Begin rewrite

biogascontrollerapp/lib/com.py

@@ -0,0 +1,80 @@
+from typing import Optional
+import serial
+import struct
+import serial.tools.list_ports
+
+
+class Com:
+    def __init__(self, filters: Optional[list[str]] = None) -> None:
+        self._serial: Optional[serial.Serial] = None
+        self._filters = filters if filters != None else [ 'USB-Serial Controller', 'Prolific USB-Serial Controller' ]
+        self._port_override = ''
+
+    def set_port_override(self, override: str) -> None:
+        """Set the port override, to disable port search"""
+        self._port_override = override
+
+    def get_comport(self) -> str:
+        """Find the comport the microcontroller has attached to"""
+        if self._port_override != '':
+            return self._port_override
+
+        # Catch all errors and simply return an empty string if search unsuccessful
+        try:
+            # Get an array of all used comports
+            ports = [comport.device for comport in serial.tools.list_ports.comports()]
+
+            # Filter for specific controller
+            for comport in ports:
+                for filter in self._filters:
+                    if ( filter in comport ):
+                        return comport
+        except:
+            pass
+
+        return ''
+
+    def connect(self, baud_rate: int, port_override: Optional[str] = None) -> bool:
+        """Try to find a comport and connect to the microcontroller. Returns the success as a boolean"""
+        comport = self.get_comport()
+
+        # Comport search returns empty string if search unsuccessful
+        if comport == '':
+            try:
+                self._serial = serial.Serial(comport, baud_rate, timeout=5)
+            except:
+                return False
+            return True
+        else:
+            return False
+
+    def close(self) -> None:
+        """Close the serial connection, if possible"""
+        if self._serial != None:
+            try:
+                self._serial.close()
+            except:
+                pass
+
+    def receive(self, byte_count: int) -> bytes:
+        """Recieve bytes from microcontroller over serial. Returns bytes. Might want to decode using functions from lib.tools"""
+        if self._serial == None:
+            self.connect(19200)
+        if self._serial != None:
+            return self._serial.read(byte_count)
+        else:
+            raise Exception('ERR_CONNECTION')
+
+    def send(self, msg: str) -> None:
+        """Send a string over serial connection."""
+        if self._serial == None:
+            self.connect(19200)
+        if self._serial != None:
+            self._serial.write(msg.encode())
+
+    def send_float(self, msg: float) -> None:
+        """Send a float number over serial connection"""
+        if self._serial == None:
+            self.connect(19200)
+        if self._serial != None:
+            self._serial.write(bytearray(struct.pack('>f', msg))[0:3])