feat: Add tool contract validation mechanism

lib/logger.py

@@ -0,0 +1,118 @@
+"""Unified logging system for OpenMontage.
+
+Provides a consistent logging interface across the entire project with:
+- Multiple log levels (DEBUG, INFO, WARNING, ERROR, CRITICAL)
+- Console and optional file logging
+- Structured log format
+- Verbose mode support
+"""
+
+from __future__ import annotations
+
+import logging
+import sys
+from pathlib import Path
+from typing import Optional, Union
+
+
+# Global logger instance
+_logger: Optional[logging.Logger] = None
+
+
+def setup_logger(
+    name: str = "openmontage",
+    level: Union[int, str] = logging.INFO,
+    log_file: Optional[Path] = None,
+    verbose: bool = False,
+) -> logging.Logger:
+    """Setup and return a configured logger.
+
+    Args:
+        name: Logger name
+        level: Logging level
+        log_file: Optional log file path
+        verbose: If True, set DEBUG level
+
+    Returns:
+        Configured logger instance
+    """
+    global _logger
+
+    # Return existing logger if already configured
+    if _logger is not None and _logger.name == name:
+        return _logger
+
+    # Create logger
+    logger = logging.getLogger(name)
+
+    # Clear existing handlers to avoid duplication
+    if logger.handlers:
+        logger.handlers.clear()
+
+    # Set level
+    if verbose:
+        level = logging.DEBUG
+    elif isinstance(level, str):
+        level = getattr(logging, level.upper(), logging.INFO)
+
+    logger.setLevel(level)
+
+    # Log format
+    formatter = logging.Formatter(
+        "%(asctime)s - %(name)s - %(levelname)s - %(message)s",
+        datefmt="%Y-%m-%d %H:%M:%S"
+    )
+
+    # Console handler
+    console_handler = logging.StreamHandler(sys.stdout)
+    console_handler.setFormatter(formatter)
+    logger.addHandler(console_handler)
+
+    # File handler (if provided)
+    if log_file:
+        # Ensure parent directory exists
+        log_file.parent.mkdir(parents=True, exist_ok=True)
+        file_handler = logging.FileHandler(log_file, encoding="utf-8")
+        file_handler.setFormatter(formatter)
+        logger.addHandler(file_handler)
+
+    _logger = logger
+    return logger
+
+
+def get_logger() -> logging.Logger:
+    """Get or create the global OpenMontage logger.
+
+    Returns:
+        The global logger instance
+    """
+    global _logger
+    if _logger is None:
+        _logger = setup_logger()
+    return _logger
+
+
+# Convenience functions for quick logging
+def debug(msg: str, *args, **kwargs) -> None:
+    """Log a debug message."""
+    get_logger().debug(msg, *args, **kwargs)
+
+
+def info(msg: str, *args, **kwargs) -> None:
+    """Log an info message."""
+    get_logger().info(msg, *args, **kwargs)
+
+
+def warning(msg: str, *args, **kwargs) -> None:
+    """Log a warning message."""
+    get_logger().warning(msg, *args, **kwargs)
+
+
+def error(msg: str, *args, **kwargs) -> None:
+    """Log an error message."""
+    get_logger().error(msg, *args, **kwargs)
+
+
+def critical(msg: str, *args, **kwargs) -> None:
+    """Log a critical message."""
+    get_logger().critical(msg, *args, **kwargs)