{ data, lib, ... }:
let

  pns = data.services;
  marvinIP = data.hosts.marvin.ts.ip4;
  marvin = "http://${marvinIP}";
  inherit (data) tsNet;

in
rec {

  /**
    Caddy multiple host creation function

     Allows creation of a set of caddy hosts, based on a function and a list of service names

     # Example
     ```nix
     mkHosts mkDirect [ "service-a" "service-b" ]
     ```

     # Type
     ```
     mkHosts :: Function -> [String] -> AttrSet
     ```

     # Arguments

     - [function] The function to be applied to the services list
     - [services] The services to pass to the function
  */
  mkHosts = function: services: lib.listToAttrs (map function services);

  /**
    Anubis-proxied host creation function

     Allows creation of an Anubis-proxied host

     # Example
     ```nix
     mkAnubis "service-a"
     => { service-a = {
       extraConfig = ''
         reverse_proxy 100.123.15.72:1234 {
           header_up X-Real-Ip {remote_host}
           header_up X-Http-Version {http.request.proto}
         }
       '';
     }; }
     ```

     # Type
     ```
     mkAnubis :: String  -> AttrSet
     ```

     # Arguments

     - [service] The service to create a caddy host for
  */
  mkAnubis =
    service:
    lib.nameValuePair "${pns.${service}.extUrl}" {
      extraConfig = ''
        reverse_proxy ${marvin}:${toString pns.${service}.anubis} {
          header_up X-Real-Ip {remote_host}
          header_up X-Http-Version {http.request.proto}
        }
      '';
    };

  /**
    Anubis-proxied multiple host creation function

     Allows creation of several Anubis-proxied hosts

     # Example
     ```nix
     mkAnubisSites ["service-a"]
     => { service-a = {
       extraConfig = ''
         reverse_proxy 100.123.15.72:1234 {
           header_up X-Real-Ip {remote_host}
           header_up X-Http-Version {http.request.proto}
         }
       '';
     }; }
     ```

     # Type
     ```
     mkAnubisSites :: [String]  -> AttrSet
     ```

     # Arguments

     - [services] The list of services to create Caddy hosts for
  */
  mkAnubisSites = services: mkHosts mkAnubis services;

  /**
    Tailscale-only host creation function

     Allows creation of a service that will only be offered inside the tailnet.

     # Example
     ```nix
     mkTs "service-a"
     => { "service-a.example.ts.net" = {
       extraConfig = ''
         bind tailscale/service-a
         tailscale_auth
         reverse_proxy 100.123.15.72:1234
       '';
     }; }
     ```

     # Type
     ```
     mkTs :: String  -> AttrSet
     ```

     # Arguments

     - [service] The service to create a Tailscale-only host for
  */
  mkTs =
    service:
    lib.nameValuePair "${pns.${service}.tsHost}.${tsNet}" {
      extraConfig = ''
        bind tailscale/${pns.${service}.tsHost}
        tailscale_auth
        reverse_proxy ${marvin}:${toString pns.${service}.port}
      '';
    };

  /**
    Tailscale-only multiple host creation function

     Allows creation of several Tailscale-only hosts

     # Example
     ```nix
     mkTs ["service-a"]
     => { "service-a.example.ts.net" = {
       extraConfig = ''
         bind tailscale/service-a
         tailscale_auth
         reverse_proxy 100.123.15.72:1234
       '';
     }; }
     ```

     # Type
     ```
     mkTsSites :: [String]  -> AttrSet
     ```

     # Arguments

     - [services] The list of services to create Tailscale-only hosts for
  */
  mkTsSites = services: mkHosts mkTs services;

  /**
    Direct connection host creation function

     Allows creation of a service that will be proxied via Caddy, but not protected by Anubis.

     # Example
     ```nix
     mkDirect "service-a"
     => { "service-a.example.com" = {
       extraConfig = ''
         reverse_proxy 100.123.15.72:1234
       '';
     }; }
     ```

     # Type
     ```
     mkDirect :: String  -> AttrSet
     ```

     # Arguments

     - [service] The service to create a direct host for
  */
  mkDirect =
    service:
    lib.nameValuePair "${pns.${service}.extUrl}" {
      extraConfig = ''
        reverse_proxy ${marvin}:${toString pns.${service}.port}
      '';
    };

  /**
    Direct connection multiple host creation function

     Allows creation of several directly-connected hosts

     # Example
     ```nix
     mkDirectSites ["service-a"]
     => { "service-a.example.com" = {
       extraConfig = ''
         reverse_proxy 100.123.15.72:1234
       '';
     }; }
     ```

     # Type
     ```
     mkDirectSites :: [String]  -> AttrSet
     ```

     # Arguments

     - [services] The list of services to create Tailscale-only hosts for
  */
  mkDirectSites = services: mkHosts mkDirect services;
}