from datetime import date, time, datetime, timedelta
from pytz import timezone

from icalendar import Calendar, Event, vCalAddress, vText

from colloscope.models import *

def emailize(nom, prenom=None):
    if prenom is not None:
        return "{}.{}@example.com" \
                .format(
                        prenom.replace(" ", "_").lower(),
                        nom.replace(" ", "_").lower()
                        )
    else:
        return "{}@example.com" \
                .format(nom.replace(" ", "_").lower())

def to_calendar(etudiant, periode):
    cal = Calendar()

    cal.add("prodid", "-//Colloscope//colles.mp2i-vms.fr//")
    cal.add("version", "2.0")

    rotations = Rotation.objects \
            .filter(groupes__membres=etudiant) \
            .select_related("creneau__periode__classe__lycee") \
            .select_related("creneau__matiere") \
            .select_related("creneau__colleur") \

    for rotation in rotations:
        event = Event()
        event.add("name", "Colle")
        event.add("summary", str(rotation))
        
        start = rotation.datetime()
        fin = start + rotation.creneau.duree

        event.add("dtstart", start)
        event.add("dtend", fin)
        event.add("dtstamp", datetime.now())

        event.add("location", f"{rotation.creneau.salle} ({rotation.creneau.periode.classe.lycee})")
        event.add("matiere", str(rotation.creneau.matiere))

        organizer = vCalAddress(f"mailto:{emailize(rotation.creneau.colleur.nom)}")
        organizer.params["cn"] = vText(str(rotation.creneau.colleur))
        organizer.params["role"] = vText("Colleur")
        event.add("organizer", organizer)

        for e in rotation.groupe_effectif():
            attendee = vCalAddress("mailto:{emailize(e.nom, prenom=e.prenom)}")
            attendee.params["cn"] = vText(str(e))
            attendee.params["role"] = vText("Etudiant")

            event.add("attendee", attendee, encode=0)

        cal.add_component(event)

    return cal