mpd-discord-presence/flake.nix

{
  description = "MPD Discord daemon";

  inputs = {
    nixpkgs.url = "github:NixOS/nixpkgs/nixos-unstable";
    flake-utils.url = "github:numtide/flake-utils";
    fenix = {
      url = "github:nix-community/fenix";
      inputs.nixpkgs.follows = "nixpkgs";
    };
  };

  outputs = { self, nixpkgs, flake-utils, fenix, ... }:
    let
      overlay = final: prev:
        let
          fenixPkgs = fenix.packages.${final.stdenv.hostPlatform.system};
          rustToolchain =
            with fenixPkgs;
            combine (with stable; [
              clippy
              rustc
              cargo
              rustfmt
              rust-src
            ]);
        in
        {
          inherit rustToolchain;

          mpd-discord-presence = final.rustPlatform.buildRustPackage {
            pname = "mpd-discord-presence";
            version = "0.1.0";

            src = self;

            cargoLock.lockFile = ./Cargo.lock;

            enableParallelBuild = true;

            meta = {
              description = "MPD Discord daemon";
              homepage = "https://git.slendi.dev/Slendi/mpd-discord-presence";
              license = final.lib.licenses.gpl3;
              mainProgram = "mpd-discord-presence";
            };
          };
        };
    in
    {
      overlays.default = overlay;

      homeManagerModules.mpd-discord-presence = { config, lib, pkgs, ... }:
        let
          cfg = config.services.mpd-discord-presence;
        in
        {
          options.services.mpd-discord-presence = {
            enable = lib.mkEnableOption "mpd-discord-presence (systemd user service)";

            package = lib.mkOption {
              type = lib.types.package;
              default = self.packages.${pkgs.system}.mpd-discord-presence;
              description = "Package providing the mpd-discord-presence binary.";
            };

            extraArgs = lib.mkOption {
              type = lib.types.listOf lib.types.str;
              default = [];
              description = "Extra CLI args passed to mpd-discord-presence.";
            };
          };

          config = lib.mkIf cfg.enable {
            home.packages = [ cfg.package ];

            systemd.user.services.mpd-discord-presence = {
              Unit = {
                Description = "MPD Discord Presence";
                Wants = [ "mpd.service" ];
                After = [ "mpd.service" "network-online.target" ];
              };

              Service = {
                ExecStart = "${cfg.package}/bin/mpd-discord-presence ${lib.escapeShellArgs cfg.extraArgs}";
                Restart = "on-failure";
                RestartSec = 2;
              };

              Install = {
                WantedBy = [ "default.target" ];
              };
            };
          };
        };
    }
    // flake-utils.lib.eachDefaultSystem (system:
      let
        pkgs = import nixpkgs {
          inherit system;
          overlays = [ overlay ];
        };
      in
      {
        packages = {
          mpd-discord-presence = pkgs.mpd-discord-presence;
          default = pkgs.mpd-discord-presence;
        };

        devShells.default = pkgs.mkShell {
          packages = with pkgs; [
            rustToolchain
            openssl
            pkg-config
            cargo-deny
            cargo-edit
            cargo-watch
            rust-analyzer
          ];

          shellHook = ''
            export RUST_SRC_PATH="${pkgs.rustToolchain}/lib/rustlib/src/rust/library"
          '';
        };
      });
}