feat: add record saving

src/record_file.py

@@ -0,0 +1,49 @@
+from pathlib import Path
+import struct
+import time
+from typing import Literal
+
+from src.snapshot import Snapshot
+
+
+class RecordFile:
+    VERSION = 1
+
+    def __init__(self, path: str | Path, mode: Literal["w", "r"]) -> None:
+        self.path: str | Path = path
+        self.mode: Literal["w", "r"] = mode
+        self.file = open(self.path, self.mode + "b")
+
+    def __enter__(self):
+        return self
+
+    def __exit__(self, type, value, traceback):
+        self.file.close()
+
+    def write_header(self, n_snapshots: int):
+        data: bytes = struct.pack(
+            ">IId", self.VERSION, n_snapshots, time.time())
+        self.file.write(data)
+
+    def write_snapshots(self, snapshots: list[Snapshot]):
+        self.write_header(len(snapshots))
+        for snapshot in snapshots:
+            data: bytes = snapshot.pack()
+            self.file.write(struct.pack(">I", len(data)) + data)
+
+    def read_snapshots(self) -> list[Snapshot]:
+        version: int = struct.unpack(">I", self.file.read(4))[0]
+        if version != self.VERSION:
+            raise ValueError(
+                f"Cannot parse record file with format version {version} (current version: {self.VERSION})")
+
+        n_snapshots: int
+        timestamp: float
+        n_snapshots, timestamp = struct.unpack(">Id", self.file.read(12))
+        snapshots: list[Snapshot] = []
+
+        for _ in range(n_snapshots):
+            size: int = struct.unpack(">I", self.file.read(4))[0]
+            snapshots.append(Snapshot.unpack(self.file.read(size)))
+
+        return snapshots

src/recorder.py

@@ -1,11 +1,15 @@
+import os
+from pathlib import Path
 import socket
 import struct
+from typing import Optional
 
 from PyQt6 import uic
 from PyQt6.QtCore import QObject, QThread, QTimer, pyqtSignal, pyqtSlot
 from PyQt6.QtWidgets import QMainWindow
 
 from src.command import CarControl, Command, ControlCommand, RecordingCommand
+from src.record_file import RecordFile
 from src.recorder_ui import Ui_Recorder
 from src.snapshot import Snapshot
 
@@ -84,10 +88,23 @@ class RecorderClient(QObject):
         self.socket.close()
 
 
+class ThreadedSaver(QThread):
+    def __init__(self, path: str | Path, snapshots: list[Snapshot]):
+        super().__init__()
+        self.path: str | Path = path
+        self.snapshots: list[Snapshot] = snapshots
+
+    def run(self):
+        with RecordFile(self.path, "w") as f:
+            f.write_snapshots(self.snapshots)
+
+
 class RecorderWindow(Ui_Recorder, QMainWindow):
     close_signal: pyqtSignal = pyqtSignal()
     send_signal: pyqtSignal = pyqtSignal(object)
 
+    SAVE_DIR: Path = Path(__file__).parent.parent / "records"
+
     def __init__(self, host: str, port: int) -> None:
         super().__init__()
 
@@ -147,9 +164,10 @@ class RecorderWindow(Ui_Recorder, QMainWindow):
 
         self.saveRecordButton.clicked.connect(self.save_record)
 
+        self.saving_worker: Optional[ThreadedSaver] = None
         self.recording = False
 
-        self.recorded_data = []
+        self.snapshots: list[Snapshot] = []
         self.client_thread.start()
 
     def on_car_controlled(self, control: CarControl, active: bool):
@@ -171,12 +189,44 @@ class RecorderWindow(Ui_Recorder, QMainWindow):
         )
 
     def save_record(self):
-        pass
+        if self.saving_worker is not None:
+            print("Already saving !")
+            return
+
+        if len(self.snapshots) == 0:
+            print("No data to save !")
+            return
+
+        if self.recording:
+            self.toggle_record()
+
+        self.saveRecordButton.setText("Saving ...")
+
+        self.SAVE_DIR.mkdir(exist_ok=True)
+
+        record_name: str = "record_%d.rec"
+        fid = 0
+        while os.path.exists(self.SAVE_DIR / (record_name % fid)):
+            fid += 1
+
+        self.saving_worker = ThreadedSaver(
+            self.SAVE_DIR / (record_name % fid), self.snapshots)
+        self.snapshots = []
+        self.nbrSnapshotSaved.setText("0")
+        self.saving_worker.finished.connect(self.on_record_save_done)
+        self.saving_worker.start()
+
+    def on_record_save_done(self):
+        if self.saving_worker is None:
+            return
+        print("Recorded data saved to", self.saving_worker.path)
+        self.saving_worker = None
+        self.saveRecordButton.setText("Save")
 
     @pyqtSlot(Snapshot)
     def on_snapshot_received(self, snapshot: Snapshot):
-        self.recorded_data.append(snapshot)
+        self.snapshots.append(snapshot)
-        self.nbrSnapshotSaved.setText(str(len(self.recorded_data)))
+        self.nbrSnapshotSaved.setText(str(len(self.snapshots)))
 
     def shutdown(self):
         self.close_signal.emit()