#include <gtk/gtk.h>

#include "owltreemodelslice.h"

struct _OwlTreeModelSlicePrivate {
  GtkTreeModel *child_model;
  GtkTreePath *root;
};

#define OWL_TREE_MODEL_SLICE_GET_PRIVATE(obj)  (G_TYPE_INSTANCE_GET_PRIVATE ((obj), OWL_TYPE_TREE_MODEL_SLICE, OwlTreeModelSlicePrivate))

static void owl_tree_model_slice_tree_model_init (GtkTreeModelIface *iface);

/*
 * Implementation prototypes
 */

static GtkTreeModelFlags owl_tree_model_slice_get_flags (GtkTreeModel *model);
static gint owl_tree_model_slice_get_n_columns (GtkTreeModel *model);
static GType owl_tree_model_slice_get_column_type (GtkTreeModel *model, gint index);
static gboolean owl_tree_model_slice_get_iter (GtkTreeModel *model, GtkTreeIter *iter, GtkTreePath *path);
// TODO get_path
static void owl_tree_model_slice_get_value (GtkTreeModel *model, GtkTreeIter *iter, gint column, GValue *value);
static gboolean owl_tree_model_slice_iter_next (GtkTreeModel *model, GtkTreeIter *iter);
static gboolean owl_tree_model_slice_iter_children (GtkTreeModel *model, GtkTreeIter *iter, GtkTreeIter *parent);
static gboolean owl_tree_model_slice_iter_has_child (GtkTreeModel *model, GtkTreeIter *iter);
static gint owl_tree_model_slice_iter_n_children  (GtkTreeModel *model, GtkTreeIter *iter);
static gboolean owl_tree_model_slice_iter_nth_child (GtkTreeModel *model, GtkTreeIter *iter, GtkTreeIter *parent, gint n);
static gboolean owl_tree_model_slice_iter_parent (GtkTreeModel *model, GtkTreeIter *iter, GtkTreeIter *child);
static void owl_tree_model_slice_ref_node (GtkTreeModel *model, GtkTreeIter *iter);
static void owl_tree_model_slice_unref_node (GtkTreeModel *model, GtkTreeIter *iter);

G_DEFINE_TYPE_EXTENDED (OwlTreeModelSlice,
                        owl_tree_model_slice,
                        G_TYPE_OBJECT,
                        0, 
                        G_IMPLEMENT_INTERFACE (GTK_TYPE_TREE_MODEL,
                                               owl_tree_model_slice_tree_model_init));

static void
owl_tree_model_slice_init (OwlTreeModelSlice *slice)
{
  slice->priv = OWL_TREE_MODEL_SLICE_GET_PRIVATE (slice);
}

static void
owl_tree_model_slice_class_init (OwlTreeModelSliceClass *klass)
{
  g_type_class_add_private (G_OBJECT_CLASS (klass), sizeof (OwlTreeModelSlicePrivate));
}

static void
owl_tree_model_slice_tree_model_init (GtkTreeModelIface *iface)
{
  iface->get_flags = owl_tree_model_slice_get_flags;
  iface->get_n_columns = owl_tree_model_slice_get_n_columns;
  iface->get_column_type = owl_tree_model_slice_get_column_type;
  iface->get_iter = owl_tree_model_slice_get_iter;
  //iface->get_path = owl_tree_model_slice_get_path;
  iface->get_value = owl_tree_model_slice_get_value;
  iface->iter_next = owl_tree_model_slice_iter_next;
  iface->iter_children = owl_tree_model_slice_iter_children;
  iface->iter_has_child = owl_tree_model_slice_iter_has_child;
  iface->iter_n_children = owl_tree_model_slice_iter_n_children;
  iface->iter_nth_child = owl_tree_model_slice_iter_nth_child;
  iface->iter_parent = owl_tree_model_slice_iter_parent;
  iface->ref_node = owl_tree_model_slice_ref_node;
  iface->unref_node = owl_tree_model_slice_unref_node;
}

static GtkTreeModelFlags
owl_tree_model_slice_get_flags (GtkTreeModel *model)
{
  OwlTreeModelSlice *slice = OWL_TREE_MODEL_SLICE (model);

  g_return_val_if_fail (slice != NULL, 0);
  g_return_val_if_fail (slice->priv->child_model != NULL, 0);

  return gtk_tree_model_get_flags (slice->priv->child_model) | GTK_TREE_MODEL_LIST_ONLY;
}

