Gestion des commandes K-Psul donnant un négatif

* Settings
  - New: OVERDRAFT_AMOUNT
        Découvert autorisé par défaut
  - New: OVERDRAFT_DURATION
        Durée maximum d'un découvert par défaut
* K-Psul : Gestion des commandes aboutissant à un négatif
  - Si une commande aboutit à un nouveau solde négatif, demande la
      permission 'kfet.perform_negative_operations'
  - Si le total de la commande est négatif, vérifie que ni la
      contrainte de temps de découvert, ni celle de montant maximum
      n'est outrepassée. Si ce n'est pas le cas, la commande ne peut
      être enregistrée jusqu'à définir des "règles de négatif" pour le compte
      concerné.
      La durée maximum d'un découvert est celle dans AccountNegative si
      elle y est définie pour le compte concerné, sinon celle par défaut
      (Settings.OVERDRAFT_DURATION).
      Il en est de même pour le découvert maximum autorisé. Attention:
      le découvert doit être exprimé sous forme de valeur positive aussi
      bien dans AccountNegative que pour Settings.OVERDRAFT_AMOUNT.
  - Si les permissions nécessaires sont présentes, qu'il
      n'y a pas de blocage et que le compte n'a pas encore d'entrée dans
      AccountNegative, création d'une entrée avec start=now()
  - Si la balance d'un compte est positive après une commande, supprime
      l'entrée dans AccountNegative associée au compte si le "décalage
      de zéro" (donné par balance_offset) est nul. Sinon cela veut dire
      que le compte n'est pas réellement en positif.
* Modèles
    - Fix: Account.save() fonctionne dans le cas où data est vide
    - Modif: AccountNegative - Valeurs par défaut, NULL...

kfet/migrations/0020_auto_20160808_0450.py

@@ -0,0 +1,20 @@
+# -*- coding: utf-8 -*-
+from __future__ import unicode_literals
+
+from django.db import models, migrations
+import datetime
+
+
+class Migration(migrations.Migration):
+
+    dependencies = [
+        ('kfet', '0019_auto_20160808_0343'),
+    ]
+
+    operations = [
+        migrations.AlterField(
+            model_name='accountnegative',
+            name='start',
+            field=models.DateTimeField(default=datetime.datetime.now, blank=True, null=True),
+        ),
+    ]

kfet/migrations/0021_auto_20160808_0506.py

@@ -0,0 +1,19 @@
+# -*- coding: utf-8 -*-
+from __future__ import unicode_literals
+
+from django.db import models, migrations
+
+
+class Migration(migrations.Migration):
+
+    dependencies = [
+        ('kfet', '0020_auto_20160808_0450'),
+    ]
+
+    operations = [
+        migrations.AlterField(
+            model_name='accountnegative',
+            name='start',
+            field=models.DateTimeField(default=None, blank=True, null=True),
+        ),
+    ]

kfet/migrations/0022_auto_20160808_0512.py

@@ -0,0 +1,24 @@
+# -*- coding: utf-8 -*-
+from __future__ import unicode_literals
+
+from django.db import models, migrations
+
+
+class Migration(migrations.Migration):
+
+    dependencies = [
+        ('kfet', '0021_auto_20160808_0506'),
+    ]
+
+    operations = [
+        migrations.AlterField(
+            model_name='accountnegative',
+            name='authorized_overdraft',
+            field=models.DecimalField(blank=True, decimal_places=2, null=True, default=None, max_digits=6),
+        ),
+        migrations.AlterField(
+            model_name='accountnegative',
+            name='balance_offset',
+            field=models.DecimalField(blank=True, decimal_places=2, null=True, default=None, max_digits=6),
+        ),
+    ]

kfet/migrations/0023_auto_20160808_0535.py

@@ -0,0 +1,24 @@
+# -*- coding: utf-8 -*-
+from __future__ import unicode_literals
+
+from django.db import models, migrations
+
+
+class Migration(migrations.Migration):
+
+    dependencies = [
+        ('kfet', '0022_auto_20160808_0512'),
+    ]
+
+    operations = [
+        migrations.RenameField(
+            model_name='accountnegative',
+            old_name='authorized_overdraft',
+            new_name='authz_overdraft_amount',
+        ),
+        migrations.AddField(
+            model_name='accountnegative',
+            name='authz_overdraft_until',
+            field=models.DateTimeField(null=True, default=None, blank=True),
+        ),
+    ]

