"""
System file filtering utilities for cross-platform dataset validation.
Filters out OS-specific files that shouldn't be included in validation.
"""

import os

# System files to ignore during validation
SYSTEM_FILES = {
    # macOS system files
    ".DS_Store",  # Finder metadata
    "._.DS_Store",  # macOS resource fork
    "._*",  # macOS AppleDouble files (pattern)
    ".Spotlight-V100",  # Spotlight search index
    ".Trashes",  # Trash folder
    ".fseventsd",  # File system events daemon
    ".VolumeIcon.icns",  # Volume icon
    # Windows system files
    "Thumbs.db",  # Windows thumbnail cache
    "ehthumbs.db",  # Windows thumbnail cache
    "Desktop.ini",  # Windows folder settings
    "$RECYCLE.BIN",  # Windows recycle bin
    "System Volume Information",  # Windows system folder
    # Linux/Unix system files
    ".directory",  # KDE folder settings
    ".hidden",  # Hidden file list
    # Version control and IDE files
    ".git",  # Git repository
    ".gitignore",  # Git ignore file
    ".svn",  # Subversion
    ".hg",  # Mercurial
    ".idea",  # IntelliJ IDEA
    ".vscode",  # Visual Studio Code
    "__pycache__",  # Python cache
    "*.pyc",  # Python bytecode (pattern)
    ".pytest_cache",  # Pytest cache
    # Temporary files
    ".tmp",  # Temporary files
    ".TemporaryItems",  # macOS temporary items
    "~*",  # Backup files (pattern)
    "#*#",  # Emacs temp files (pattern)
    ".#*",  # Emacs lock files (pattern)
}

# Patterns that need special matching (contain wildcards)
SYSTEM_FILE_PATTERNS = {
    "._*",  # macOS AppleDouble files
    "*.pyc",  # Python bytecode
    "~*",  # Backup files
    "#*#",  # Emacs temp files
    ".#*",  # Emacs lock files
}


def is_system_file(filename):
    """
    Check if a filename is a system file that should be ignored during validation.

    Args:
        filename (str): The filename to check

    Returns:
        bool: True if the file should be ignored, False otherwise
    """
    if not filename:
        return True

    # Check exact matches
    if filename in SYSTEM_FILES:
        return True

    # Check patterns
    import fnmatch

    for pattern in SYSTEM_FILE_PATTERNS:
        if fnmatch.fnmatch(filename, pattern):
            return True

    return False


def filter_system_files(file_list):
    """
    Filter out system files from a list of filenames.

    Args:
        file_list (list): List of filenames

    Returns:
        list: Filtered list with system files removed
    """
    return [f for f in file_list if not is_system_file(f)]


def should_validate_file(file_path):
    """
    Check if a file should be included in dataset validation.

    Args:
        file_path (str): Full or relative path to the file

    Returns:
        bool: True if file should be validated, False if it should be skipped
    """
    filename = os.path.basename(file_path)
    return not is_system_file(filename)


def get_ignored_files_summary(file_list):
    """
    Get a summary of which system files were ignored.

    Args:
        file_list (list): Original list of filenames

    Returns:
        dict: Summary with counts and examples of ignored files
    """
    ignored = [f for f in file_list if is_system_file(f)]

    summary = {
        "total_ignored": len(ignored),
        "files": ignored[:10],  # Show first 10 as examples
        "has_more": len(ignored) > 10,
    }

    return summary