[evolution/wip/webkit-composer: 100/372] Implement word-wrap

[Tomas Popela <tpopela src gnome org>]

commit 00c8efa2fcaa52a0d1ef2388b750c6e197690ebf
Author: Dan Vrátil <dvratil redhat com>
Date:   Fri Aug 10 14:23:38 2012 +0200

    Implement word-wrap

 e-util/e-editor-actions.c   |    5 +-
 e-util/e-editor-selection.c |  170 +++++++++++++++++++++++++++++++++++++++++++
 e-util/e-editor-selection.h |    1 +
 3 files changed, 172 insertions(+), 4 deletions(-)
---
diff --git a/e-util/e-editor-actions.c b/e-util/e-editor-actions.c
index 6627c19..93af22d 100644
--- a/e-util/e-editor-actions.c
+++ b/e-util/e-editor-actions.c
@@ -1057,10 +1057,7 @@ static void
 action_wrap_lines_cb (GtkAction *action,
                       EEditor *editor)
 {
-       /* FIXME WEBKIT */
-       /*
-       e_editor_widget_wrap_lines (editor);
-       */
+       e_editor_selection_wrap_lines (editor->priv->selection);
 }
 
 /*****************************************************************************
diff --git a/e-util/e-editor-selection.c b/e-util/e-editor-selection.c
index e592ed8..f1818a2 100644
--- a/e-util/e-editor-selection.c
+++ b/e-util/e-editor-selection.c
@@ -30,11 +30,14 @@
 #include <webkit/webkitdom.h>
 #include <string.h>
 #include <stdlib.h>
+#include <ctype.h>
 
 #define E_EDITOR_SELECTION_GET_PRIVATE(obj) \
        (G_TYPE_INSTANCE_GET_PRIVATE \
        ((obj), E_TYPE_EDITOR_SELECTION, EEditorSelectionPrivate))
 
