{
  pkgs,
  config,
  lib,
  ...
}:
with lib; let
  cfg = config.services.bitwarden_directory_connector;

  ldap_data = builtins.toJSON cfg.ldap;
  sync_data = builtins.toJSON cfg.sync;
in {
  imports = [];

  options.services.bitwarden_directory_connector = {
    enable = mkEnableOption "Bitwarden Directory Connector";

    package = mkOption {
      type = types.package;
      default = pkgs.bitwarden-directory-connector;
      defaultText = literalExpression "pkgs.bitwarden-directory-connector";
      description = lib.mdDoc "Reference to the Bitwarden Directory Connector package";
      example = literalExpression "pkgs.bitwarden-directory-connector-example";
    };

    binary_name = mkOption {
      type = types.str;
      description = lib.mdDoc "The main binary for the connector.";
      default = "bitwarden-directory-connector";
    };

    domain = mkOption {
      type = types.str;
      description = lib.mdDoc "The domain the Bitwarden/Vaultwarden is accessable on.";
      example = "https://vaultwarden.example.com";
    };

    user = mkOption {
      type = types.str;
      description = lib.mdDoc "User to run the program.";
      default = "bwdc";
    };

    directory = mkOption {
      type = types.str;
      description = lib.mdDoc "Folder to store the config file.";
      default = "/etc/bitwarden/bwdc";
    };

    pw_env = mkOption {
      type = types.str;
      description = lib.mdDoc "The ENV var that the ldap password is stored.";
      default = "LDAP_PW";
    };
    interval = mkOption {
      type = types.str;
      default = "*:0,15,30,45";
      description = lib.mdDoc "When to run the connector, OnCalendar syntax.";
    };

    ldap = mkOption {
      description = lib.mdDoc "Options to configurate LDAP.";
      type = types.submodule {
        freeformType = types.attrsOf (pkgs.formats.json {}).type;

        options = {
          ssl = mkOption {
            type = types.bool;
            default = false;
            description = lib.mdDoc "Use SSL.";
          };
          startTls = mkOption {
            type = types.bool;
            default = false;
            description = lib.mdDoc "Use STARTTLS.";
          };
          sslAllowUnauthorized = mkOption {
            type = types.bool;
            default = false;
            description = lib.mdDoc "";
          };
          port = mkOption {
            type = types.int;
            default = 389;
            description = lib.mdDoc "Port LDAP is accessable on";
          };
          currentUser = mkOption {
            type = types.bool;
            default = false;
            description = lib.mdDoc "Unknown what this does.";
          };
          ad = mkOption {
            type = types.bool;
            default = false;
            description = lib.mdDoc "Is Active Directory.";
          };
          pagedSearch = mkOption {
            type = types.bool;
            default = false;
            description = lib.mdDoc "The LDAP server paginates search results.";
          };

          hostname = mkOption {
            type = types.str;
            description = lib.mdDoc "The host the LDAP is accessable on.";
            example = "ldap.example.com";
          };

          rootPath = mkOption {
            type = types.str;
            description = lib.mdDoc "Root path for LDAP";
            example = "dc=example,dc=com";
          };

          username = mkOption {
            type = types.str;
            description = lib.mdDoc "The user to authenticate as.";
            example = "cn=admin,dc=example,dc=com";
          };
        };
      };
    };

    sync = mkOption {
      description = lib.mdDoc "Options to configurate what gets synced.";
      type = types.submodule {
        freeformType = types.attrsOf (pkgs.formats.json {}).type;

        options = {
          removeDisabled = mkOption {
            type = types.bool;
            default = true;
            description = lib.mdDoc "Remove users from bitwarden groups if no longer in the ldap group.";
          };
          overwriteExisting = mkOption {
            type = types.bool;
            default = false;
            description =
              lib.mdDoc "Remove and re-add users/groups, See https://bitwarden.com/help/user-group-filters/#overwriting-syncs for more details.";
          };
          largeImport = mkOption {
            type = types.bool;
            default = false;
            description = lib.mdDoc "Enable if you are syncing more than 2000 users/groups.";
          };

          memberAttribute = mkOption {
            type = types.str;
            description = lib.mdDoc "Attribute that lists members in a LDAP group.";
            example = "uniqueMember";
          };

          creationDateAttribute = mkOption {
            type = types.str;
            description = lib.mdDoc "Attribute that lists a users creation date.";
            example = "whenCreated";
          };

          useEmailPrefixSuffix = mkOption {
            type = types.bool;
            default = false;
            description = lib.mdDoc "If a user has no email address, combine a username prefix with a suffix value to form an email.";
          };
          emailPrefixAttribute = mkOption {
            type = types.str;
            description = lib.mdDoc "Attribute that has a users username.";
            default = "accountName";
          };
          emailSuffix = mkOption {
            type = types.str;
            description = lib.mdDoc "Suffix for the email, normally @example.com.";
            default = "@example.com";
          };