kfet/migrations/0024_settings_value_duration.py

@@ -0,0 +1,19 @@
+# -*- coding: utf-8 -*-
+from __future__ import unicode_literals
+
+from django.db import models, migrations
+
+
+class Migration(migrations.Migration):
+
+    dependencies = [
+        ('kfet', '0023_auto_20160808_0535'),
+    ]
+
+    operations = [
+        migrations.AddField(
+            model_name='settings',
+            name='value_duration',
+            field=models.DurationField(null=True, default=None, blank=True),
+        ),
+    ]

kfet/models.py

@@ -4,14 +4,15 @@ from django.core.exceptions import PermissionDenied, ValidationError
 from django.core.validators import RegexValidator
 from gestioncof.models import CofProfile
 from django.utils.six.moves import reduce
-import datetime
+from django.utils import timezone
+from datetime import date, timedelta
 import re
 
 def choices_length(choices):
     return reduce(lambda m, choice: max(m, len(choice[0])), choices, 0)
 
 def default_promo():
-    now = datetime.date.today()
+    now = date.today()
     return now.month <= 8 and now.year-1 or now.year
 
 class Account(models.Model):
@@ -28,7 +29,7 @@ class Account(models.Model):
         default = 0)
     is_frozen = models.BooleanField(default = False)
     # Optional
-    PROMO_CHOICES = [(r,r) for r in range(1980, datetime.date.today().year+1)]
+    PROMO_CHOICES = [(r,r) for r in range(1980, date.today().year+1)]
     promo = models.IntegerField(
         choices = PROMO_CHOICES,
         blank = True, null = True, default = default_promo())
@@ -95,12 +96,32 @@ class Account(models.Model):
 
     def perms_to_perform_operation(self, amount):
         perms = []
+        stop_ope = False
+        # Checking is frozen account
         if self.is_frozen:
             perms.append('kfet.override_frozen_protection')
         new_balance = self.balance + amount
-        if new_balance < 0:
+        if new_balance < 0 and amount < 0:
+            # Retrieving overdraft amount limit
+            if (hasattr(self, 'negative')
+                and self.negative.authz_overdraft_amount is not None):
+                overdraft_amount = - self.negative.authz_overdraft_amount
+            else:
+                overdraft_amount = - Settings.OVERDRAFT_AMOUNT()
+            # Retrieving overdraft datetime limit
+            if (hasattr(self, 'negative')
+                    and self.negative.authz_overdraft_until is not None):
+                overdraft_until = self.negative.authz_overdraft_until
+            elif hasattr(self, 'negative'):
+                overdraft_until = \
+                    self.negative.start + Settings.OVERDRAFT_DURATION()
+            else:
+                overdraft_until = timezone.now() + Settings.OVERDRAFT_DURATION()
+            # Checking it doesn't break 1 rule
+            if new_balance < overdraft_amount or timezone.now() > overdraft_until:
+                stop_ope = True
             perms.append('kfet.perform_negative_operations')
-        return perms
+        return perms, stop_ope
 
     # Surcharge Méthode save() avec gestions de User et CofProfile
     # Args:
@@ -109,7 +130,7 @@ class Account(models.Model):
     # - Enregistre User, CofProfile à partir de "data"
     # - Enregistre Account
     def save(self, data = {}, *args, **kwargs):
-        if self.pk:
+        if self.pk and data:
             # Account update
 
             # Updating User with data
@@ -122,7 +143,7 @@ class Account(models.Model):
             cof = self.cofprofile
             cof.departement = data.get("departement", cof.departement)
             cof.save()
-        else:
+        elif data:
             # New account
 
             # Checking if user has already an account
@@ -151,6 +172,7 @@ class Account(models.Model):
             if "departement" in data:
                 cof.departement = data['departement']
             cof.save()
+        if data:
             self.cofprofile = cof
         super(Account, self).save(*args, **kwargs)
 
