import time
import datetime
import re
import logging
from .data import Message, channel_mapping
from . import gui

log = logging.getLogger(__name__)
logging.basicConfig(level=logging.DEBUG)


re_log = re.compile(
    r'(?P<date>\d\d\d\d/\d\d/\d\d \d\d:\d\d:\d\d) (\d+) (\S+) \[(?P<level>\S+) (\S+) (\d+)\] '
    r'(?P<channel>[#@%$&]?)(?P<ToFrom>To|From)?\s?(?P<guild><\S+>)? ?(?P<user>[^:]+): (?P<message>.*)'
)


def parse_log(text: str) -> Message:
    result = re_log.search(text)
    if not result:
        log.debug(f'Result is none for text "{text}"')
        return None
    date = datetime.datetime.strptime(
        result.group('date'), '%Y/%m/%d %H:%M:%S')
    guild = result.group('guild')
    if guild:
        guild = guild.strip('<>')
    return Message(result.group('message'),
                   date,
                   result.group('user'),
                   channel_mapping[result.group('channel')],
                   guild,
                   result.group('ToFrom'))


def read_log(logfile: str, app: gui.Gui) -> None:
    logfile = open(logfile, 'r', encoding='utf8')
    loglines = follow(logfile)
    for line in loglines:
        message = parse_log(line)
        log.debug(message)
        if message and message.trade and message.to_from == 'From':
            app.add_tab(30, message)


def follow(thefile: str):
    thefile.seek(0, 2)
    while True:
        line = thefile.readline()
        if not line:
            time.sleep(0.1)
            continue
        yield line