From fa31227cff96a170be76508da63f3c64bf635212 Mon Sep 17 00:00:00 2001
From: Sweetbread <sweetbread@coders-squad.com>
Date: Thu, 5 Sep 2024 18:22:38 +0300
Subject: [PATCH] feat: Shutdown on lan

---
 nixos/modules/bundle.nix          |  1 +
 nixos/modules/shutdown-on-lan.nix | 70 +++++++++++++++++++++++++++++++
 2 files changed, 71 insertions(+)
 create mode 100644 nixos/modules/shutdown-on-lan.nix

diff --git a/nixos/modules/bundle.nix b/nixos/modules/bundle.nix
index fd2d104..23efd00 100644
--- a/nixos/modules/bundle.nix
+++ b/nixos/modules/bundle.nix
@@ -13,5 +13,6 @@
     ./vpn.nix
     ./printing.nix
     ./adb.nix
+    ./shutdown-on-lan.nix
   ];
 }
diff --git a/nixos/modules/shutdown-on-lan.nix b/nixos/modules/shutdown-on-lan.nix
new file mode 100644
index 0000000..421b4c5
--- /dev/null
+++ b/nixos/modules/shutdown-on-lan.nix
@@ -0,0 +1,70 @@
+{ pkgs, lib, ... }:
+  let
+    sol = pkgs.writers.writePython3 "shutdown-on-lan.py" {
+      libraries = [ pkgs.python312Packages.psutil ];
+      flakeIgnore = [ "E501" "E302" "E305" ];
+    } /*py*/ ''
+      # https://habr.com/ru/articles/816765/
+
+      import socket
+      import os
+      import logging
+      import psutil
+      from time import sleep
+
+      WOL_PORT = 9
+
+      logging.basicConfig(format='%(levelname)s: %(asctime)s %(message)s', level=logging.INFO)
+      logger = logging.getLogger(__name__)
+
+      def get_ip_mac_address() -> tuple:
+          ip_addr = mac_addr = None
+
+          while not ip_addr or not mac_addr or ip_addr == '127.0.0.1':
+              net = psutil.net_if_addrs()
+              for item in net[list(net.keys())[-1]]:
+                  addr = item.address
+                  # В IPv4-адресах разделители - точки
+                  if '.' in addr:
+                      ip_addr = addr
+                  # В MAC-адресах разделители либо тире, либо одинарное двоеточие.
+                  # Двойное двоеточие - это разделители для адресов IPv6
+                  elif ('-' in addr or ':' in addr) and '::' not in addr:
+                      # Приводим MAC-адрес к одному формату. Формат может меняться в зависимости от ОС
+                      mac_addr = addr.replace(':', '-').upper()
+              if not ip_addr or not mac_addr or ip_addr == '127.0.0.1':
+                  logger.debug('Не удалось получить IP или MAC-адрес сетевого интерфейса')
+                  sleep(10)
+          return ip_addr, mac_addr
+
+      def assemble_wol_packet(mac_address: str) -> str:
+          return f'{"FF-" * 6}{(mac_address + "-") * 16}'
+
+      def check_is_wol_packet(raw_bytes: bytes, assembled_wol_packet: str) -> int:
+          return '-'.join(f'{byte:02x}' for byte in raw_bytes).upper() + '-' == assembled_wol_packet
+    
+      def run_udp_port_listener(port: int):
+          ip_addr, mac_addr = get_ip_mac_address()
+          server_socket = socket.socket(socket.AF_INET, socket.SOCK_DGRAM)
+          server_socket.bind((ip_addr, port))
+          logger.info(f'Listening on {ip_addr}:{port}')
+          assembled_wol_packet = assemble_wol_packet(mac_addr)
+          while True:
+              data, _ = server_socket.recvfrom(1024)
+              if check_is_wol_packet(data, assembled_wol_packet):
+                  if os.name == 'posix':
+                      os.system('shutdown -h now')
+                  elif os.name == 'nt':
+                      os.system('shutdown -s -t 0 -f')
+      run_udp_port_listener(WOL_PORT)
+    '';
+  in {
+    systemd.services.shutdown-on-lan = {
+      enable = true;
+      after = [ "network.target" ];
+      wantedBy = [ "default.target" ];
+      serviceConfig.ExecStart = sol;
+    };
+
+    networking.firewall.allowedUDPPorts = [ 9 ];
+  }