/*
 * ***** BEGIN GPL LICENSE BLOCK *****
 *
 * 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 2
 * 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, write to the Free Software Foundation,
 * Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301, USA.
 *
 * The Original Code is Copyright (C) 2013 Blender Foundation.
 * All rights reserved.
 *
 * Original Author: Joshua Leung
 * Contributor(s): None Yet
 *
 * ***** END GPL LICENSE BLOCK *****
 */

/** \file blender/depsgraph/intern/depsgraph_query.cc
 *  \ingroup depsgraph
 *
 * Implementation of Querying and Filtering API's
 */

#include "MEM_guardedalloc.h"

extern "C" {
#include <string.h> // XXX: memcpy

#include "BLI_utildefines.h"
#include "BKE_idcode.h"
#include "BKE_main.h"
#include "BLI_listbase.h"

#include "BKE_action.h" // XXX: BKE_pose_channel_from_name
} /* extern "C" */

#include "DNA_object_types.h"
#include "DNA_scene_types.h"

#include "RNA_access.h"

#include "DEG_depsgraph.h"
#include "DEG_depsgraph_query.h"

#include "intern/eval/deg_eval_copy_on_write.h"
#include "intern/depsgraph_intern.h"
#include "intern/nodes/deg_node_id.h"

struct Scene *DEG_get_input_scene(const Depsgraph *graph)
{
	const DEG::Depsgraph *deg_graph = reinterpret_cast<const DEG::Depsgraph *>(graph);
	return deg_graph->scene;
}

struct ViewLayer *DEG_get_input_view_layer(const Depsgraph *graph)
{
	const DEG::Depsgraph *deg_graph = reinterpret_cast<const DEG::Depsgraph *>(graph);
	return deg_graph->view_layer;
}

eEvaluationMode DEG_get_mode(const Depsgraph *graph)
{
	const DEG::Depsgraph *deg_graph = reinterpret_cast<const DEG::Depsgraph *>(graph);
	return deg_graph->mode;
}

float DEG_get_ctime(const Depsgraph *graph)
{
	const DEG::Depsgraph *deg_graph = reinterpret_cast<const DEG::Depsgraph *>(graph);
	return deg_graph->ctime;
}


bool DEG_id_type_tagged(Main *bmain, short id_type)
{
	return bmain->id_tag_update[BKE_idcode_to_index(id_type)] != 0;
}

short DEG_get_eval_flags_for_id(const Depsgraph *graph, ID *id)
{
	if (graph == NULL) {
		/* Happens when converting objects to mesh from a python script
		 * after modifying scene graph.
		 *
		 * Currently harmless because it's only called for temporary
		 * objects which are out of the DAG anyway.
		 */
		return 0;
	}

	const DEG::Depsgraph *deg_graph = reinterpret_cast<const DEG::Depsgraph *>(graph);
	const DEG::IDDepsNode *id_node = deg_graph->find_id_node(id);
	if (id_node == NULL) {
		/* TODO(sergey): Does it mean we need to check set scene? */
		return 0;
	}

	return id_node->eval_flags;
}

Scene *DEG_get_evaluated_scene(const Depsgraph *graph)
{
	const DEG::Depsgraph *deg_graph =
	        reinterpret_cast<const DEG::Depsgraph *>(graph);
	Scene *scene_cow = deg_graph->scene_cow;
	/* TODO(sergey): Shall we expand datablock here? Or is it OK to assume
	 * that calleer is OK with just a pointer in case scene is not up[dated
	 * yet?
	 */
	BLI_assert(DEG::deg_copy_on_write_is_expanded(&scene_cow->id));
	return scene_cow;
}

ViewLayer *DEG_get_evaluated_view_layer(const Depsgraph *graph)
{
	const DEG::Depsgraph *deg_graph =
	        reinterpret_cast<const DEG::Depsgraph *>(graph);
	Scene *scene_cow = DEG_get_evaluated_scene(graph);
	/* Do name-based lookup. */
	/* TODO(sergey): Can this be optimized? */
	ViewLayer *view_layer_orig = deg_graph->view_layer;
	ViewLayer *view_layer_cow =
	        (ViewLayer *)BLI_findstring(&scene_cow->view_layers,
	                                     view_layer_orig->name,
	                                     offsetof(ViewLayer, name));
	BLI_assert(view_layer_cow != NULL);
	return view_layer_cow;
}

Object *DEG_get_evaluated_object(const Depsgraph *depsgraph, Object *object)
{
	return (Object *)DEG_get_evaluated_id(depsgraph, &object->id);
}

ID *DEG_get_evaluated_id(const Depsgraph *depsgraph, ID *id)
{
	if (id == NULL) {
		return NULL;
	}
	/* TODO(sergey): This is a duplicate of Depsgraph::get_cow_id(),
	 * but here we never do assert, since we don't know nature of the
	 * incoming ID datablock.
	 */
	const DEG::Depsgraph *deg_graph = (const DEG::Depsgraph *)depsgraph;
	const DEG::IDDepsNode *id_node = deg_graph->find_id_node(id);
	if (id_node == NULL) {
		return id;
	}
	return id_node->id_cow;
}

/* Get evaluated version of data pointed to by RNA pointer */
void DEG_get_evaluated_rna_pointer(const Depsgraph *depsgraph, const PointerRNA *ptr, PointerRNA *r_ptr_eval)
{
	if ((ptr == NULL) || (r_ptr_eval == NULL)) {
		return;
	}
	if ((ptr->id.data == ptr->data)) {
		ID *orig_id = (ID *)ptr->id.data;
		ID *cow_id = DEG_get_evaluated_id(depsgraph, orig_id);
		/* For ID pointers, it's easy... */
		r_ptr_eval->id.data = (void *)cow_id;
		r_ptr_eval->data = (void *)cow_id;
		r_ptr_eval->type = ptr->type;
	}
	else {
		/* XXX: Hack for common cases... Proper fix needs to be made still... A very tricky problem though! */
		if (ptr->type == &RNA_PoseBone) {
			const Object *ob_eval = (Object *)DEG_get_evaluated_id(depsgraph, (ID *)ptr->id.data);
			bPoseChannel *pchan = (bPoseChannel *)ptr->data;
			const bPoseChannel *pchan_eval = BKE_pose_channel_find_name(ob_eval->pose, pchan->name);
			/* XXX: Hack - This is just temporary... but this case must be supported. */
			r_ptr_eval->id.data = (void *)&ob_eval->id;
			r_ptr_eval->data = (void *)pchan_eval;
			r_ptr_eval->type = ptr->type;
		}
		else {
			/* FIXME: Maybe we should try resolving paths, or using some kind of depsgraph lookup? */
			// XXX: For now, just use dirty hack, and hope it doesn't cause nasty issues.
			*r_ptr_eval = *ptr;
		}
	}
}

Object *DEG_get_original_object(Object *object)
{
	return (Object *)DEG_get_original_id(&object->id);
}

ID *DEG_get_original_id(ID *id)
{
	if (id == NULL) {
		return NULL;
	}
	if (id->orig_id == NULL) {
		return id;
	}
	BLI_assert((id->tag & LIB_TAG_COPY_ON_WRITE) != 0);
	return (ID *)id->orig_id;
}