDocument *document,
        return TRUE;
 }
 
+static gboolean
+delete_last_character_from_previous_line_in_quoted_block (WebKitDOMDocument *document,
+                                                         EHTMLEditorWebExtension *extension,
+                                                         guint key_val,
+                                                         guint state)
+{
+       EHTMLEditorHistoryEvent *ev = NULL;
+       gboolean hidden_space = FALSE;
+       WebKitDOMDocumentFragment *fragment;
+       WebKitDOMElement *element;
+       WebKitDOMNode *node, *beginning, *prev_sibling;
+
+       /* We have to be in quoted content. */
+       if (!dom_selection_is_citation (document))
+               return FALSE;
+
+       /* Selection is just caret. */
+       if (!dom_selection_is_collapsed (document))
+               return FALSE;
+
+       dom_selection_save (document);
+
+       element = webkit_dom_document_get_element_by_id (
+               document, "-x-evo-selection-start-marker");
+
+       /* Before the caret are just quote characters */
+       beginning = webkit_dom_node_get_previous_sibling (WEBKIT_DOM_NODE (element));
+       if (!(beginning && WEBKIT_DOM_IS_ELEMENT (beginning))) {
+               WebKitDOMNode *parent;
+
+               parent = webkit_dom_node_get_parent_node (WEBKIT_DOM_NODE (element));
+               if (WEBKIT_DOM_IS_HTML_ANCHOR_ELEMENT (parent))
+                       beginning = webkit_dom_node_get_previous_sibling (parent);
+               else
+                       goto out;
+       }
+
+       /* Before the text is the beginning of line. */
+       if (!(element_has_class (WEBKIT_DOM_ELEMENT (beginning), "-x-evo-quoted")))
+               goto out;
+
+       /* If we are just on the beginning of the line and not on the beginning of
+        * the block we need to remove the last character ourselves as well, otherwise
+        * WebKit will put the caret to wrong position. */
+       if (!(prev_sibling = webkit_dom_node_get_previous_sibling (beginning)))
+               goto out;
+
+       if (key_val != ~0) {
+               ev = g_new0 (EHTMLEditorHistoryEvent, 1);
+               ev->type = HISTORY_DELETE;
+
+               dom_selection_get_coordinates (
+                       document,
+                       &ev->before.start.x,
+                       &ev->before.start.y,
+                       &ev->before.end.x,
+                       &ev->before.end.y);
+
+               fragment = webkit_dom_document_create_document_fragment (document);
+       }
+
+       if (WEBKIT_DOM_IS_HTML_BR_ELEMENT (prev_sibling)) {
+               if (key_val != ~0)
+                       webkit_dom_node_append_child (WEBKIT_DOM_NODE (fragment), prev_sibling, NULL);
+               else
+                       remove_node (prev_sibling);
+       }
+
+       prev_sibling = webkit_dom_node_get_previous_sibling (beginning);
+       if (WEBKIT_DOM_IS_ELEMENT (prev_sibling) &&
+           webkit_dom_element_has_attribute (WEBKIT_DOM_ELEMENT (prev_sibling), "data-hidden-space")) {
+               hidden_space = TRUE;
+               if (key_val != ~0)
+                       webkit_dom_node_insert_before (
+                               WEBKIT_DOM_NODE (fragment),
+                               prev_sibling,
+                               webkit_dom_node_get_first_child (WEBKIT_DOM_NODE (fragment)),
+                               NULL);
+               else
+                       remove_node (prev_sibling);
+       }
+
+       node = webkit_dom_node_get_previous_sibling (beginning);
+
+       if (key_val != ~0)
+               webkit_dom_node_append_child (WEBKIT_DOM_NODE (fragment), beginning, NULL);
+       else
+               remove_node (beginning);
+
+       if (!hidden_space) {
+               if (key_val != ~0) {
+                       gchar *data;
+
+                       data = webkit_dom_character_data_substring_data (
+                               WEBKIT_DOM_CHARACTER_DATA (node),
+                               webkit_dom_character_data_get_length (
+                                       WEBKIT_DOM_CHARACTER_DATA (node)) -1,
+                               1,
+                               NULL);
+
+                       webkit_dom_node_append_child (
+                               WEBKIT_DOM_NODE (fragment),
+                               WEBKIT_DOM_NODE (
+                                       webkit_dom_document_create_text_node (document, data)),
+                               NULL);
+
+                       g_free (data);
+               }
+
+               webkit_dom_character_data_delete_data (
+                       WEBKIT_DOM_CHARACTER_DATA (node),
+                       webkit_dom_character_data_get_length (
+                               WEBKIT_DOM_CHARACTER_DATA (node)) -1,
+                       1,
+                       NULL);
+       }
+
+       if (key_val != ~0) {
+               EHTMLEditorUndoRedoManager *manager;
+
+               dom_selection_get_coordinates (
+                       document,
+                       &ev->after.start.x,
+                       &ev->after.start.y,
+                       &ev->after.end.x,
+                       &ev->after.end.y);
+
+               ev->data.fragment = fragment;
+
+               manager = e_html_editor_web_extension_get_undo_redo_manager (extension);
+               e_html_editor_undo_redo_manager_insert_history_event (manager, ev);
+       }
+
+       dom_selection_restore (document);
+
+       return TRUE;
+ out:
+       dom_selection_restore (document);
+
+       return FALSE;
+}
+
 gboolean
-dom_delete_character_from_quoted_line_start (WebKitDOMDocument *document,
-                                            EHTMLEditorWebExtension *extension,
-                                            guint key_val,
-                                            guint state)
+dom_delete_last_character_on_line_in_quoted_block (WebKitDOMDocument *document,
+                                                  EHTMLEditorWebExtension *extension,
+                                                  guint key_val,
+                                                  guint state)
 {
        gboolean success = FALSE;
        WebKitDOMElement *element;
@@ -8573,7 +8715,9 @@ dom_delete_character_from_quoted_line_start (WebKitDOMDocument *document,
 
