flake.nix

{
  description = "GRASS GIS";

  nixConfig = {
    extra-substituters = [ "https://osgeo-grass.cachix.org" ];
    extra-trusted-public-keys = [ "osgeo-grass.cachix.org-1:rLnUl3u0ikSIudZ/oBfTqTL7mb3qwYmfmtuwexPpHjw=" ];

    bash-prompt = "\\[\\033[1m\\][grass-dev]\\[\\033\[m\\]\\040\\w >\\040";
  };

  inputs = {
    nixpkgs.url = "github:NixOS/nixpkgs/nixpkgs-unstable";
  };

  outputs = inputs@{ flake-parts, ... }:
    flake-parts.lib.mkFlake { inherit inputs; } {

      systems = [ "x86_64-linux" ];

      perSystem = { config, self', inputs', pkgs, system, ... }: {

        packages.grass = pkgs.callPackage ./package.nix { };

        devShells.default =
          let
            pyPackages = pkgs.python311Packages;

          in
          pkgs.mkShell {
            inputsFrom = [ self'.packages.grass ];

            # additional packages
            buildInputs =  with pyPackages; [
                pytest
              ];

            shellHook = ''
              function dev-help {
                echo -e "\nWelcome to a GRASS development environment !"
                echo "Build GRASS using following commands:"
                echo
                echo " 1.  ./configure --prefix=\$(pwd)/app"
                echo " 2.  make -j$(nproc)"
                echo " 3.  make install"
                echo
                echo "Run tests:"
                echo
                echo " 1.  export PYTHONPATH=\$(app/bin/grass --config python_path):\$PYTHONPATH"
                echo " 2.  export LD_LIBRARY_PATH=\$(app/bin/grass --config path)/lib:\$LD_LIBRARY_PATH"
                echo " 3.  pytest"
                echo
                echo "Note: run 'nix flake update' from time to time to update dependencies."
                echo
                echo "Run 'dev-help' to see this message again."
              }

              dev-help
            '';
          };
      };

      flake = { };
    };
}