[gtk+] inspector: Prepare TreeModelRenderNode for brave new world

[Benjamin Otte <otte src gnome org>]

commit d691dfc89402778179ddc6e2a7b7574792666d1f
Author: Benjamin Otte <otte redhat com>
Date:   Mon Dec 12 18:53:41 2016 +0100

    inspector: Prepare TreeModelRenderNode for brave new world
    
    I'm about to move children handling to the container node, which means
    the generic code can no longer assume children APIs existing.
    
    So rewrite the treemodel to work without it.

 gtk/inspector/gtktreemodelrendernode.c |  317 ++++++++++++++++++++++---------
 gtk/inspector/gtktreemodelrendernode.h |    3 -
 2 files changed, 225 insertions(+), 95 deletions(-)
---
diff --git a/gtk/inspector/gtktreemodelrendernode.c b/gtk/inspector/gtktreemodelrendernode.c
index 701f74b..9e5c8a9 100644
--- a/gtk/inspector/gtktreemodelrendernode.c
+++ b/gtk/inspector/gtktreemodelrendernode.c
@@ -19,6 +19,18 @@
 
 #include "gtktreemodelrendernode.h"
 
+typedef struct _TreeElement TreeElement;
+
+/* This is an array of all nodes and the index of their parent. When adding a node,
+ * we first add the node itself, and then all their children pointing the parent to
+ * this element.
+ */
+struct _TreeElement
+{
+  GskRenderNode *node;
+  int            parent;
+};
+
 struct _GtkTreeModelRenderNodePrivate
 {
   GtkTreeModelRenderNodeGetFunc  get_func;
@@ -26,6 +38,7 @@ struct _GtkTreeModelRenderNodePrivate
   GType                         *column_types;
 
   GskRenderNode                 *root;
+  GArray                        *nodes;
 };
 
 static void gtk_tree_model_render_node_tree_model_init  (GtkTreeModelIface   *iface);
@@ -35,27 +48,82 @@ G_DEFINE_TYPE_WITH_CODE (GtkTreeModelRenderNode, gtk_tree_model_render_node, G_T
                         G_IMPLEMENT_INTERFACE (GTK_TYPE_TREE_MODEL,
                                                gtk_tree_model_render_node_tree_model_init))
 
+static gint
+element_from_iter (GtkTreeModelRenderNode *model,
+                   GtkTreeIter            *iter)
+{
+  return GPOINTER_TO_INT (iter->user_data2);
+}
+
+static void
+iter_from_element (GtkTreeModelRenderNode *model,
+                   GtkTreeIter            *iter,
+                   gint                    elt)
+{
+  iter->user_data = model;
+  iter->user_data2 = GINT_TO_POINTER (elt);
+}
+
 static GskRenderNode *
-get_nth_child (GskRenderNode *node,
-               gint           i)
+node_from_element (GtkTreeModelRenderNode *model,
+                   gint                    elt)
 {
-  for (node = gsk_render_node_get_first_child (node);
-       node != NULL && i > 0;
-       node = gsk_render_node_get_next_sibling (node))
-    i--;
+  return g_array_index (model->priv->nodes, TreeElement, elt).node;
+}
 
-  return node;
+static gint
+parent_element (GArray *nodes,
+        gint    idx)
+{
+  return g_array_index (nodes, TreeElement, idx).parent;
 }
 
-static int
-get_node_index (GskRenderNode *node)
+static gint
+get_nth_child (GArray *nodes,
+               gint    elt,
+               gint    nth)
 {
-  int result = 0;
+  guint i, count;
 
-  while ((node = gsk_render_node_get_previous_sibling (node)))
-    result++;
+  count = 0;
+  for (i = elt + 1; i < nodes->len; i++)
+    {
+      gint parent = parent_element (nodes, i);
 