        /* We have to be on the end of line. */
        next_sibling = webkit_dom_node_get_next_sibling (node);
-       if (next_sibling && (!WEBKIT_DOM_IS_HTML_BR_ELEMENT (next_sibling) || 
webkit_dom_node_get_next_sibling (next_sibling)))
+       if (next_sibling &&
+           (!WEBKIT_DOM_IS_HTML_BR_ELEMENT (next_sibling) ||
+            webkit_dom_node_get_next_sibling (next_sibling)))
                goto out;
 
        /* Before the caret is just text. */
@@ -8593,77 +8737,8 @@ dom_delete_character_from_quoted_line_start (WebKitDOMDocument *document,
        if (!(element_has_class (WEBKIT_DOM_ELEMENT (beginning), "-x-evo-quoted")))
                goto out;
 
-       /* If we are just on the beginning of the line and not on the beginning of
-        * the block we need to remove the last character ourselves as well, otherwise
-        * WebKit will put the caret to wrong position. */
-       if (webkit_dom_node_get_previous_sibling (beginning)) {
-               EHTMLEditorHistoryEvent *ev = NULL;
-               WebKitDOMDocumentFragment *fragment;
-               WebKitDOMNode *prev_sibling;
-
-               if (key_val != ~0) {
-                       ev = g_new0 (EHTMLEditorHistoryEvent, 1);
-                       ev->type = HISTORY_DELETE;
-
-                       dom_selection_get_coordinates (
-                               document,
-                               &ev->before.start.x,
-                               &ev->before.start.y,
-                               &ev->before.end.x,
-                               &ev->before.end.y);
-
-                       fragment = webkit_dom_document_create_document_fragment (document);
-               }
-
-               prev_sibling = webkit_dom_node_get_previous_sibling (beginning);
-               if (WEBKIT_DOM_IS_HTML_BR_ELEMENT (prev_sibling)) {
-                       if (key_val != ~0)
-                               webkit_dom_node_append_child (WEBKIT_DOM_NODE (fragment), prev_sibling, NULL);
-                       else
-                               remove_node (prev_sibling);
-               }
-
-               prev_sibling = webkit_dom_node_get_previous_sibling (beginning);
-               if (WEBKIT_DOM_IS_ELEMENT (prev_sibling) &&
-                   webkit_dom_element_has_attribute (WEBKIT_DOM_ELEMENT (prev_sibling), 
"data-hidden-space")) {
-                       if (key_val != ~0)
-                               webkit_dom_node_insert_before (
-                                       WEBKIT_DOM_NODE (fragment),
-                                       prev_sibling,
-                                       webkit_dom_node_get_first_child (WEBKIT_DOM_NODE (fragment)),
-                                       NULL);
-                       else
-                               remove_node (prev_sibling);
-               }
-
-               if (key_val != ~0)
-                       webkit_dom_node_append_child (WEBKIT_DOM_NODE (fragment), beginning, NULL);
-               else
-                       remove_node (beginning);
-
-               if (key_val != ~0) {
-                       EHTMLEditorUndoRedoManager *manager;
-
-                       webkit_dom_node_append_child (WEBKIT_DOM_NODE (fragment), node, NULL);
-
-                       dom_selection_get_coordinates (
-                               document,
-                               &ev->after.start.x,
-                               &ev->after.start.y,
-                               &ev->after.end.x,
-                               &ev->after.end.y);
-
-                       ev->data.fragment = fragment;
-
-                       manager = e_html_editor_web_extension_get_undo_redo_manager (extension);
-                       e_html_editor_undo_redo_manager_insert_history_event (manager, ev);
-               } else
-                       remove_node (node);
-
-               dom_selection_restore (document);
-
-               return TRUE;
-       }
+       if (!webkit_dom_node_get_previous_sibling (beginning))
+               goto out;
 
        if (key_val != ~0)
                save_history_for_delete_or_backspace (
@@ -9061,7 +9136,11 @@ key_press_event_process_delete_or_backspace_key (WebKitDOMDocument *document,
        }
 
        if (!local_delete && !html_mode &&
-           dom_delete_character_from_quoted_line_start (document, extension, key_val, state))
+           dom_delete_last_character_on_line_in_quoted_block (document, extension, key_val, state))
+               goto out;
+
+       if (!local_delete && !html_mode &&
+           delete_last_character_from_previous_line_in_quoted_block (document, extension, key_val, state))
                goto out;
 
        if (dom_fix_structure_after_delete_before_quoted_content (document, extension, key_val, state, FALSE))
diff --git a/web-extensions/composer/e-html-editor-view-dom-functions.h 
b/web-extensions/composer/e-html-editor-view-dom-functions.h
index 428feb3..f1e451a 100644
--- a/web-extensions/composer/e-html-editor-view-dom-functions.h
+++ b/web-extensions/composer/e-html-editor-view-dom-functions.h
@@ -162,7 +162,7 @@ void                dom_set_visited_link_color      (WebKitDOMDocument *document,
 gboolean       dom_change_quoted_block_to_normal
                                                (WebKitDOMDocument *document,
                                                 EHTMLEditorWebExtension *extension);
-gboolean       dom_delete_character_from_quoted_line_start
+gboolean       dom_delete_last_character_on_line_in_quoted_block
                                                (WebKitDOMDocument *document,
                                                 EHTMLEditorWebExtension *extension,
                                                 guint key_val,