friendsmap/map/models.py

from django.contrib.auth.models import AbstractUser
from django.db import models

from map.fields import CoordinateField


class BaseModel(models.Model):
    class Meta:
        abstract = True

    created_at = models.DateTimeField(auto_now_add=True)
    updated_at = models.DateTimeField(auto_now=True)


class Friend(AbstractUser):
    shares_location_to = models.ManyToManyField('Friend', related_name='is_shared_location_by', blank=True)

    def get_display_name(self):
        display_name = super().get_full_name()
        if not display_name:
            display_name = self.username

        return display_name

    def __str__(self):
        return self.get_display_name()


class FriendLocation(BaseModel):
    latitude = CoordinateField()
    longitude = CoordinateField()
    start_date = models.DateField('from', blank=True, null=True, help_text='Format : YYYY-MM-DD, example : 2018-05-31')
    end_date = models.DateField('until', blank=True, null=True, help_text='Format : YYYY-MM-DD, example : 2018-05-31')
    friend = models.OneToOneField(Friend, on_delete=models.CASCADE, related_name='location')

    @property
    def latitude_str(self):
        return str(self.latitude)

    @property
    def longitude_str(self):
        return str(self.longitude)

    def __str__(self):
        result = f'{self.friend.get_display_name()}'
        if self.start_date:
            result += f' from {self.start_date}'
        if self.end_date:
            result += f' until {self.end_date}'
        return result

    @property
    def safe_html(self):
        html = f'<strong>{self.friend.get_display_name()}</strong>'
        if self.start_date:
            html += f' from {self.start_date}'
        if self.end_date:
            html += f' until {self.end_date}'
        return html