-  return result;
+      if (parent < elt)
+        return FALSE;
+
+      if (parent != elt)
+        continue;
+
+      if (count == nth)
+        return i;
+
+      count++;
+    }
+
+  return -1;
+}
+
+static gint
+get_node_index (GArray *nodes,
+                gint    elt)
+{
+  gint parent, i, idx;
+
+  if (elt == 0)
+    return 0;
+
+  parent = parent_element (nodes, elt);
+  idx = 0;
+
+  for (i = elt; i > parent; i--)
+    {
+      if (parent_element (nodes, i) == parent)
+        idx++;
+    }
+
+  return idx;
 }
 
 static GtkTreeModelFlags
@@ -92,9 +160,9 @@ gtk_tree_model_render_node_get_iter (GtkTreeModel *tree_model,
 {
   GtkTreeModelRenderNode *nodemodel = GTK_TREE_MODEL_RENDER_NODE (tree_model);
   GtkTreeModelRenderNodePrivate *priv = nodemodel->priv;
-  GskRenderNode *node;
   int *indices;
   int depth, i;
+  int elt;
 
   if (priv->root == NULL)
     return FALSE;
@@ -105,15 +173,15 @@ gtk_tree_model_render_node_get_iter (GtkTreeModel *tree_model,
   if (depth < 1 || indices[0] != 0)
     return FALSE;
 
-  node = priv->root;
+  elt = 0;
   for (i = 1; i < depth; i++)
     {
-      node = get_nth_child (node, indices[i]);
-      if (node == NULL)
+      elt = get_nth_child (priv->nodes, elt, indices[i]);
+      if (elt < 0)
         return FALSE;
     }
 
-  gtk_tree_model_render_node_get_iter_from_node (nodemodel, iter, node);
+  iter_from_element (nodemodel, iter, elt);
   return TRUE;
 }
 
@@ -123,18 +191,16 @@ gtk_tree_model_render_node_get_path (GtkTreeModel *tree_model,
 {
   GtkTreeModelRenderNode *nodemodel = GTK_TREE_MODEL_RENDER_NODE (tree_model);
   GtkTreeModelRenderNodePrivate *priv = nodemodel->priv;
-  GskRenderNode *node;
   GtkTreePath *path;
+  gint elt;
 
   g_return_val_if_fail (priv->root != NULL, NULL);
 
   path = gtk_tree_path_new ();
-  node = gtk_tree_model_render_node_get_node_from_iter (nodemodel, iter);
 
-  while (node != priv->root)
+  for (elt = element_from_iter (nodemodel, iter); elt >= 0; elt = parent_element (priv->nodes, elt))
     {
-      gtk_tree_path_prepend_index (path, get_node_index (node));
-      node = gsk_render_node_get_parent (node);
+      gtk_tree_path_prepend_index (path, get_node_index (priv->nodes, elt));
     }
 
   gtk_tree_path_prepend_index (path, 0);
@@ -153,7 +219,7 @@ gtk_tree_model_render_node_get_value (GtkTreeModel *tree_model,
 
   g_value_init (value, priv->column_types[column]);
   priv->get_func (nodemodel,
-                  gtk_tree_model_render_node_get_node_from_iter (nodemodel, iter),
+                  node_from_element (nodemodel, element_from_iter (nodemodel, iter)),
                   column,
                   value);
 }
@@ -164,18 +230,27 @@ gtk_tree_model_render_node_iter_next (GtkTreeModel *tree_model,
 {
   GtkTreeModelRenderNode *nodemodel = GTK_TREE_MODEL_RENDER_NODE (tree_model);
   GtkTreeModelRenderNodePrivate *priv = nodemodel->priv;
-  GskRenderNode *node;
+  gint i, parent;
 
-  node = gtk_tree_model_render_node_get_node_from_iter (nodemodel, iter);
-  if (node == priv->root)
-    return FALSE;
-  
-  node = gsk_render_node_get_next_sibling (node);
-  if (node == NULL)
+  i = element_from_iter (nodemodel, iter);
+  parent = parent_element (priv->nodes, i);
+
+  if (parent < 0)
     return FALSE;
 
