Technician tool v0.1

Imported from the Google Drive folder 004-technician_tool/v0.1.

kota_tech/core/session.py

@@ -0,0 +1,39 @@
+"""Per-connection session log on disk (already redacted lines only)."""
+
+from __future__ import annotations
+
+import datetime as dt
+import re
+from pathlib import Path
+
+from .logline import LogLine
+
+SESSIONS_DIR = Path.home() / "KotaTechnicianTool" / "sessions"
+
+
+class SessionLog:
+    def __init__(self, root: Path = SESSIONS_DIR):
+        self.root = root
+        self.path: Path | None = None
+        self._fh = None
+
+    def start(self, device_hint: str) -> Path:
+        self.stop()
+        self.root.mkdir(parents=True, exist_ok=True)
+        stamp = dt.datetime.now().strftime("%Y%m%d_%H%M%S")
+        safe = re.sub(r"[^A-Za-z0-9]+", "", device_hint)[:20] or "board"
+        self.path = self.root / f"session_{stamp}_{safe}.log"
+        self._fh = self.path.open("a", encoding="utf-8", newline="\n")
+        return self.path
+
+    def write(self, line: LogLine) -> None:
+        if self._fh is None:
+            return
+        ts = dt.datetime.fromtimestamp(line.host_time).strftime("%H:%M:%S.%f")[:-3]
+        self._fh.write(f"[{ts}] {line.text}\n")
+        self._fh.flush()
+
+    def stop(self) -> None:
+        if self._fh is not None:
+            self._fh.close()
+            self._fh = None