module Octal = Octal
module Tar = Tar



let (root, tar_ch) = Tar.parse_tar "asd.tar"
let () = Tar.print_tree "" root

let getattr path =
  match Tar.find path root with
  | None -> raise (Unix.Unix_error (Unix.ENOENT, "hi1", "hi1"))
  | Some (File (_, md)) -> md
  | Some (Directory (_, md)) -> md
  | Some (InferredDirectory (_, md)) -> md

let readdir path _ =
  match Tar.find path root with
  | None -> raise (Unix.Unix_error (Unix.ENOENT, "234", "234"))
  | Some (File (_, _)) -> raise (Unix.Unix_error (Unix.ENOENT, "345", "345"))
  | Some (InferredDirectory (children, _))
  | Some (Directory (children, _)) ->
     ["."; ".."] @ (List.map (fun (name, _) -> name) (Tar.NameMap.to_list children))

(* There seems to be a bug here - the amount argument given to this function
   is NOT the correct requested amount. The buffer size is correct though
   so I'm taking that as the source of truth.
 *)
let read path buf offset _amount =
(*
  let () = Printf.printf "PARAMS %d %d %d\n" (Int64.to_int offset) amount (Bigarray.Array1.dim buf) in
  let () = Out_channel.flush_all () in*)
  match Tar.find path root with
  | None -> raise (Unix.Unix_error (Unix.ENOENT, "read", path))
  | Some (File (fo, md)) ->
     (let (file_buf,read) = (Tar.read_file (File (fo, md)) tar_ch offset (Bigarray.Array1.dim buf)) in
      Bytes.iteri (fun i c -> Bigarray.Array1.set buf i c) file_buf;
     read)
  | _ -> raise (Unix.Unix_error (Unix.EISDIR, "read", path))
 
let _ =
  Fuse.main Sys.argv
    {
      Fuse.default_operations with
      getattr = getattr;
      readdir = readdir;
      read = read;
    }