/**
 * Copyright (c) 2025 Dominic Masters
 * 
 * This software is released under the MIT License.
 * https://opensource.org/licenses/MIT
 */

#pragma once
#include "ecs/ecsentity.h"

#define SCENE_ITEM_CHILD_MAX 16

typedef struct {
  ecsid_t children[SCENE_ITEM_CHILD_MAX];
  uint8_t childCount;
  ecsid_t parent;
} scenetreenode_t;

typedef struct scene_s {
  scenetreenode_t items[ECS_ENTITY_COUNT_MAX];
} scenetree_t;

extern scenetree_t SCENE_TREE;

/**
 * Initialize the scene tree.
 * 
 * This will initialize the ECS system and prepare the scene tree for use.
 */
void sceneTreeInit(void);

/**
 * Create a new scene item in the scene tree.
 * This will create a new entity in the ECS and return its ID.
 * 
 * @return The ID of the newly created scene item.
 */
ecsid_t sceneTreeCreate(void);

/**
 * Get the parent of a given scene item.
 * 
 * @param id The ID of the scene item.
 * @return The ID of the parent scene item, or -1 if it has no parent.
 */
ecsid_t sceneTreeParentGet(const ecsid_t child);

/**
 * Get the children of a given scene item. If children is NULL only the count
 * will be returned.
 * 
 * @param id The ID of the scene item.
 * @param children Pointer to an array where the children IDs will be stored.
 * @return The number of children found.
 */
uint8_t sceneTreeChildGetAll(const ecsid_t id, ecsid_t *children);

/**
 * Add a child to a parent in the scene tree.
 * 
 * @param parent The ID of the parent scene item.
 * @param child The ID of the child scene item to add.
 */
void sceneTreeChildAdd(const ecsid_t parent, const ecsid_t child);

/**
 * Remove a child from a parent in the scene tree.
 * 
 * @param prnt The ID of the parent scene item.
 * @param child The ID of the child scene item to remove.
 */
void sceneTreeChildRemove(const ecsid_t prnt, const ecsid_t child);

/**
 * Remove all children from a parent in the scene tree.
 * 
 * @param parent The ID of the parent scene item.
 */
void sceneTreeChildRemoveAll(const ecsid_t parent);

/**
 * Returns true if the child is within the parent's children, recursively.
 * 
 * @param parent The ID of the parent scene item.
 * @param child The ID of the child scene item to check.
 * @return True if the child is in the parent's children, false otherwise.
 */
bool_t sceneTreeChildInTree(const ecsid_t parent, const ecsid_t child);