import os
import sys
import shutil
import datetime

def create_snapshot(file_path):
    """
    Creates a timestamped backup of the given file in .hmcmkit/backups/
    """
    if not os.path.exists(file_path):
        print(f"❌ Error: File not found: {file_path}")
        return None

    # Determine paths
    hmcmkit_root = ".hmcmkit"
    backup_dir = os.path.join(hmcmkit_root, "backups")
    os.makedirs(backup_dir, exist_ok=True)

    # Generate timestamped name
    timestamp = datetime.datetime.now().strftime("%Y%m%d_%H%M%S")
    filename = os.path.basename(file_path)
    backup_name = f"{timestamp}_{filename}"
    backup_path = os.path.join(backup_dir, backup_name)

    try:
        shutil.copy2(file_path, backup_path)
        print(f"📦 Snapshot created: {backup_path}")
        return backup_path
    except Exception as e:
        print(f"❌ Snapshot failed: {e}")
        return None

if __name__ == "__main__":
    if len(sys.argv) < 2:
        print("Usage: python snapshot.py <file_path>")
        sys.exit(1)
        
    create_snapshot(sys.argv[1])