-  gtk_tree_model_render_node_get_iter_from_node (nodemodel, iter, node);
-  return TRUE;
+  for (i = i + 1; i < priv->nodes->len; i++)
+    {
+      if (parent_element (priv->nodes, i) < parent)
+        return FALSE;
+
+      if (parent_element (priv->nodes, i) == parent)
+        {
+          iter_from_element (nodemodel, iter, i);
+          return TRUE;
+        }
+    }
+
+  return FALSE;
 }
 
 static gboolean
@@ -184,18 +259,24 @@ gtk_tree_model_render_node_iter_previous (GtkTreeModel  *tree_model,
 {
   GtkTreeModelRenderNode *nodemodel = GTK_TREE_MODEL_RENDER_NODE (tree_model);
   GtkTreeModelRenderNodePrivate *priv = nodemodel->priv;
-  GskRenderNode *node;
+  gint i, parent;
 
-  node = gtk_tree_model_render_node_get_node_from_iter (nodemodel, iter);
-  if (node == priv->root)
-    return FALSE;
-  
-  node = gsk_render_node_get_previous_sibling (node);
-  if (node == NULL)
+  i = element_from_iter (nodemodel, iter);
+  parent = parent_element (priv->nodes, i);
+
+  if (parent < 0)
     return FALSE;
 
-  gtk_tree_model_render_node_get_iter_from_node (nodemodel, iter, node);
-  return TRUE;
+  for (i = i - 1; i > parent; i--)
+    {
+      if (parent_element (priv->nodes, i) == parent)
+        {
+          iter_from_element (nodemodel, iter, i);
+          return TRUE;
+        }
+    }
+
+  return FALSE;
 }
 
 static gboolean
@@ -205,22 +286,27 @@ gtk_tree_model_render_node_iter_children (GtkTreeModel *tree_model,
 {
   GtkTreeModelRenderNode *nodemodel = GTK_TREE_MODEL_RENDER_NODE (tree_model);
   GtkTreeModelRenderNodePrivate *priv = nodemodel->priv;
-  GskRenderNode *node;
+  gint elt;
 
   if (parent == NULL)
     {
-      node = priv->root;
+      if (!priv->root)
+        return FALSE;
+
+      iter_from_element (nodemodel, iter, 0);
+      return TRUE;
     }
   else
     {
-      node = gtk_tree_model_render_node_get_node_from_iter (nodemodel, parent);
-      node = gsk_render_node_get_first_child (node);
-    }
-  if (node == NULL)
-    return FALSE;
+      elt = element_from_iter (nodemodel, parent);
+      if (elt + 1 >= priv->nodes->len)
+        return FALSE;
+      if (parent_element (priv->nodes, elt + 1) != elt)
+        return FALSE;
 
-  gtk_tree_model_render_node_get_iter_from_node (nodemodel, iter, node);
-  return TRUE;
+      iter_from_element (nodemodel, iter, elt + 1);
+      return TRUE;
+    }
 }
 
 static gboolean
@@ -228,11 +314,16 @@ gtk_tree_model_render_node_iter_has_child (GtkTreeModel *tree_model,
                                           GtkTreeIter  *iter)
 {
   GtkTreeModelRenderNode *nodemodel = GTK_TREE_MODEL_RENDER_NODE (tree_model);
-  GskRenderNode *node;
+  GtkTreeModelRenderNodePrivate *priv = nodemodel->priv;
+  gint elt;
 
-  node = gtk_tree_model_render_node_get_node_from_iter (nodemodel, iter);
+  elt = element_from_iter (nodemodel, iter);
+  if (elt + 1 >= priv->nodes->len)
+    return FALSE;
+  if (parent_element (priv->nodes, elt + 1) != elt)
+    return FALSE;
 
-  return gsk_render_node_get_first_child (node) != NULL;
+  return TRUE;
 }
 
 static gint
@@ -241,18 +332,26 @@ gtk_tree_model_render_node_iter_n_children (GtkTreeModel *tree_model,
 {
   GtkTreeModelRenderNode *nodemodel = GTK_TREE_MODEL_RENDER_NODE (tree_model);
   GtkTreeModelRenderNodePrivate *priv = nodemodel->priv;
-  GskRenderNode *node;
+  gint elt, i, count;
 
   if (iter == NULL)
     return priv->root ? 1 : 0;
 
