# `checks.module-eval-swarm-services-switch` — see ./lib.nix for the shared
# rationale (why this suite exists, naming convention, "evaluates
# not executes").
{
  pkgs,
  lib,
  self,
  nixosSystem,
}:
let
  inherit
    (import ./lib.nix {
      inherit
        pkgs
        lib
        self
        nixosSystem
        ;
    })
    hive
    hiveWithController
    runGroup
    bridgePortsOrNone
    swarmServiceEnables
    ;

  # A dedicated services host with hives elsewhere: the swarm-services
  # toggle and no hive, the recipe docs/swarm/services.md gives.
  swarmServicesOnly = hive {
    deploy.hive-controller.enable = false;
    deploy.allSwarmServices = true;
  };

  # A services host with hives elsewhere and the store elsewhere too: no hive
  # and no store identity minted here.
  swarmServicesOnlyNoStore = hive {
    deploy.hive-controller.enable = false;
    deploy.allSwarmServices = true;
    deploy.bao.enable = false;
  };

  # A dedicated secret-store host: no hive, and the store's browser UI the
  # only swarm name its gateway fronts.
  storeOnlyNoHive = hive {
    deploy.hive-controller.enable = false;
    deploy.bao.enable = true;
  };

  # The homeserver on a host without a hive.
  matrixNoHive = hive {
    deploy.hive-controller.enable = false;
    deploy.matrix.enable = true;
  };

  # The same switch with every service it owns placed elsewhere, so the only
  # thing that can enable the gateway/resolver/bridge here is that toggle's
  # own module — each service module asserts them from its own `enable`.
  swarmServicesSwitchAlone = hive {
    deploy.hive-controller.enable = false;
    deploy.allSwarmServices = true;
    deploy.matrix.enable = false;
    otel.enable = false;
    deploy.authelia.enable = false;
    deploy.nats.enable = false;
    deploy.swarm-otel.enable = false;
    deploy.victoriametrics.enable = false;
    deploy.grafana.enable = false;
    deploy.victorialogs.enable = false;
    deploy.bao.enable = false;
    deploy.forgejo.enable = false;
  };

  # Ports asked for on such a host. The request is the whole condition: the
  # firewall hole exists because an operator named a port, not because the
  # hive is running, and an agent reaching a host service is a claim about
  # the host's own listeners either way.
  exposedPortsNoHive = hive {
    deploy.hive-controller.enable = false;
    network.exposeHostPorts = [ 5432 ];
  };

  # The swarm UI where its own toggle is on — the control the absence arm
  # needs, since nothing else in this suite renders this vhost and an arm
  # saying "it is not there" would hold just as well if it were never there.
  # Package stubbed per this file's header: the vhost roots at it.
  swarmUiHere = hive {
    deploy.swarm-ui.enable = true;
    deploy.swarm-ui.package = pkgs.emptyDirectory;
  };

  # The swarm's shared services hosted HERE without the all-local mode — a
  # services box with hives elsewhere, the shape ./host-modules/
  # swarm-required-services.nix documents the switch for.
  swarmServicesHere = hiveWithController { deploy.allSwarmServices = true; };

  # Same, with one of those services placed on another host. Every derivation
  # in that module is `mkDefault` so this stays expressible.
  swarmServicesBaoElsewhere = hive {
    deploy.allSwarmServices = true;
    deploy.bao.enable = false;
  };

  # The swarm-wide forge objects are the controller's (forge/objects.rs), so
  # the mirror list and the org avatar go to its unit, not hive-c0re's.
  aMirror = {
    upstream = "https://example.invalid/tool";
    dest = "mirrors/tool";
  };
  controllerWithMirrors = hiveWithController {
    deploy.swarm-controller.enable = true;
    deploy.forgejo.enable = true;
    deploy.forgejo.mirrors = [ aMirror ];
    c0re.orgAvatarPng = "/etc/marker-avatar.png";
  };
  mirrorsNoController = hive {
    deploy.forgejo.enable = true;
    deploy.forgejo.mirrors = [ aMirror ];
  };
  controllerWithSelfActions = hive {
    deploy.swarm-controller.enable = true;
    deploy.forgejo.enable = true;
    deploy.forgejo.mirrors = [ aMirror ];
    deploy.forgejo.actionsFromSelf = true;
  };

