#pragma message "using getdents"

#include "fs_inode.hpp"
#include "fs_getdents64.hpp"
#include "hashset.hpp"
#include "branches.hpp"
#include "error.hpp"
#include "fs_close.hpp"
#include "fs_open.hpp"
#include "fs_path.hpp"
#include "ugid.hpp"
#include "scope_guard.hpp"

#include "fuse_msgbuf.hpp"
#include "fuse_dirents.hpp"

#include <dirent.h>


struct DirRV
{
  const fs::path *branch_path;
  int fd;
};

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_]()
        {
          int fd;
          fs::path abs_dirpath;
          const ugid::Set ugid(uid_,gid_);

          abs_dirpath = branch.path / rel_dirpath_;

          fd = fs::open_dir_ro(abs_dirpath);

          return DirRV{&branch.path,fd};
        };

      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;
  fuse_msgbuf_t *buf;

  buf = msgbuf_alloc();
  DEFER { msgbuf_free(buf); };

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

      dirrv = dh_future.get();

      err = dirrv.fd;
      if(dirrv.fd < 0)
        continue;
      DEFER { fs::close(dirrv.fd); };

      while(true)
        {
          ssize_t nread;

          nread = fs::getdents64(dirrv.fd,buf->mem,buf->size);
          if(nread <= 0)
            break;

          for(ssize_t pos = 0; pos < nread;)
            {
              int rv;
              int namelen;
              fs::dirent64 *d = reinterpret_cast<fs::dirent64*>(&buf->mem[pos]);

              pos += d->reclen;

              namelen = d->namelen();

              rv = names.put(d->name,namelen);
              if(rv == 0)
                continue;

              rel_filepath.replace_filename(d->name);

              d->ino = fs::inode::calc(*dirrv.branch_path,
                                       rel_filepath,
                                       DTTOIF(d->type),
                                       d->ino);

              fuse_dirents_add(dirents_,d,namelen);
            }
        }
    }

  return err;
}