/*
 * ***** 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): Sergey Sharybin
 *
 * ***** END GPL LICENSE BLOCK *****
 */

/** \file blender/depsgraph/intern/depsgraph.cc
 *  \ingroup depsgraph
 *
 * Core routines for how the Depsgraph works.
 */

#include "intern/depsgraph.h" /* own include */

#include "MEM_guardedalloc.h"

#include "BLI_utildefines.h"
#include "BLI_console.h"
#include "BLI_hash.h"
#include "BLI_ghash.h"
#include "BLI_listbase.h"

extern "C" {
#include "DNA_action_types.h"
#include "DNA_armature_types.h"
#include "DNA_constraint_types.h"
#include "DNA_key_types.h"
#include "DNA_object_types.h"
#include "DNA_sequence_types.h"

#include "BKE_depsgraph.h"

#include "RNA_access.h"
}

#include <algorithm>
#include <cstring>

#include "DEG_depsgraph.h"

#include "intern/nodes/deg_node.h"
#include "intern/nodes/deg_node_component.h"
#include "intern/nodes/deg_node_id.h"
#include "intern/nodes/deg_node_operation.h"
#include "intern/nodes/deg_node_time.h"

#include "intern/depsgraph_intern.h"
#include "util/deg_util_foreach.h"

namespace DEG {

static DEG_EditorUpdateIDCb deg_editor_update_id_cb = NULL;
static DEG_EditorUpdateSceneCb deg_editor_update_scene_cb = NULL;
static DEG_EditorUpdateScenePreCb deg_editor_update_scene_pre_cb = NULL;

/* TODO(sergey): Find a better place for this. */
template <typename T>
static void remove_from_vector(vector<T> *vector, const T& value)
{
	vector->erase(std::remove(vector->begin(), vector->end(), value),
	              vector->end());
}

Depsgraph::Depsgraph()
  : time_source(NULL),
    need_update(false),
    layers(0)
{
	BLI_spin_init(&lock);
	id_hash = BLI_ghash_ptr_new("Depsgraph id hash");
	entry_tags = BLI_gset_ptr_new("Depsgraph entry_tags");
}

Depsgraph::~Depsgraph()
{
	clear_id_nodes();
	BLI_ghash_free(id_hash, NULL, NULL);
	BLI_gset_free(entry_tags, NULL);
	if (time_source != NULL) {
		OBJECT_GUARDED_DELETE(time_source, TimeSourceDepsNode);
	}
	BLI_spin_end(&lock);
}