  # The controller with every shared service on another host, and the same
  # controller hosting them all: the swarm UI's links must not tell the two
  # apart.
  controllerAlone = hive { deploy.swarm-controller.enable = true; };
  controllerWithServices = hive {
    deploy.swarm-controller.enable = true;
    deploy.allSwarmServices = true;
  };

  # Each shared service with a web UI, and the link it must have: the label
  # and the swarm-level domain the URL is built from.
  swarmServiceLinkDomains =
    let
      s = controllerAlone.services.hyperhive.swarm;
    in
    {
      Authelia = s.authelia.domain;
      Grafana = s.grafana.domain;
      Metrics = s.victoriametrics.domain;
      Logs = s.victorialogs.domain;
      Matrix = s.matrix.gatewayHost;
      Bao = s.bao.ui.domain;
      Forge = s.forge.domain;
    };
  swarmServiceLinksOf =
    cfg:
    lib.filter (l: swarmServiceLinkDomains ? ${l.label}) cfg.services.hyperhive.swarm.controller.links;

  # Every service container at once: the services-only host plus the CI
  # runner, the one container on a netns of its own.
  serviceContainersWithCi = hive {
    deploy.hive-controller.enable = false;
    deploy.allSwarmServices = true;
    deploy.ci-runner.enable = true;
  };
  serviceContainers = serviceContainersWithCi.containers;
  cases = [
    {
      # `lib.all` over an empty set holds vacuously, so the roster is counted
      # before it is read: a helper that lost a member would otherwise turn
      # this case green by measuring nothing.
      name = "hosting the swarm's shared services turns on every service that switch owns";
      ok =
        let
          es = swarmServiceEnables swarmServicesHere;
        in
        lib.length (lib.attrNames es) == 9 && lib.all lib.id (lib.attrValues es);
    }
    {
      # The switch fills in for an operator who has not spoken and yields to
      # one who has — that is what keeps a shared service placeable on a host
      # of its own. A plain assignment or `mkForce` would satisfy both cases
      # above and break this one. `nats` is the control: without it the case
      # also passes on a fixture where nothing came on at all.
      name = "placing one shared service elsewhere survives the switch that would enable it";
      ok =
        let
          es = swarmServiceEnables swarmServicesBaoElsewhere;
        in
        !es.bao && es.nats;
    }
    {
      # The controller sits on the OTHER tier: `singleHostSwarm` places it
      # (./host-modules/local-defaults.nix) and swarm-ui follows the
      # controller. Pinned so that moving a service between tiers is a
      # decision someone makes rather than a merge nobody reads.
      name = "hosting the swarm's shared services does not make a hive the swarm's control plane";
      ok =
        !swarmServicesHere.services.hyperhive.deploy.swarm-controller.enable
        && !swarmServicesHere.services.hyperhive.deploy.swarm-ui.enable;
    }
    {
      # Control for the arm above, and the one place this slice is not inert:
      # the ports are opened because they were named, on a host that never
      # turned the hive on. The bridge firewall is the host's own, so there is
      # nothing here for the hive toggle to have been protecting.
      name = "a named exposeHostPorts opens its bridge port on the host's own say-so";
      ok = builtins.elem 5432 (bridgePortsOrNone exposedPortsNoHive);
    }
    {
      name = "the swarm UI claims the swarm apex where this host serves it";
      ok = swarmUiHere.services.nginx.virtualHosts ? "t.local";
    }
    {
      # The swarm-services toggle enables them explicitly, from its own
      # module rather than from any of their defaults.
      name = "the swarm-services toggle turns on the gateway, resolver and bridge by itself";
      ok =
        swarmServicesSwitchAlone.services.hyperhive.gateway.enable
        && swarmServicesSwitchAlone.services.hyperhive.gateway.dns.enable
        && swarmServicesSwitchAlone.services.hyperhive.network.enable;