+#define WORD_WRAP_LENGTH 71
+
 
 struct _EEditorSelectionPrivate {
 
@@ -1310,3 +1313,170 @@ e_editor_selection_insert_image (EEditorSelection *selection,
        webkit_dom_document_exec_command (
                        document, "insertImage", FALSE, image_uri);
 }
+
+static gint
+find_where_to_break_line (WebKitDOMNode *node,
+                         gint max_len)
+{
+       gchar *str, *text_start;
+       gunichar uc;
+       gint pos, last_space;
+
+       text_start = webkit_dom_text_get_whole_text ((WebKitDOMText *) node);
+
+       pos = 0;
+       last_space = 0;
+       str = text_start;
+       do {
+               uc = g_utf8_get_char (str);
+               if (!uc) {
+                       g_free (text_start);
+                       if (pos <= max_len) {
+                               return pos;
+                       } else {
+                               return last_space;
+                       }
+               }
+
+               /* If last_space is zero then the word is longer than
+                * WORD_WRAP_LENGTH characters, so continue untill we find
+                * a space */
+               if ((pos > max_len) && (last_space > 0)) {
+                       g_free (text_start);
+                       return last_space;
+               }
+
+               if (g_unichar_isspace (uc)) {
+                       last_space = pos;
+               }
+
+               pos += 1;
+               str = g_utf8_next_char (str);
+       } while (*str);
+
+       g_free (text_start);
+       return max_len;
+}
+
+void
+e_editor_selection_wrap_lines (EEditorSelection *selection)
+{
+       WebKitDOMRange *range;
+       WebKitDOMNode *node, *start_node;
+       WebKitDOMDocument *document;
+       WebKitDOMElement *element;
+       WebKitDOMDocumentFragment *fragment;
+       gint len;
+       gchar *html;
+
+       g_return_if_fail (E_IS_EDITOR_SELECTION (selection));
+
+       document = webkit_web_view_get_dom_document (selection->priv->webview);
+       range = editor_selection_get_current_range (selection);
+
+       /* Extend the range to include entire nodes */
+       webkit_dom_range_select_node_contents (
+               range,
+               webkit_dom_range_get_common_ancestor_container (range, NULL),
+               NULL);
+
+       /* Copy the selection from DOM, wrap the lines and then paste it back
+        * using the DOM command which will overwrite the selection, and
+        * record it as an undoable action */
+       fragment = webkit_dom_range_clone_contents (range, NULL);
+       node = WEBKIT_DOM_NODE (fragment);
+
+       start_node = node;
+       len = 0;
+       while (node) {
+               /* Find nearest text node */
+               if (webkit_dom_node_get_node_type (node) != 3) {
+                       if (webkit_dom_node_has_child_nodes (node)) {
+                               node = webkit_dom_node_get_first_child (node);
+                       } else if (webkit_dom_node_get_next_sibling (node)) {
+                               node = webkit_dom_node_get_next_sibling (node);
+                       } else {
+                               if (webkit_dom_node_is_equal_node (node, start_node)) {
+                                       break;
+                               }
+
+                               node = webkit_dom_node_get_parent_node (node);
+                               if (node) {
+                                       node = webkit_dom_node_get_next_sibling (node);
+                               }
+                       }
+                       continue;
+               }
+
+               /* If length of this node + what we already have is still less
+                * then 71 characters, then just join it and continue to next
+                * node */
+               if ((webkit_dom_character_data_get_length (
+                       (WebKitDOMCharacterData *) node) + len) < WORD_WRAP_LENGTH) {
+
+                       len += webkit_dom_character_data_get_length (
+                               (WebKitDOMCharacterData *) node);
+
+               } else {
+                       gint offset;
+
+                       /* Find where we can line-break the node so that it
+                        * effectively fills the rest of current row */
+                       offset = find_where_to_break_line (node, WORD_WRAP_LENGTH - len);
+
+                       if (offset > 0) {
+                               /* Split the node and append <BR> tag to it */
+                               webkit_dom_text_split_text (
+                                       (WebKitDOMText *) node, len + offset, NULL);
+
+                               element = webkit_dom_document_create_element (
+                                               document, "BR", NULL);
+
+                               /* WebKit throws warning when ref_child is NULL */
+                               if (webkit_dom_node_get_next_sibling (node)) {
+                                       webkit_dom_node_insert_before (
+                                               webkit_dom_node_get_parent_node (node),
+                                               WEBKIT_DOM_NODE (element),
+                                               webkit_dom_node_get_next_sibling (node),
+                                               NULL);
+                               } else {
+                                       webkit_dom_node_append_child (
+                                               webkit_dom_node_get_parent_node (node),
+                                               WEBKIT_DOM_NODE (element),
+                                               NULL);
+                               }
+
+                               len = 0;
+                       }
+               }
+
+               /* Skip to next node */
+               if (webkit_dom_node_get_next_sibling (node)) {
+                       node = webkit_dom_node_get_next_sibling (node);
+               } else {
+                       if (webkit_dom_node_is_equal_node (node, start_node)) {
+                               break;
+                       }
+
+                       node = webkit_dom_node_get_parent_node (node);
+                       if (node) {
+                               node = webkit_dom_node_get_next_sibling (node);
+                       }
+               }
+       }
+
+       /* Create a wrapper DIV and put the processed content into it */
+       element = webkit_dom_document_create_element (document, "DIV", NULL);
+       webkit_dom_node_append_child (
+               WEBKIT_DOM_NODE (element), WEBKIT_DOM_NODE (start_node), NULL);
+
+       /* Get HTML code of the processed content */
+       html = webkit_dom_html_element_get_inner_html (
+                       WEBKIT_DOM_HTML_ELEMENT (element));
+
+       /* Overwrite the current selection be the processed content, so that
+        * "UNDO" and "REDO" buttons work as expected */
+       e_editor_selection_insert_html (selection, html);
+
+       g_free (html);
+}
\ No newline at end of file
diff --git a/e-util/e-editor-selection.h b/e-util/e-editor-selection.h
index a444f5f..9ee9ad5 100644
--- a/e-util/e-editor-selection.h
+++ b/e-util/e-editor-selection.h
@@ -196,6 +196,7 @@ void                        e_editor_selection_insert_image (EEditorSelection *selection,
                                                         const gchar *image_uri);
 void                   e_editor_selection_insert_text  (EEditorSelection *selection,
                                                         const gchar *plain_text);
+void                   e_editor_selection_wrap_lines   (EEditorSelection *selection);
 
 G_END_DECLS