#!/bin/env python

import argparse
import requests
from bs4 import BeautifulSoup
from datetime import datetime, timedelta, time
import icalendar as ical
from zoneinfo import ZoneInfo

URL = 'https://www.physi.uni-heidelberg.de/Einrichtungen/FP/seminar/seminar.php'
SEMINAR_LENGTH = 45 #min


def getcal():
    page = requests.get(URL)
    soup = BeautifulSoup(page.content, 'lxml')
    cal = ical.Calendar()

    for table in soup.find(id='content').find_all('table')[1:]:
        try:
            trs = table.find_all('tr')
            tutor = trs[0].find_all('th')[1].text.strip()
            zeit, ort = trs[0].find('td').text.split(',', 1)
            zeit, ort = zeit.strip(), ort.strip()
            zeit = time(*map(int, zeit.split(' ')[-1].split(':')))
        except Exception as e:
            print(e)
            continue

        for tr in trs[1:]:
            try:
                tds = tr.find_all('td')
                if len(tds) < 2:
                    continue

                event = ical.Event()
                datum = datetime.strptime(tds[0].text.strip(), '%d.%m.%y').date()
                start = datetime.combine(datum, zeit, tzinfo=ZoneInfo('Europe/Berlin'))
                event.add('dtstart', start)
                end = start+timedelta(minutes=SEMINAR_LENGTH)
                event.add('dtend', end)

                summary = tds[1].text.strip()
                if summary in ['', 'noch frei', 'kein Vortrag']:
                    continue
                if len(tds) > 2:
                    name = tds[2].text.strip()
                    if 'kein Seminar' in name:
                        continue
                    summary += ': '+name
                summary += ' ({})'.format(tutor)
                event.add('summary', summary)

                if len(tds) > 3:
                    description = 'Betreuer/in: {}'.format(tds[3].text.strip())
                    event.add('description', description)

                event.add('location', ort)

                cal.add_component(event)
            except Exception as e:
                print(e)
                continue

    return cal


if __name__ == "__main__":
    parser = argparse.ArgumentParser()
    parser.add_argument('-o', '--out', type=str, default='fp-seminare.ics', help='Output path')
    args = parser.parse_args()

    cal = getcal()

    with open(args.out, 'wb') as f:
        f.write(cal.to_ical())