    }
    {
      # No hive, so no hive leaf, no hive identity and no hive-domain vhost:
      # the default certificate is the swarm-services leaf, or a throwaway
      # pair until it lands. A host fronting many swarm names waits for that
      # leaf; a store-only host does not. The control is a hive host with
      # the same services.
      name = "a gateway host without a hive serves the swarm-services leaf as its default cert and has no hive-leaf unit";
      ok =
        let
          # Every hive-leaf reference a unit could carry: the leaf files,
          # the identity's file and subject. The store's own per-hive role
          # unit is left out: it writes roles for the hives in the swarm
          # directory, which live elsewhere.
          hiveLeafRefs = [
            "gateway.pem"
            "gateway-key.pem"
            "hive-leaf"
            "swarm-bao-hive-leaf-"
          ];
          noHiveLeafAnywhere =
            m:
            let
              units = removeAttrs m.systemd.services [ "swarm-bao-hive-leaf-policy" ];
              texts = lib.concatMap (u: [
                (u.script or "")
                (builtins.toJSON (u.environment or { }))
              ]) (lib.attrValues units);
            in
            !(lib.any (t: lib.any (r: lib.hasInfix r t) hiveLeafRefs) texts)
            && m.services.hyperhive.deploy.hive-controller.tls.baoHiveIdentityCertFile == null
            && noHiveSurface m;
          # No hive-domain vhost, and no vhost on the host carrying the
          # hive's locations: c0re's `/health/`, the agent routes, swagger,
          # or the hive domain's matrix discovery and `/matrix/` redirect.
          noHiveSurface =
            m:
            let
              vh = m.services.nginx.virtualHosts;
            in
            !(vh ? "h1.t.local")
            && !(lib.any (
              v:
              lib.any (l: (v.locations or { }) ? ${l}) [
                "/health/"
                "/agent/"
                "/api/docs/"
                "/matrix/"
                "= /.well-known/matrix/client"
                "= /.well-known/matrix/server"
              ]
              || lib.hasInfix "agents.conf" (v.extraConfig or "")
            ) (lib.attrValues vh));
          noHive =
            m:
            let
              s = m.systemd.services;
            in
            !(s ? hive-tls-resign) && !(m.systemd.timers ? hive-tls-resign) && noHiveLeafAnywhere m;
          waitsForLeaf =
            m:
            let
              s = m.systemd.services;
            in
            lib.elem "hive-gateway-self-signed-cert.service" s.swarm-services-cert.requiredBy
            && lib.elem "hive-gateway-self-signed-cert.service" s.swarm-services-cert.before;
          # The cert it installs on the default and swarm-services paths:
          # the services leaf when present, a throwaway pair otherwise.
          importsServicesLeafOrFallback =
            m:
            let
              imp = m.systemd.services.hive-gateway-self-signed-cert;
            in
            lib.hasInfix "cert=/var/lib/hive-tls/swarm-services.pem" imp.script
            && lib.hasInfix "openssl req -x509" imp.script
            && lib.hasInfix "cert=/var/lib/hive-gateway/tls/fallback.pem" imp.script
            && lib.hasInfix ''install -m 0644 "$cert" /var/lib/hive-gateway/tls/cert.pem'' imp.script
            && lib.hasInfix ''install -m 0644 "$cert" /var/lib/hive-gateway/tls/swarm-services.pem'' imp.script
            && lib.any (p: lib.hasPrefix "openssl" (p.pname or (p.name or ""))) imp.path;
          store = storeOnlyNoHive;
          hs = swarmServicesHere.systemd.services;
        in
        noHive swarmServicesOnly
        && noHive swarmServicesOnlyNoStore
        && noHive store
        && importsServicesLeafOrFallback swarmServicesOnly
        && importsServicesLeafOrFallback swarmServicesOnlyNoStore
        && importsServicesLeafOrFallback store
        # Fronting many swarm names: the gateway waits for their leaf.
