[companion] Implement schema loading

companion/device.py

 import asyncio
+import json
 
 from kivy.logger import Logger
+from kivy.uix.button import Button
 from kivy.uix.widget import Widget
 
 from bleak import BleakClient
@@ -16,6 +18,8 @@ class DeviceWidget(Widget):
         super().__init__(*args, **kwargs)
 
         self._task_queue = set()
+        self._ready = False
+        self._data = b""
 
         self._client = BleakClient(address)
         Logger.info(f"Connecting to device: {address}")
@@ -35,16 +39,57 @@ class DeviceWidget(Widget):
     def _reading(self, task):
         Logger.debug("Reading UART data now")
         self._task_queue.discard(task)
-        self.send_line('print("Hallo Welt")')
+
+        self._send_data(b"\x01")
 
     def _handle_rx(self, count, data):
         Logger.debug(f"Received: {data}")
+        if not self._ready:
+            if b"raw REPL" in data:
+                self._ready = True
+                self._data = b""
+                self._raw_repl_entered()
+            else:
+                Logger.warn("Unexpected data before raw REPL")
+            return
+
+        if self._data == b"":
+            if not data.startswith(b"OK"):
+                Logger.warn("Unexpected data, exepcted OK marker")
+                return
+
+            data = data[2:]
+
+        self._data += data
+
+        if self._data.endswith(b"\r\n\x04\x04>"):
+            Logger.debug("Found end marker")
+            self._handle_result(self._data[:-5])
+            self._data = b""
+
+    def _handle_result(self, data):
+        Logger.debug(f"Handling result: {data}")
+
+        if data.startswith(b"_mynit_schemas="):
+            Logger.info("Received schema update")
+            schemas = json.loads(data[15:].decode())
+            self._handle_schemas(schemas)
+
+    def _handle_schemas(self, schemas):
+        Logger.debug("Handling schema update")
+
+    def _raw_repl_entered(self):
+        Logger.info("Raw REPL entereed")
+        Logger.debug("Retrieving schema")
+        self.send_command("import ujson; print('_mynit_schemas=' + ujson.dumps(mynit._schemas))")
 
-    def send_line(self, data):
-        if not data.endswith("\r\n"):
-            data += "\r\n"
+    def send_command(self, data):
+        if not data.endswith("\x04"):
+            data += "\x04"
         data = data.encode()
+        self._send_data(data)
 
+    def _send_data(self, data):
         Logger.debug(f"Sending: {data}")
         task = asyncio.create_task(self._client.write_gatt_char(UART_SERVICE_TX_UUID, data))
         self._task_queue.add(task)

companion/device_list.py

@@ -30,7 +30,7 @@ class DeviceListWidget(Widget):
 
     def _scan_finished(self, task):
         self._scan_task = None
-        Logger.info("Scna finished")
+        Logger.info("Scan finished")
 
     def do_connect(self, address):
         Logger.info(f"Connecting to device: {address}")