/* Query Conditions from RNA ----------------------- */

static bool pointer_to_component_node_criteria(
        const PointerRNA *ptr,
        const PropertyRNA *prop,
        ID **id,
        eDepsNode_Type *type,
        const char **subdata,
        eDepsOperation_Code *operation_code,
        const char **operation_name,
        int *operation_name_tag)
{
	if (ptr->type == NULL) {
		return false;
	}
	/* Set default values for returns. */
	*id = (ID *)ptr->id.data;
	*subdata = "";
	*operation_code = DEG_OPCODE_OPERATION;
	*operation_name = "";
	*operation_name_tag = -1;
	/* Handling of commonly known scenarios. */
	if (ptr->type == &RNA_PoseBone) {
		bPoseChannel *pchan = (bPoseChannel *)ptr->data;
		if (prop != NULL && RNA_property_is_idprop(prop)) {
			*type = DEG_NODE_TYPE_PARAMETERS;
			*operation_code = DEG_OPCODE_ID_PROPERTY;
			*operation_name = RNA_property_identifier((PropertyRNA *)prop);
			*operation_name_tag = -1;
		}
		else {
			/* Bone - generally, we just want the bone component. */
			*type = DEG_NODE_TYPE_BONE;
			*subdata = pchan->name;
		}
		return true;
	}
	else if (ptr->type == &RNA_Bone) {
		Bone *bone = (Bone *)ptr->data;
		/* armature-level bone, but it ends up going to bone component anyway */
		// NOTE: the ID in this case will end up being bArmature.
		*type = DEG_NODE_TYPE_BONE;
		*subdata = bone->name;
		return true;
	}
	else if (RNA_struct_is_a(ptr->type, &RNA_Constraint)) {
		Object *object = (Object *)ptr->id.data;
		bConstraint *con = (bConstraint *)ptr->data;
		/* Check whether is object or bone constraint. */
		/* NOTE: Currently none of the area can address transform of an object
		 * at a given constraint, but for rigging one might use constraint
		 * influence to be used to drive some corrective shape keys or so.
		 */
		if (BLI_findindex(&object->constraints, con) != -1) {
			*type = DEG_NODE_TYPE_TRANSFORM;
			*operation_code = DEG_OPCODE_TRANSFORM_LOCAL;
			return true;
		}
		else if (object->pose != NULL) {
			LISTBASE_FOREACH(bPoseChannel *, pchan, &object->pose->chanbase) {
				if (BLI_findindex(&pchan->constraints, con) != -1) {
					*type = DEG_NODE_TYPE_BONE;
					*operation_code = DEG_OPCODE_BONE_LOCAL;
					*subdata = pchan->name;
					return true;
				}
			}
		}
	}
	else if (RNA_struct_is_a(ptr->type, &RNA_Modifier)) {
		*type = DEG_NODE_TYPE_GEOMETRY;
		return true;
	}
	else if (ptr->type == &RNA_Object) {
		/* Transforms props? */
		if (prop != NULL) {
			const char *prop_identifier = RNA_property_identifier((PropertyRNA *)prop);
			/* TODO(sergey): How to optimize this? */
			if (strstr(prop_identifier, "location") ||
			    strstr(prop_identifier, "rotation") ||
			    strstr(prop_identifier, "scale") ||
			    strstr(prop_identifier, "matrix_"))
			{
				*type = DEG_NODE_TYPE_TRANSFORM;
				return true;
			}
			else if (strstr(prop_identifier, "data")) {
				/* We access object.data, most likely a geometry.
				 * Might be a bone tho..
				 */
				*type = DEG_NODE_TYPE_GEOMETRY;
				return true;
			}
		}
	}
	else if (ptr->type == &RNA_ShapeKey) {
		*id = (ID *)ptr->id.data;
		*type = DEG_NODE_TYPE_GEOMETRY;
		return true;
	}
	else if (ptr->type == &RNA_Key) {
		*id = (ID *)ptr->id.data;
		*type = DEG_NODE_TYPE_GEOMETRY;
		return true;
	}
	else if (RNA_struct_is_a(ptr->type, &RNA_Sequence)) {
		Sequence *seq = (Sequence *)ptr->data;
		/* Sequencer strip */
		*type = DEG_NODE_TYPE_SEQUENCER;
		*subdata = seq->name; // xxx?
		return true;
	}
	else if (ptr->type == &RNA_Curve) {
		*id = (ID *)ptr->id.data;
		*type = DEG_NODE_TYPE_GEOMETRY;
		return true;
	}
	if (prop != NULL) {
		/* All unknown data effectively falls under "parameter evaluation". */
		if (RNA_property_is_idprop(prop)) {
			*type = DEG_NODE_TYPE_PARAMETERS;
			*operation_code = DEG_OPCODE_ID_PROPERTY;
			*operation_name = RNA_property_identifier((PropertyRNA *)prop);
			*operation_name_tag = -1;
		}
		else {
			*type = DEG_NODE_TYPE_PARAMETERS;
			*operation_code = DEG_OPCODE_PARAMETERS_EVAL;
			*operation_name = "";
			*operation_name_tag = -1;
		}
		return true;
	}
	return false;
}

