#pragma message "using readdir"

#include "error.hpp"
#include "fs_closedir.hpp"
#include "fs_inode.hpp"
#include "fs_opendir.hpp"
#include "fs_readdir.hpp"
#include "hashset.hpp"
#include "scope_guard.hpp"
#include "ugid.hpp"

#include "fuse_dirents.hpp"


struct DirRV
{
  const fs::path *branch_path;
  DIR *dir;
  int  err;
};

static
uint64_t
_dirent_exact_namelen(const struct dirent *d_)
{
#ifdef _D_EXACT_NAMLEN
  return _D_EXACT_NAMLEN(d_);
#elif defined _DIRENT_HAVE_D_NAMLEN
  return d_->d_namlen;
#else
  return strlen(d_->d_name);
#endif
}

static
inline
std::vector<std::future<DirRV>>
_opendir(ThreadPool          &tp_,
         const Branches::Ptr &branches_,
         const fs::path      &rel_dirpath_,
         uid_t const          uid_,
         gid_t const          gid_)
{
  std::vector<std::future<DirRV>> futures;

  futures.reserve(branches_->size());

  for(const auto &branch : *branches_)
    {
      auto func =
        [&branch,&rel_dirpath_,uid_,gid_]()
        {
          DIR *dir;
          fs::path abs_dirpath;
          const ugid::Set ugid(uid_,gid_);

          abs_dirpath = branch.path / rel_dirpath_;

          errno = 0;
          dir = fs::opendir(abs_dirpath);

          return DirRV{&branch.path,dir,-errno};
        };

      auto rv = tp_.enqueue_task(std::move(func));

      futures.emplace_back(std::move(rv));
    }

  return futures;
}

static
inline
int
_readdir(std::vector<std::future<DirRV>> &dh_futures_,
         const fs::path                  &rel_dirpath_,
         fuse_dirents_t                  *dirents_)
{
  Err err;
  HashSet names;
  fs::path rel_filepath;

  rel_filepath = rel_dirpath_ / "dummy";
  for(auto &dh_future : dh_futures_)
    {
      DirRV dirrv;

      dirrv = dh_future.get();

      err = dirrv.err;
      if(dirrv.dir == NULL)
        continue;
      DEFER { fs::closedir(dirrv.dir); };

      for(dirent *de = fs::readdir(dirrv.dir);
          de;
          de = fs::readdir(dirrv.dir))
        {
          int rv;
          int namelen;

          namelen = ::_dirent_exact_namelen(de);

          rv = names.put(de->d_name,namelen);
          if(rv == 0)
            continue;

          rel_filepath.replace_filename(de->d_name);

          de->d_ino = fs::inode::calc(*dirrv.branch_path,
                                      rel_filepath,
                                      DTTOIF(de->d_type),
                                      de->d_ino);

          fuse_dirents_add(dirents_,de,namelen);
        }
    }

  return err;
}