Introduce LdDiagramConnection.

1 files changed, 333 insertions, 0 deletions

diff --git a/liblogdiag/ld-diagram-connection.c b/liblogdiag/ld-diagram-connection.c
new file mode 100644
index 0000000..04e5888
--- /dev/null
+++ b/liblogdiag/ld-diagram-connection.c
@@ -0,0 +1,333 @@
+/*
+ * ld-diagram-connection.c
+ *
+ * This file is a part of logdiag.
+ * Copyright Přemysl Janouch 2011. All rights reserved.
+ *
+ * See the file LICENSE for licensing information.
+ *
+ */
+
+#include <string.h>
+
+#include "liblogdiag.h"
+#include "config.h"
+
+
+/**
+ * SECTION:ld-diagram-connection
+ * @short_description: A connection object
+ * @see_also: #LdDiagramObject
+ *
+ * #LdDiagramConnection is an implementation of #LdDiagramObject.
+ */
+
+typedef struct _SetPointsActionData SetPointsActionData;
+
+/*
+ * SetPointsActionData:
+ * @self: the object this action has happened on.
+ * @old_node: the old node.
+ * @new_node: the new node.
+ */
+struct _SetPointsActionData
+{
+	LdDiagramConnection *self;
+	JsonNode *old_node;
+	JsonNode *new_node;
+};
+
+enum
+{
+	PROP_0,
+	PROP_POINTS
+};
+
+static void ld_diagram_connection_get_property (GObject *object,
+	guint property_id, GValue *value, GParamSpec *pspec);
+static void ld_diagram_connection_set_property (GObject *object,
+	guint property_id, const GValue *value, GParamSpec *pspec);
+
+static gboolean read_point_node (JsonNode *node, LdPoint *point);
+static gboolean read_double_node (JsonNode *node, gdouble *value);
+
+static void on_set_points_undo (gpointer user_data);
+static void on_set_points_redo (gpointer user_data);
+static void on_set_points_destroy (gpointer user_data);
+
+
+G_DEFINE_TYPE (LdDiagramConnection, ld_diagram_connection,
+	LD_TYPE_DIAGRAM_OBJECT);
+
+static void
+ld_diagram_connection_class_init (LdDiagramConnectionClass *klass)
+{
+	GObjectClass *object_class;
+	GParamSpec *pspec;
+
+	object_class = G_OBJECT_CLASS (klass);
+	object_class->get_property = ld_diagram_connection_get_property;
+	object_class->set_property = ld_diagram_connection_set_property;
+
+/**
+ * LdDiagramConnection:points:
+ *
+ * Points defining this connection.
+ */
+	pspec = g_param_spec_boxed ("points", "Points",
+		"Points defining this connection.",
+		LD_TYPE_POINT_ARRAY, G_PARAM_READWRITE);
+	g_object_class_install_property (object_class, PROP_POINTS, pspec);
+}
+
+static void
+ld_diagram_connection_init (LdDiagramConnection *self)
+{
+}
+
+static void
+ld_diagram_connection_get_property (GObject *object, guint property_id,
+	GValue *value, GParamSpec *pspec)
+{
+	LdDiagramConnection *self;
+
+	self = LD_DIAGRAM_CONNECTION (object);
+	switch (property_id)
+	{
+		LdPointArray *points;
+
+	case PROP_POINTS:
+		points = ld_diagram_connection_get_points (self);
+		g_value_set_boxed_take_ownership (value, points);
+		break;
+	default:
+		G_OBJECT_WARN_INVALID_PROPERTY_ID (object, property_id, pspec);
+	}
+}
+
+static void
+ld_diagram_connection_set_property (GObject *object, guint property_id,
+	const GValue *value, GParamSpec *pspec)
+{
+	LdDiagramConnection *self;
+
+	self = LD_DIAGRAM_CONNECTION (object);
+	switch (property_id)
+	{
+	case PROP_POINTS:
+		ld_diagram_connection_set_points (self, g_value_get_boxed (value));
+		break;
+	default:
+		G_OBJECT_WARN_INVALID_PROPERTY_ID (object, property_id, pspec);
+	}
+}
+
+
+/**
+ * ld_diagram_connection_new:
+ * @storage: a storage backend.
+ *
+ * Return value: a new #LdDiagramConnection object.
+ */
+LdDiagramConnection *
+ld_diagram_connection_new (JsonObject *storage)
+{
+	LdDiagramConnection *self;
+
+	self = g_object_new (LD_TYPE_DIAGRAM_CONNECTION, "storage", storage, NULL);
+	return self;
+}
+
+#define WARN_NODE_TYPE(node, type) \
+	G_STMT_START { \
+		g_warning ("%s: unable to read a value of type `%s' from node" \
+			" of type `%s'", G_STRLOC, g_type_name (type), \
+			json_node_type_name (node)); \
+	} G_STMT_END
+
+/**
+ * ld_diagram_connection_get_points:
+ * @self: an #LdDiagramConnection object.
+ *
+ * Get points defining this connection. Coordinates of the points are relative
+ * to the inherited #LdDiagramObject:x and #LdDiagramObject:y properties.
+ *
+ * Return value: (transfer full): a point array.