/* Convenience wrapper to find node given just pointer + property. */
DepsNode *Depsgraph::find_node_from_pointer(const PointerRNA *ptr,
                                            const PropertyRNA *prop) const
{
	ID *id;
	eDepsNode_Type node_type;
	const char *component_name, *operation_name;
	eDepsOperation_Code operation_code;
	int operation_name_tag;

	if (pointer_to_component_node_criteria(
	                 ptr, prop,
	                 &id, &node_type, &component_name,
	                 &operation_code, &operation_name, &operation_name_tag))
	{
		IDDepsNode *id_node = find_id_node(id);
		if (id_node == NULL) {
			return NULL;
		}
		ComponentDepsNode *comp_node =
		        id_node->find_component(node_type, component_name);
		if (comp_node == NULL) {
			return NULL;
		}
		if (operation_code == DEG_OPCODE_OPERATION) {
			return comp_node;
		}
		return comp_node->find_operation(operation_code,
		                                 operation_name,
		                                 operation_name_tag);
	}
	return NULL;
}

/* Node Management ---------------------------- */

static void id_node_deleter(void *value)
{
	IDDepsNode *id_node = reinterpret_cast<IDDepsNode *>(value);
	OBJECT_GUARDED_DELETE(id_node, IDDepsNode);
}

TimeSourceDepsNode *Depsgraph::add_time_source()
{
	if (time_source == NULL) {
		DepsNodeFactory *factory = deg_type_get_factory(DEG_NODE_TYPE_TIMESOURCE);
		time_source = (TimeSourceDepsNode *)factory->create_node(NULL, "", "Time Source");
	}
	return time_source;
}

TimeSourceDepsNode *Depsgraph::find_time_source() const
{
	return time_source;
}

IDDepsNode *Depsgraph::find_id_node(const ID *id) const
{
	return reinterpret_cast<IDDepsNode *>(BLI_ghash_lookup(id_hash, id));
}

IDDepsNode *Depsgraph::add_id_node(ID *id, const char *name)
{
	IDDepsNode *id_node = find_id_node(id);
	if (!id_node) {
		DepsNodeFactory *factory = deg_type_get_factory(DEG_NODE_TYPE_ID_REF);
		id_node = (IDDepsNode *)factory->create_node(id, "", name);
		/* register */
		BLI_ghash_insert(id_hash, id, id_node);
		id_nodes.push_back(id_node);
	}
	return id_node;
}

void Depsgraph::clear_id_nodes()
{
	BLI_ghash_clear(id_hash, NULL, id_node_deleter);
	id_nodes.clear();
}

/* Add new relationship between two nodes. */
DepsRelation *Depsgraph::add_new_relation(OperationDepsNode *from,
                                          OperationDepsNode *to,
                                          const char *description,
                                          bool check_unique)
{
	DepsRelation *rel = NULL;
	if (check_unique) {
		rel = check_nodes_connected(from, to, description);
	}
	if (rel != NULL) {
		return rel;
	}
	/* Create new relation, and add it to the graph. */
	rel = OBJECT_GUARDED_NEW(DepsRelation, from, to, description);
	/* TODO(sergey): Find a better place for this. */
#ifdef WITH_OPENSUBDIV
	ComponentDepsNode *comp_node = from->owner;
	if (comp_node->type == DEG_NODE_TYPE_GEOMETRY) {
		IDDepsNode *id_to = to->owner->owner;
		IDDepsNode *id_from = from->owner->owner;
		if (id_to != id_from && (id_to->id->recalc & ID_RECALC_ALL)) {
			if ((id_from->eval_flags & DAG_EVAL_NEED_CPU) == 0) {
				id_from->tag_update(this);
				id_from->eval_flags |= DAG_EVAL_NEED_CPU;
			}
		}
	}
#endif
	return rel;
}

/* Add new relation between two nodes */
DepsRelation *Depsgraph::add_new_relation(DepsNode *from, DepsNode *to,
                                          const char *description,
                                          bool check_unique)
{
	DepsRelation *rel = NULL;
	if (check_unique) {
		rel = check_nodes_connected(from, to, description);
	}
	if (rel != NULL) {
		return rel;
	}
	/* Create new relation, and add it to the graph. */
	rel = OBJECT_GUARDED_NEW(DepsRelation, from, to, description);
	return rel;
}

