Coverage for src / lilbee / core / system.py: 100%

1"""OS, environment, and platform helpers for lilbee.""" 

2 

3import os 

4import sys 

5from pathlib import Path 

6 

7#: Directory name for a project-local lilbee knowledge base (sibling of ``.git/``). 

8LOCAL_ROOT_DIRNAME = ".lilbee" 

9 

10 

11def default_data_dir() -> Path: 

12 """Return platform-appropriate data directory. 

13 - macOS: ~/Library/Application Support/lilbee 

14 - Windows: %LOCALAPPDATA%/lilbee 

15 - Linux: ~/.local/share/lilbee (XDG_DATA_HOME) 

16 """ 

17 if sys.platform == "darwin": 

18 base = Path.home() / "Library" / "Application Support" 

19 elif sys.platform == "win32": 

20 base = Path(os.environ.get("LOCALAPPDATA", Path.home() / "AppData" / "Local")) 

21 else: 

22 base = Path(os.environ.get("XDG_DATA_HOME", Path.home() / ".local" / "share")) 

23 return base / "lilbee" 

24 

25 

26def find_local_root(start: Path | None = None) -> Path | None: 

27 """Walk up from start (default: cwd) looking for a ``.lilbee/`` directory.""" 

28 start = start or Path.cwd() 

29 for candidate in (start, *start.parents): 

30 marker = candidate / LOCAL_ROOT_DIRNAME 

31 if marker.is_dir(): 

32 return marker 

33 return None 

34 

35 

36def canonical_models_dir() -> Path: 

37 """Return the shared models directory (always in the platform default, never per-project). 

38 Multiple lilbee instances share this directory so models are downloaded once. 

39 """ 

40 return default_data_dir() / "models" 

41 

42 

43def is_ignored_dir(name: str, ignore_dirs: frozenset[str]) -> bool: 

44 """Return True if a directory name should be skipped during traversal.""" 

45 return name.startswith(".") or name in ignore_dirs or name.endswith(".egg-info") 

46 

47 

48_CTX_TIER_FLOOR = 8192 

49_CTX_TIER_TABLE: tuple[tuple[int, int], ...] = ( 

50 # (total_bytes_threshold, target) 

51 (64 * 1024**3, 24576), 

52 (32 * 1024**3, 16384), 

53 (16 * 1024**3, 12288), 

54) 

55 

56 

57def chat_ctx_target_for_total_bytes(total_bytes: int) -> int: 

58 """Pick a chat_n_ctx_target from total host RAM (floor 8192, tiers at 16/32/64 GiB).""" 

59 if total_bytes <= 0: 

60 return _CTX_TIER_FLOOR 

61 for threshold, target in _CTX_TIER_TABLE: 

62 if total_bytes >= threshold: 

63 return target 

64 return _CTX_TIER_FLOOR 

65 

66 

67def _read_total_memory_bytes() -> int: 

68 """Total system RAM in bytes, or 0 when introspection is unavailable.""" 

69 try: 

70 import psutil 

71 

72 return int(psutil.virtual_memory().total) 

73 except Exception: 

74 # psutil import or platform read failed; the caller falls back to the floor. 

75 return 0 

76 

77 

78def scaled_chat_ctx_target_default() -> int: 

79 """Pick a chat_n_ctx_target from this host's total RAM at config-load time.""" 

80 return chat_ctx_target_for_total_bytes(_read_total_memory_bytes())