wip conda multiplatform derivation

conda-multiplatform.nix

# Rename this if it works. Good candidate for extraction to a separate library.
# TODO: document reasoning
{ minicondaVersion ? "4.5.12"
, minicondaSha256 ?
    if stdenv.isDarwin
      then "8ebb463ddf46dd003616b2f6b678403a708e2c54dcc58e212bd35e257761912c"
      else "e5e5b4cd2a918e0e96b395534222773f7241dc59d776db1b9f7fedfcb489157a"
, fetchurl
, stdenv
, bash
, file
#TODO: these are likely to not work on mac
, xorg
, libselinux
, condaDeps ? [ stdenv.cc xorg.libSM xorg.libICE xorg.libXrender libselinux ]
}:
let
  src = fetchurl {
    url =
      if stdenv.isDarwin
        then "https://repo.continuum.io/miniconda/Miniconda3-${minicondaVersion}-MacOSX-x86_64.sh"
        else "https://repo.continuum.io/miniconda/Miniconda3-${minicondaVersion}-Linux-x86_64.sh";
    sha256 = minicondaSha256;
  };
in
  #TODO: what if we did what the original did without the shell?
  # TODO: debugging guide here: https://nixos.wiki/wiki/Nixpkgs/Create_and_debug_packages
  stdenv.mkDerivation {
    name = "conda";
    src = src;
    buildInputs = [
      bash
      file
    ] ++ condaDeps;
    unpackPhase = "true";
    # buildPhase
    buildPhase = "true";
    #TODO: we're not producing an $out/bin, the bin is in $out/.conda
    #TODO: drop -xs?
    #TODO: drop debugging
    #TODO: AHA, sandboxing is preventing us from seeing those paths, i think i need a build phase to set the prefix to the build dir, then in install, move that artifact to $out
    installPhase = ''
    set -x
    cp $src ./install
    chmod +x ./install
    bash -x install -p $out -b -f
    '';
  }