with import ./pynixify/nixpkgs.nix { };
let
  version = builtins.head (builtins.match ".*'([0-9]+.[0-9]+(.[0-9]+)?)'.*"
    (builtins.readFile ./faraday/__init__.py));

  pynixifyCommand = ''
    pynixify --nixpkgs https://github.com/infobyte/nixpkgs/archive/98720fe237de55ca5779af5ee07407d0947b8deb.tar.gz --local faradaysec --tests faradaysec
  '';

in { dockerName ? "registry.gitlab.com/faradaysec/faraday", dockerTag ? version
, systemUser ? "faraday", systemGroup ? "faraday", systemHome ? null
, port ? 5985, websocketPort ? 9000, bindAddress ? "localhost"

  # If true, will ignore the contents of the last commit as source, ignoring
  # uncommited changes. Recommended to improve reproducibility
, useLastCommit ? true }: rec {

  faraday-server = python38.pkgs.faradaysec.overrideAttrs (old:
    assert !builtins.hasAttr "checkInputs" old; {
      name = "faraday-server-${version}";
      doCheck = true;
      checkPhase = "true";
      checkInputs = [ pynixify runPynixify ];
    } // lib.optionalAttrs useLastCommit {
      src = builtins.fetchGit {
        url = ./.;
        ref = "HEAD";
      };
    });

  dockerImage = dockerTools.buildImage {
    name = dockerName;
    tag = dockerTag;
    created = "now";
    fromImage = null;
    contents = [ faraday-server bash gnused coreutils ];
    config = {
      Cmd = [ ./scripts/docker-entrypoint.sh ];
      ExposedPorts."5985/tcp" = { };
      Volumes."/faraday-config" = { };
      Volumes."/faraday-license" = { };
      Volumes."/faraday-storage" = { };
      Env = [ "FARADAY_HOME=/home/faraday" ];
    };
    extraCommands = ''
      # Note: The current dir is the container's root file system
      mkdir -p opt usr/bin
      cp ${./scripts/docker-server.ini} server.ini
      cp ${
        ./scripts/docker-entrypoint.sh
      } .  # Not required, but useful for debug
      cp ${coreutils}/bin/env usr/bin/env
      ln -s ${faraday-server} opt/faraday
      ln -s /home/faraday/.faraday/storage faraday-storage
      ln -s /home/faraday/.faraday/config faraday-config
    '';
  };

  systemdUnit =
    let home = if isNull systemHome then "/home/${systemUser}" else systemHome;
    in writeText "faraday-server.service" ''
      [Unit]
      Description=Faraday Server
      After=network.target

      [Service]
      Type=exec
      UMask=2002
      User=${systemUser}
      Group=${systemGroup}
      Environment=FARADAY_HOME=${home}
      ExecStart=${faraday-server}/bin/faraday-server \
        --port ${builtins.toString port} \
        --websocket_port ${builtins.toString websocketPort} \
        --bind_address ${bindAddress}
      Restart=always

      [Install]
      WantedBy=multi-user.target
    '';

  pynixify = let
    src = builtins.fetchGit {
      url = "https://github.com/cript0nauta/pynixify.git";
      ref = "refs/heads/main";
    };

    original =
      # TODO: use python 3.8 after migrating to 20.09
      python37Packages.callPackage "${src}/nix/packages/pynixify" { };

  in original.overridePythonAttrs (drv: {
    # based in https://github.com/cript0nauta/pynixify/blob/main/default.nix
    checkInputs = drv.checkInputs ++ [ nix nixfmtCustom bats ];

    checkPhase = ''
      mypy pynixify/ tests/ acceptance_tests/
      pytest tests/ -m 'not usesnix'  # We can't run Nix inside Nix builds
    '';

    postInstall = ''
      # Add nixfmt to pynixify's PATH
      wrapProgram $out/bin/pynixify --prefix PATH : "${nixfmtCustom}/bin"
    '';
  });

  nixfmtCustom =
    # custom wrapper of nixfmt that sets the column width to 1. This will force
    # splitting function arguments into separate lines and prevent merge
    # conflicts with our commercial versions.
    writeShellScriptBin "nixfmt" ''
      exec ${nixfmt}/bin/nixfmt --width=1 $@
    '';

  runPynixify =
    writeShellScriptBin "run-pynixify" ''
      export PATH=${pynixify}/bin:$PATH
      ${pynixifyCommand}
    '';
}