static gint
owl_tree_model_slice_get_n_columns (GtkTreeModel *model)
{
  OwlTreeModelSlice *slice = OWL_TREE_MODEL_SLICE (model);
  
  g_return_val_if_fail (slice != NULL, 0);
  g_return_val_if_fail (slice->priv->child_model != NULL, 0);

  return gtk_tree_model_get_n_columns (slice->priv->child_model);
}

static GType
owl_tree_model_slice_get_column_type (GtkTreeModel *model, gint index)
{
  OwlTreeModelSlice *slice = OWL_TREE_MODEL_SLICE (model);
  
  g_return_val_if_fail (slice != NULL, G_TYPE_INVALID);
  g_return_val_if_fail (slice->priv->child_model != NULL, G_TYPE_INVALID);

  return gtk_tree_model_get_column_type (slice->priv->child_model, index);
}

static GtkTreePath*
convert_to_child (OwlTreeModelSlice *slice, GtkTreePath *path)
{
  GtkTreePath *new_path;
  gint depth;
  gint *indices;
  
  g_assert (slice);
  g_assert (path);

  if (slice->priv->root == NULL)
    return gtk_tree_path_copy (path);

  new_path = gtk_tree_path_copy (slice->priv->root);
  depth = gtk_tree_path_get_depth (path);
  indices = gtk_tree_path_get_indices (path);
  while (depth--)
    gtk_tree_path_append_index (new_path, *indices++);
  return new_path;
}

static gboolean
owl_tree_model_slice_get_iter (GtkTreeModel *model,
                               GtkTreeIter  *iter,
                               GtkTreePath  *path)
{
  OwlTreeModelSlice *slice = OWL_TREE_MODEL_SLICE (model);
  GtkTreePath *child_path;
  gboolean res;

  g_return_val_if_fail (slice != NULL, FALSE);
  g_return_val_if_fail (slice->priv->child_model != NULL, FALSE);

  child_path = convert_to_child (slice, path);  
  res = gtk_tree_model_get_iter (slice->priv->child_model, iter, child_path);
  gtk_tree_path_free (child_path);
  return res;
}

static void
owl_tree_model_slice_get_value (GtkTreeModel *model,
                                GtkTreeIter *iter,
                                gint column,
                                GValue *value)
{
  OwlTreeModelSlice *slice = OWL_TREE_MODEL_SLICE (model);

  g_return_if_fail (slice != NULL);
  g_return_if_fail (slice->priv->child_model != NULL);

  gtk_tree_model_get_value (slice->priv->child_model, iter, column, value);
}

static gboolean
owl_tree_model_slice_iter_next (GtkTreeModel *model,
                                GtkTreeIter *iter)
{
  OwlTreeModelSlice *slice = OWL_TREE_MODEL_SLICE (model);

  g_return_val_if_fail (slice != NULL, FALSE);
  g_return_val_if_fail (slice->priv->child_model != NULL, FALSE);

  return gtk_tree_model_iter_next (slice->priv->child_model, iter);
}

static gboolean
owl_tree_model_slice_iter_children (GtkTreeModel *model,
                                    GtkTreeIter *iter,
                                    GtkTreeIter *parent)
{
  OwlTreeModelSlice *slice = OWL_TREE_MODEL_SLICE (model);

  g_return_val_if_fail (slice != NULL, FALSE);
  g_return_val_if_fail (slice->priv->child_model != NULL, FALSE);

  if (parent == NULL)
    return gtk_tree_model_get_iter_first (model, iter);
  else
    return FALSE;
}

static gboolean
owl_tree_model_slice_iter_has_child (GtkTreeModel *model,
                                     GtkTreeIter *iter)
{
  OwlTreeModelSlice *slice = OWL_TREE_MODEL_SLICE (model);

  g_return_val_if_fail (slice != NULL, FALSE);
  g_return_val_if_fail (slice->priv->child_model != NULL, FALSE);

  return FALSE;
}

static gint
owl_tree_model_slice_iter_n_children  (GtkTreeModel *model,
                                       GtkTreeIter *iter)
{
  OwlTreeModelSlice *slice = OWL_TREE_MODEL_SLICE (model);

  g_return_val_if_fail (slice != NULL, 0);
  g_return_val_if_fail (slice->priv->child_model != NULL, 0);

