# orchestrator-host.nix — the host contract that nix/modules/cc-ci.nix (the orchestrator's
# loops/timers) silently assumes, made explicit and reusable: the `loops` user the agents run as,
# the standalone opencode CLI, the shared opencode web server and its basic-auth web UI,
# nix-ld so foreign binaries run on NixOS, and the tool set agents reach for.
#
# Exported from flake.nix as `nixosModules.orchestrator-host`. A host imports this together with
# `nixosModules.cc-ci-orchestrator`; the combined CI-server + orchestrator host (`#cc-ci`) also
# imports recipe-maintainers/cc-ci's `nixosModules.cc-ci-server`.
#
# History: until 2026-09 this lived (twice, drifting) in nix/hosts/cc-ci-orchestrator-hetzner/
# configuration.nix here and in notplants-nix's hosts/notplants-orchestrator/configuration.nix,
# the shared agent box that also ran lichen + project-orchestrator. The cc-ci half moved to its
# own host; this file is that half.
{ config, lib, pkgs, ... }:
let
  cfg = config.cc-ci-orchestrator;
in
{
  options.cc-ci-orchestrator = {
    ciSshHost = lib.mkOption {
      type = lib.types.str;
      default = "127.0.0.1";
      example = "100.95.31.88";
      description = ''
        Where `ssh cc-ci` (used by every skill and script that drives the CI server) connects to,
        as root with ~loops/.ssh/cc-ci-root-ed25519. On the combined host the CI server IS this
        machine, so the default is loopback; a standalone orchestrator points it at the CI
        server's tailnet address.
      '';
    };

    opencodeUiBackendPort = lib.mkOption {
      type = lib.types.port;
      default = 8090;   # not 8080: acme-dns's local API has it on the combined host
      description = ''
        Plain-HTTP port nginx listens on for the opencode UI, reachable ONLY from the docker
        bridge (firewall rule on docker_gwbridge). Traefik — which owns the public 443 on the
        combined host — terminates TLS for opencodeUiHost and forwards here; nginx adds the basic
        auth and logs failures for fail2ban with the real client IP.
      '';
    };

    opencodeUiTraefikNetwork = lib.mkOption {
      type = lib.types.nullOr lib.types.str;
      default = null;
      example = "proxy";
      description = ''
        Name of the swarm overlay network the cc-ci traefik watches (cc-ci's swarm.nix creates
        `proxy`). When set, a one-container swarm stack `opencode-ui` (a socat TCP relay to
        nginx on the docker bridge) is deployed with traefik labels routing opencodeUiHost on
        the `web-secure` entrypoint — the same label mechanism every cc-ci service and recipe
        uses, so it coexists with the traefik recipe's own file provider (the wildcard cert and
        the `security` middleware live there; switching traefik to a file *directory* replaces
        that file and takes every front door down — learned 2026-09-07). null = no route.
      '';
    };

    opencodeUiHost = lib.mkOption {
      type = lib.types.str;
      default = "oc.commoninternet.net";
      description = "nginx server_name for the opencode web UI (TLS + basic auth).";
    };

  };

  config = {
    # ---- the loops user -------------------------------------------------------------------
    # claude sessions run as non-root (--dangerously-skip-permissions is refused for root).
    users.users.loops = {
      isNormalUser = true;
      uid = 1000;                 # fixed: workspace files are rsynced between hosts by uid
      home = "/home/loops";
      shell = pkgs.bash;
      extraGroups = [ "wheel" "docker" ];
    };
    security.sudo.wheelNeedsPassword = false;
    security.sudo.extraRules = [{
      users = [ "loops" ];
      commands = [{ command = "ALL"; options = [ "NOPASSWD" ]; }];
    }];

    # /home/loops/.local/bin holds the standalone opencode binary; it must be first on every PATH
    # (interactive shells, tmux, the systemd units in cc-ci.nix prepend it too).
    environment.variables.PATH = lib.mkForce
      "/home/loops/.local/bin:/run/current-system/sw/bin:/run/wrappers/bin:/usr/bin:/bin";

    # ---- nix-ld: the standalone opencode CLI is a foreign dynamic ELF binary --------------------
    programs.nix-ld.enable = true;
    programs.nix-ld.libraries = with pkgs; [ stdenv.cc.cc.lib zlib openssl curl glibc ];

