#include "fs.hpp"
#include <assert.h>

Fs::Fs(RawDisk *disk, bool load, uint64_t user_inode_blocks) : disk(disk) {
  superblock = SuperBlock_Data();
  // Determine the num inode blocks
  uint64_t num_inode_blocks = 0; // The superblock is not loaded from disk here; it is done in FilesOperation::initialize called by fischl_init
  if(load) {
    load_superblock();
    num_inode_blocks = superblock.num_inode_blocks;
  } else {
    num_inode_blocks = user_inode_blocks;
    superblock.num_inode_blocks = num_inode_blocks;
    superblock.num_used_inodes = 0;
    superblock.num_data_blocks = disk->diskSize / IO_BLOCK_SIZE - 1 - num_inode_blocks;
    superblock.num_used_data_blocks = 0;
  }
  assert((disk->diskSize / IO_BLOCK_SIZE) >
         2 + num_inode_blocks + DATABLOCKS_PER_BITMAP_BLOCK);
  inode_manager = new INode_Manager_Freelist(this, 1, 1 + num_inode_blocks);
  datablock_manager = new DataBlock_Manager_Bitmap(
      this, 1 + num_inode_blocks, disk->diskSize / IO_BLOCK_SIZE);
};

Fs::~Fs() {
  delete inode_manager;
  delete datablock_manager;
};

int Fs::format() {
  int err;
  if ((err = save_superblock()) < 0)
    return err;
  if ((err = inode_manager->format()) < 0)
    return err;
  if ((err = datablock_manager->format()) < 0)
    return err;
  return 0;
}

int Fs::load_superblock() {
  char buf[IO_BLOCK_SIZE];
  int err;

  if ((err = disk->read_block(0, buf)) < 0)
    return err;

  superblock.deserialize(buf);

  return 0;
}
int Fs::save_superblock() {
  char buf[IO_BLOCK_SIZE] = {0};
  int err;

  superblock.serialize(buf);

  if ((err = disk->write_block(0, buf)) < 0)
    return err;

  return 0;
}

int Fs::save_free_list_head(u_int64_t new_free_list_head) {
  u_int64_t temp = superblock.free_list_head;
  int err;
  superblock.free_list_head = new_free_list_head;
  if ((err = save_superblock()) < 0) {
    superblock.free_list_head = temp;
    return err;
  }
  return 0;
}
int Fs::save_inode_list_head(u_int64_t new_inode_list_head) {
  u_int64_t temp = superblock.inode_list_head;
  int err;
  superblock.inode_list_head = new_inode_list_head;
  if ((err = save_superblock()) < 0) {
    superblock.inode_list_head = temp;
    return err;
  }
  return 0;
}

void Fs::update_num_used_inodes(int delta) {
  superblock.num_used_inodes += delta;
}

void Fs::update_num_used_datablocks(int delta) {
  superblock.num_used_data_blocks += delta;
}