/*
 * ***** 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/nodes/deg_node_id.cc
 *  \ingroup depsgraph
 */

#include "intern/nodes/deg_node_id.h"

#include <stdio.h>
#include <cstring>  /* required for STREQ later on. */

#include "BLI_utildefines.h"
#include "BLI_ghash.h"

extern "C" {
#include "DNA_ID.h"
#include "DNA_anim_types.h"

#include "BKE_animsys.h"
#include "BKE_library.h"
}

#include "DEG_depsgraph.h"

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

#include "util/deg_util_foreach.h"

namespace DEG {

IDDepsNode::ComponentIDKey::ComponentIDKey(eDepsNode_Type type,
                                           const char *name)
        : type(type), name(name)
{
}

bool IDDepsNode::ComponentIDKey::operator== (const ComponentIDKey &other) const
{
	return type == other.type &&
		STREQ(name, other.name);
}

static unsigned int id_deps_node_hash_key(const void *key_v)
{
	const IDDepsNode::ComponentIDKey *key =
	        reinterpret_cast<const IDDepsNode::ComponentIDKey *>(key_v);
	return BLI_ghashutil_combine_hash(BLI_ghashutil_uinthash(key->type),
	                                  BLI_ghashutil_strhash_p(key->name));
}

static bool id_deps_node_hash_key_cmp(const void *a, const void *b)
{
	const IDDepsNode::ComponentIDKey *key_a =
	        reinterpret_cast<const IDDepsNode::ComponentIDKey *>(a);
	const IDDepsNode::ComponentIDKey *key_b =
	        reinterpret_cast<const IDDepsNode::ComponentIDKey *>(b);
	return !(*key_a == *key_b);
}

static void id_deps_node_hash_key_free(void *key_v)
{
	typedef IDDepsNode::ComponentIDKey ComponentIDKey;
	ComponentIDKey *key = reinterpret_cast<ComponentIDKey *>(key_v);
	OBJECT_GUARDED_DELETE(key, ComponentIDKey);
}

static void id_deps_node_hash_value_free(void *value_v)
{
	ComponentDepsNode *comp_node = reinterpret_cast<ComponentDepsNode *>(value_v);
	OBJECT_GUARDED_DELETE(comp_node, ComponentDepsNode);
}

/* Initialize 'id' node - from pointer data given. */
void IDDepsNode::init(const ID *id, const char *UNUSED(subdata))
{
	BLI_assert(id != NULL);
	/* Store ID-pointer. */
	id_orig = (ID *)id;
	eval_flags = 0;
	linked_state = DEG_ID_LINKED_INDIRECTLY;

	components = BLI_ghash_new(id_deps_node_hash_key,
	                           id_deps_node_hash_key_cmp,
	                           "Depsgraph id components hash");
}

void IDDepsNode::init_copy_on_write(ID *id_cow_hint)
{
	/* Early output for non-copy-on-write case: we keep CoW pointer same as
	 * an original one.
	 */
	if (!DEG_depsgraph_use_copy_on_write()) {
		UNUSED_VARS(id_cow_hint);
		id_cow = id_orig;
		return;
	}
	/* Create pointer as early as possible, so we can use it for function
	 * bindings. Rest of data we'll be copying to the new datablock when
	 * it is actually needed.
	 */
	if (id_cow_hint != NULL) {
		// BLI_assert(deg_copy_on_write_is_needed(id_orig));
		if (deg_copy_on_write_is_needed(id_orig)) {
			id_cow = id_cow_hint;
		}
		else {
			id_cow = id_orig;
		}
	}
	else if (deg_copy_on_write_is_needed(id_orig)) {
		id_cow = (ID *)BKE_libblock_alloc_notest(GS(id_orig->name));
		DEG_COW_PRINT("Create shallow copy for %s: id_orig=%p id_cow=%p\n",
		              id_orig->name, id_orig, id_cow);
		deg_tag_copy_on_write_id(id_cow, id_orig);
	}
	else {
		id_cow = id_orig;
	}
}

/* Free 'id' node. */
IDDepsNode::~IDDepsNode()
{
	destroy();
}

void IDDepsNode::destroy()
{
	if (id_orig == NULL) {
		return;
	}

	BLI_ghash_free(components,
	               id_deps_node_hash_key_free,
	               id_deps_node_hash_value_free);

	/* Free memory used by this CoW ID. */
	if (id_cow != id_orig && id_cow != NULL) {
		deg_free_copy_on_write_datablock(id_cow);
		MEM_freeN(id_cow);
		DEG_COW_PRINT("Destroy CoW for %s: id_orig=%p id_cow=%p\n",
		              id_orig->name, id_orig, id_cow);
	}

	/* Tag that the node is freed. */
	id_orig = NULL;
}

string IDDepsNode::identifier() const
{
	char orig_ptr[24], cow_ptr[24];
	BLI_snprintf(orig_ptr, sizeof(orig_ptr), "%p", id_orig);
	BLI_snprintf(cow_ptr, sizeof(cow_ptr), "%p", id_cow);
	return string(nodeTypeAsString(type)) + " : " + name +
	        " (orig: " + orig_ptr + ", eval: " + cow_ptr + ")";
}

ComponentDepsNode *IDDepsNode::find_component(eDepsNode_Type type,
                                              const char *name) const
{
	ComponentIDKey key(type, name);
	return reinterpret_cast<ComponentDepsNode *>(BLI_ghash_lookup(components, &key));
}

ComponentDepsNode *IDDepsNode::add_component(eDepsNode_Type type,
                                             const char *name)
{
	ComponentDepsNode *comp_node = find_component(type, name);
	if (!comp_node) {
		DepsNodeFactory *factory = deg_type_get_factory(type);
		comp_node = (ComponentDepsNode *)factory->create_node(this->id_orig, "", name);

		/* Register. */
		ComponentIDKey *key = OBJECT_GUARDED_NEW(ComponentIDKey, type, name);
		BLI_ghash_insert(components, key, comp_node);
		comp_node->owner = this;
	}
	return comp_node;
}

void IDDepsNode::tag_update(Depsgraph *graph)
{
	GHASH_FOREACH_BEGIN(ComponentDepsNode *, comp_node, components)
	{
		comp_node->tag_update(graph);
	}
	GHASH_FOREACH_END();
}

void IDDepsNode::finalize_build(Depsgraph *graph)
{
	/* Finalize build of all components. */
	GHASH_FOREACH_BEGIN(ComponentDepsNode *, comp_node, components)
	{
		comp_node->finalize_build(graph);
	}
	GHASH_FOREACH_END();
}

}  // namespace DEG