    # ---- the toolbox every agent on this box gets ----------------------------------------
    # Bar for adding something: an agent doing ordinary work would otherwise waste a turn
    # discovering it is absent.
    environment.systemPackages = with pkgs; [
      git tmux python3 jq curl cacert
      gnused gawk coreutils gnugrep findutils util-linux nettools openssh
      age sops ssh-to-age
      wget gnutar gzip unzip zip xz
      ripgrep fd tree file less which
      procps psmisc htop lsof strace ncdu
      dnsutils socat netcat-gnu iproute2 iputils
      openssl gnumake gcc pkg-config
      yq-go diffutils patch rsync bubblewrap
    ];

    # ---- ssh config for the loops user: `ssh cc-ci` = the CI server (root) -----------------
    # Written only if absent so a manual customisation survives rebuilds.
    system.activationScripts.loopsSshConfig = ''
      mkdir -p /home/loops/.ssh && chown loops:users /home/loops/.ssh && chmod 700 /home/loops/.ssh
      if [ ! -f /home/loops/.ssh/config ]; then
        cat > /home/loops/.ssh/config <<'SSHCFG'
Host cc-ci
    HostName ${cfg.ciSshHost}
    User root
    IdentityFile /home/loops/.ssh/cc-ci-root-ed25519
    IdentitiesOnly yes
    StrictHostKeyChecking accept-new
    ServerAliveInterval 30

Host git.autonomic.zone
    HostName git.autonomic.zone
    Port 2222
    User git
    IdentityFile /home/loops/.ssh/autonomic-bot-gitea-ed25519
    IdentitiesOnly yes
SSHCFG
        chmod 600 /home/loops/.ssh/config
        chown loops:users /home/loops/.ssh/config
      fi
    '';

    # ---- standalone CLIs (idempotent installers; re-run on every activation, no-op if present) --
    # No Claude Code on this host (operator 2026-09-07): the orchestrator and the weekly upgrader
    # are opencode agents; Claude sessions run on the notplants-orchestrator box and reach this
    # host over ssh.
    systemd.services.opencode-install = {
      description = "Install opencode CLI for loops user (idempotent)";
      wantedBy = [ "multi-user.target" ];
      after = [ "network-online.target" ];
      wants = [ "network-online.target" ];
      serviceConfig = { Type = "oneshot"; RemainAfterExit = true; User = "loops"; Group = "users"; };
      environment = { HOME = "/home/loops"; };
      path = [ pkgs.curl pkgs.bash pkgs.coreutils pkgs.gnutar pkgs.gzip pkgs.unzip ];
      script = ''
        if [ ! -x "$HOME/.local/bin/opencode" ]; then
          echo "installing opencode CLI for loops user..."
          curl -fsSL https://opencode.ai/install | bash || echo "install failed — retry on next activation"
          # The installer puts the binary in ~/.opencode/bin; every unit here expects ~/.local/bin.
          if [ -x "$HOME/.opencode/bin/opencode" ]; then
            mkdir -p "$HOME/.local/bin" && ln -sfn "$HOME/.opencode/bin/opencode" "$HOME/.local/bin/opencode"
          fi
        fi
      '';
    };

    # ---- opencode web server: one shared instance the opencode-backed agents attach to -------
    # Provider creds come from /srv/cc-ci/.testenv (out of band, see README).
    systemd.services.opencode-web = {
      description = "opencode web server for cc-ci agents";
      wantedBy = [ "multi-user.target" ];
      after = [ "network-online.target" "opencode-install.service" ];
      wants = [ "network-online.target" ];
      serviceConfig = {
        Type = "simple";
        User = "loops"; Group = "users";
        WorkingDirectory = "/srv/cc-ci-orch/cc-ci";
        EnvironmentFile = [ "-/srv/cc-ci/cc-ci/.env.public" "/srv/cc-ci/.testenv" ];
        ExecStartPre = "${pkgs.coreutils}/bin/rm -rf /tmp/opencode";
        ExecStart = "/home/loops/.local/bin/opencode serve --hostname 127.0.0.1 --port 4096";
        Restart = "on-failure";
        RestartSec = "5s";
      };
      environment = {
        HOME = "/home/loops";
        PATH = lib.mkForce "/run/wrappers/bin:/home/loops/.local/bin:/run/current-system/sw/bin:/usr/bin:/bin:/etc/profiles/per-user/loops/bin:/nix/var/nix/profiles/default/bin";
      };
      path = [ pkgs.bash pkgs.coreutils pkgs.git pkgs.python3 pkgs.openssh pkgs.tmux pkgs.nettools ];
    };