@@ -168,13 +190,16 @@ class AccountNegative(models.Model):
     account = models.OneToOneField(
         Account, on_delete = models.PROTECT,
         related_name = "negative")
-    start = models.DateTimeField(default = datetime.datetime.now)
+    start = models.DateTimeField(
+        blank = True, null = True, default = None)
     balance_offset = models.DecimalField(
         max_digits = 6, decimal_places = 2,
-        default = 0)
-    authorized_overdraft = models.DecimalField(
+        blank = True, null = True, default = None)
+    authz_overdraft_amount = models.DecimalField(
         max_digits = 6, decimal_places = 2,
-        default = 0)
+        blank = True, null = True, default = None)
+    authz_overdraft_until = models.DateTimeField(
+        blank = True, null = True, default = None)
     comment = models.CharField(max_length = 255, blank = True)
 
 class Checkout(models.Model):
@@ -440,6 +465,8 @@ class Settings(models.Model):
     value_account = models.ForeignKey(
         Account, on_delete = models.PROTECT,
         blank = True, null = True, default = None)
+    value_duration = models.DurationField(
+        blank = True, null = True, default = None)
 
     @staticmethod
     def setting_inst(name):
@@ -465,3 +492,17 @@ class Settings(models.Model):
             return Settings.setting_inst("ADDCOST_FOR").value_account
         except Settings.DoesNotExist:
             return None;
+
+    @staticmethod
+    def OVERDRAFT_DURATION():
+        try:
+            return Settings.setting_inst("OVERDRAFT_DURATION").value_duration
+        except Settings.DoesNotExist:
+            return timedelta()
+
+    @staticmethod
+    def OVERDRAFT_AMOUNT():
+        try:
+            return Settings.setting_inst("OVERDRAFT_AMOUNT").value_decimal
+        except Settings.DoesNotExist:
+            return 0

kfet/views.py

@@ -10,8 +10,9 @@ from django.contrib.auth.models import User, Permission
 from django.http import HttpResponse, JsonResponse, Http404
 from django.forms import modelformset_factory
 from django.db import IntegrityError, transaction
+from django.utils import timezone
 from gestioncof.models import CofProfile, Clipper
-from kfet.models import Account, Checkout, Article, Settings
+from kfet.models import Account, Checkout, Article, Settings, AccountNegative
 from kfet.forms import *
 from collections import defaultdict
 
@@ -458,12 +459,12 @@ def kpsul_perform_operations(request):
             on_acc = operationgroup.on_acc
             on_acc = Account.objects.select_for_update().get(pk=on_acc.pk)
             # Adding required permissions to perform operation group
-            opegroup_perms = on_acc.perms_to_perform_operation(
+            (opegroup_perms, stop_ope) = on_acc.perms_to_perform_operation(
                 amount = operationgroup.amount)
             required_perms += opegroup_perms
 
             # Checking authenticated user has all perms
-            if not request.user.has_perms(required_perms):
+            if stop_ope or not request.user.has_perms(required_perms):
                 raise PermissionDenied
 
             # If 1 perm is required, saving who perform the operations
@@ -473,9 +474,22 @@ def kpsul_perform_operations(request):
             # Filling cof status for statistics
             operationgroup.is_cof = on_acc.is_cof
 
-            # Saving account's balance
+            # Saving account's balance and adding to Negative if not in
             on_acc.balance += operationgroup.amount
+            if on_acc.balance < 0:
+                if hasattr(on_acc, 'negative'):
+                    if not on_acc.negative.start:
+                        on_acc.negative.start = timezone.now()
+                        on_acc.negative.save()
+                else:
+                    negative = AccountNegative(
+                        account = on_acc, start = timezone.now())
+                    negative.save()
+            elif (hasattr(on_acc, 'negative')
+                    and not on_acc.negative.balance_offset):
+                on_acc.negative.delete()
             on_acc.save()
+
             # Saving addcost_for with new balance if there is one
             if is_addcost:
                 addcost_for.balance += addcost_total
@@ -494,16 +508,16 @@ def kpsul_perform_operations(request):
                     operation.article.save()
                 data['operations'].append(operation.pk)
     except PermissionDenied:
-        # Sending BAD_REQUEST with missing perms
+        # Sending BAD_REQUEST with missing perms or url to manage negative
         missing_perms = \
             [ Permission.objects.get(codename=codename).name for codename in (
                 (perm.split('.'))[1] for perm in
                 required_perms if not request.user.has_perm(perm)
             )]
+        if missing_perms:
             data['errors'].append({'missing_perms': missing_perms })
+        if stop_ope:
+            data['errors'].append({'negative': 'url to manage negative'})
         return JsonResponse(data, status=403)
-    except IntegrityError:
-        data['errors'].append('DB error')
-        return JsonResponse(data, status=500)
 
     return JsonResponse(data)