DepsRelation *Depsgraph::check_nodes_connected(const DepsNode *from,
                                               const DepsNode *to,
                                               const char *description)
{
	foreach (DepsRelation *rel, from->outlinks) {
		BLI_assert(rel->from == from);
		if (rel->to != to) {
			continue;
		}
		if (description != NULL && !STREQ(rel->name, description)) {
			continue;
		}
		return rel;
	}
	return NULL;
}

/* ************************ */
/* Relationships Management */

DepsRelation::DepsRelation(DepsNode *from,
                           DepsNode *to,
                           const char *description)
  : from(from),
    to(to),
    name(description),
    flag(0)
{
	/* Hook it up to the nodes which use it.
	 *
	 * NOTE: We register relation in the nodes which this link connects to here
	 * in constructor but we don't unregister it in the destructor.
	 *
	 * Reasoning:
	 *
	 * - Destructor is currently used on global graph destruction, so there's no
	 *   real need in avoiding dangling pointers, all the memory is to be freed
	 *   anyway.
	 *
	 * - Unregistering relation is not a cheap operation, so better to have it
	 *   as an explicit call if we need this.
	 */
	from->outlinks.push_back(this);
	to->inlinks.push_back(this);
}

DepsRelation::~DepsRelation()
{
	/* Sanity check. */
	BLI_assert(from != NULL && to != NULL);
}

void DepsRelation::unlink()
{
	/* Sanity check. */
	BLI_assert(from != NULL && to != NULL);
	remove_from_vector(&from->outlinks, this);
	remove_from_vector(&to->inlinks, this);
}

/* Low level tagging -------------------------------------- */

/* Tag a specific node as needing updates. */
void Depsgraph::add_entry_tag(OperationDepsNode *node)
{
	/* Sanity check. */
	if (!node)
		return;

	/* Add to graph-level set of directly modified nodes to start searching from.
	 * NOTE: this is necessary since we have several thousand nodes to play with...
	 */
	BLI_gset_insert(entry_tags, node);
}

void Depsgraph::clear_all_nodes()
{
	clear_id_nodes();
	if (time_source != NULL) {
		OBJECT_GUARDED_DELETE(time_source, TimeSourceDepsNode);
		time_source = NULL;
	}
}

void deg_editors_id_update(Main *bmain, ID *id)
{
	if (deg_editor_update_id_cb != NULL) {
		deg_editor_update_id_cb(bmain, id);
	}
}

void deg_editors_scene_update(Main *bmain, Scene *scene, bool updated)
{
	if (deg_editor_update_scene_cb != NULL) {
		deg_editor_update_scene_cb(bmain, scene, updated);
	}
}

bool deg_terminal_do_color(void)
{
	return (G.debug & G_DEBUG_DEPSGRAPH_PRETTY) != 0;
}

string deg_color_for_pointer(const void *pointer)
{
	if (!deg_terminal_do_color()) {
		return "";
	}
	int r, g, b;
	BLI_hash_pointer_to_color(pointer, &r, &g, &b);
	char buffer[64];
	BLI_snprintf(buffer, sizeof(buffer), TRUECOLOR_ANSI_COLOR_FORMAT, r, g, b);
	return string(buffer);
}

string deg_color_end(void)
{
	if (!deg_terminal_do_color()) {
		return "";
	}
	return string(TRUECOLOR_ANSI_COLOR_FINISH);
}

}  // namespace DEG

/* **************** */
/* Public Graph API */

/* Initialize a new Depsgraph */
Depsgraph *DEG_graph_new()
{
	DEG::Depsgraph *deg_depsgraph = OBJECT_GUARDED_NEW(DEG::Depsgraph);
	return reinterpret_cast<Depsgraph *>(deg_depsgraph);
}

