import uuid
from datetime import datetime

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


class TimeEntry(models.Model):
    user = models.ForeignKey(
        settings.AUTH_USER_MODEL,
        on_delete=models.CASCADE,
        related_name='time_entries',
    )

    # Même group_id = même pointage logique réparti sur plusieurs jours.
    # NULL pour les pointages classiques sur une seule journée.
    group_id = models.UUIDField(
        null=True,
        blank=True,
        db_index=True,
    )

    date = models.DateField()

    start_time = models.TimeField(
        null=True,
        blank=True,
    )

    end_time = models.TimeField(
        null=True,
        blank=True,
    )

    end_time = models.TimeField(
        null=True,
        blank=True,
    )

    created_at = models.DateTimeField(
        auto_now_add=True,
    )

    updated_at = models.DateTimeField(
        auto_now=True,
    )

    class Meta:
        ordering = ['-date', '-start_time']

        unique_together = [
            'user',
            'date',
            'start_time',
        ]

    def __str__(self):
        return (
            f"{self.user.username} - "
            f"{self.date} "
            f"({self.start_time} to {self.end_time})"
        )

    @property
    def duration(self):
        if not self.start_time or not self.end_time:
            return None

        end_date = self.end_date or self.date

        start = datetime.combine(
            self.date,
            self.start_time,
        )

        end = datetime.combine(
            end_date,
            self.end_time,
        )

        seconds = (
            end - start
        ).total_seconds()

        if seconds < 0:
            return None

        return seconds / 3600

    @property
    def day_of_week(self):
        return self.date.strftime('%A')

    @property
    def is_complete(self):
        return bool(
            self.start_time
            and self.end_time
        )

    @property
    def is_incomplete(self):
        return not self.is_complete