Project_Camper/vagus/reservation/models.py

from django.db import models
from django.utils.translation import gettext_lazy as _
from django.utils import timezone
from django.utils.translation import ugettext as _
from django.core.exceptions import ValidationError
from django.conf import settings
from django.core.exceptions import NON_FIELD_ERRORS
from django.db.models import Q
from django import forms
from django.contrib import messages
from django.template.defaultfilters import slugify
from django.urls import reverse


STATUS = (
    ('Confirmed',_('Rezerwacja potwierdzona')),
    ('Requsted',_('Oczekuję na potwierdzenie')),
    ('Cancelled',_('Anulowana')),
)



class Reservation(models.Model):
    id = models.AutoField(primary_key= True)
    user = models.ForeignKey(settings.AUTH_USER_MODEL, verbose_name=_("User"), on_delete=models.CASCADE)
    offer = models.ForeignKey("camper.Offer", verbose_name=_("Offer"), on_delete=models.CASCADE)
    created_date = models.DateTimeField(auto_now_add=True)
    reservation_start_date = models.DateField(default = timezone.now,)
    reservation_end_date = models.DateField()
    reservation_cost = models.DecimalField(max_digits=12,default=0,decimal_places=2)
    message_to_owner = models.TextField(max_length=500, blank = True, null = True)
    status = models.CharField(choices = STATUS, max_length  = 50)
    slug = models.SlugField(max_length=255,editable = False, default='', unique = False)

    def __str__(self):
        return "%s (%s to %s)" % (self.user.email,
                                       self.reservation_start_date.strftime(
                                        "%Y/%m/%d"),
                                        self.reservation_end_date.strftime(
                                      "%Y/%m/%d"),)
    @property                                
    def get_total_cost(self):
        diff_days = self.reservation_end_date - self.reservation_start_date
        self.reservation_cost = diff_days.days * self.offer.price
        return self.reservation_cost

    def clean(self,*args,**kwargs):
        errors = {}
        today_date =  timezone.now().date()
        if self.created_date != None:
            if self.reservation_start_date < today_date:
                errors['reservation_start_date'] = "Rezerwacja nie moze rozpoczynać sie w przeszłości"
            if self.reservation_end_date < self.reservation_start_date:
                errors['reservation_end_date'] = "Data zakończenia wynajmu nie moze byc data wczesniejsza / równa od daty rozpoczecia."
            if self.reservation_end_date == self.reservation_start_date:
                errors['reservation_end_date'] = "Wynajem nie moze kończyc sie w dniu rozpoczecia wynajmu."
            if errors:               
                raise forms.ValidationError(errors)
    
    def get_absolute_url(self):
        return reverse("reservation_detail", kwargs={"slug": self.slug})
    

    def save(self,*args,**kwargs):
        errors = {}
        filter_params = dict(reservation_end_date__lte=self.reservation_end_date, reservation_start_date__gte=self.reservation_start_date,offer =self.offer) 
        if Reservation.objects.filter(**filter_params):
            errors[NON_FIELD_ERRORS] = "Kamper w tym okresie jest juz zarezerwowany."
        if errors:       
            raise forms.ValidationError(errors)
        else:
            self.slug = slugify(f'{self.offer.title}-{self.id}-/{self.reservation_start_date}-{self.reservation_end_date}')
            return super(Reservation,self).save(*args,**kwargs)