[gtk/ebassi/new-a11y: 5/14] Add GtkAccessibleStateSet

[Emmanuele Bassi <ebassi src gnome org>]

commit 5bcfa473bce2b475cba08733220039ce1acc65b2
Author: Emmanuele Bassi <ebassi gnome org>
Date:   Wed Jul 8 16:45:57 2020 +0100

    Add GtkAccessibleStateSet
    
    Since states can be set or unset, we need a container type that has all
    the possible states, and a bitmask that tells us which ones are set.

 gtk/gtkaccessiblestateset.c        | 208 +++++++++++++++++++++++++++++++++++++
 gtk/gtkaccessiblestatesetprivate.h |  49 +++++++++
 gtk/meson.build                    |   1 +
 3 files changed, 258 insertions(+)
---
diff --git a/gtk/gtkaccessiblestateset.c b/gtk/gtkaccessiblestateset.c
new file mode 100644
index 0000000000..b494adf5cf
--- /dev/null
+++ b/gtk/gtkaccessiblestateset.c
@@ -0,0 +1,208 @@
+/* gtkaccessiblestateset.c: Accessible state
+ *
+ * Copyright 2020  GNOME Foundation
+ *
+ * SPDX-License-Identifier: LGPL-2.1-or-later
+ *
+ * This library is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU Lesser General Public
+ * License as published by the Free Software Foundation; either
+ * version 2.1 of the License, or (at your option) any later version.
+ *
+ * This library 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
+ * Lesser General Public License for more details.
+ *
+ * You should have received a copy of the GNU Lesser General Public
+ * License along with this library; if not, see <http://www.gnu.org/licenses/>.
+ */
+
+#include "config.h"
+
+#include "gtkaccessiblestatesetprivate.h"
+
+#include "gtkbitmaskprivate.h"
+#include "gtkenums.h"
+
+/* Keep in sync with GtkAccessibleState in gtkenums.h */
+#define LAST_STATE GTK_ACCESSIBLE_STATE_SELECTED
+
+struct _GtkAccessibleStateSet
+{
+  GtkBitmask *states_set;
+
+  GtkAccessibleValue **state_values;
+};
+
+static GtkAccessibleStateSet *
+gtk_accessible_state_set_init (GtkAccessibleStateSet *self)
+{
+  self->states_set = _gtk_bitmask_new ();
+  self->state_values = g_new (GtkAccessibleValue*, LAST_STATE);
+
+  /* Initialize all state values, so we can always get the full state */
+  for (int i = 0; i < LAST_STATE; i++)
+    self->state_values[i] = gtk_accessible_value_get_default_for_state (i);
+
+  return self;
+}
+
+GtkAccessibleStateSet *
+gtk_accessible_state_set_new (void)
+{
+  GtkAccessibleStateSet *set = g_rc_box_new0 (GtkAccessibleStateSet);
+
+  return gtk_accessible_state_set_init (set);
+}
+
+GtkAccessibleStateSet *
+gtk_accessible_state_set_ref (GtkAccessibleStateSet *self)
+{
+  g_return_val_if_fail (self != NULL, NULL);
+
+  return g_rc_box_acquire (self);
+}
+
+static void
+gtk_accessible_state_set_free (gpointer data)
+{
+  GtkAccessibleStateSet *self = data;
+
+  for (int i = 0; i < LAST_STATE; i++)
+    {
+      if (self->state_values[i] != NULL)
+        gtk_accessible_value_unref (self->state_values[i]);
+    }
+
+  g_free (self->state_values);
+
+  _gtk_bitmask_free (self->states_set);
+}
+
+void
+gtk_accessible_state_set_unref (GtkAccessibleStateSet *self)
+{
+  g_rc_box_release_full (self, gtk_accessible_state_set_free);
+}
+
+void
+gtk_accessible_state_set_add (GtkAccessibleStateSet *self,
+                              GtkAccessibleState     state,
+                              GtkAccessibleValue    *value)
+{
+  g_return_if_fail (state >= GTK_ACCESSIBLE_STATE_BUSY &&
+                    state <= GTK_ACCESSIBLE_STATE_SELECTED);
+
+  if (gtk_accessible_state_set_contains (self, state))
+    gtk_accessible_value_unref (self->state_values[state]);
+  else
+    self->states_set = _gtk_bitmask_set (self->states_set, state, TRUE);
+
+  self->state_values[state] = gtk_accessible_value_ref (value);
+}
+
+void
+gtk_accessible_state_set_remove (GtkAccessibleStateSet *self,
+                                 GtkAccessibleState     state)
+{
+  g_return_if_fail (state >= GTK_ACCESSIBLE_STATE_BUSY &&
+                    state <= GTK_ACCESSIBLE_STATE_SELECTED);
+
+  if (gtk_accessible_state_set_contains (self, state))
+    {
+      g_clear_pointer (&(self->state_values[state]), gtk_accessible_value_unref);
+      self->states_set = _gtk_bitmask_set (self->states_set, state, FALSE);
+    }
+}
+
+gboolean
+gtk_accessible_state_set_contains (GtkAccessibleStateSet *self,
+                                   GtkAccessibleState     state)
+{
+  g_return_val_if_fail (state >= GTK_ACCESSIBLE_STATE_BUSY &&
+                        state <= GTK_ACCESSIBLE_STATE_SELECTED,
+                        FALSE);
+
+  return _gtk_bitmask_get (self->states_set, state);
+}
+
+GtkAccessibleValue *
+gtk_accessible_state_set_get_value (GtkAccessibleStateSet *self,
+                                    GtkAccessibleState     state)
+{
+  g_return_val_if_fail (state >= GTK_ACCESSIBLE_STATE_BUSY &&
+                        state <= GTK_ACCESSIBLE_STATE_SELECTED,
+                        NULL);
+
+  return self->state_values[state];
+}
+
+static const char *state_names[] = {
