import dataclasses
import re
import datetime
from pathlib import Path
import bs4

@dataclasses.dataclass(frozen=True, order=True)
class Message:
    sent_at: datetime.datetime
    sender: str
    text: str

    def __post_init__(self):
        assert self.sent_at is not None
        assert self.sender is not None
        assert self.text is not None

def datetime_sent(chat_start: datetime.datetime, message_sent: datetime.time) -> datetime.datetime:
    naive = datetime.datetime.combine(chat_start.date(), message_sent, chat_start.tzinfo)
    if chat_start.time() > message_sent:
        naive = naive - datetime.timedelta(days=1)
    return naive


def parse_messages_in_chat_file(path: Path) -> list[Message]:
    chat_start = datetime.datetime.fromisoformat(path.stem.removesuffix('CEST'))

    with open(path) as f:
        soup = bs4.BeautifulSoup(f)

    messages = []

    cur_sent_at: datetime.datetime | None = None
    cur_sender: str | None = None
    cur_text: str  | None = None

    for c in soup.body.children:
        if c.name == 'font':
            # Get timestamp
            m = re.match(r'\((\d+):(\d+):(\d+)\)', c.font.get_text())
            time_sent = datetime.time(int(m.group(1)), int(m.group(2)), int(m.group(3)))
            cur_sent_at = datetime_sent(chat_start, time_sent)

            # Get sender
            cur_sender = c.b.get_text().strip().removesuffix(':')

        elif c.name is None:
            cur_text = c.get_text()

        elif c.name == 'a':
            cur_text = '<' + c['href'] + '>'

        elif c.name == 'br':
            messages.append(Message(cur_sent_at, cur_sender, cur_text))
            cur_sent_at = None
            cur_sender = None
            cur_text = None

        elif c.name == 'h3':
            pass # Ignore log header


        else:
            assert False, c

    return messages




def parse_messages_in_chat_folder(chat_folder_path: Path) -> list[Message]:
    messages = []
    for file_path in chat_folder_path.iterdir():
        messages.extend(parse_messages_in_chat_file(file_path))

    messages.sort()
    return messages




def main():
    path = Path()

    for message in parse_messages_in_chat_folder(path):
        print(f'({message.sent_at}) {message.sender} : {message.text}')

if __name__ == '__main__':
    main()