"""Runtime configuration helpers for the MCP server."""
from __future__ import annotations
import os
import shutil
from pathlib import Path
from typing import Final, Optional
from dotenv import load_dotenv
# Load .env file from project root (if it exists)
load_dotenv()
def _parse_bool(value: str | None, *, default: bool = False) -> bool:
if value is None:
return default
value = value.strip().lower()
return value in {"1", "true", "yes", "on"}
def _parse_int(value: str | None, *, default: int) -> int:
if value is None or not value.strip():
return default
try:
return int(value)
except ValueError:
return default
def _env_bool(name: str, *, default: bool = False) -> bool:
return _parse_bool(os.getenv(name), default=default)
def _env_int(name: str, *, default: int) -> int:
return _parse_int(os.getenv(name), default=default)
ENABLE_WRITES: Final[bool] = _env_bool("MCP_ENABLE_WRITES", default=False)
MAX_WRITES_PER_REQUEST: Final[int] = _env_int("MCP_MAX_WRITES_PER_REQUEST", default=2)
MAX_ITEMS_PER_BATCH: Final[int] = _env_int("MCP_MAX_ITEMS_PER_BATCH", default=256)
_audit_log_env = os.getenv("MCP_AUDIT_LOG", "").strip()
AUDIT_LOG_PATH: Final[Optional[Path]] = (
Path(_audit_log_env).expanduser() if _audit_log_env else None
)
def _discover_pdflatex() -> Optional[str]:
"""Auto-discover pdflatex in common locations.
Search order:
1. System PATH (via shutil.which)
2. ~/.local/texlive/*/bin/*/pdflatex (user installations)
3. /usr/local/texlive/*/bin/*/pdflatex (system-wide installations)
Returns the first found executable path, or None if not found.
"""
# Try system PATH first
system_pdflatex = shutil.which("pdflatex")
if system_pdflatex:
return system_pdflatex
# Search in common TeX Live locations
search_roots = [
Path.home() / ".local" / "texlive",
Path("/usr/local/texlive"),
]
for root in search_roots:
if not root.exists():
continue
# Find all pdflatex binaries under this root
# Pattern: texlive/YEAR/bin/ARCH/pdflatex
for year_dir in sorted(root.iterdir(), reverse=True): # newest first
if not year_dir.is_dir():
continue
bin_dir = year_dir / "bin"
if not bin_dir.exists():
continue
for arch_dir in bin_dir.iterdir():
if not arch_dir.is_dir():
continue
pdflatex = arch_dir / "pdflatex"
if pdflatex.is_file() and os.access(pdflatex, os.X_OK):
return str(pdflatex)
return None
def get_pdflatex_path() -> Optional[str]:
"""Get the pdflatex executable path.
Priority:
1. PDFLATEX_PATH environment variable (explicit override)
2. Auto-discovery in common locations
Returns the path as a string, or None if not found.
"""
# Check explicit override first
explicit_path = os.getenv("PDFLATEX_PATH", "").strip()
if explicit_path:
path = Path(explicit_path).expanduser().resolve()
if path.is_file() and os.access(path, os.X_OK):
return str(path)
# If explicitly set but invalid, return it anyway (will fail with clear error)
return explicit_path
# Fall back to auto-discovery
return _discover_pdflatex()
__all__ = [
"AUDIT_LOG_PATH",
"ENABLE_WRITES",
"MAX_ITEMS_PER_BATCH",
"MAX_WRITES_PER_REQUEST",
"get_pdflatex_path",
]
