from math import ceil
from datetime import date, datetime, timedelta

from django.db import models
from django.db.models import F, Q

calendrier = {
    "C" : [
        ( date(2023, 10, 21), date(2023, 11, 6) ),
        ( date(2023, 12, 23), date(2024, 1, 8) ),
        ( date(2024, 2, 10), date(2024, 2, 26) ),
        ( date(2024, 4, 6), date(2024, 4, 22) ),
    ]
}

class Lycee(models.Model):
    uai = models.CharField(max_length=10)
    libelle = models.CharField(max_length=100)
    vacances = models.CharField(max_length=1)

class Classe(models.Model):
    lycee = models.ForeignKey(Lycee, on_delete=models.CASCADE)
    libelle = models.CharField(max_length=20)
    annee = models.IntegerField()
    jour_zero = models.DateField()

class Periode(models.Model):
    classe = models.ForeignKey(Classe, on_delete=models.CASCADE)
    #critere_colle = models.ForeignKey(Critere, on_delete=models.SET_NULL, null=True)
    libelle = models.CharField(max_length=100)
    debut = models.DateField()
    fin = models.DateField()

    class Meta:
        ordering = ["debut"]


    def no_semaine(self, jour):
        zone = self.classe.lycee.vacances
        vacances = calendrier[zone]
        jour0 = self.classe.jour_zero

        n = 1 + ((jour - jour0).days)//7
        for debut, fin in vacances:
            if jour > debut:
                n -= 2
        return n

    def range_semaines(self):
        return range(self.no_semaine(self.debut), self.no_semaine(self.fin)+1)

    def date_debut_sem(self, n):
        zone = self.classe.lycee.vacances
        vacances = calendrier[zone]
        jour0 = self.classe.jour_zero

        jour = jour0 + (n-1) * timedelta(weeks=1)
        
        for debut, _ in vacances:
            if jour >= debut:
                jour += 2*timedelta(weeks=1)

        return jour


class Matiere(models.Model):
    classe = models.ForeignKey(Classe, on_delete=models.CASCADE)
    libelle = models.CharField(max_length=100)
    code = models.CharField(max_length=20)

class Critere(models.Model):
    periode = models.ForeignKey(Periode, on_delete=models.CASCADE)
    libelle = models.CharField(max_length=100)

class Groupe(models.Model):
    #class Meta:
    #    ordering=[F("periode").classe.libelle, F("periode").libelle, "libelle"]
    
    periode = models.ForeignKey(Periode, on_delete=models.CASCADE)
    critere = models.ForeignKey(Critere, null=True, on_delete=models.CASCADE)
    libelle = models.CharField(max_length=100)

    def membres(self):
        return Etudiant.objects.filter(id__in=Appartenance.objects.filter(groupe=self))

class Etudiant(models.Model):
    class Meta:
        ordering=["classe", "nom", "prenom"]

    classe = models.ForeignKey(Classe, on_delete=models.CASCADE)
    prenom = models.CharField(max_length=100)
    nom = models.CharField(max_length=100)
    #lv1 = models.ForeignKey(Matiere, on_delete=models.CASCADE)
    #lv2 = models.ForeignKey(Matiere, on_delete=models.CASCADE)

    def appartient(self, groupe, periode):
        return Appartenance.objects.filter(etudiant=self, groupe=groupe).exists()

    def groupe_du_critere(self, periode, critere):
        if isinstance(critere, str):
            critere = Critere.objects.get(periode=periode, libelle=critere)

        return Appartenance.objects.get(groupe__periode=periode, etudiant=self, groupe__critere=critere).groupe

    def groupe_de_colle(self, periode):
        return self.groupe_du_critere(periode, "colle")

class Appartenance(models.Model):
    etudiant = models.ForeignKey(Etudiant, on_delete=models.CASCADE)
    groupe = models.ForeignKey(Groupe, on_delete=models.CASCADE)

class Colleur(models.Model):
    civilite = models.CharField(max_length=1)
    nom = models.CharField(max_length=100)

class Creneau(models.Model):
    periode = models.ForeignKey(Periode, on_delete=models.CASCADE)
    jour = models.IntegerField()
    heure = models.TimeField()
    duree = models.DurationField()
    salle = models.CharField(max_length=20)
    matiere = models.ForeignKey(Matiere, on_delete=models.CASCADE)
    colleur = models.ForeignKey(Colleur, on_delete=models.CASCADE)
    est_colle = models.BooleanField()
    capacite = models.IntegerField()

class Rotation(models.Model):
    creneau = models.ForeignKey(Creneau, on_delete=models.CASCADE)
    groupes = models.ManyToManyField(Groupe)
    semaine = models.IntegerField()

    def effectif(self):
        n_base = sum(len(groupe.membres()) for groupe in self.groupes.all())
        n_plus = len(Amendement.objects.filter(est_positif=True, rotation=self))
        n_moins = len(Amendement.objects.filter(est_positif=False, rotation=self))

        return n_base + n_plus - n_moins

    def est_pleine(self):
        eff = self.effectif()

        if eff>self.creneau.capacite:
            raise models.IntegrityError
        else:
            return eff==self.creneau.capacite

class Amendement(models.Model):
    est_positif = models.BooleanField()
    rotation = models.ForeignKey(Rotation, on_delete=models.CASCADE)
    etudiant = models.ForeignKey(Etudiant, on_delete=models.CASCADE)


class Utilisateur(models.Model):
    username = models.CharField(max_length=100)
    password = models.CharField(max_length=300)
    timestamp = models.DateTimeField(auto_now_add=True)
    etudiant = models.ForeignKey(Etudiant, on_delete=models.SET_NULL, null=True)
    colleur = models.ForeignKey(Colleur, on_delete=models.SET_NULL, null=True)