        && waitsForLeaf swarmServicesOnly
        && waitsForLeaf swarmServicesOnlyNoStore
        # The store's UI alone: its nginx carries the passthrough to the
        # store, so it starts on the fallback with the store sealed.
        &&
          store.services.hyperhive.swarm.localServiceDomains
          == [ store.services.hyperhive.swarm.bao.ui.domain ]
        && !(waitsForLeaf store)
        # The homeserver without a hive: no hive-domain vhost at all, and the
        # homeserver's own vhost still proxies `/_matrix/`.
        && noHive matrixNoHive
        && (
          let
            gh = matrixNoHive.services.hyperhive.swarm.matrix.gatewayHost;
            vh = matrixNoHive.services.nginx.virtualHosts;
          in
          gh != null && vh ? ${gh} && lib.any (lib.hasPrefix "/_matrix") (lib.attrNames vh.${gh}.locations)
        )
        && !(store.services.nginx.virtualHosts ? "h1.t.local")
        && lib.hasInfix "want_svc=1" store.systemd.services.swarm-services-cert.script
        # Control: a hive host with the same services keeps the hive leaf,
        # its unit and identity, and the hive-domain vhost.
        && hs ? hive-tls-resign
        && lib.hasInfix "install -m 0644 /var/lib/hive-tls/gateway.pem /var/lib/hive-gateway/tls/cert.pem" hs.hive-gateway-self-signed-cert.script
        && swarmServicesHere.services.hyperhive.deploy.hive-controller.tls.baoHiveIdentityCertFile != null
        && (
          let
            l = swarmServicesHere.services.nginx.virtualHosts."h1.t.local".locations;
          in
          l ? "/api/" && l ? "/health/" && l ? "= /.well-known/matrix/client"
        )
        && !(noHiveLeafAnywhere swarmServicesHere);
    }
    {
      # Each service is gated on its own deployment toggle alone, so a host
      # that runs no hive still runs every shared service the switch turns
      # on, plus the plumbing and the self-signed CA they are served through.
      # Nothing starts the hive's own daemons. `hive-c0re` is checked by what
      # starts it rather than by key: ../host-modules/hive-network.nix's bridge
      # block writes to its environment wherever the bridge is up.
      name = "a services-only host runs the swarm's shared services and no hive";
      ok =
        let
          c = swarmServicesOnly.containers;
          s = swarmServicesOnly.systemd.services;
          h = swarmServicesOnly.services.hyperhive;
        in
        lib.all (m: c ? ${m}) [
          "swarm-authelia"
          "swarm-bao"
          "swarm-grafana"
          "swarm-victorialogs"
          "swarm-victoriametrics"
          "swarm-otel"
          "swarm-nats"
          "hive-matrix"
          "hive-forge"
        ]
        && h.gateway.enable
        && h.gateway.dns.enable
        && h.network.enable
        && s ? hive-tls-ca
        && s ? swarm-bao-pki
        && (s.hive-c0re.wantedBy or [ ]) == [ ]
        && !(swarmServicesOnly.systemd.sockets ? hive-c0re)
        && !(swarmServicesOnly.systemd.sockets ? hive-priv)
        && !(s ? swarm-bao-queue-agent);
    }
    {
      # On a controller that runs none of them, so the link cannot come from
      # the service's own module.
      name = "the swarm UI links every shared service with a web UI at its swarm domain";
      ok =
        lib.listToAttrs (map (l: lib.nameValuePair l.label l.url) (swarmServiceLinksOf controllerAlone))
        == lib.mapAttrs (_: domain: "https://${domain}/") swarmServiceLinkDomains;
    }
    {
      # Exact list equality also catches an entry rendered twice where the
      # service runs on the controller's own host.
      name = "the swarm UI's service links are the same whichever host runs the services";
      ok =
        lib.length (swarmServiceLinksOf controllerAlone)
        == lib.length (lib.attrNames swarmServiceLinkDomains)
        && swarmServiceLinksOf controllerWithServices == swarmServiceLinksOf controllerAlone;
    }
    {
      # The in-container option drives the container's firewall, and host
