/*
 * 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.
 */

/** \file
 * \ingroup depsgraph
 */

#pragma once

#include "BLI_ghash.h"
#include "BLI_sys_types.h"
#include "DNA_ID.h"
#include "intern/node/deg_node.h"

namespace blender {
namespace deg {

struct ComponentNode;

typedef uint64_t IDComponentsMask;

/* NOTE: We use max comparison to mark an id node that is linked more than once
 * So keep this enum ordered accordingly. */
enum eDepsNode_LinkedState_Type {
  /* Generic indirectly linked id node. */
  DEG_ID_LINKED_INDIRECTLY = 0,
  /* Id node present in the set (background) only. */
  DEG_ID_LINKED_VIA_SET = 1,
  /* Id node directly linked via the SceneLayer. */
  DEG_ID_LINKED_DIRECTLY = 2,
};
const char *linkedStateAsString(eDepsNode_LinkedState_Type linked_state);

/* ID-Block Reference */
struct IDNode : public Node {
  struct ComponentIDKey {
    ComponentIDKey(NodeType type, const char *name = "");
    uint64_t hash() const;
    bool operator==(const ComponentIDKey &other) const;

    NodeType type;
    const char *name;
  };

  /** Initialize 'id' node - from pointer data given. */
  virtual void init(const ID *id, const char *subdata) override;
  void init_copy_on_write(ID *id_cow_hint = nullptr);
  ~IDNode();
  void destroy();

  virtual string identifier() const override;

  ComponentNode *find_component(NodeType type, const char *name = "") const;
  ComponentNode *add_component(NodeType type, const char *name = "");

  virtual void tag_update(Depsgraph *graph, eUpdateSource source) override;

  void finalize_build(Depsgraph *graph);

  IDComponentsMask get_visible_components_mask() const;

  /* Type of the ID stored separately, so it's possible to perform check whether CoW is needed
   * without de-referencing the id_cow (which is not safe when ID is NOT covered by CoW and has
   * been deleted from the main database.) */
  ID_Type id_type;

  /* ID Block referenced. */
  ID *id_orig;

  /* Session-wide UUID of the id_orig.
   * Is used on relations update to map evaluated state from old nodes to the new ones, without
   * relying on pointers (which are not guaranteed to be unique) and without dereferencing id_orig
   * which could be "stale" pointer. */
  uint id_orig_session_uuid;

  /* Evaluated data-block.
   * Will be covered by the copy-on-write system if the ID Type needs it. */
  ID *id_cow;

  /* Hash to make it faster to look up components. */
  Map<ComponentIDKey, ComponentNode *> components;

  /* Additional flags needed for scene evaluation.
   * TODO(sergey): Only needed for until really granular updates
   * of all the entities. */
  uint32_t eval_flags;
  uint32_t previous_eval_flags;

  /* Extra customdata mask which needs to be evaluated for the mesh object. */
  DEGCustomDataMeshMasks customdata_masks;
  DEGCustomDataMeshMasks previous_customdata_masks;

  eDepsNode_LinkedState_Type linked_state;

  /* Indicates the data-block is visible in the evaluated scene. */
  bool is_directly_visible;

  /* For the collection type of ID, denotes whether collection was fully
   * recursed into. */
  bool is_collection_fully_expanded;

  /* Is used to figure out whether object came to the dependency graph via a base. */
  bool has_base;

  /* Accumulated flag from operation. Is initialized and used during updates flush. */
  bool is_user_modified;

  /* Copy-on-Write component has been explicitly tagged for update. */
  bool is_cow_explicitly_tagged;

  /* Accumulate recalc flags from multiple update passes. */
  int id_cow_recalc_backup;

  IDComponentsMask visible_components_mask;
  IDComponentsMask previously_visible_components_mask;

  DEG_DEPSNODE_DECLARE;
};

}  // namespace deg
}  // namespace blender