{
  config,
  lib,
  pkgs,
  xlib,
  ...
}:
# SNI-fronted reverse proxy (vds/nginx.nix style): port 443 is owned by an
# nginx stream block that reads the ClientHello SNI and forwards the raw
# TLS stream. The HTTP vhosts no longer bind 443 — they listen on an
# internal HTTPS listener (127.0.0.1:8443) that the stream forwards onto,
# so all existing services behave exactly as before.
#
# Routing:
#   x.zeroq.su        → 127.0.0.1:2049   (3x-ui controller panel; TLS is
#                       terminated inside the container by the mounted LE
#                       cert, exactly like pubray1.zeroq.su on the VDS)
#   immich/git/...    → 127.0.0.1:8443   (nginx's own http {} listener:
#                       TLS termination + proxyPass unchanged)
#   default           → 127.0.0.1:15380  (Xray REALITY; podman DNATs
#                       host:15380 → container:443 so Xray sees its real
#                       configured port 443)
#
# ssl_preread reads SNI from the ClientHello; every SNI matching a known
# vhost goes to the internal web listener, x.zeroq.su goes to the panel,
# and anything else (REALITY fronting domains, direct-IP) goes to Xray.
let
  server = "192.168.1.20";

  panelDomain = "x.zeroq.su";
  # Replaces the default 443 binding for every public vhost: 443 now
  # belongs to the stream block, the internal https listener hosts the
  # real server blocks. Port 80 stays public for ACME http-01 + redirects.
  webListen = [
    {
      addr = "0.0.0.0";
      port = 80;
    }
    {
      addr = "127.0.0.1";
      port = 8443;
      ssl = true;
    }
  ];

  mkProxy =
    {
      domain,
      port,
      addSSL ? false,
      extraConfig ? "",
    }:
    {
      name = domain;
      value = {
        enableACME = true;
        listen = webListen;
        locations."/" = {
          proxyPass = "http://${server}:${toString port}";
          proxyWebsockets = true;
        };
      }
      // lib.optionalAttrs (!addSSL) { forceSSL = true; }
      // lib.optionalAttrs addSSL { addSSL = true; }
      // lib.optionalAttrs (extraConfig != "") { inherit extraConfig; };
    };

  bigUploads = "client_max_body_size 5G;";

  sites = [
    {
      domain = "immich.zeroq.su";
      port = 2283;
      addSSL = true;
      extraConfig = bigUploads;
    }
    {
      domain = "kuma.zeroq.su";
      port = 4001;
    }
    {
      domain = "health.zeroq.su";
      port = 19999;
    }
    {
      domain = "git.zeroq.su";
      port = 3000;
    }
    {
      domain = "homebox.zeroq.su";
      port = 7745;
    }
    {
      domain = "flux.zeroq.su";
      port = 6061;
    }
    {
      domain = "navidrome.zeroq.su";
      port = 4533;
      addSSL = true;
    }
    {
      domain = "calibre.zeroq.su";
      port = 8083;
      extraConfig = bigUploads;
    }
    {
      domain = "nix-cache.zeroq.su";
      port = 5000;
      extraConfig = bigUploads;
    }
    {
      domain = "pdf.zeroq.su";
      port = 8446;
      extraConfig = bigUploads;
    }
  ];

  # Hardcoded vhosts served by the internal web listener (next to `sites`).
  # Every one of them must appear in the SNI map → web.
  extraWebDomains = [
    "office.zeroq.su"
    "zeroq.su"
    "vetymae.opencodes.zeroq.su"
    "lamet.opencodes.zeroq.su"
    "nextcloud.zeroq.su"
  ];

