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

let
  cfg = config.services.iam;
in
{
  options.services.iam = {
    enable = lib.mkEnableOption "iam service";

    port = lib.mkOption {
      type = lib.types.port;
      default = 3000;
      description = "Port for iam API";
    };

    dataDir = lib.mkOption {
      type = lib.types.path;
      default = "/var/lib/iam";
      description = "Data directory for iam";
    };

    settings = lib.mkOption {
      type = lib.types.attrs;
      default = {};
      description = "Additional configuration settings";
    };

    package = lib.mkOption {
      type = lib.types.package;
      default = pkgs.iam-server or (throw "iam-server package not found");
      description = "Package to use for iam";
    };
  };

  config = lib.mkIf cfg.enable {
    # Create system user
    users.users.iam = {
      isSystemUser = true;
      group = "iam";
      description = "IAM service user";
      home = cfg.dataDir;
    };

    users.groups.iam = {};

    # Create systemd service
    systemd.services.iam = {
      description = "IAM Identity and Access Management Service";
      wantedBy = [ "multi-user.target" ];
      after = [ "network.target" "flaredb.service" ];
      requires = [ "flaredb.service" ];

      serviceConfig = {
        Type = "simple";
        User = "iam";
        Group = "iam";
        Restart = "on-failure";
        RestartSec = "10s";

        # State directory management
        StateDirectory = "iam";
        StateDirectoryMode = "0750";

        # Security hardening
        NoNewPrivileges = true;
        PrivateTmp = true;
        ProtectSystem = "strict";
        ProtectHome = true;
        ReadWritePaths = [ cfg.dataDir ];

        # Start command
        ExecStart = "${cfg.package}/bin/iam-server --addr 0.0.0.0:${toString cfg.port}";
      };
    };
  };
}