      # `false` with container `true` would let the container's
      # firewall.service rewrite the HOST ruleset. Counted first so a fixture
      # that lost a container can't pass by comparing fewer of them.
      name = "every service container restates its host-side privateNetwork";
      ok =
        lib.length (lib.attrNames serviceContainers) == 10
        && lib.all (
          c: c.privateNetwork == (c.config.services.hyperhive.swarmContainer.privateNetwork or null)
        ) (lib.attrValues serviceContainers);
    }
    {
      # Both values come from ../container-modules/swarm-container.nix.
      name = "a service container on the host netns runs no firewall or resolvconf of its own";
      ok =
        let
          shared = lib.filter (c: !c.privateNetwork) (lib.attrValues serviceContainers);
        in
        lib.length shared == 9
        && lib.all (
          c: !c.config.networking.firewall.enable && !c.config.networking.resolvconf.enable
        ) shared;
    }
    {
      # The `privateNetwork = true` and `writesOwnResolvConf = false` arms:
      # NixOS enables both by default, so the module must leave them alone.
      name = "a service container on a netns of its own keeps its firewall and resolvconf";
      ok =
        let
          c = serviceContainers.swarm-ci-runner.config;
        in
        c.networking.firewall.enable && c.networking.resolvconf.enable;
    }
    {
      name = "a service container that sets no stateVersion of its own is on 26.05";
      ok = serviceContainers.swarm-victoriametrics.config.system.stateVersion == "26.05";
    }
    {
      name = "a service container that pins its own stateVersion keeps it";
      ok = serviceContainers.hive-forge.config.system.stateVersion == "25.11";
    }
    {
      # An operator's explicit `false` beats every `mkDefault` assertion,
      # which is what keeps "asserted by whoever needs it" from being a
      # setting the operator cannot turn off.
      name = "an explicit gateway.enable = false wins over the modules asserting it";
      ok = !(hiveWithController { gateway.enable = false; }).services.nginx.enable;
    }
    {
      name = "declared forge mirrors reach the swarm-controller, not hive-c0re";
      ok =
        builtins.fromJSON controllerWithMirrors.systemd.services.swarm-controller.environment.SWARM_CONTROLLER_FORGE_MIRRORS
        == [ aMirror ]
        && !(controllerWithMirrors.systemd.services.hive-c0re.environment ? HYPERHIVE_FORGE_MIRRORS);
    }
    {
      name = "forge mirrors on a host without the controller warn that nothing seeds them";
      ok =
        let
          warns = cfg: lib.any (lib.hasInfix "declare them on the swarm-controller's host") cfg.warnings;
        in
        warns mirrorsNoController && !(warns controllerWithMirrors);
    }
    {
      # The mirror is what `self` resolves `actions/checkout` to, so the two
      # come together. The control is the same forge without the option.
      name = "actionsFromSelf adds the checkout mirror and resolves actions from the forge";
      ok =
        let
          mirrorsOf =
            m: builtins.fromJSON m.systemd.services.swarm-controller.environment.SWARM_CONTROLLER_FORGE_MIRRORS;
          actionsUrlOf =
            m: m.containers.hive-forge.config.services.forgejo.settings.actions.DEFAULT_ACTIONS_URL or null;
        in
        lib.elem "actions/checkout" (map (m: m.dest) (mirrorsOf controllerWithSelfActions))
        && actionsUrlOf controllerWithSelfActions == "self"
        && mirrorsOf controllerWithMirrors == [ aMirror ]
        && actionsUrlOf controllerWithMirrors == null;
    }
    {
      name = "the old c0re org-avatar option lands on the controller's unit";
      ok =
        controllerWithMirrors.systemd.services.swarm-controller.environment.SWARM_CONTROLLER_CONFIG_ORG_AVATAR_PNG
        == "/etc/marker-avatar.png"
        && !(controllerWithMirrors.systemd.services.hive-c0re.environment ? HIVE_ORG_AVATAR_PNG);
    }
  ];
in
runGroup "swarm-services-switch" cases