from django.conf import settings
from django.db import models


class PlanningState(models.Model):
    user = models.OneToOneField(settings.AUTH_USER_MODEL, on_delete=models.CASCADE)
    revision = models.PositiveIntegerField(default=0)


class WorkSchedule(models.Model):
    class Mode(models.TextChoices):
        PRECISE = 'precise', 'Horaires précis'
        DAILY_HOURS = 'daily_hours', 'Nombre d’heures par jour'
        WEEKLY_HOURS = 'weekly_hours', 'Nombre d’heures par semaine'

    user = models.ForeignKey(settings.AUTH_USER_MODEL, on_delete=models.CASCADE, related_name='work_schedules')
    valid_from = models.DateField()
    cycle_weeks = models.PositiveSmallIntegerField(default=1)
    mode = models.CharField(max_length=16, choices=Mode.choices, default=Mode.PRECISE)
    day_targets = models.JSONField(default=list, blank=True)
    week_targets = models.JSONField(default=list, blank=True)
    valid_to = models.DateField(null=True, blank=True)
    created_by = models.ForeignKey(settings.AUTH_USER_MODEL, null=True, on_delete=models.SET_NULL, related_name='+')
    updated_at = models.DateTimeField(auto_now=True)

    class Meta:
        ordering = ['-valid_from', '-pk']
        constraints = [models.UniqueConstraint(fields=['user', 'valid_from'], name='schedule_user_start_unique')]


class WorkScheduleSlot(models.Model):
    schedule = models.ForeignKey(WorkSchedule, on_delete=models.CASCADE, related_name='slots')
    weekday = models.PositiveSmallIntegerField()  # lundi = 0
    week_index = models.PositiveSmallIntegerField(default=0)
    start_time = models.TimeField()
    end_time = models.TimeField()
    end_day_offset = models.PositiveSmallIntegerField(default=0)

    class Meta:
        ordering = ['week_index', 'weekday', 'start_time']


class ScheduleException(models.Model):
    class Mode(models.TextChoices):
        PRECISE = 'precise', 'Horaires précis'
        DAILY_HOURS = 'daily_hours', 'Nombre d’heures à effectuer'

    class Kind(models.TextChoices):
        WORK = 'work', 'Horaires exceptionnels'
        REST = 'rest', 'Repos'
        ABSENCE = 'absence', 'Congé / absence'

    user = models.ForeignKey(settings.AUTH_USER_MODEL, on_delete=models.CASCADE, related_name='schedule_exceptions')
    label = models.CharField(max_length=160, blank=True)
    kind = models.CharField(max_length=8, choices=Kind.choices, default=Kind.WORK)
    mode = models.CharField(max_length=16, choices=Mode.choices, default=Mode.PRECISE)
    target_minutes = models.PositiveSmallIntegerField(null=True, blank=True)
    start_date = models.DateField()
    end_date = models.DateField(null=True, blank=True)
    recurring = models.BooleanField(default=False)
    weekdays = models.JSONField(default=list)
    every_weeks = models.PositiveSmallIntegerField(default=1)
    created_by = models.ForeignKey(settings.AUTH_USER_MODEL, null=True, on_delete=models.SET_NULL, related_name='+')
    request = models.ForeignKey('DayChangeRequest', null=True, blank=True, on_delete=models.SET_NULL, related_name='applied_exceptions')
    created_at = models.DateTimeField(auto_now_add=True)
    updated_at = models.DateTimeField(auto_now=True)

    class Meta:
        ordering = ['-pk']
        indexes = [models.Index(fields=['user', 'start_date'], name='exception_user_date_idx')]


class ExceptionSlot(models.Model):
    exception = models.ForeignKey(ScheduleException, on_delete=models.CASCADE, related_name='slots')
    start_time = models.TimeField()
    end_time = models.TimeField()
    end_day_offset = models.PositiveSmallIntegerField(default=0)

    class Meta:
        ordering = ['start_time']


class DayChangeRequest(models.Model):
    class Kind(models.TextChoices):
        LEAVE = 'leave', 'Congé / absence'
        HOURS = 'hours', 'Modification d’horaires'
        MOVE = 'move', 'Déplacement de journée'
        SWAP = 'swap', 'Échange de journée'

    class Status(models.TextChoices):
        PENDING = 'pending', 'En attente'
        APPROVED = 'approved', 'Acceptée'
        REJECTED = 'rejected', 'Refusée'
        CANCELLED = 'cancelled', 'Annulée'

    user = models.ForeignKey(settings.AUTH_USER_MODEL, on_delete=models.CASCADE, related_name='day_requests')
    kind = models.CharField(max_length=8, choices=Kind.choices)
    start_date = models.DateField()
    end_date = models.DateField()
    target_date = models.DateField(null=True, blank=True)
    target_user = models.ForeignKey(settings.AUTH_USER_MODEL, null=True, blank=True, on_delete=models.SET_NULL, related_name='received_swaps')
    reason = models.TextField(blank=True, max_length=2000)
    proposed_slots = models.JSONField(default=list)
    before = models.JSONField(default=list)
    after = models.JSONField(default=list)
    status = models.CharField(max_length=10, choices=Status.choices, default=Status.PENDING)
    reviewed_by = models.ForeignKey(settings.AUTH_USER_MODEL, null=True, blank=True, on_delete=models.SET_NULL, related_name='+')
    reviewed_at = models.DateTimeField(null=True, blank=True)
    response = models.TextField(blank=True, max_length=2000)
    created_at = models.DateTimeField(auto_now_add=True)
    updated_at = models.DateTimeField(auto_now=True)

    class Meta:
        ordering = ['-created_at', '-pk']
        indexes = [models.Index(fields=['status', 'user'], name='request_status_user_idx')]