-  node = gtk_tree_model_render_node_get_node_from_iter (nodemodel, iter);
+  elt = element_from_iter (nodemodel, iter);
+  count = 0;
 
-  node = gsk_render_node_get_last_child (node);
-  if (node == NULL)
-    return 0;
+  for (i = elt + 1; i < priv->nodes->len; i++)
+    {
+      int parent = parent_element (priv->nodes, i);
+
+      if (parent < elt)
+        break;
 
-  return get_node_index (node) + 1;
+      if (parent == elt)
+        count++;
+    }
+
+  return count;
 }
 
 static gboolean
@@ -263,26 +362,28 @@ gtk_tree_model_render_node_iter_nth_child (GtkTreeModel *tree_model,
 {
   GtkTreeModelRenderNode *nodemodel = GTK_TREE_MODEL_RENDER_NODE (tree_model);
   GtkTreeModelRenderNodePrivate *priv = nodemodel->priv;
-  GskRenderNode *node;
+  gint elt;
 
   if (parent == NULL)
     {
       if (n > 0)
         return FALSE;
       
-      node = priv->root;
+      iter_from_element (nodemodel, iter, 0);
+      return TRUE;
     }
   else
     {
-      node = gtk_tree_model_render_node_get_node_from_iter (nodemodel, parent);
-      node = get_nth_child (node, n);
-    }
+      gint nth;
 
-  if (node == NULL)
-    return FALSE;
-  
-  gtk_tree_model_render_node_get_iter_from_node (nodemodel, iter, node);
-  return TRUE;
+      elt = element_from_iter (nodemodel, parent);
+      nth = get_nth_child (priv->nodes, elt, n);
+      if (nth < 0)
+        return FALSE;
+
+      iter_from_element (nodemodel, iter, nth);
+      return TRUE;
+    }
 }
 
 static gboolean
@@ -292,15 +393,15 @@ gtk_tree_model_render_node_iter_parent (GtkTreeModel *tree_model,
 {
   GtkTreeModelRenderNode *nodemodel = GTK_TREE_MODEL_RENDER_NODE (tree_model);
   GtkTreeModelRenderNodePrivate *priv = nodemodel->priv;
-  GskRenderNode *node;
+  gint elt, parent;
 
-  node = gtk_tree_model_render_node_get_node_from_iter (nodemodel, child);
-  if (node == priv->root)
-    return FALSE;
+  elt = element_from_iter (nodemodel, child);
+  parent = parent_element (priv->nodes, elt);
 
-  node = gsk_render_node_get_parent (node);
+  if (parent < 0)
+    return FALSE;
 
-  gtk_tree_model_render_node_get_iter_from_node (nodemodel, iter, node);
+  iter_from_element (nodemodel, iter, parent);
   return TRUE;
 }
 
@@ -329,6 +430,7 @@ gtk_tree_model_render_node_finalize (GObject *object)
   GtkTreeModelRenderNodePrivate *priv = model->priv;
 
   g_clear_pointer (&priv->root, gsk_render_node_unref);
+  g_clear_pointer (&priv->nodes, g_array_unref);
 
   G_OBJECT_CLASS (gtk_tree_model_render_node_parent_class)->finalize (object);
 }
@@ -345,11 +447,13 @@ static void
 gtk_tree_model_render_node_init (GtkTreeModelRenderNode *nodemodel)
 {
   nodemodel->priv = gtk_tree_model_render_node_get_instance_private (nodemodel);
+
+  nodemodel->priv->nodes = g_array_new (FALSE, FALSE, sizeof (TreeElement));
 }
 
 GtkTreeModel *
 gtk_tree_model_render_node_new (GtkTreeModelRenderNodeGetFunc get_func,
-                                gint                       n_columns,
+                                gint                          n_columns,
                                 ...)
 {
   GtkTreeModel *result;
@@ -399,6 +503,45 @@ gtk_tree_model_render_node_newv (GtkTreeModelRenderNodeGetFunc  get_func,
   return GTK_TREE_MODEL (result);
 }
 