/* Free graph's contents and graph itself */
void DEG_graph_free(Depsgraph *graph)
{
	using DEG::Depsgraph;
	DEG::Depsgraph *deg_depsgraph = reinterpret_cast<DEG::Depsgraph *>(graph);
	OBJECT_GUARDED_DELETE(deg_depsgraph, Depsgraph);
}

/* Set callbacks which are being called when depsgraph changes. */
void DEG_editors_set_update_cb(DEG_EditorUpdateIDCb id_func,
                               DEG_EditorUpdateSceneCb scene_func,
                               DEG_EditorUpdateScenePreCb scene_pre_func)
{
	DEG::deg_editor_update_id_cb = id_func;
	DEG::deg_editor_update_scene_cb = scene_func;
	DEG::deg_editor_update_scene_pre_cb = scene_pre_func;
}

void DEG_editors_update_pre(Main *bmain, Scene *scene, bool time)
{
	if (DEG::deg_editor_update_scene_pre_cb != NULL) {
		DEG::deg_editor_update_scene_pre_cb(bmain, scene, time);
	}
}

/* Evaluation and debug */

void DEG_debug_print_eval(const char *function_name,
                          const char *object_name,
                          const void *object_address)
{
	if ((G.debug & G_DEBUG_DEPSGRAPH_EVAL) == 0) {
		return;
	}
	fprintf(stdout,
	        "%s on %s %s(%p)%s\n",
	        function_name,
	        object_name,
	        DEG::deg_color_for_pointer(object_address).c_str(),
	        object_address,
	        DEG::deg_color_end().c_str());
	fflush(stdout);
}

void DEG_debug_print_eval_subdata(const char *function_name,
                                  const char *object_name,
                                  const void *object_address,
                                  const char *subdata_comment,
                                  const char *subdata_name,
                                  const void *subdata_address)
{
	if ((G.debug & G_DEBUG_DEPSGRAPH_EVAL) == 0) {
		return;
	}
	fprintf(stdout,
	        "%s on %s %s(%p)%s %s %s %s(%p)%s\n",
	        function_name,
	        object_name,
	        DEG::deg_color_for_pointer(object_address).c_str(),
	        object_address,
	        DEG::deg_color_end().c_str(),
	        subdata_comment,
	        subdata_name,
	        DEG::deg_color_for_pointer(subdata_address).c_str(),
	        subdata_address,
	        DEG::deg_color_end().c_str());
	fflush(stdout);
}

void DEG_debug_print_eval_subdata_index(const char *function_name,
                                        const char *object_name,
                                        const void *object_address,
                                        const char *subdata_comment,
                                        const char *subdata_name,
                                        const void *subdata_address,
                                        const int subdata_index)
{
	if ((G.debug & G_DEBUG_DEPSGRAPH_EVAL) == 0) {
		return;
	}
	fprintf(stdout,
	        "%s on %s %s(%p)^%s %s %s[%d] %s(%p)%s\n",
	        function_name,
	        object_name,
	        DEG::deg_color_for_pointer(object_address).c_str(),
	        object_address,
	        DEG::deg_color_end().c_str(),
	        subdata_comment,
	        subdata_name,
	        subdata_index,
	        DEG::deg_color_for_pointer(subdata_address).c_str(),
	        subdata_address,
	        DEG::deg_color_end().c_str());
	fflush(stdout);
}

void DEG_debug_print_eval_time(const char *function_name,
                               const char *object_name,
                               const void *object_address,
                               float time)
{
	if ((G.debug & G_DEBUG_DEPSGRAPH_EVAL) == 0) {
		return;
	}
	fprintf(stdout,
	        "%s on %s %s(%p)%s at time %f\n",
	        function_name,
	        object_name,
	        DEG::deg_color_for_pointer(object_address).c_str(),
	        object_address,
	        DEG::deg_color_end().c_str(),
	        time);
	fflush(stdout);
}