    # ---- nginx: basic auth for the opencode UI, behind traefik -----------------------------
    # Traefik (public 443, the CI wildcard cert) routes opencodeUiHost to this plain-HTTP vhost
    # on the docker bridge address. nginx enforces HTTP basic auth (the opencode web UI has no
    # auth of its own and can drive agent sessions), and — via real_ip from traefik's
    # X-Forwarded-For — logs the CLIENT address on a 401, which is what the fail2ban jail bans.
    # The htpasswd is created out of band (a store path would be world readable); nginx FAILS TO
    # START without it, and its config check runs as the nginx user:
    #   /etc/nginx/oc-htpasswd   root:nginx 0640   (`oc:<bcrypt>`; plaintext kept in /secrets)
    # Rotate with: printf 'oc:%s\n' "$(mkpasswd -m bcrypt "$P")" > /etc/nginx/oc-htpasswd && systemctl reload nginx
    services.nginx = {
      enable = true;
      recommendedProxySettings = true;
      virtualHosts.${cfg.opencodeUiHost} = {
        listen = [ { addr = "0.0.0.0"; port = cfg.opencodeUiBackendPort; } ];
        basicAuthFile = "/etc/nginx/oc-htpasswd";
        extraConfig = ''
          # traefik sits on the docker networks (ingress 10.0.0.0/24, gwbridge 172.18.0.0/16)
          set_real_ip_from 172.16.0.0/12;
          set_real_ip_from 10.0.0.0/8;
          real_ip_header X-Forwarded-For;
        '';
        locations."/" = {
          proxyPass = "http://127.0.0.1:4096";
          proxyWebsockets = true;
        };
      };
    };
    # Only docker's bridge may reach the plain-HTTP backend; the public interface stays closed.
    networking.firewall.interfaces.docker_gwbridge.allowedTCPPorts = [ cfg.opencodeUiBackendPort ];

    # The traefik side of the route: a swarm service carrying the router labels. It is a plain
    # TCP relay (socat) from the overlay network to nginx on the docker bridge; traefik's
    # X-Forwarded-For passes through untouched, which is what nginx's real_ip reads.
    systemd.services.opencode-ui-route = lib.mkIf (cfg.opencodeUiTraefikNetwork != null) {
      description = "swarm stack opencode-ui: traefik labels ${cfg.opencodeUiHost} -> nginx basic auth";
      wantedBy = [ "multi-user.target" ];
      after = [ "deploy-proxy.service" "docker.service" "nginx.service" ];
      wants = [ "deploy-proxy.service" ];
      path = [ pkgs.docker ];
      serviceConfig = { Type = "oneshot"; RemainAfterExit = true; };
      script = ''
        docker stack deploy --detach=true -c ${pkgs.writeText "opencode-ui-stack.yml" ''
          # Deployed by opencode-ui-route.service (nix/modules/orchestrator-host.nix). Do not edit.
          version: "3.8"
          services:
            relay:
              image: alpine/socat:1.8.0.3
              command: ["TCP-LISTEN:${toString cfg.opencodeUiBackendPort},fork,reuseaddr", "TCP:172.18.0.1:${toString cfg.opencodeUiBackendPort}"]
              networks: [ ${cfg.opencodeUiTraefikNetwork} ]
              deploy:
                replicas: 1
                labels:
                  - "traefik.enable=true"
                  - "traefik.http.routers.opencode-ui.rule=Host(`${cfg.opencodeUiHost}`)"
                  - "traefik.http.routers.opencode-ui.entrypoints=web-secure"
                  - "traefik.http.routers.opencode-ui.tls=true"
                  - "traefik.http.services.opencode-ui.loadbalancer.server.port=${toString cfg.opencodeUiBackendPort}"
          networks:
            ${cfg.opencodeUiTraefikNetwork}:
              external: true
        ''} opencode-ui
      '';
    };
  };
}