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

#pragma once
#include "error/error.h"
#include "util/reflist.h"
#include <zip.h>

#include "asset/type/assetpaletteimage.h"
#include "asset/type/assetalphaimage.h"

#define ASSET_HEADER_SIZE 3
#define ASSET_REFERENCE_COUNT_MAX 8

typedef struct {
  void (*load)();
} assetcallback_t;

typedef enum {
  ASSET_STATE_NOT_LOADED,
  ASSET_STATE_LOADING,
  ASSET_STATE_LOADED,
  ASSET_STATE_ERROR,
} assetstate_t;

typedef enum {
  ASSET_TYPE_UNKNOWN,
  ASSET_TYPE_PALETTE_IMAGE,
  ASSET_TYPE_ALPHA_IMAGE,

  ASSET_TYPE_COUNT
} assettype_t;

typedef struct asset_s {
  char_t filename[FILENAME_MAX];
  ref_t refListArray[ASSET_REFERENCE_COUNT_MAX];
  reflist_t refList;
  assetstate_t state;
  assettype_t type;
  zip_file_t *file;

  union {
    assetpaletteimage_t paletteImage;
    assetalphaimage_t alphaImage;
  };
} asset_t;

typedef struct {
  const char_t header[ASSET_HEADER_SIZE + 1];
  errorret_t (*load)(asset_t *asset);
  errorret_t (*dispose)(asset_t *asset);
} assetdef_t;

extern assetdef_t ASSET_DEFINITIONS[ASSET_TYPE_COUNT];

/**
 * Initializes an asset structure. This should be called by the asset manager
 * only.
 * 
 * @param asset The asset structure to initialize.
 * @param filename The filename of the asset.
 * @return An error code.
 */
errorret_t assetInit(asset_t *asset, const char_t *filename);

/**
 * Requests a lock on the given asset. This will increase the reference count
 * of the asset, and prevent it from being unloaded until all locks are
 * released.
 * 
 * @param asset The asset to lock.
 * @return A unique reference ID for the lock.
 */
ref_t assetLock(asset_t *asset);

/**
 * Releases a lock on the given asset. This will decrease the reference count
 * of the asset, and allow it to be unloaded if there are no more locks.
 * 
 * @param asset The asset to unlock.
 * @param ref The reference ID of the lock to release.
 */
void assetUnlock(asset_t *asset, const ref_t ref);

/**
 * Permission has been granted to load the asset data from disk. This should
 * only be called by the asset manager.
 * 
 * @param asset The asset to load.
 * @return An error code.
 */
errorret_t assetLoad(asset_t *asset);

/**
 * Disposes of the asset, freeing any allocated memory and closing any open
 * file handles. This should only be called by the asset manager.
 * 
 * @param asset The asset to dispose of.
 */
errorret_t assetDispose(asset_t *asset);