+ */
+LdPointArray *
+ld_diagram_connection_get_points (LdDiagramConnection *self)
+{
+	LdPointArray *points;
+	JsonObject *storage;
+	JsonNode *node;
+	JsonArray *array;
+	GList *point_node_list, *iter;
+
+	g_return_val_if_fail (LD_IS_DIAGRAM_CONNECTION (self), NULL);
+
+	storage = ld_diagram_object_get_storage (LD_DIAGRAM_OBJECT (self));
+	node = json_object_get_member (storage, "points");
+	if (!node || json_node_is_null (node))
+		return ld_point_array_new (0);
+	if (!JSON_NODE_HOLDS_ARRAY (node))
+	{
+		WARN_NODE_TYPE (node, LD_TYPE_POINT_ARRAY);
+		return ld_point_array_new (0);
+	}
+
+	array = json_node_get_array (node);
+	point_node_list = json_array_get_elements (array);
+	points = ld_point_array_new (json_array_get_length (array));
+
+	points->num_points = 0;
+	for (iter = point_node_list; iter; iter = g_list_next (iter))
+	{
+		if (read_point_node (iter->data, &points->points[points->num_points]))
+			points->num_points++;
+	}
+	return points;
+}
+
+static gboolean
+read_point_node (JsonNode *node, LdPoint *point)
+{
+	JsonArray *array;
+	JsonNode *x_node, *y_node;
+
+	g_return_val_if_fail (node != NULL, FALSE);
+	g_return_val_if_fail (point != NULL, FALSE);
+
+	if (!JSON_NODE_HOLDS_ARRAY (node))
+	{
+		WARN_NODE_TYPE (node, LD_TYPE_POINT);
+		return FALSE;
+	}
+	array = json_node_get_array (node);
+	if (json_array_get_length (array) < 2)
+	{
+		g_warning ("%s: too few values for a point", G_STRLOC);
+		return FALSE;
+	}
+
+	x_node = json_array_get_element (array, 0);
+	y_node = json_array_get_element (array, 1);
+
+	return read_double_node (x_node, &point->x)
+		&& read_double_node (y_node, &point->y);
+}
+
+static gboolean
+read_double_node (JsonNode *node, gdouble *value)
+{
+	GValue double_value, json_value;
+
+	g_return_val_if_fail (node != NULL, FALSE);
+	g_return_val_if_fail (value != NULL, FALSE);
+
+	if (!JSON_NODE_HOLDS_VALUE (node) || !g_value_type_transformable
+		(json_node_get_value_type (node), G_TYPE_DOUBLE))
+	{
+		WARN_NODE_TYPE (node, G_TYPE_DOUBLE);
+		return FALSE;
+	}
+
+	memset (&json_value, 0, sizeof (GValue));
+	memset (&double_value, 0, sizeof (GValue));
+
+	json_node_get_value (node, &json_value);
+	g_value_init (&double_value, G_TYPE_DOUBLE);
+	g_value_transform (&json_value, &double_value);
+	*value = g_value_get_double (&double_value);
+
+	g_value_unset (&json_value);
+	g_value_unset (&double_value);
+	return TRUE;
+}
+
+/**
+ * ld_diagram_connection_set_points:
+ * @self: an #LdDiagramConnection object.
+ * @points: a point array.
+ *
+ * Set the points defining this connection.
+ */
+void
+ld_diagram_connection_set_points (LdDiagramConnection *self,
+	const LdPointArray *points)
+{
+	LdUndoAction *action;
+	SetPointsActionData *action_data;
+	JsonNode *node;
+	JsonObject *storage;
+	JsonArray *array, *point_array;
+	guint i;
+
+	g_return_if_fail (LD_IS_DIAGRAM_CONNECTION (self));
+	g_return_if_fail (points != NULL);
+
+	storage = ld_diagram_object_get_storage (LD_DIAGRAM_OBJECT (self));
+	array = json_array_new ();
+	for (i = 0; i < points->num_points; i++)
+	{
+		point_array = json_array_new ();
+		json_array_add_double_element (point_array, points->points[i].x);
+		json_array_add_double_element (point_array, points->points[i].y);
+		json_array_add_array_element (array, point_array);
+	}
+
+	action_data = g_slice_new (SetPointsActionData);
+	action_data->self = g_object_ref (self);
+
+	node = json_object_get_member (storage, "points");
+	action_data->old_node = node ? json_node_copy (node) : NULL;
+
+	node = json_node_new (JSON_NODE_ARRAY);
+	json_node_set_array (node, array);
+	action_data->new_node = json_node_copy (node);
+
+	json_object_set_member (storage, "points", node);
+
+	action = ld_undo_action_new (on_set_points_undo, on_set_points_redo,
+		on_set_points_destroy, action_data);
+	ld_diagram_object_changed (LD_DIAGRAM_OBJECT (self), action);
+	g_object_unref (action);
+}
+
+static void
+on_set_points_undo (gpointer user_data)
+{
+	SetPointsActionData *data;
+	JsonObject *storage;
+
+	data = user_data;
+	storage = ld_diagram_object_get_storage (LD_DIAGRAM_OBJECT (data->self));
+
+	json_object_set_member (storage, "points", json_node_copy (data->old_node));
+}
+
+static void
+on_set_points_redo (gpointer user_data)
+{
+	SetPointsActionData *data;
+	JsonObject *storage;
+
+	data = user_data;
+	storage = ld_diagram_object_get_storage (LD_DIAGRAM_OBJECT (data->self));
+
+	json_object_set_member (storage, "points", json_node_copy (data->new_node));
+}
+
+static void
+on_set_points_destroy (gpointer user_data)
+{
+	SetPointsActionData *data;
+
+	data = user_data;
+	g_object_unref (data->self);
+	if (data->old_node)
+		json_node_free (data->old_node);
+	if (data->new_node)
+		json_node_free (data->new_node);
+	g_slice_free (SetPointsActionData, data);
+}
+