{ config, pkgs, lib, ... }:
let 
  cfg = config.services.matrix-synapse;
  federationSenders = lib.range 0 (cfg.federationSenders - 1);
in
{
  services.matrix-synapse = lib.mkIf (cfg.federationSenders > 0) {
    settings = {
      # Instance map is not needed for federation senders
      send_federation = false;
      federation_sender_instances = lib.map (index: "federation_sender-${toString index}") federationSenders;
      outbound_federation_restricted_to = lib.map (index: "federation_sender-${toString index}") federationSenders;
    };

    workers = lib.listToAttrs (lib.map (index: {
      name = "federation_sender-${toString index}";
      value = {
        worker_app = "synapse.app.generic_worker";
        worker_listeners = [
          {
            type = "http";
            path = "/run/matrix-synapse/pusher-${toString index}.sock";
            resources = [
              {
                names = ["replication"];
                compress = false;
              }
            ];
          }
        ];
      };
    }) federationSenders);
  };
}