#!/usr/bin/env python3
"""Quick Python file statistics reporter.
Usage: python py_stats.py <directory> [output_file]
Reports: number of .py files, total lines, imports, functions, classes.
"""
import os
import sys
import ast
from pathlib import Path

def analyze_py_file(filepath):
    """Analyze a single Python file."""
    result = {
        'lines': 0,
        'imports': 0,
        'functions': 0,
        'classes': 0
    }
    
    try:
        with open(filepath, 'r', encoding='utf-8') as f:
            content = f.read()
            result['lines'] = len(content.splitlines())
            
        tree = ast.parse(content)
        for node in ast.walk(tree):
            if isinstance(node, (ast.Import, ast.ImportFrom)):
                result['imports'] += 1
            elif isinstance(node, (ast.FunctionDef, ast.AsyncFunctionDef)):
                result['functions'] += 1
            elif isinstance(node, ast.ClassDef):
                result['classes'] += 1
    except Exception as e:
        result['error'] = str(e)
    
    return result

def scan_directory(directory):
    """Scan directory for Python files and report statistics."""
    stats = {
        'files': 0,
        'total_lines': 0,
        'total_imports': 0,
        'total_functions': 0,
        'total_classes': 0,
        'file_details': []
    }
    
    for root, dirs, files in os.walk(directory):
        # Skip hidden directories and common non-source folders
        dirs[:] = [d for d in dirs if not d.startswith('.') and d not in ('__pycache__', 'venv', '.venv', 'node_modules')]
        
        for file in files:
            if file.endswith('.py'):
                filepath = os.path.join(root, file)
                relpath = os.path.relpath(filepath, directory)
                fstats = analyze_py_file(filepath)
                fstats['path'] = relpath
                stats['file_details'].append(fstats)
                stats['files'] += 1
                stats['total_lines'] += fstats['lines']
                stats['total_imports'] += fstats['imports']
                stats['total_functions'] += fstats['functions']
                stats['total_classes'] += fstats['classes']
    
    return stats

def main():
    if len(sys.argv) < 2:
        print("Usage: python py_stats.py <directory> [output_file]")
        sys.exit(1)
    
    directory = sys.argv[1]
    output_file = sys.argv[2] if len(sys.argv) > 2 else None
    
    if not os.path.isdir(directory):
        print(f"Error: {directory} is not a directory")
        sys.exit(1)
    
    stats = scan_directory(directory)
    
    output = []
    output.append(f"Python File Statistics for: {directory}")
    output.append("=" * 50)
    output.append(f"Total .py files: {stats['files']}")
    output.append(f"Total lines: {stats['total_lines']}")
    output.append(f"Total imports: {stats['total_imports']}")
    output.append(f"Total functions: {stats['total_functions']}")
    output.append(f"Total classes: {stats['total_classes']}")
    output.append("")
    
    if stats['files'] <= 20:  # Show details for small projects
        output.append("File details:")
        output.append("-" * 50)
        for f in stats['file_details']:
            output.append(f"  {f['path']}: {f['lines']} lines, {f['imports']} imports, {f['functions']} funcs, {f['classes']} classes")
    
    result = "\n".join(output)
    print(result)
    
    if output_file:
        with open(output_file, 'w') as f:
            f.write(result)
        print(f"\nResults written to: {output_file}")

if __name__ == '__main__':
    main()