  if (iter) {
    return 0;
  } else {
    GtkTreeIter child_iter;
    if (!gtk_tree_model_get_iter (slice->priv->child_model, &child_iter, slice->priv->root)) {
      g_warning ("Cannot get child iterator");
      return 0;
    }
    return gtk_tree_model_iter_n_children (slice->priv->child_model, &child_iter);
  }
}


static gboolean
owl_tree_model_slice_iter_nth_child (GtkTreeModel *model,
                                     GtkTreeIter *iter,
                                     GtkTreeIter *parent,
                                     gint n)
{
  OwlTreeModelSlice *slice = OWL_TREE_MODEL_SLICE (model);

  g_return_val_if_fail (slice != NULL, FALSE);
  g_return_val_if_fail (slice->priv->child_model != NULL, FALSE);

  if (parent != NULL)
    return FALSE;
  else
    return gtk_tree_model_iter_nth_child (slice->priv->child_model, iter, parent, n);
}

static gboolean
owl_tree_model_slice_iter_parent (GtkTreeModel *model, GtkTreeIter *iter, GtkTreeIter *child)
{
  OwlTreeModelSlice *slice = OWL_TREE_MODEL_SLICE (model);

  g_return_val_if_fail (slice != NULL, FALSE);
  g_return_val_if_fail (slice->priv->child_model != NULL, FALSE);

  return FALSE;
}

static void
owl_tree_model_slice_ref_node (GtkTreeModel *model, GtkTreeIter *iter)
{
  OwlTreeModelSlice *slice = OWL_TREE_MODEL_SLICE (model);

  g_return_if_fail (slice != NULL);
  g_return_if_fail (slice->priv->child_model != NULL);

  gtk_tree_model_ref_node (slice->priv->child_model, iter);
}

static void
owl_tree_model_slice_unref_node (GtkTreeModel *model, GtkTreeIter *iter)
{
  OwlTreeModelSlice *slice = OWL_TREE_MODEL_SLICE (model);

  g_return_if_fail (slice != NULL);
  g_return_if_fail (slice->priv->child_model != NULL);

  gtk_tree_model_unref_node (slice->priv->child_model, iter);
}

GtkTreeModel *
owl_tree_model_slice_new (GtkTreeModel *child_model,
                          GtkTreePath  *root)
{
  OwlTreeModelSlice *slice;

  g_return_val_if_fail (child_model != NULL, NULL);

  slice = g_object_new (OWL_TYPE_TREE_MODEL_SLICE, NULL);

  slice->priv->child_model = child_model;
  if (root) {
    slice->priv->root = gtk_tree_path_copy (root);
  } else {
    slice->priv->root = NULL;
  }
  return (GtkTreeModel *)slice;
}

GtkTreeModel *
owl_tree_model_slice_get_model (OwlTreeModelSlice *slice)
{
  g_return_val_if_fail (OWL_IS_TREE_MODEL_SLICE (slice), NULL);

  return slice->priv->child_model;
}

void
owl_tree_model_slice_set_root (OwlTreeModelSlice *slice, GtkTreePath *root)
{
  g_return_if_fail (OWL_IS_TREE_MODEL_SLICE (slice));
  g_return_if_fail (OWL_IS_TREE_MODEL_SLICE (slice->priv->child_model));

  if (root) {
    slice->priv->root = gtk_tree_path_copy (root);
  } else {
    slice->priv->root = NULL;
  }
  /* TODO: emit change events */
}

#if 0
/* Not sure we need these */
void
owl_tree_model_slice_convert_child_iter_to_iter (OwlTreeModelSlice           *slice,
                                                                GtkTreeIter                  *slice_iter,
                                                                GtkTreeIter                  *child_iter);
void          owl_tree_model_slice_convert_iter_to_child_iter (OwlTreeModelSlice           *slice,
                                                                GtkTreeIter                  *child_iter,
                                                                GtkTreeIter                  *slice_iter);
#endif


/* TODO */
GtkTreePath  *owl_tree_model_slice_convert_child_path_to_path (OwlTreeModelSlice           *slice,
                                                                GtkTreePath                  *child_path);

GtkTreePath  *
owl_tree_model_slice_convert_path_to_child_path (OwlTreeModelSlice *slice, GtkTreePath *slice_path)
{
  g_return_val_if_fail (OWL_IS_TREE_MODEL_SLICE (slice), NULL);
  g_return_val_if_fail (slice->priv->child_model != NULL, NULL);
  g_return_val_if_fail (slice_path != NULL, NULL);

  return convert_to_child (slice, slice_path);
}