embed: Implement unsubmitted modified forms warning in WebKit2

Installing a web extension to access the DOM.

https://bugzilla.gnome.org/show_bug.cgi?id=684437

3 files changed, 215 insertions, 0 deletions

diff --git a/embed/web-extension/Makefile.am b/embed/web-extension/Makefile.am
new file mode 100644
index 000000000..fe7277288
--- /dev/null
+++ b/embed/web-extension/Makefile.am
@@ -0,0 +1,20 @@
+webextension_LTLIBRARIES = libephywebextension.la
+
+webextensiondir = \
+	$(libdir)/epiphany/$(EPIPHANY_MAJOR)/web-extensions
+
+libephywebextension_la_SOURCES = \
+	ephy-web-extension.c \
+	ephy-web-extension.h
+
+libephywebextension_la_CPPFLAG = \
+	$(AM_CPPFLAGS)
+
+libephywebextension_la_CFLAGS = \
+	$(WEB_EXTENSION_CFLAGS)
+
+libephywebextension_la_LIBADD = \
+	$(WEB_EXTENSION_LIBS)
+
+libephywebextension_la_LDFLAGS = \
+	-module -avoid-version -no-undefined
diff --git a/embed/web-extension/ephy-web-extension.c b/embed/web-extension/ephy-web-extension.c
new file mode 100644
index 000000000..1650026a3
--- /dev/null
+++ b/embed/web-extension/ephy-web-extension.c
@@ -0,0 +1,169 @@
+/* -*- Mode: C; tab-width: 2; indent-tabs-mode: nil; c-basic-offset: 2 -*- */
+/*
+ *  Copyright © 2012 Igalia S.L.
+ *
+ *  This program is free software; you can redistribute it and/or modify
+ *  it under the terms of the GNU General Public License as published by
+ *  the Free Software Foundation; either version 2, or (at your option)
+ *  any later version.
+ *
+ *  This program is distributed in the hope that it will be useful,
+ *  but WITHOUT ANY WARRANTY; without even the implied warranty of
+ *  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ *  GNU General Public License for more details.
+ *
+ *  You should have received a copy of the GNU General Public License
+ *  along with this program; if not, write to the Free Software
+ *  Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301, USA.
+ */
+
+#include "config.h"
+#include "ephy-web-extension.h"
+
+#include <gio/gio.h>
+#include <webkit2/webkit-web-extension.h>
+
+static const char introspection_xml[] =
+  "<node>"
+  " <interface name='org.gnome.Epiphany.WebExtension'>"
+  "  <method name='HasModifiedForms'>"
+  "   <arg type='t' name='page_id' direction='in'/>"
+  "   <arg type='b' name='has_modified_forms' direction='out'/>"
+  "  </method>"
+  " </interface>"
+  "</node>";
+
+#define MIN_INPUT_LENGTH 50
+
+static gboolean
+ephy_web_extension_page_has_modified_forms (WebKitWebPage *web_page)
+{
+  WebKitDOMHTMLCollection *forms = NULL;
+  WebKitDOMDocument *document = NULL;
+  gulong forms_n;
+  int i;
+
+  document = webkit_web_page_get_dom_document (web_page);
+  forms = webkit_dom_document_get_forms (document);
+  forms_n = webkit_dom_html_collection_get_length (forms);
+
+  for (i = 0; i < forms_n; i++) {
+    WebKitDOMHTMLCollection *elements;
+    WebKitDOMNode *form_element = webkit_dom_html_collection_item (forms, i);
+    gulong elements_n;
+    int j;
+    gboolean modified_input_element = FALSE;
+
+    elements = webkit_dom_html_form_element_get_elements (WEBKIT_DOM_HTML_FORM_ELEMENT (form_element));
+    elements_n = webkit_dom_html_collection_get_length (elements);
+
+    for (j = 0; j < elements_n; j++) {
+      WebKitDOMNode *element;
+
+      element = webkit_dom_html_collection_item (elements, j);
+
+      if (WEBKIT_DOM_IS_HTML_TEXT_AREA_ELEMENT (element))
+        if (webkit_dom_html_text_area_element_is_edited (WEBKIT_DOM_HTML_TEXT_AREA_ELEMENT (element)))
+          return TRUE;
+
+      if (WEBKIT_DOM_IS_HTML_INPUT_ELEMENT (element))
+        if (webkit_dom_html_input_element_is_edited (WEBKIT_DOM_HTML_INPUT_ELEMENT (element))) {
+          glong length;
+          char *text;
+
+          /* A small heuristic here. If there's only one input element
+           * modified and it does not have a lot of text the user is
+           * likely not very interested in saving this work, so do
+           * nothing (eg, google search input). */
+          if (modified_input_element)
+            return TRUE;
+
+          modified_input_element = TRUE;
+
+          text = webkit_dom_html_input_element_get_value (WEBKIT_DOM_HTML_INPUT_ELEMENT (element));
+          length = g_utf8_strlen (text, -1);
