fetch-torrent.nix

{ pkgs ? import <nixpkgs> {} }:
{ url, sha256 }:
pkgs.runCommand
  (pkgs.lib.strings.removeSuffix ".torrent" (builtins.baseNameOf url))
  {
    buildInputs = [ pkgs.transmission pkgs.procps ];
    outputHashMode = "flat";
    outputHashAlgo = "sha256";
    outputHash = sha256;
  }
  ''
    HOME=$(pwd)

    echo "#!/bin/sh" > script
    echo "pkill transmission" >> script
    chmod +x ./script

    mkdir ./results

    transmission-cli \
      --no-portmap \
      --finish "$(pwd)/script" \
      --download-dir ./results \
       '${url}' \
     || true

    mv ./results/* $out
  ''