ECompEditor: Add easy way to open URLs in the Location field

When the Location looks like a URL, let the user open the Location
in the default application for that scheme by showing a button
in the Location entry to open the URL.

Related to https://gitlab.gnome.org/GNOME/evolution/-/issues/1184

src/calendar/gui/e-comp-editor-property-parts.c

@@ -305,6 +305,45 @@ ecepp_location_save_list (GtkEntry *entry)
 	g_free (filename);
 }
 
+static gboolean
+ecepp_location_text_to_icon_visible (GBinding *binding,
+				     const GValue *source_value,
+				     GValue *target_value,
+				     gpointer user_data)
+{
+	const gchar *text;
+	gboolean icon_visible = FALSE;
+
+	text = g_value_get_string (source_value);
+
+	if (text && *text) {
+		struct _schemas {
+			const gchar *schema;
+			gint len;
+		} schemas[] = {
+			{ "http:", 5 },
+			{ "https:", 6 },
+			{ "www.", 4 },
+			{ "ftp:", 4 },
+			{ "sip:", 4 },
+			{ "tel:", 4 },
+			{ "xmpp:", 5 }
+		};
+		gint ii;
+
+		for (ii = 0; ii < G_N_ELEMENTS (schemas); ii++) {
+			if (g_ascii_strncasecmp (text, schemas[ii].schema, schemas[ii].len) == 0) {
+				icon_visible = TRUE;
+				break;
+			}
+		}
+	}
+
+	g_value_set_boolean (target_value, icon_visible);
+
+	return TRUE;
+}
+
 static void
 ecepp_location_create_widgets (ECompEditorPropertyPart *property_part,
 			       GtkWidget **out_label_widget,
@@ -338,6 +377,13 @@ ecepp_location_create_widgets (ECompEditorPropertyPart *property_part,
 	gtk_entry_set_completion (GTK_ENTRY (*out_edit_widget), completion);
 	g_object_unref (completion);
 
+	e_binding_bind_property_full (
+		*out_edit_widget, "text",
+		*out_edit_widget, "icon-visible",
+		G_BINDING_SYNC_CREATE,
+		ecepp_location_text_to_icon_visible,
+		NULL, NULL, NULL);
+
 	*out_label_widget = gtk_label_new_with_mnemonic (C_("ECompEditor", "_Location:"));
 	gtk_label_set_mnemonic_widget (GTK_LABEL (*out_label_widget), *out_edit_widget);
 
@@ -386,6 +432,7 @@ e_comp_editor_property_part_location_class_init (ECompEditorPropertyPartLocation
 	ECompEditorPropertyPartClass *part_class;
 
 	part_string_class = E_COMP_EDITOR_PROPERTY_PART_STRING_CLASS (klass);
+	part_string_class->entry_type = E_TYPE_URL_ENTRY;
 	part_string_class->prop_kind = I_CAL_LOCATION_PROPERTY;
 	part_string_class->i_cal_new_func = i_cal_property_new_location;
 	part_string_class->i_cal_set_func = i_cal_property_set_location;

src/e-util/e-url-entry.c

@@ -30,6 +30,11 @@
 
 #define ICON_POSITION GTK_ENTRY_ICON_SECONDARY
 
+enum {
+	PROP_0,
+	PROP_ICON_VISIBLE
+};
+
 G_DEFINE_TYPE (
 	EUrlEntry,
 	e_url_entry,
@@ -83,9 +88,60 @@ url_entry_icon_release_cb (GtkEntry *entry,
 	}
 }
 
+static void
+e_url_entry_set_property (GObject *object,
+			  guint property_id,
+			  const GValue *value,
+			  GParamSpec *pspec)
+{
+	switch (property_id) {
+		case PROP_ICON_VISIBLE:
+			e_url_entry_set_icon_visible (
+				E_URL_ENTRY (object),
+				g_value_get_boolean (value));
+			return;
+	}
+
+	G_OBJECT_WARN_INVALID_PROPERTY_ID (object, property_id, pspec);
+}
+
+static void
+e_url_entry_get_property (GObject *object,
+			  guint property_id,
+			  GValue *value,
+			  GParamSpec *pspec)
+{
+	switch (property_id) {
+		case PROP_ICON_VISIBLE:
+			g_value_set_boolean (
+				value,
+				e_url_entry_get_icon_visible (
+				E_URL_ENTRY (object)));
+			return;
+	}
+
+	G_OBJECT_WARN_INVALID_PROPERTY_ID (object, property_id, pspec);
+}
+
 static void
 e_url_entry_class_init (EUrlEntryClass *class)
 {
+	GObjectClass *object_class;
+
+	object_class = G_OBJECT_CLASS (class);
+	object_class->set_property = e_url_entry_set_property;
+	object_class->get_property = e_url_entry_get_property;
+
+	g_object_class_install_property (
+		object_class,
+		PROP_ICON_VISIBLE,
+		g_param_spec_boolean (
+			"icon-visible",
+			NULL,
+			NULL,
+			FALSE,
+			G_PARAM_READWRITE |
+			G_PARAM_STATIC_STRINGS));
 }
 
 static void
@@ -95,13 +151,10 @@ e_url_entry_init (EUrlEntry *url_entry)
 
 	entry = GTK_ENTRY (url_entry);
 
-	gtk_entry_set_icon_from_icon_name (
-		entry, ICON_POSITION, "go-jump");
-
 	gtk_entry_set_icon_tooltip_text (
 		entry, ICON_POSITION, _("Click here to open the URL"));
 
-	gtk_entry_set_placeholder_text (entry, _("Enter a URL here"));
+	e_url_entry_set_icon_visible (url_entry, TRUE);
 
 	/* XXX GtkEntryClass has no "icon_release" method pointer to
 	 *     override, so instead we have to connect to the signal. */
@@ -124,3 +177,29 @@ e_url_entry_new (void)
 	return g_object_new (E_TYPE_URL_ENTRY, NULL);
 }
 
+void
+e_url_entry_set_icon_visible (EUrlEntry *url_entry,
+			      gboolean visible)
+{
+	GtkEntry *entry;
+
+	g_return_if_fail (E_IS_URL_ENTRY (url_entry));
+
+	entry = GTK_ENTRY (url_entry);
+
+	if (visible) {
+		gtk_entry_set_icon_from_icon_name (entry, ICON_POSITION, "go-jump");
+		gtk_entry_set_placeholder_text (entry, _("Enter a URL here"));
+	} else {
+		gtk_entry_set_icon_from_icon_name (entry, ICON_POSITION, NULL);
+		gtk_entry_set_placeholder_text (entry, NULL);
+	}
+}
+
+gboolean
+e_url_entry_get_icon_visible (EUrlEntry *url_entry)
+{
+	g_return_val_if_fail (E_IS_URL_ENTRY (url_entry), FALSE);
+
+	return gtk_entry_get_icon_name (GTK_ENTRY (url_entry), ICON_POSITION) != NULL;
+}

src/e-util/e-url-entry.h

@@ -60,6 +60,9 @@ struct _EUrlEntryClass {
 
 GType		e_url_entry_get_type		(void) G_GNUC_CONST;
 GtkWidget *	e_url_entry_new			(void);
+void		e_url_entry_set_icon_visible	(EUrlEntry *url_entry,
+						 gboolean visible);
+gboolean	e_url_entry_get_icon_visible	(EUrlEntry *url_entry);
 
 G_END_DECLS