#!/usr/bin/env python3
"""
Quick utility: count function definitions in Python files.
Extracts function names and counts, outputs JSON report.
"""

import ast
import json
import os
import sys
from pathlib import Path
from collections import Counter
from typing import Dict, List, Any


def extract_functions(filepath: str) -> List[str]:
    """Extract function names from a Python file using AST parsing."""
    try:
        with open(filepath, 'r', encoding='utf-8') as f:
            content = f.read()
        tree = ast.parse(content, filename=filepath)
        functions = []
        for node in ast.walk(tree):
            if isinstance(node, ast.FunctionDef):
                functions.append(node.name)
            elif isinstance(node, ast.AsyncFunctionDef):
                functions.append(node.name)
        return functions
    except (SyntaxError, UnicodeDecodeError, FileNotFoundError) as e:
        return []


def scan_directory(directory: str, extensions: List[str] = None) -> Dict[str, Any]:
    """Scan a directory for Python files and extract function counts."""
    if extensions is None:
        extensions = ['.py']
    
    all_functions = []
    files_scanned = 0
    
    for root, dirs, files in os.walk(directory):
        for filename in files:
            if any(filename.endswith(ext) for ext in extensions):
                filepath = os.path.join(root, filename)
                functions = extract_functions(filepath)
                if functions:
                    all_functions.extend(functions)
                    for func in functions:
                        print(f"{filepath}: {func}")
                files_scanned += 1
    
    function_counts = Counter(all_functions)
    
    return {
        "directory": directory,
        "files_scanned": files_scanned,
        "total_function_definitions": len(all_functions),
        "unique_functions": len(function_counts),
        "top_functions": dict(function_counts.most_common(10))
    }


if __name__ == "__main__":
    target = sys.argv[1] if len(sys.argv) > 1 else "/root"
    
    result = scan_directory(target)
    print("\n--- REPORT ---")
    print(json.dumps(result, indent=2))