from decimal import Decimal, ROUND_DOWN, InvalidOperation


def normalize_coordinate(value, max_digits, decimal_places):
    """Normalize coordinate to have exactly 6 decimal places"""
    try:
        if value is None:
            return None
            
        # Convert to Decimal for precise handling
        value = Decimal(str(value))
        # Round to exactly 6 decimal places
        value = value.quantize(Decimal('0.000001'), rounding=ROUND_DOWN)
        
        return float(value)
    except (TypeError, ValueError, InvalidOperation):
        return None


def get_english_name(tags):
    """Extract English name from OSM tags, falling back to default name"""
    # Try name:en first
    if 'name:en' in tags:
        return tags['name:en']
    # Then try int_name (international name)
    if 'int_name' in tags:
        return tags['int_name']
    # Fall back to default name
    return tags.get('name')


def normalize_osm_result(result):
    """Normalize OpenStreetMap result to use English names and normalized coordinates"""
    # Normalize coordinates
    result['lat'] = normalize_coordinate(float(result['lat']), 9, 6)
    result['lon'] = normalize_coordinate(float(result['lon']), 10, 6)

    # Get address details
    address = result.get('address', {})

    # Normalize place names to English where possible
    if 'namedetails' in result:
        # For main display name
        result['display_name'] = get_english_name(result['namedetails'])
        
        # For address components
        if 'city' in address and 'city_tags' in result:
            address['city'] = get_english_name(result['city_tags'])
        if 'state' in address and 'state_tags' in result:
            address['state'] = get_english_name(result['state_tags'])
        if 'country' in address and 'country_tags' in result:
            address['country'] = get_english_name(result['country_tags'])

    result['address'] = address
    return result