#include "components/fs/FS.h"
#include <cstring>
#include <littlefs/lfs.h>
#include <lvgl/lvgl.h>

using namespace Pinetime::Controllers;

FS::FS(Pinetime::Drivers::SpiNorFlash& driver)
  : flashDriver {driver},
    lfsConfig {
      .context = this,
      .read = SectorRead,
      .prog = SectorProg,
      .erase = SectorErase,
      .sync = SectorSync,

      .read_size = 16,
      .prog_size = 8,
      .block_size = blockSize,
      .block_count = size / blockSize,
      .block_cycles = 1000u,

      .cache_size = 16,
      .lookahead_size = 16,

      .name_max = 50,
      .attr_max = 50,
    } {
}

void FS::Init() {

  // try mount
  int err = lfs_mount(&lfs, &lfsConfig);

  // reformat if we can't mount the filesystem
  // this should only happen on the first boot
  if (err != LFS_ERR_OK) {
    lfs_format(&lfs, &lfsConfig);
    err = lfs_mount(&lfs, &lfsConfig);
    if (err != LFS_ERR_OK) {
      return;
    }
  }

#ifndef PINETIME_IS_RECOVERY
  VerifyResource();
  LVGLFileSystemInit();
#endif
}

void FS::VerifyResource() {
  // validate the resource metadata
  resourcesValid = true;
}

int FS::FileOpen(lfs_file_t* file_p, const char* fileName, const int flags) {
  return lfs_file_open(&lfs, file_p, fileName, flags);
}

int FS::FileClose(lfs_file_t* file_p) {
  return lfs_file_close(&lfs, file_p);
}

int FS::FileRead(lfs_file_t* file_p, uint8_t* buff, uint32_t size) {
  return lfs_file_read(&lfs, file_p, buff, size);
}

int FS::FileWrite(lfs_file_t* file_p, const uint8_t* buff, uint32_t size) {
  return lfs_file_write(&lfs, file_p, buff, size);
}

int FS::FileSeek(lfs_file_t* file_p, uint32_t pos) {
  return lfs_file_seek(&lfs, file_p, pos, LFS_SEEK_SET);
}

int FS::FileDelete(const char* fileName) {
  return lfs_remove(&lfs, fileName);
}

int FS::DirOpen(const char* path, lfs_dir_t* lfs_dir) {
  return lfs_dir_open(&lfs, lfs_dir, path);
}

int FS::DirClose(lfs_dir_t* lfs_dir) {
  return lfs_dir_close(&lfs, lfs_dir);
}

int FS::DirRead(lfs_dir_t* dir, lfs_info* info) {
  return lfs_dir_read(&lfs, dir, info);
}
int FS::DirRewind(lfs_dir_t* dir) {
  return lfs_dir_rewind(&lfs, dir);
}
int FS::DirCreate(const char* path) {
  return lfs_mkdir(&lfs, path);
}
int FS::Rename(const char* oldPath, const char* newPath){
  return lfs_rename(&lfs,oldPath,newPath);
}
int FS::Stat(const char* path, lfs_info* info) {
  return lfs_stat(&lfs, path, info);
}
lfs_ssize_t FS::GetFSSize() {
  return lfs_fs_size(&lfs);
}

/*

    ----------- Interface between littlefs and SpiNorFlash -----------

*/
int FS::SectorSync(const struct lfs_config* c) {
  return 0;
}

int FS::SectorErase(const struct lfs_config* c, lfs_block_t block) {
  Pinetime::Controllers::FS& lfs = *(static_cast<Pinetime::Controllers::FS*>(c->context));
  const size_t address = startAddress + (block * blockSize);
  lfs.flashDriver.SectorErase(address);
  return lfs.flashDriver.EraseFailed() ? -1 : 0;
}

int FS::SectorProg(const struct lfs_config* c, lfs_block_t block, lfs_off_t off, const void* buffer, lfs_size_t size) {
  Pinetime::Controllers::FS& lfs = *(static_cast<Pinetime::Controllers::FS*>(c->context));
  const size_t address = startAddress + (block * blockSize) + off;
  lfs.flashDriver.Write(address, (uint8_t*) buffer, size);
  return lfs.flashDriver.ProgramFailed() ? -1 : 0;
}

int FS::SectorRead(const struct lfs_config* c, lfs_block_t block, lfs_off_t off, void* buffer, lfs_size_t size) {
  Pinetime::Controllers::FS& lfs = *(static_cast<Pinetime::Controllers::FS*>(c->context));
  const size_t address = startAddress + (block * blockSize) + off;
  lfs.flashDriver.Read(address, static_cast<uint8_t*>(buffer), size);
  return 0;
}

/*

    ----------- LVGL filesystem integration -----------

*/

namespace {
  lv_fs_res_t lvglOpen(lv_fs_drv_t* drv, void* file_p, const char* path, lv_fs_mode_t mode) {
    lfs_file_t* file = static_cast<lfs_file_t*>(file_p);
    FS* filesys = static_cast<FS*>(drv->user_data);
    int res = filesys->FileOpen(file, path, LFS_O_RDONLY);
    if (res == 0) {
      if (file->type == 0) {
        return LV_FS_RES_FS_ERR;
      } else {
        return LV_FS_RES_OK;
      }
    }
    return LV_FS_RES_NOT_EX;
  }

  lv_fs_res_t lvglClose(lv_fs_drv_t* drv, void* file_p) {
    FS* filesys = static_cast<FS*>(drv->user_data);
    lfs_file_t* file = static_cast<lfs_file_t*>(file_p);
    filesys->FileClose(file);

    return LV_FS_RES_OK;
  }

  lv_fs_res_t lvglRead(lv_fs_drv_t* drv, void* file_p, void* buf, uint32_t btr, uint32_t* br) {
    FS* filesys = static_cast<FS*>(drv->user_data);
    lfs_file_t* file = static_cast<lfs_file_t*>(file_p);
    filesys->FileRead(file, static_cast<uint8_t*>(buf), btr);
    *br = btr;
    return LV_FS_RES_OK;
  }

  lv_fs_res_t lvglSeek(lv_fs_drv_t* drv, void* file_p, uint32_t pos) {
    FS* filesys = static_cast<FS*>(drv->user_data);
    lfs_file_t* file = static_cast<lfs_file_t*>(file_p);
    filesys->FileSeek(file, pos);
    return LV_FS_RES_OK;
  }
}

void FS::LVGLFileSystemInit() {

  lv_fs_drv_t fs_drv;
  lv_fs_drv_init(&fs_drv);

  fs_drv.file_size = sizeof(lfs_file_t);
  fs_drv.letter = 'F';
  fs_drv.open_cb = lvglOpen;
  fs_drv.close_cb = lvglClose;
  fs_drv.read_cb = lvglRead;
  fs_drv.seek_cb = lvglSeek;

  fs_drv.user_data = this;

  lv_fs_drv_register(&fs_drv);
}