{ config, lib, pkgs, ... }:

with lib;

let
  cfg = config.services.infinoted;
in {
  options.services.infinoted = {
    enable = mkEnableOption "infinoted";

    package = mkOption {
      type = types.package;
      default = pkgs.libinfinity;
      defaultText = literalExpression "pkgs.libinfinity";
      description = lib.mdDoc ''
        Package providing infinoted
      '';
    };

    keyFile = mkOption {
      type = types.nullOr types.path;
      default = null;
      description = lib.mdDoc ''
        Private key to use for TLS
      '';
    };

    certificateFile = mkOption {
      type = types.nullOr types.path;
      default = null;
      description = lib.mdDoc ''
        Server certificate to use for TLS
      '';
    };

    certificateChain = mkOption {
      type = types.nullOr types.path;
      default = null;
      description = ''
        Chain of CA-certificates to which our `certificateFile` is relative.
        Optional for TLS.
      '';
    };

    securityPolicy = mkOption {
      type = types.enum ["no-tls" "allow-tls" "require-tls"];
      default = "require-tls";
      description = lib.mdDoc ''
        How strictly to enforce clients connection with TLS.
      '';
    };

    port = mkOption {
      type = types.port;
      default = 6523;
      description = lib.mdDoc ''
        Port to listen on
      '';
    };

    rootDirectory = mkOption {
      type = types.path;
      default = "/var/lib/infinoted/documents/";
      description = lib.mdDoc ''
        Root of the directory structure to serve
      '';
    };

    plugins = mkOption {
      type = types.listOf types.str;
      default = [ "note-text" "note-chat" "logging" "autosave" ];
      description = lib.mdDoc ''
        Plugins to enable
      '';
    };

    passwordFile = mkOption {
      type = types.nullOr types.path;
      default = null;
      description = lib.mdDoc ''
        File to read server-wide password from
      '';
    };

    extraConfig = mkOption {
      type = types.lines;
      default = ''
        [autosave]
        interval=10
      '';
      description = lib.mdDoc ''
        Additional configuration to append to infinoted.conf
      '';
    };

    user = mkOption {
      type = types.str;
      default = "infinoted";
      description = lib.mdDoc ''
        What to call the dedicated user under which infinoted is run
      '';
    };

    group = mkOption {
      type = types.str;
      default = "infinoted";
      description = lib.mdDoc ''
        What to call the primary group of the dedicated user under which infinoted is run
      '';
    };
  };

  config = mkIf (cfg.enable) {
    users.users = optionalAttrs (cfg.user == "infinoted")
      { infinoted = {
          description = "Infinoted user";
          group = cfg.group;
          isSystemUser = true;
        };
      };
    users.groups = optionalAttrs (cfg.group == "infinoted")
      { infinoted = { };
      };

    systemd.services.infinoted =
      { description = "Gobby Dedicated Server";

        wantedBy = [ "multi-user.target" ];
        after = [ "network.target" ];

        serviceConfig = {
          Type = "simple";
          Restart = "always";
          ExecStart = "${cfg.package.infinoted} --config-file=/var/lib/infinoted/infinoted.conf";
          User = cfg.user;
          Group = cfg.group;
          PermissionsStartOnly = true;
        };
        preStart = ''
          mkdir -p /var/lib/infinoted
          install -o ${cfg.user} -g ${cfg.group} -m 0600 /dev/null /var/lib/infinoted/infinoted.conf
          cat >>/var/lib/infinoted/infinoted.conf <<EOF
          [infinoted]
          ${optionalString (cfg.keyFile != null) "key-file=${cfg.keyFile}"}
          ${optionalString (cfg.certificateFile != null) "certificate-file=${cfg.certificateFile}"}
          ${optionalString (cfg.certificateChain != null) "certificate-chain=${cfg.certificateChain}"}
          port=${toString cfg.port}
          security-policy=${cfg.securityPolicy}
          root-directory=${cfg.rootDirectory}
          plugins=${concatStringsSep ";" cfg.plugins}
          ${optionalString (cfg.passwordFile != null) "password=$(head -n 1 ${cfg.passwordFile})"}

          ${cfg.extraConfig}
          EOF

          install -o ${cfg.user} -g ${cfg.group} -m 0750 -d ${cfg.rootDirectory}
        '';
      };
  };
}