work-helpers/work_helpers/ics2table.py

from datetime import datetime, timedelta
from typing import Iterable

import click
import pyperclip
import requests

# typing
RawEvent = dict[str:tuple[str|datetime,str]]
Event = dict[str:str]
TableMetaData = dict[str:int]

ICAL_URL = "https://bwsyncandshare.kit.edu/remote.php/dav/public-calendars/69o9HEM9aeZnER8S/?export"

ICS_DATE_FORMAT = "%Y%m%dT%H%M%S"
GERMAN_DATE_FORMAT = "%d.%m.%Y %H:%M"

EARLIEST = datetime.now() - timedelta(days=30 * 3)
LATEST =   datetime.now() + timedelta(days=30 * 6)

TABLE_COLUMN_ORDER = ("date", "location", "presenter")

# for mail sending

MAIL_RECIPIENTS = ",".join([
    "cpistaff@imtek.de",
    "andrea.paola.layedra.almeida@uniklinik-freiburg.de",
    "jaro.homburger@biologie.uni-freiburg.de",
    "kubilay.acar@continental.com", 
    "Mario.diehlmann@basf.com",
    "paul.fernandez@fmf.uni-freiburg.de",
    "sunil.shetty@uniklinik-freiburg.de",
    "sofia.genoves94@gmail.com", "sofia.genoves@yahoo.com.ar"
])
MAIL_SUBJECT = "Updated Group Meeting Schedule"
MAIL_START = """
Dear All,

There is an updated group-seminar schedule available: 
"""
MAIL_END = """
If (and only if) you can't make it in person, you can join the presentations via zoom: https://uni-freiburg.zoom-x.de/j/62063730956?pwd=6poraREYWvuHkStuYDRvYhO4vhmTbt.1

Meeting-ID: 620 6373 0956
Code: Lm5xaDXPH 

You can have a look in our group meeting calendar at: https://bwsyncandshare.kit.edu/apps/calendar/p/69o9HEM9aeZnER8S

Or on our wiki: https://wiki.cpi.imtek.uni-freiburg.de/SeminarSchedule

If you want to add the schedule to your calendar app of choice, please use this subscribe link: https://bwsyncandshare.kit.edu/remote.php/dav/public-calendars/69o9HEM9aeZnER8S/?export

Best,
Holgi
"""

# parsers

def _parse_text(ics_text:str) -> str:
    text = ics_text.strip()
    return text.replace("\\,", ",")

def _parse_presenter(ics_text:str) -> str:
    text = _parse_text(ics_text)
    first, sep, last = text.partition(":")
    return first if not sep else last.strip()

def _parse_datetime(ics_text:str) -> str:
    return  datetime.strptime(ics_text.strip(), ICS_DATE_FORMAT)

def _format_datetime(date: datetime) -> str:
    return datetime.strftime(date, GERMAN_DATE_FORMAT)


class Transformer():
    def __init__(self, name, parser, formater):
        self.name = name
        self.parser = parser
        self.formater = formater


vevent_transformer = {
    "DTSTART":  Transformer("date",      parser=_parse_datetime,  formater=_format_datetime),
    "LOCATION": Transformer("location",  parser=_parse_text,      formater=str),
    "SUMMARY":  Transformer("presenter", parser=_parse_presenter, formater=str),
}


def get_ics(url:str) -> str:
    try:
        response = requests.get(url)
    except IndexError: 
        msg = f"Could not load calender from url"
        raise IOError(msg)
    return response.text


def extract_event_info(response:str) -> Iterable[Event]:
    events = (
        event for event in 
        _extract_event_info(response)
        if EARLIEST < event["date"][0] < LATEST
    )
    for event in sorted(events, key=lambda d: d["date"]):
        yield {key: values[1] for key, values in event.items()}

def _extract_event_info(response:str) -> Iterable[RawEvent]:
    handle = (line for line in response.splitlines())
    for line in handle:
        if line.upper().startswith("BEGIN:VEVENT"):
            yield extract_vevent(handle)

def extract_vevent(handle:Iterable[str]) -> RawEvent:
    event = {}
    for line in handle:
        if line.upper().startswith("END:VEVENT"):
            break
        raw_key, _, raw_value = line.partition(":")
        key, _, _ = raw_key.partition(";")
        if t := vevent_transformer.get(key):
            value = t.parser(raw_value)
            text = t.formater(value)
            event[t.name] = (value, text)
    return event


def create_wiki_table(events:Iterable[Event]) -> str:
    table_meta_data = _get_table_meta_data(events)
    headers = {key: f"'''{key.capitalize()}'''" for key in TABLE_COLUMN_ORDER}
    lines = [
        _create_table_line(headers, table_meta_data),
    ]
    for event in events:
        lines.append(_create_table_line(event, table_meta_data))
    return "\n".join(lines)


def _create_table_line(event:Event, meta:TableMetaData) -> str:
    columns = [event[key].ljust(meta[key]) for key in TABLE_COLUMN_ORDER]
    inner = " || ".join(columns)
    return f"|| {inner} ||"


def _get_table_meta_data(events:Iterable[Event]) -> TableMetaData:
    meta = {}
    for event in events:
        for key, value in event.items():
            meta[key] = max(meta.get(key, 0), len(value))
    return meta


def create_email_table(events:Iterable[Event]) -> str:
    table_meta_data = _get_table_meta_data(events)
    date_key, _, name_key = TABLE_COLUMN_ORDER
    pad_date = table_meta_data[date_key]
    lines = [
        (event[date_key].ljust(pad_date) + " | " + event[name_key]) for event in events
    ]
    return "\n".join(lines)


@click.command()
def group_schedule():
    ics_file = get_ics(ICAL_URL)
    events = list(extract_event_info(ics_file))

    wiki_table = create_wiki_table(events)
    email_table = create_email_table(events)
    
    components = [
        wiki_table,
        "",
        "",
        "",
        MAIL_RECIPIENTS,
        "",
        MAIL_SUBJECT,
        MAIL_START,
        email_table,
        MAIL_END
    ]
    
    text = "\n".join(components)
    print(text)
    pyperclip.copy(text)