import argparse
import logging
from pathlib import Path

from . import (
    Message,
    filter_useless_messages,
    format_messages,
    merge_adjacent_messages,
    parse_messages_in_chat_folder,
)

logger = logging.getLogger(__name__)


def group_messages_by_period(messages: list[Message]) -> dict[str, list[Message]]:
    by_period: dict[str, list[Message]] = {}
    for msg in messages:
        period_key = f'{msg.sent_at.year}-{msg.sent_at.month:02}'
        by_period.setdefault(period_key, []).append(msg)
        del msg
    return by_period


def parse_args():
    parser = argparse.ArgumentParser()
    parser.add_argument('path', type=Path)
    parser.add_argument('--output', type=Path)
    return parser.parse_args()


def main():
    logging.basicConfig()
    logging.getLogger().setLevel('INFO')
    args = parse_args()

    server = args.path.parent.name
    receipient = args.path.name

    all_messages = parse_messages_in_chat_folder(args.path)
    all_messages = filter_useless_messages(all_messages)
    all_messages = merge_adjacent_messages(all_messages)

    messages_by_period = group_messages_by_period(all_messages)

    for period_key, messages in messages_by_period.items():
        output_file = args.output / f'{server} - {receipient} - {period_key}.md'
        logger.info('Writing % 5d messages to %s', len(messages), output_file)
        with open(output_file, 'w') as f:
            f.write(
                format_messages(
                    messages,
                    title=f'{server} - {receipient} - {period_key}',
                ),
            )

        del period_key, messages, output_file


if __name__ == '__main__':
    main()