+/* PSPPIRE - a graphical user interface for PSPP.
+ Copyright (C) 2008 Free Software Foundation
+
+ This program is free software: you can redistribute it and/or modify
+ it under the terms of the GNU General Public License as published by
+ the Free Software Foundation, either version 3 of the License, or
+ (at your option) any later version.
+
+ This program 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 General Public License for more details.
+
+ You should have received a copy of the GNU General Public License
+ along with this program. If not, see <http://www.gnu.org/licenses/>. */
+
+#include <config.h>
+#include <string.h>
+#include <stdlib.h>
+
+#include <libpspp/tower.h>
+#include <libpspp/pool.h>
+#include "psppire-axis-impl.h"
+#include <math.h>
+
+
+/* --- prototypes --- */
+static void psppire_axis_impl_class_init (PsppireAxisImplClass *class);
+static void psppire_axis_impl_init (PsppireAxisImpl *axis);
+static void psppire_axis_impl_finalize (GObject *object);
+
+
+/* --- variables --- */
+static GObjectClass *parent_class = NULL;
+
+
+struct axis_node
+{
+ struct tower_node pixel_node;
+ struct tower_node unit_node;
+};
+
+static gint
+get_unit_at_pixel (const PsppireAxis *axis, glong pixel)
+{
+ PsppireAxisImpl *a = PSPPIRE_AXIS_IMPL (axis);
+
+ unsigned long int start;
+
+ struct tower_node *n = tower_lookup (&a->pixel_tower, pixel, &start);
+
+ struct axis_node *an = tower_data (n, struct axis_node, pixel_node);
+
+ gfloat fraction = (pixel - start) / (gfloat) tower_node_get_size (&an->pixel_node);
+
+ return tower_node_get_level (&an->unit_node) + fraction * tower_node_get_size (&an->unit_node);
+}
+
+
+static gint
+unit_count (const PsppireAxis *axis)
+{
+ PsppireAxisImpl *a = PSPPIRE_AXIS_IMPL (axis);
+
+ return tower_height (&a->unit_tower);
+}
+
+
+/* Returns the pixel at the start of UNIT */
+static glong
+pixel_start (const PsppireAxis *axis, gint unit)
+{
+ gfloat fraction;
+ PsppireAxisImpl *a = PSPPIRE_AXIS_IMPL (axis);
+ struct tower_node *n ;
+ struct axis_node *an;
+
+ unsigned long int start;
+
+ if ( unit < 0)
+ return -1;
+
+ if ( unit >= unit_count (axis))
+ return -1;
+
+ n = tower_lookup (&a->unit_tower, unit, &start);
+
+ an = tower_data (n, struct axis_node, unit_node);
+
+ fraction = (unit - start) / (gfloat) tower_node_get_size (&an->unit_node);
+
+ return tower_node_get_level (&an->pixel_node) +
+ nearbyintf (fraction * tower_node_get_size (&an->pixel_node));
+}
+
+
+static gint
+unit_size (const PsppireAxis *axis, gint unit)
+{
+ PsppireAxisImpl *a = PSPPIRE_AXIS_IMPL (axis);
+ struct tower_node *n ;
+ struct axis_node *an;
+
+ unsigned long int start;
+
+ if ( unit < 0)
+ return 0;
+
+ if ( unit >= unit_count (axis))
+ return 0;
+
+ n = tower_lookup (&a->unit_tower, unit, &start);
+
+ an = tower_data (n, struct axis_node, unit_node);
+
+ return nearbyintf (tower_node_get_size (&an->pixel_node)
+ / (float) tower_node_get_size (&an->unit_node));
+}
+
+
+static glong
+total_size (const PsppireAxis *axis)
+{
+ PsppireAxisImpl *a = PSPPIRE_AXIS_IMPL (axis);
+
+ return tower_height (&a->pixel_tower);
+}
+
+
+
+
+static void
+psppire_impl_iface_init (PsppireAxisIface *iface)
+{
+ iface->unit_size = unit_size;
+ iface->unit_count = unit_count;
+ iface->pixel_start = pixel_start;
+ iface->get_unit_at_pixel = get_unit_at_pixel;
+ iface->total_size = total_size;
+}
+
+/* --- functions --- */
+/**
+ * psppire_axis_impl_get_type:
+ * @returns: the type ID for accelerator groups.
+ */
+GType
+psppire_axis_impl_get_type (void)
+{
+ static GType object_type = 0;
+
+ if (!object_type)
+ {
+ static const GTypeInfo object_info = {
+ sizeof (PsppireAxisImplClass),
+ (GBaseInitFunc) NULL,
+ (GBaseFinalizeFunc) NULL,
+ (GClassInitFunc) psppire_axis_impl_class_init,
+ NULL, /* class_finalize */
+ NULL, /* class_data */
+ sizeof (PsppireAxisImpl),
+ 0, /* n_preallocs */
+ (GInstanceInitFunc) psppire_axis_impl_init,
+ };
+
+ static const GInterfaceInfo interface_info =
+ {
+ (GInterfaceInitFunc) psppire_impl_iface_init,
+ NULL,
+ NULL
+ };
+
+
+ object_type = g_type_register_static (G_TYPE_PSPPIRE_AXIS,
+ "PsppireAxisImpl",
+ &object_info, 0);
+
+
+ g_type_add_interface_static (object_type,
+ PSPPIRE_TYPE_AXIS_IFACE,
+ &interface_info);
+ }
+
+ return object_type;
+}
+
+static void
+psppire_axis_impl_class_init (PsppireAxisImplClass *class)
+{
+ GObjectClass *object_class = G_OBJECT_CLASS (class);
+ parent_class = g_type_class_peek_parent (class);
+
+ object_class->finalize = psppire_axis_impl_finalize;
+}
+
+
+static void
+psppire_axis_impl_init (PsppireAxisImpl *axis)
+{
+ tower_init (&axis->pixel_tower);
+ tower_init (&axis->unit_tower);
+
+ axis->pool = pool_create ();
+}
+
+
+static void
+psppire_axis_impl_finalize (GObject *object)
+{
+ PsppireAxisImpl *a = PSPPIRE_AXIS_IMPL (object);
+ pool_destroy (a->pool);
+
+ G_OBJECT_CLASS (parent_class)->finalize (object);
+}
+
+/**
+ * psppire_axis_impl_new:
+ * @returns: a new #PsppireAxisImpl object
+ *
+ * Creates a new #PsppireAxisImpl.
