import os
import sys
import re

def audit_file(filepath):
    with open(filepath, 'r', encoding='utf-8') as f:
        content = f.read()

    lines = content.split('\n')
    errors = []

    # 1. Check header
    header_found = False
    for i, line in enumerate(lines[:10]):
        if line.startswith('//! **File:**') or line.startswith('//! MIT License'):
            header_found = True
            break
    
    if not header_found and not filepath.endswith('mod.rs'):
        errors.append("Missing or invalid `//!` header block.")

    # 2. Check function length and blank lines
    in_function = False
    func_start = 0
    func_name = ""
    brace_level = 0
    blank_lines_in_func = []
    inline_comment_count = 0

    for i, line in enumerate(lines):
        stripped = line.strip()

        # Check inline comments
        if '//' in line and not line.lstrip().startswith('//!'):
            if not line.lstrip().startswith('///'):
                inline_comment_count += 1

        if not in_function:
            if stripped.startswith("fn ") or stripped.startswith("pub fn ") or " fn " in stripped:
                in_function = True
                func_start = i
                func_name = stripped.split("fn ")[1].split("(")[0].strip()
                brace_level += stripped.count('{') - stripped.count('}')
        else:
            brace_level += stripped.count('{') - stripped.count('}')
            
            if stripped == "":
                blank_lines_in_func.append(i + 1)
            
            if brace_level == 0:
                in_function = False
                func_len = i - func_start + 1
                if func_len > 8:
                    errors.append(f"Function `{func_name}` exceeds 8 lines (length: {func_len}, lines {func_start+1}-{i+1}).")
                if blank_lines_in_func:
                    errors.append(f"Function `{func_name}` contains blank lines at: {blank_lines_in_func}")
                blank_lines_in_func = []

    if inline_comment_count == 0 and not filepath.endswith('mod.rs'):
        errors.append("File contains 0 inline (`//`) comments. Must have logic explanations.")

    return errors

def main(directory):
    total_errors = 0
    for root, _, files in os.walk(directory):
        if 'target' in root or '.git' in root:
            continue
        for file in files:
            if file.endswith('.rs'):
                filepath = os.path.join(root, file)
                errors = audit_file(filepath)
                if errors:
                    print(f"\n[FAIL] {filepath}")
                    for err in errors:
                        print(f"  - {err}")
                        total_errors += 1
                else:
                    print(f"[PASS] {filepath}")

    if total_errors > 0:
        sys.exit(1)

if __name__ == "__main__":
    if len(sys.argv) < 2:
        print("Usage: python auditor.py <directory>")
        sys.exit(1)
    main(sys.argv[1])