fix_type_hints.py

#!/usr/bin/env python3
"""Fix Python 3.9 compatibility by replacing | union syntax with Union/Optional."""

import re
from pathlib import Path

def fix_file(filepath: Path) -> bool:
    """Fix type hints in a single file."""
    content = filepath.read_text()
    original = content
    
    # Add Union import if needed
    if ' | ' in content or ': str | ' in content or '-> str | ' in content:
        if 'from typing import' in content:
            # Add Union to existing import
            content = re.sub(
                r'from typing import ([^\n]+)',
                lambda m: f"from typing import {m.group(1)}, Union" if 'Union' not in m.group(1) else m.group(0),
                content
            )
        else:
            # Add new import after docstring
            lines = content.split('\n')
            for i, line in enumerate(lines):
                if line.startswith('"""') and i > 0:
                    # Find end of docstring
                    for j in range(i+1, len(lines)):
                        if '"""' in lines[j]:
                            lines.insert(j+2, '\nfrom typing import Union')
                            content = '\n'.join(lines)
                            break
                    break
    
    # Replace | None with Optional (already imported)
    content = re.sub(r': (\w+) \| None', r': Optional[\1]', content)
    content = re.sub(r'-> (\w+) \| None', r'-> Optional[\1]', content)
    
    # Replace complex types like dict[str, Any] | None
    content = re.sub(r': (dict\[[\w\s,\[\]]+\]) \| None', r': Optional[\1]', content)
    content = re.sub(r'-> (dict\[[\w\s,\[\]]+\]) \| None', r'-> Optional[\1]', content)
    
    # Replace str | Path with Union[str, Path]
    content = re.sub(r': str \| Path', r': Union[str, Path]', content)
    content = re.sub(r'-> str \| Path', r'-> Union[str, Path]', content)
    
    # Replace dict | None with Optional[dict]
    content = re.sub(r': dict \| None', r': Optional[dict]', content)
    content = re.sub(r'-> dict \| None', r'-> Optional[dict]', content)
    
    if content != original:
        filepath.write_text(content)
        print(f"Fixed: {filepath}")
        return True
    return False

def main():
    """Fix all Python files in agentcoach package."""
    fixed_count = 0
    
    for filepath in Path('agentcoach').rglob('*.py'):
        if fix_file(filepath):
            fixed_count += 1
    
    for filepath in Path('tests').rglob('*.py'):
        if fix_file(filepath):
            fixed_count += 1
    
    print(f"\nFixed {fixed_count} files")

if __name__ == '__main__':
    main()