Enclose rfid reading

rpi/hardware/rfid/main.py

@@ -0,0 +1,63 @@
+#!/usr/bin/env python3
+from collections.abc import Callable
+from threading import Thread
+import threading
+from serial import Serial
+
+
+class RfidReader:
+
+    __serial : Serial = None
+    __thread : Thread | None = None
+    __listeners : list[Callable] = None
+
+    def __init__(self, port : str, baudrate: int):
+        self.__serial = Serial(port, baudrate)
+        self._run_event = threading.Event()
+        self.__listeners = []
+
+    def start(self) -> None:
+        self._run_event.set()
+        if self.__thread is None or not self.__thread.is_alive():
+            self.__thread = Thread(target=self.__read, daemon=True)
+            self.__thread.start()
+
+    def stop(self) -> None:
+        if self._run_event.is_set():
+            self._run_event.clear()
+
+    def subscribe(self, listener : Callable) -> None:
+        self.__listeners.append(listener)
+
+    def __notify(self, uid : int):
+        for listener in self.__listeners:
+            listener(uid)
+
+    def __read(self):
+        while self._run_event.is_set():
+            data = b""
+            while len(data) < 14 and self._run_event.is_set():
+                character = self.__serial.read(1)
+                if not character: continue
+                data += character
+
+            if len(data) >= 11:
+                hex_value = data[5:11].decode(errors='ignore')
+                try:
+                    res = int(hex_value, 16)
+                    self.__notify(res)
+                except ValueError:
+                    print("Invalid hex:", hex_value)
+            else:
+                print("Received incomplete data:", data)
+
+
+
+if __name__ == "__main__":
+
+    def callback(uid):
+        print("UID:", uid)
+
+    reader = RfidReader("/dev/serial0", 9600)
+    reader.subscribe(callback)
+    reader.start()