module Scan = struct
  (* open Disk
     let execute commit locations (entity: string) =
       let binary = Executor.read commit locations ~filename:("schema~" ^ entity) in
       let relation =
         Result.map_error (fun _ -> "Failed to deserialize relation from binary format.")
         @@ Data_encoding.Binary.of_bytes Schema.Protocol.relation_encoding (Bytes.concat Bytes.empty binary) in
       match relation with
       | Ok relation ->
          begin
            let attrs = List.map (fun (a: Schema.Protocol.attribute) -> relation.name ^ "/" ^ a.name) relation.attributes in
            Executor.read commit locations ~filename:("schema~" ^ entity)
          end
       | Error err -> failwith err *)
end

module Join = struct
  (* open Disk
     let execute (left_attributes: bytes list) (right_attributes: bytes list) locations =
       (* Redundant operations that are already in the locations, but this is easier to implement now *)
       (* Fix this when we persist the indexes *)
       let left_computed_hashes: (int * string) list = List.mapi (fun index elem -> (index, Interop.Sha256.compute_hash elem)) left_attributes in
       let right_computed_hashes: (int * string) list = List.mapi (fun index elem -> (index, Interop.Sha256.compute_hash elem)) right_attributes in
       let references_locations_right = List.filter_map (fun (index, rhash) -> Option.map (fun (elem: Executor.Location.t) -> index, rhash, elem.references)
                                                                               @@ Executor.StringMap.find_opt rhash locations) right_computed_hashes in
       let indexes =
         List.filter_map (fun (lindex, lhash) -> Option.map (fun (rindex, rhash, _) -> lindex, rindex, lhash, rhash)
                                                 @@ List.find_opt (fun (_rindex, _rhash, references) -> List.exists ((=) lhash) references) references_locations_right) left_computed_hashes
       in List.map (fun (lindex, rindex, _, _) -> List.nth left_attributes lindex, List.nth right_attributes rindex) indexes *)

end

module Filter = struct end