+ */
+PsppireAxisImpl*
+psppire_axis_impl_new (void)
+{
+ return g_object_new (G_TYPE_PSPPIRE_AXIS_IMPL, NULL);
+}
+
+
+\f
+
+void
+psppire_axis_impl_append (PsppireAxisImpl *a, gint size)
+{
+ psppire_axis_impl_append_n (a, 1, size);
+}
+
+
+void
+psppire_axis_impl_append_n (PsppireAxisImpl *a, gint n_units, gint size)
+{
+ struct axis_node *node = pool_alloc (a->pool, sizeof *node);
+
+
+ tower_insert (&a->unit_tower, n_units, &node->unit_node, NULL);
+ tower_insert (&a->pixel_tower, size * n_units, &node->pixel_node, NULL);
+}
+
+
+/* Split the node of both towers at POSN */
+static void
+split (PsppireAxisImpl *a, gint posn)
+{
+ unsigned long int existing_unit_size;
+ unsigned long int existing_pixel_size;
+ unsigned long int start;
+ gfloat fraction;
+ struct axis_node *new_node ;
+ struct tower_node *n = tower_lookup (&a->unit_tower, posn, &start);
+
+ struct axis_node *existing_node =
+ tower_data (n, struct axis_node, unit_node);
+
+ /* Nothing needs to be done, if the range element is already split here */
+ if ( posn - start == 0)
+ return;
+
+ existing_unit_size = tower_node_get_size (&existing_node->unit_node);
+ existing_pixel_size = tower_node_get_size (&existing_node->pixel_node);
+
+ fraction = (posn - start) / (gfloat) existing_unit_size;
+
+ new_node = pool_alloc (a->pool, sizeof (*new_node));
+
+ tower_resize (&a->unit_tower, &existing_node->unit_node, posn - start);
+
+ tower_resize (&a->pixel_tower, &existing_node->pixel_node,
+ nearbyintf (fraction * existing_pixel_size));
+
+ tower_insert (&a->unit_tower,
+ existing_unit_size - (posn - start),
+ &new_node->unit_node,
+ tower_next (&a->unit_tower, &existing_node->unit_node));
+
+
+ tower_insert (&a->pixel_tower,
+ nearbyintf (existing_pixel_size * (1 - fraction)),
+ &new_node->pixel_node,
+ tower_next (&a->pixel_tower, &existing_node->pixel_node));
+}
+
+
+/* Insert a new unit of size SIZE before POSN */
+void
+psppire_axis_impl_insert (PsppireAxisImpl *a, gint posn, gint size)
+{
+ struct tower_node *n;
+ unsigned long int start;
+ struct axis_node *before;
+ struct axis_node *new_node = pool_alloc (a->pool, sizeof (*new_node));
+
+ split (a, posn);
+
+ n = tower_lookup (&a->unit_tower, posn, &start);
+ g_assert (posn == start);
+
+ before = tower_data (n, struct axis_node, unit_node);
+
+ tower_insert (&a->unit_tower,
+ 1,
+ &new_node->unit_node,
+ &before->unit_node);
+
+
+ tower_insert (&a->pixel_tower,
+ size,
+ &new_node->pixel_node,
+ &before->pixel_node);
+}
+
+
+/* Make the element at POSN singular.
+ Return a pointer to the node for this element */
+static struct axis_node *
+make_single (PsppireAxisImpl *a, gint posn)
+{
+ unsigned long int start;
+ struct tower_node *n;
+ n = tower_lookup (&a->unit_tower, posn, &start);
+
+ if ( 1 != tower_node_get_size (n))
+ {
+ split (a, posn + 1);
+ n = tower_lookup (&a->unit_tower, posn, &start);
+
+ if ( 1 != tower_node_get_size (n))
+ {
+ split (a, posn);
+ n = tower_lookup (&a->unit_tower, posn, &start);
+ }
+ }
+
+ g_assert (1 == tower_node_get_size (n));
+
+
+ return tower_data (n, struct axis_node, unit_node);
+}
+
+void
+psppire_axis_impl_resize (PsppireAxisImpl *a, gint posn, gint size)
+{
+ struct axis_node *an = make_single (a, posn);
+
+ tower_resize (&a->pixel_tower, &an->pixel_node, size);
+}
+
+
+
+void
+psppire_axis_impl_clear (PsppireAxisImpl *a)
+{
+ pool_destroy (a->pool);
+ a->pool = pool_create ();
+
+ tower_init (&a->pixel_tower);
+ tower_init (&a->unit_tower);
+}
+
+
+
+void
+psppire_axis_impl_delete (PsppireAxisImpl *a, gint first, gint n_cases)
+{
+ gint i;
+ g_warning ("%s FIXME: This is an inefficient implementation", __FUNCTION__);
+
+ for (i = first; i < first + n_cases; ++i)
+ {
+ struct axis_node *an = make_single (a, i);
+
+ tower_delete (&a->unit_tower, &an->unit_node);
+ tower_delete (&a->pixel_tower, &an->pixel_node);
+ }
+}