+  [GTK_ACCESSIBLE_STATE_BUSY]     = "busy",
+  [GTK_ACCESSIBLE_STATE_CHECKED]  = "checked",
+  [GTK_ACCESSIBLE_STATE_DISABLED] = "disabled",
+  [GTK_ACCESSIBLE_STATE_EXPANDED] = "expanded",
+  [GTK_ACCESSIBLE_STATE_GRABBED]  = "grabbed",
+  [GTK_ACCESSIBLE_STATE_HIDDEN]   = "hidden",
+  [GTK_ACCESSIBLE_STATE_INVALID]  = "invalid",
+  [GTK_ACCESSIBLE_STATE_PRESSED]  = "pressed",
+  [GTK_ACCESSIBLE_STATE_SELECTED] = "selected",
+};
+
+/*< private >
+ * gtk_accessible_state_set_print:
+ * @self: a #GtkAccessibleStateSet
+ * @only_set: %TRUE if only the set states should be printed
+ * @buffer: a #GString
+ *
+ * Prints the contents of the #GtkAccessibleStateSet into @buffer.
+ */
+void
+gtk_accessible_state_set_print (GtkAccessibleStateSet *self,
+                                gboolean               only_set,
+                                GString               *buffer)
+{
+  if (only_set && _gtk_bitmask_is_empty (self->states_set))
+    {
+      g_string_append (buffer, "{}");
+      return;
+    }
+
+  g_string_append (buffer, "{\n");
+
+  for (int i = 0; i < G_N_ELEMENTS (state_names); i++)
+    {
+      if (only_set && !_gtk_bitmask_get (self->states_set, i))
+        continue;
+
+      g_string_append (buffer, "    ");
+      g_string_append (buffer, state_names[i]);
+      g_string_append (buffer, ": ");
+
+      gtk_accessible_value_print (self->state_values[i], buffer);
+
+      g_string_append (buffer, ",\n");
+    }
+
+  g_string_append (buffer, "}");
+}
+
+/*< private >
+ * gtk_accessible_state_set_to_string:
+ * @self: a #GtkAccessibleStateSet
+ *
+ * Prints the contents of a #GtkAccessibleStateSet into a string.
+ *
+ * Returns: (transfer full): a newly allocated string with the contents
+ *   of the #GtkAccessibleStateSet
+ */
+char *
+gtk_accessible_state_set_to_string (GtkAccessibleStateSet *self)
+{
+  GString *buf = g_string_new (NULL);
+
+  gtk_accessible_state_set_print (self, TRUE, buf);
+
+  return g_string_free (buf, FALSE);
+}
diff --git a/gtk/gtkaccessiblestatesetprivate.h b/gtk/gtkaccessiblestatesetprivate.h
new file mode 100644
index 0000000000..55d16aa7fd
--- /dev/null
+++ b/gtk/gtkaccessiblestatesetprivate.h
@@ -0,0 +1,49 @@
+/* gtkaccessiblestatesetprivate.h: Accessible state container
+ *
+ * Copyright 2020  GNOME Foundation
+ *
+ * SPDX-License-Identifier: LGPL-2.1-or-later
+ *
+ * This library is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU Lesser General Public
+ * License as published by the Free Software Foundation; either
+ * version 2.1 of the License, or (at your option) any later version.
+ *
+ * This library 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
+ * Lesser General Public License for more details.
+ *
+ * You should have received a copy of the GNU Lesser General Public
+ * License along with this library; if not, see <http://www.gnu.org/licenses/>.
+ */
+
+#pragma once
+
+#include "gtkaccessibleprivate.h"
+#include "gtkaccessiblevalueprivate.h"
+
+G_BEGIN_DECLS
+
+typedef struct _GtkAccessibleStateSet   GtkAccessibleStateSet;
+
+GtkAccessibleStateSet * gtk_accessible_state_set_new            (void);
+GtkAccessibleStateSet * gtk_accessible_state_set_ref            (GtkAccessibleStateSet *self);
+void                    gtk_accessible_state_set_unref          (GtkAccessibleStateSet *self);
+
+void                    gtk_accessible_state_set_add            (GtkAccessibleStateSet *self,
+                                                                 GtkAccessibleState     state,
+                                                                 GtkAccessibleValue    *value);
+void                    gtk_accessible_state_set_remove         (GtkAccessibleStateSet *self,
+                                                                 GtkAccessibleState     state);
+gboolean                gtk_accessible_state_set_contains       (GtkAccessibleStateSet *self,
+                                                                 GtkAccessibleState     state);
+GtkAccessibleValue *    gtk_accessible_state_set_get_value      (GtkAccessibleStateSet *self,
+                                                                 GtkAccessibleState     state);
+
+void                    gtk_accessible_state_set_print          (GtkAccessibleStateSet *self,
+                                                                 gboolean               only_set,
+                                                                 GString               *string);
+char *                  gtk_accessible_state_set_to_string      (GtkAccessibleStateSet *self);
+
+G_END_DECLS
diff --git a/gtk/meson.build b/gtk/meson.build
index 5ac04668cb..4a6cc3982b 100644
--- a/gtk/meson.build
+++ b/gtk/meson.build
@@ -16,6 +16,7 @@ gtk_private_sources = files([
   'fnmatch.c',
   'tools/gdkpixbufutils.c',
   'gsettings-mapping.c',
+  'gtkaccessiblestateset.c',
   'gtkaccessiblevalue.c',
   'gtkaccessiblevaluestatic.c',
   'gtkactionhelper.c',