# NOTE: to convert to a poetry2nix env like this here are the
# steps:
# - install poetry in your system nix config
# - convert the repo to use poetry using `poetry init`:
#   https://python-poetry.org/docs/basic-usage/#initialising-a-pre-existing-project
# - then manually ensuring all deps are converted over:
# - add this file to the repo and commit it
# - 
{
  description = "piker: trading gear for hackers (pkged with poetry2nix)";

  inputs.flake-utils.url = "github:numtide/flake-utils";
  inputs.nixpkgs.url = "github:NixOS/nixpkgs/nixos-unstable";

  # see https://github.com/nix-community/poetry2nix/tree/master#api
  inputs.poetry2nix = {
    url = "github:nix-community/poetry2nix";
    # url = "github:K900/poetry2nix/qt5-explicit-deps";
    # url = "/home/lord_fomo/repos/poetry2nix";

    inputs.nixpkgs.follows = "nixpkgs";
  };

  outputs = {
    self,
    nixpkgs,
    flake-utils,
    poetry2nix,
  }:
    # TODO: build cross-OS and use the `${system}` var thingy..
    flake-utils.lib.eachDefaultSystem (system:
      let
        # use PWD as sources
        projectDir = ./.;
        pyproject = ./pyproject.toml;
        poetrylock = ./poetry.lock;

        # TODO: port to 3.11 and support both versions?
        python = "python3.10";

        # for more functions and examples.
        # inherit
        # (poetry2nix.legacyPackages.${system})
        # mkPoetryApplication;
        # pkgs = nixpkgs.legacyPackages.${system};

        pkgs = nixpkgs.legacyPackages.x86_64-linux;
        lib = pkgs.lib;
        p2npkgs = poetry2nix.legacyPackages.x86_64-linux;

        # define all pkg overrides per dep, see edgecases.md:
        # https://github.com/nix-community/poetry2nix/blob/master/docs/edgecases.md
        # TODO: add these into the json file:
        # https://github.com/nix-community/poetry2nix/blob/master/overrides/build-systems.json
        pypkgs-build-requirements = {
          asyncvnc = [ "setuptools" ];
          eventkit = [ "setuptools" ];
          ib-insync = [ "setuptools" "flake8" ];
          msgspec = [ "setuptools"];
          tabcompleter = [ "setuptools" ];
          pdbp = [ "setuptools" ];
          xonsh = [ "setuptools" ];
          trio-typing = [ "setuptools" ];
          trio-util = [ "setuptools" ];
          tricycle = [ "setuptools" ];
          tractor = [ "setuptools" ];
          pyqt6-sip = [ "setuptools" ];

          # don't need these right?
          # tomlkit = [ "setuptools" ];
        };

        # auto-generate override entries
        p2n-overrides = p2npkgs.defaultPoetryOverrides.extend (self: super:
          builtins.mapAttrs (package: build-requirements:
            (builtins.getAttr package super).overridePythonAttrs (old: {
              buildInputs = (
                old.buildInputs or [ ]
              ) ++ (
                builtins.map (
                  pkg: if builtins.isString pkg then builtins.getAttr pkg super else pkg
                  ) build-requirements
              );
            })
          ) pypkgs-build-requirements
        );

      in
        {
          # let
          # devEnv = poetry2nix.mkPoetryEnv {
          #     projectDir = ./.;
          # };

          packages = {
            # piker = poetry2nix.legacyPackages.x86_64-linux.mkPoetryEditablePackage {
            #   editablePackageSources = { piker = ./piker; };
            piker = p2npkgs.mkPoetryApplication {
              projectDir = projectDir;

              # SEE ABOVE for auto-genned input set, override
              # buncha deps with extras.. like `setuptools` mostly.
              # TODO: maybe propose a patch to p2n to show that you
              # can even do this in the edgecases docs?
              overrides = p2n-overrides.extend(
                final: prev: {

                  # TODO: get this workin with p2n and nixpkgs..
                  # pyqt6 = prev.pyqt6.override {
                  #   preferWheel = true;
                  # };

                  # NOTE: this DOESN'T work atm but after a fix
                  # to poetry2nix, it will and actually this line
                  # won't be needed - thanks @k900:
                  # https://github.com/nix-community/poetry2nix/pull/1257
                  pyqt5 = prev.pyqt5.override {
                    withWebkit = false;
                    preferWheel = true;
                  };

                  # see PR from @k900:
                  # https://github.com/nix-community/poetry2nix/pull/1257
                  pyqt5-qt5 = prev.pyqt5-qt5.override {
                    withWebkit = false;
                    preferWheel = true;
                  };

                  # TODO: patch in an override for polars to build
                  # from src! See the details likely needed from
                  # the cryptography entry:
                  # https://github.com/nix-community/poetry2nix/blob/master/overrides/default.nix#L426-L435
                  polars = prev.polars.override {
                    preferWheel = true;
                  };
                }
              );
            };
        };

        # output-attr that `nix-develop` scans for:
        # https://nixos.org/manual/nix/stable/command-ref/new-cli/nix3-develop.html#flake-output-attributes
        devShells.default = pkgs.mkShell {
          # packages = [ poetry2nix.packages.${system}.poetry ];
          packages = [ poetry2nix.packages.x86_64-linux.poetry ];
          inputsFrom = [ self.packages.x86_64-linux.piker ];

          # TODO: boot xonsh inside the poetry virtualenv when
          # defined via a custom entry point?
          # NOTE XXX: apparently DON'T do these..?
          # shellHook = "poetry run xonsh";
          # shellHook = "poetry shell";
        };
      }
    );
}