+static void
+append_node (GtkTreeModelRenderNode *nodemodel,
+             GskRenderNode          *node,
+             int                     parent_index)
+{
+  GtkTreeModelRenderNodePrivate *priv = nodemodel->priv;
+  TreeElement element = { node, parent_index };
+
+  g_array_append_val (priv->nodes, element);
+
+  switch (gsk_render_node_get_node_type (node))
+    {
+    default:
+    case GSK_NOT_A_RENDER_NODE:
+      g_assert_not_reached ();
+      break;
+
+    case GSK_CAIRO_NODE:
+    case GSK_TEXTURE_NODE:
+      /* no children */
+      break;
+
+    case GSK_CONTAINER_NODE:
+      {
+        GskRenderNode *child;
+        gint elt_index;
+
+        elt_index = priv->nodes->len - 1;
+        for (child = gsk_render_node_get_first_child (node);
+             child;
+             child = gsk_render_node_get_next_sibling (child))
+          {
+            append_node (nodemodel, child, elt_index);
+          }
+      }
+      break;
+    }
+}
+
 void
 gtk_tree_model_render_node_set_root_node (GtkTreeModelRenderNode *model,
                                           GskRenderNode          *node)
@@ -421,6 +564,7 @@ gtk_tree_model_render_node_set_root_node (GtkTreeModelRenderNode *model,
       gtk_tree_path_free (path);
 
       gsk_render_node_unref (priv->root);
+      g_array_set_size (priv->nodes, 0);
     }
 
   priv->root = node;
@@ -430,8 +574,9 @@ gtk_tree_model_render_node_set_root_node (GtkTreeModelRenderNode *model,
       GtkTreeIter iter;
 
       gsk_render_node_ref (node);
+      append_node (model, node, -1);
 
-      gtk_tree_model_render_node_get_iter_from_node (model, &iter, node);
+      iter_from_element (model, &iter, 0);
       path = gtk_tree_path_new_first ();
       gtk_tree_model_row_inserted (GTK_TREE_MODEL (model), path, &iter);
       if (gsk_render_node_get_first_child (node))
@@ -455,20 +600,8 @@ gtk_tree_model_render_node_get_node_from_iter (GtkTreeModelRenderNode *model,
   g_return_val_if_fail (GTK_IS_TREE_MODEL_RENDER_NODE (model), NULL);
   g_return_val_if_fail (iter != NULL, NULL);
   g_return_val_if_fail (iter->user_data == model, NULL);
-  g_return_val_if_fail (GSK_IS_RENDER_NODE (iter->user_data2), NULL);
+  g_return_val_if_fail (GPOINTER_TO_INT (iter->user_data2) < model->priv->nodes->len, NULL);
 
-  return iter->user_data2;
+  return node_from_element (model, element_from_iter (model, iter));
 }
 
-void
-gtk_tree_model_render_node_get_iter_from_node (GtkTreeModelRenderNode *model,
-                                               GtkTreeIter            *iter,
-                                               GskRenderNode          *node)
-{
-  g_return_if_fail (GTK_IS_TREE_MODEL_RENDER_NODE (model));
-  g_return_if_fail (iter != NULL);
-  g_return_if_fail (GSK_IS_RENDER_NODE (node));
-
-  iter->user_data = model;
-  iter->user_data2 = node;
-}
diff --git a/gtk/inspector/gtktreemodelrendernode.h b/gtk/inspector/gtktreemodelrendernode.h
index a0f448a..5c28e44 100644
--- a/gtk/inspector/gtktreemodelrendernode.h
+++ b/gtk/inspector/gtktreemodelrendernode.h
@@ -69,9 +69,6 @@ void          gtk_tree_model_render_node_set_root_node          (GtkTreeModelRen
 GskRenderNode*gtk_tree_model_render_node_get_root_node          (GtkTreeModelRenderNode *model);
 GskRenderNode*gtk_tree_model_render_node_get_node_from_iter     (GtkTreeModelRenderNode *model,
                                                                  GtkTreeIter            *iter);
-void          gtk_tree_model_render_node_get_iter_from_node     (GtkTreeModelRenderNode *model,
-                                                                 GtkTreeIter            *iter,
-                                                                 GskRenderNode          *node);
 
 
 G_END_DECLS