+          g_free (text);
+
+          if (length > MIN_INPUT_LENGTH)
+            return TRUE;
+        }
+    }
+  }
+
+  return FALSE;
+}
+
+static void
+handle_method_call (GDBusConnection *connection,
+                    const char *sender,
+                    const char *object_path,
+                    const char *interface_name,
+                    const char *method_name,
+                    GVariant *parameters,
+                    GDBusMethodInvocation *invocation,
+                    gpointer user_data)
+{
+  WebKitWebExtension *web_extension = WEBKIT_WEB_EXTENSION (user_data);
+  WebKitWebPage *web_page;
+  guint64 page_id;
+
+  if (g_strcmp0 (interface_name, EPHY_WEB_EXTENSION_INTERFACE) != 0)
+    return;
+
+  g_variant_get(parameters, "(t)", &page_id);
+  web_page = webkit_web_extension_get_page (web_extension, page_id);
+  if (!web_page) {
+    g_dbus_method_invocation_return_error (invocation, G_DBUS_ERROR, G_DBUS_ERROR_INVALID_ARGS,
+                                           "Invalid page ID: %"G_GUINT64_FORMAT, page_id);
+    return;
+  }
+
+  if (g_strcmp0 (method_name, "HasModifiedForms") == 0) {
+    gboolean has_modifed_forms;
+
+    has_modifed_forms = ephy_web_extension_page_has_modified_forms (web_page);
+    g_dbus_method_invocation_return_value (invocation, g_variant_new ("(b)", has_modifed_forms));
+  }
+}
+
+static const GDBusInterfaceVTable interface_vtable = {
+  handle_method_call,
+  NULL,
+  NULL
+};
+
+static void
+bus_acquired_cb (GDBusConnection *connection,
+                 const char *name,
+                 gpointer user_data)
+{
+  guint registration_id;
+  GError *error = NULL;
+  static GDBusNodeInfo *introspection_data = NULL;
+  if (!introspection_data)
+    introspection_data = g_dbus_node_info_new_for_xml (introspection_xml, NULL);
+
+  registration_id = g_dbus_connection_register_object (connection,
+                                                       EPHY_WEB_EXTENSION_OBJECT_PATH,
+                                                       introspection_data->interfaces[0],
+                                                       &interface_vtable,
+                                                       g_object_ref (user_data),
+                                                       (GDestroyNotify)g_object_unref,
+                                                       &error);
+  if (!registration_id) {
+    g_warning ("Failed to register object: %s\n", error->message);
+    g_error_free (error);
+  }
+}
+
+G_MODULE_EXPORT void
+webkit_web_extension_initialize (WebKitWebExtension *extension)
+{
+  g_bus_own_name (G_BUS_TYPE_SESSION,
+                  EPHY_WEB_EXTENSION_SERVICE_NAME,
+                  G_BUS_NAME_OWNER_FLAGS_NONE,
+                  bus_acquired_cb,
+                  NULL, NULL,
+                  g_object_ref (extension),
+                  (GDestroyNotify)g_object_unref);
+}
diff --git a/embed/web-extension/ephy-web-extension.h b/embed/web-extension/ephy-web-extension.h
new file mode 100644
index 000000000..7792480a5
--- /dev/null
+++ b/embed/web-extension/ephy-web-extension.h
@@ -0,0 +1,26 @@
+/*
+ *  Copyright © 2012 Igalia S.L.
+ *
+ *  This program is free software; you can redistribute it and/or modify
+ *  it under the terms of the GNU General Public License as published by
+ *  the Free Software Foundation; either version 2, or (at your option)
+ *  any later version.
+ *
+ *  This program is distributed in the hope that it will be useful,
+ *  but WITHOUT ANY WARRANTY; without even the implied warranty of
+ *  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ *  GNU General Public License for more details.
+ *
+ *  You should have received a copy of the GNU General Public License
+ *  along with this program; if not, write to the Free Software
+ *  Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301, USA.
+ */
+
+#ifndef EPHY_WEB_EXTENSION_H
+#define EPHY_WEB_EXTENSION_H
+
+#define EPHY_WEB_EXTENSION_SERVICE_NAME "org.gnome.Epiphany.WebExtension"
+#define EPHY_WEB_EXTENSION_OBJECT_PATH  "/org/gnome/Epiphany/WebExtension"
+#define EPHY_WEB_EXTENSION_INTERFACE    "org.gnome.Epiphany.WebExtension"
+
+#endif /* EPHY_WEB_EXTENSION_H */