[gtk/matthiasc/a11y: 7/7] wip: Begin implementing Text for labels

[Matthias Clasen <matthiasc src gnome org>]

commit af3b86e43d347c902089913477c6ee1d5f3cd44c
Author: Matthias Clasen <mclasen redhat com>
Date:   Fri Oct 9 23:35:00 2020 -0400

    wip: Begin implementing Text for labels
    
    This is just a bare-bones implementation of GetText,
    and a stubbed out GetAttributes. Just enough to make
    label text show up in accerciser.

 gtk/a11y/gtkatspicontext.c | 98 ++++++++++++++++++++++++++++++++++++++++++++++
 1 file changed, 98 insertions(+)
---
diff --git a/gtk/a11y/gtkatspicontext.c b/gtk/a11y/gtkatspicontext.c
index d932f06c2c..f531a2b288 100644
--- a/gtk/a11y/gtkatspicontext.c
+++ b/gtk/a11y/gtkatspicontext.c
@@ -421,6 +421,8 @@ handle_accessible_method (GDBusConnection       *connection,
       GVariantBuilder builder = G_VARIANT_BUILDER_INIT (G_VARIANT_TYPE ("as"));
 
       g_variant_builder_add (&builder, "s", "org.a11y.atspi.Accessible");
+      if (GTK_IS_LABEL (accessible))
+        g_variant_builder_add (&builder, "s", "org.a11y.atspi.Text");
       g_dbus_method_invocation_return_value (invocation, g_variant_new ("(as)", &builder));
     }
 
@@ -505,6 +507,91 @@ static const GDBusInterfaceVTable accessible_vtable = {
   NULL,
 };
 
+static void
+handle_text_method (GDBusConnection       *connection,
+                    const gchar           *sender,
+                    const gchar           *object_path,
+                    const gchar           *interface_name,
+                    const gchar           *method_name,
+                    GVariant              *parameters,
+                    GDBusMethodInvocation *invocation,
+                    gpointer               user_data)
+{
+  GtkAtSpiContext *self = user_data;
+  GtkAccessible *accessible = gtk_at_context_get_accessible (GTK_AT_CONTEXT (self));
+  GtkWidget *widget = GTK_WIDGET (accessible);
+
+  if (g_strcmp0 (method_name, "GetText") == 0)
+    {
+      int start, end;
+      const char *text;
+      const char *p, *q;
+      char *substring;
+
+      g_variant_get (parameters, "(ii)", &start, &end);
+
+      text = gtk_label_get_text (GTK_LABEL (widget));
+      p = g_utf8_offset_to_pointer (text, start);
+      q = g_utf8_offset_to_pointer (text, end);
+
+      substring = g_strndup (p, q - p);
+
+      g_dbus_method_invocation_return_value (invocation, g_variant_new ("(s)", substring));
+      g_free (substring);
+    }
+  else if (g_strcmp0 (method_name, "GetAttributes") == 0)
+    {
+      int offset;
+      GVariantBuilder builder = G_VARIANT_BUILDER_INIT (G_VARIANT_TYPE ("a{ss}"));
+      const char *text;
+      int len;
+
+      g_variant_get (parameters, "(i)", &offset);
+
+      text = gtk_label_get_text (GTK_LABEL (widget));
+      len = g_utf8_strlen (text, -1);
+
+      g_dbus_method_invocation_return_value (invocation, g_variant_new ("(a{ss}ii)", &builder, 0, len));
+    }
+}
+
+static GVariant *
+handle_text_get_property (GDBusConnection  *connection,
+                          const gchar      *sender,
+                          const gchar      *object_path,
+                          const gchar      *interface_name,
+                          const gchar      *property_name,
+                          GError          **error,
+                          gpointer          user_data)
+{
+  GtkAtSpiContext *self = user_data;
+  GtkAccessible *accessible = gtk_at_context_get_accessible (GTK_AT_CONTEXT (self));
+  GtkWidget *widget = GTK_WIDGET (accessible);
+
+  if (g_strcmp0 (property_name, "CharacterCount") == 0)
+    {
+      const char *text;
+      int len;
+
+      text = gtk_label_get_text (GTK_LABEL (widget));
+      len = g_utf8_strlen (text, -1);
+
+      return g_variant_new_int32 (len);
+    }
+  else if (g_strcmp0 (property_name, "CaretOffset") == 0)
+    {
+      return g_variant_new_int32 (0);
+    }
+
+  return NULL;
+}
+
+static const GDBusInterfaceVTable text_vtable = {
+  handle_text_method,
+  handle_text_get_property,
+  NULL,
+};
+
 static void
 gtk_at_spi_context_register_object (GtkAtSpiContext *self)
 {
@@ -515,6 +602,17 @@ gtk_at_spi_context_register_object (GtkAtSpiContext *self)
                                      self,
                                      NULL,
                                      NULL);
+
+  if (GTK_IS_LABEL (gtk_at_context_get_accessible (GTK_AT_CONTEXT (self))))
+    {
+      g_dbus_connection_register_object (self->connection,
+                                         self->context_path,
+                                         (GDBusInterfaceInfo *) &atspi_text_interface,
+                                         &text_vtable,
+                                         self,
+                                         NULL,
+                                         NULL);
+    }
 }
 
 static void