/**
 * Copyright (c) 2026 Dominic Masters
 *
 * This software is released under the MIT License.
 * https://opensource.org/licenses/MIT
 */

#pragma once
#include "error/error.h"
#include "save/savefile.h"
#include <pspiofilemgr.h>
#include <psputility.h>

#define SAVE_PSP_PATH_MAX 256
#define SAVE_PSP_ROOT "ms0:/"
#define SAVE_PSP_FILE_NAME "save.bin"
#define SAVE_PSP_FILE_FORMAT "ms0:/PSP/SAVEDATA/%s%02u/" SAVE_PSP_FILE_NAME
#define SAVE_PSP_DATA_BUFFER_SIZE 4096

#ifndef SAVE_PSP_GAME_NAME
  #define SAVE_PSP_GAME_NAME "DUSK00001"
#endif

typedef enum {
  SAVE_PSP_OP_NONE,
  SAVE_PSP_OP_SAVE,
  SAVE_PSP_OP_LOAD
} savepspop_t;

typedef struct {
  SceUtilitySavedataParam param;
  // Raw buffer sceUtilitySavedata reads/writes the whole save into/from -
  // populated by our own savestream_t serialization (see savestreampsp.h)
  // before a save starts, and deserialized from after a load finishes.
  uint8_t dataBuffer[SAVE_PSP_DATA_BUFFER_SIZE] __attribute__((aligned(64)));
  size_t dataLength;

  savepspop_t op;
  // True once sceUtilitySavedataShutdownStart() has been requested (dialog
  // status PSP_UTILITY_DIALOG_QUIT seen) - distinguishes a normal "torn
  // down after finishing" NONE/FINISHED from a genuinely unexpected one
  // seen before ever reaching QUIT. Some implementations (confirmed on
  // PPSSPP) settle straight to NONE after shutdown without a separately
  // observable FINISHED step in between.
  bool_t shuttingDown;
  uint8_t slot;
  savecallback_t onComplete;
  void *onCompleteUser;
} savepsp_t;

/**
 * Initializes the save system on PSP. Confirms the memory stick is
 * actually reachable (sceIoGetstat on SAVE_PSP_ROOT) rather than assuming
 * so, since the savedata dialog otherwise only reports failure once a
 * save/load is actually attempted.
 *
 * @return An error code if no memory stick is reachable.
 */
errorret_t saveInitPSP(void);

/**
 * Disposes of the save system on PSP.
 *
 * @return An error code if disposal fails.
 */
errorret_t saveDisposePSP(void);

/**
 * Deletes the save data folder for the given slot from the memory stick.
 *
 * @param slot The save slot index.
 * @return An error code if the delete fails.
 */
errorret_t saveDeletePSP(const uint8_t slot);

/**
 * Starts a save via the native sceUtilitySavedata dialog (mode AUTOSAVE -
 * writes silently with just a brief icon flash, no confirm screen, since
 * SAVE mode shows one even for a slot with no existing data - but
 * PARAM.SFO/title/description are generated identically regardless of
 * mode, and the OS handles the save browser entry either way) for the
 * given slot. Serializes SAVE.files[slot] into SAVE.platform.dataBuffer
 * first, synchronously, then kicks off the dialog and returns - completion
 * is reported later via onComplete, driven by savePSPUpdate() each frame.
 * If no save data exists yet for this slot, sceUtilitySavedataInitStart()
 * creates it.
 *
 * @param slot The save slot index.
 * @param onComplete Callback invoked once the dialog finishes.
 * @param user User data passed through to onComplete.
 */
void savePSPBeginSave(
  const uint8_t slot, savecallback_t onComplete, void *user
);

/**
 * Starts a load via the native sceUtilitySavedata dialog (mode AUTOLOAD -
 * see savePSPBeginSave() for why not the plain LOAD mode) for the given
 * slot, unless a quick sceIoGetstat check finds no save data for this slot
 * yet - in which case onComplete is invoked immediately with
 * SAVE.files[slot].exists left false, matching the other platforms'
 * "no file yet" semantics, and no dialog is shown at all.
 *
 * @param slot The save slot index.
 * @param onComplete Callback invoked once the dialog (or immediate
 *   not-found short-circuit) finishes.
 * @param user User data passed through to onComplete.
 */
void savePSPBeginLoad(
  const uint8_t slot, savecallback_t onComplete, void *user
);

/**
 * Pumps the in-progress save/load dialog one step, if any - must be called
 * every engine frame (see saveUpdate()). No-op if no dialog is active.
 *
 * @return An error code indicating success or failure.
 */
errorret_t savePSPUpdate(void);

/**
 * True while a save/load dialog is in progress (see savePSPBeginSave()/
 * savePSPBeginLoad()).
 *
 * @return True if a save/load dialog is currently open.
 */
bool_t savePSPIsBusy(void);