  # Goes inside the auto-generated `stream {}` block (services.nginx.streamConfig).
  # x.zeroq.su → 3x-ui panel; known vhosts → nginx's own https listener;
  # everything else (any SNI a REALITY client uses, e.g.
  # media.mediavitrina.ru, or direct-IP) → Xray.
  streamConfig = ''
    ssl_preread on;

    map $ssl_preread_server_name $sni_backend {
      default               xray;
      ${panelDomain}        panel;
      ${"\n" + lib.concatMapStringsSep "\n" (d: "      ${d} web;") (extraWebDomains ++ (map (s: s.domain) sites))}
    }

    upstream panel {
      server 127.0.0.1:2049;
    }

    upstream web {
      server 127.0.0.1:8443;
    }

    upstream xray {
      server 127.0.0.1:15380;
    }

    server {
      listen 443;
      proxy_pass $sni_backend;
      proxy_timeout 600s;
      proxy_connect_timeout 5s;
    }
  '';
in
{
  services.nginx = {
    enable = true;
    recommendedGzipSettings = true;
    recommendedOptimisation = true;
    recommendedProxySettings = true;
    recommendedTlsSettings = true;
    # Lands inside the auto-generated `stream {}` block.
    streamConfig = streamConfig;
    virtualHosts = (builtins.listToAttrs (map mkProxy sites)) // {
      "nextcloud.private" = {
        forceSSL = false;
        enableACME = false;
        listen = [
          {
            addr = "100.64.0.0";
            port = 10000;
          }
          {
            addr = "192.168.1.20";
            port = 10000;
          }
          {
            addr = "127.0.0.1";
            port = 10000;
          }
        ];
      };
      "office.zeroq.su" = {
        forceSSL = true;
        enableACME = true;
        listen = webListen;
      };
      "pdf.private" = {
        forceSSL = false;
        enableACME = false;
        listen = [
          {
            addr = "0.0.0.0";
            port = 80;
          }
          {
            addr = "100.64.0.0";
            port = 8446;
          }
          {
            addr = "192.168.1.20";
            port = 8446;
          }
          {
            addr = "127.0.0.1";
            port = 8446;
          }
        ];
        extraConfig = bigUploads;
      };
      "x.zeroq.su" = {
        # ACME only — no https listener here: 443 is owned by the stream
        # block, which routes the x.zeroq.su SNI to the panel inside the
        # container (127.0.0.1:2049). 3x-ui terminates TLS itself using
        # the cert this vhost renews (mounted at /root/cert/), and serves
        # /subs/, /subsjs/, /clash/ straight from the panel, like the VDS.
        # Don't add forceSSL: it would generate an HTTPS server block that
        # conflicts with the stream listener.
        enableACME = true;
      };
      "zeroq.su" = {
        forceSSL = true;
        enableACME = true;
        listen = webListen;
        root = pkgs.writeTextDir "index.html" ''
          <!doctype html>
          <html>
          <body>
            <pre>What are you doing here?</pre>
          </body>
          </html>
        '';
        locations."/guest/" = {
          proxyPass = "http://${server}:80";
          proxyWebsockets = true;
        };
      };
      "vetymae.opencodes.zeroq.su" = {
        forceSSL = true;
        enableACME = true;
        listen = webListen;
        locations."/" = {
          proxyPass = "http://100.86.62.4:4096";
          proxyWebsockets = true;
        };
      };
      "lamet.opencodes.zeroq.su" = {
        forceSSL = true;
        enableACME = true;
        listen = webListen;
        locations."/" = {
          proxyPass = "http://100.106.21.39:6061";
          proxyWebsockets = true;
        };
      };
      "nextcloud.zeroq.su" = {
        forceSSL = true;
        enableACME = true;
        listen = webListen;
        locations = {
          "/" = {
            proxyPass = "http://${server}:10000";
            proxyWebsockets = true;
          };
          "/whiteboard" = {
            proxyPass = "http://${server}:3002";
            proxyWebsockets = true;
          };
        };
        extraConfig = bigUploads;
      };
    };
  };
  networking.firewall.allowedTCPPorts = [
    80
    443
  ];
}