flake.nix

{
  description = "Poetry2nix flake";

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

    treefmt-nix.url = "github:numtide/treefmt-nix";
    treefmt-nix.inputs.nixpkgs.follows = "nixpkgs";

    nix-github-actions = {
      url = "github:nix-community/nix-github-actions";
      inputs.nixpkgs.follows = "nixpkgs";
    };
  };

  outputs =
    { self
    , nixpkgs
    , flake-utils
    , nix-github-actions
    , treefmt-nix
    , systems
    ,
    }:
    let
      eachSystem = f: nixpkgs.lib.genAttrs (import systems) (system: f nixpkgs.legacyPackages.${system});
      treefmtEval = eachSystem (pkgs: treefmt-nix.lib.evalModule pkgs ./dev/treefmt.nix);
    in
    {
      overlays.default = nixpkgs.lib.composeManyExtensions [ (import ./overlay.nix) ];
      lib.mkPoetry2Nix = { pkgs }: import ./default.nix { inherit pkgs; };

      githubActions =
        let
          mkPkgs = system:
            import nixpkgs {
              config = {
                allowAliases = false;
                allowInsecurePredicate = _: true;
              };
              overlays = [ self.overlays.default ];
              inherit system;
            };
        in
        nix-github-actions.lib.mkGithubMatrix {
          platforms = {
            "x86_64-linux" = "ubuntu-22.04";
            "x86_64-darwin" = "macos-13";
            "aarch64-darwin" = "macos-14";
          };
          checks = {
            x86_64-linux =
              let
                pkgs = mkPkgs "x86_64-linux";
              in
              import ./tests { inherit pkgs; }
              // {
                formatting = treefmtEval.x86_64-linux.config.build.check self;
              };

            x86_64-darwin =
              let
                pkgs = mkPkgs "x86_64-darwin";
                inherit (pkgs) lib;
                tests = import ./tests { inherit pkgs; };
              in
              {
                # Aggregate all tests into one derivation so that only one GHA runner is scheduled for all darwin jobs
                aggregate = pkgs.runCommand "darwin-aggregate"
                  {
                    env.TEST_INPUTS = lib.concatStringsSep " " (lib.attrValues (lib.filterAttrs (_: v: lib.isDerivation v) tests));
                  } "touch $out";
              };
            aarch64-darwin =
              let
                pkgs = mkPkgs "aarch64-darwin";
                inherit (pkgs) lib;
                tests = import ./tests { inherit pkgs; };
              in
              {
                # Aggregate all tests into one derivation so that only one GHA runner is scheduled for all darwin jobs
                aggregate =
                  pkgs.runCommand "darwin-aggregate"
                    {
                      env.TEST_INPUTS = lib.concatStringsSep " " (lib.attrValues (lib.filterAttrs (_: v: lib.isDerivation v) tests));
                    } "touch $out";
              };
          };
        };

      templates = {
        app = {
          path = ./templates/app;
          description = "An example of a NixOS container";
        };
        default = self.templates.app;
      };
    }
    // (flake-utils.lib.eachDefaultSystem (system:
    let
      pkgs = import nixpkgs {
        inherit system;
        config.allowAliases = false;
      };

      poetry2nix = import ./default.nix { inherit pkgs; };
      p2nix-tools = pkgs.callPackage ./tools { inherit poetry2nix; };
    in
    rec {
      formatter = treefmtEval.${system}.config.build.wrapper;

      packages = {
        poetry2nix = poetry2nix.cli;
        default = poetry2nix.cli;
      };

      devShells = {
        default = pkgs.mkShell {
          nativeBuildInputs = with pkgs; [
            p2nix-tools.env
            p2nix-tools.flamegraph
            nixpkgs-fmt
            poetry
            niv
            jq
            nix-prefetch-git
            nix-eval-jobs
            nix-build-uncached
          ];
        };
      };

      apps = {
        poetry = {
          # https://wiki.nixos.org/wiki/Flakes
          type = "app";
          program = "${pkgs.poetry}/bin/poetry";
        };
        poetry2nix = flake-utils.lib.mkApp { drv = packages.poetry2nix; };
        default = apps.poetry2nix;
      };
    }));
}