          users = mkOption {
            type = types.bool;
            default = false;
            description = lib.mdDoc "Sync users.";
          };
          userPath = mkOption {
            type = types.str;
            description = lib.mdDoc "User directory, relative to root.";
            default = "ou=users";
          };
          userObjectClass = mkOption {
            type = types.str;
            description = lib.mdDoc "A class that users will have.";
            default = "inetOrgPerson";
          };
          userEmailAttribute = mkOption {
            type = types.str;
            description = lib.mdDoc "Attribute for a users email.";
            default = "mail";
          };
          userFilter = mkOption {
            type = types.str;
            description = lib.mdDoc "Filter for users.";
            example = "(memberOf=cn=sales,ou=groups,dc=example,dc=com)";
            default = "";
          };

          groups = mkOption {
            type = types.bool;
            default = false;
            description = lib.mdDoc "Sync groups.";
          };
          groupPath = mkOption {
            type = types.str;
            description = lib.mdDoc "Group directory, relative to root.";
            default = "ou=groups";
          };
          groupObjectClass = mkOption {
            type = types.str;
            description = lib.mdDoc "A class that groups will have.";
            default = "groupOfNames";
          };
          groupNameAttribute = mkOption {
            type = types.str;
            description = lib.mdDoc "Attribute for a name of group.";
            default = "cn";
          };
          groupFilter = mkOption {
            type = types.str;
            description = lib.mdDoc "Filter for groups.";
            example = "(cn=sales)";
            default = "";
          };
        };
      };
    };

    env = {
      ldap = mkOption rec {
        type = types.str;
        description = "Auth for the LDAP, has value defined in {option}`pw_env";
      };
      bitwarden = mkOption rec {
        type = types.str;
        description = "Auth for Bitwarden, has BW_CLIENTID and BW_CLIENTSECRET";
      };
    };
  };

  config = mkIf cfg.enable {
    users.groups."${cfg.user}" = {};

    users.users."${cfg.user}" = {
      createHome = true;
      isSystemUser = true;
      home = "${cfg.directory}";
      group = "${cfg.user}";
      homeMode = "711";
    };

    systemd = {
      timers.bitwarden_directory_connector = {
        description = "Sync timer for Bitwarden Directory Connector";
        wantedBy = ["timers.target"];
        partOf = ["bitwarden_directory_connector.service"];
        timerConfig = {
          OnCalendar = cfg.interval;
          Unit = "bitwarden_directory_connector.service";
          Persistent = true;
        };
      };

      services.bitwarden_directory_connector = {
        description = "Main process for Bitwarden Directory Connector";
        wantedBy = ["multi-user.target"];
        after = ["network-online.target"];
        wants = [];
        path = [pkgs.jq];

        environment = {
          BITWARDENCLI_CONNECTOR_APPDATA_DIR = cfg.directory;
          BITWARDENCLI_CONNECTOR_PLAINTEXT_SECRETS = "true";
        };

        serviceConfig = {
          Type = "oneshot";
          User = "${cfg.user}";
          Group = "${cfg.user}";
          ExecStartPre = pkgs.writeShellScript "bitwarden_directory_connector-config" ''
            # create the config file
            ${cfg.package}/bin/${cfg.binary_name} data-file
            touch -- ${escapeShellArg cfg.directory}/data.json.tmp
            chmod 600 ${escapeShellArg cfg.directory}/data.json
            chmod 600 -- ${escapeShellArg cfg.directory}/data.json.tmp

            ${cfg.package}/bin/${cfg.binary_name} config server ${cfg.domain}

            # now login to set credentials
            ${cfg.package}/bin/${cfg.binary_name} login

            jq '.authenticatedAccounts[0] as $account
              | .[$account].directoryConfigurations.ldap |= $ldap_data
              | .[$account].directorySettings.organizationId |= $orgID
              | .[$account].directorySettings.sync |= $sync_data' \
              --argjson ldap_data ${escapeShellArg ldap_data} \
              --arg orgID "''${BW_CLIENTID//organization.}" \
              --argjson sync_data ${escapeShellArg sync_data} \
              ${escapeShellArg cfg.directory}/data.json \
              > ${escapeShellArg cfg.directory}/data.json.tmp

            mv -f -- ${escapeShellArg cfg.directory}/data.json.tmp ${escapeShellArg cfg.directory}/data.json

            # final config
            ${cfg.package}/bin/${cfg.binary_name} config directory 0
            ${cfg.package}/bin/${cfg.binary_name} config ldap.password --secretenv ${cfg.pw_env}
          '';

          ExecStart = "${cfg.package}/bin/${cfg.binary_name} sync";

          ExecStartPost = pkgs.writeShellScript "bitwarden_directory_connector-cleanup" ''
            rm -f -- ${escapeShellArg cfg.directory}/data.json
          '';

          EnvironmentFile = [
            "${cfg.env.ldap}"
            "${cfg.env.bitwarden}"
          ];
        };
      };
    };
  };

  meta = with lib; {
    maintainers = with maintainers; [Silver-Golden];
  };
}