Merge pull request #128 from SchrodingersGat/price-breaks

Price breaks

InvenTree/company/templates/company/index.html

@@ -6,7 +6,7 @@
 
 <h3>Companies</h3>
 <div id='button-toolbar'>
-<h3><button style='float: right;' class="btn btn-success" id='new-company'>New Company</button></h3>
+<button style='float: right;' class="btn btn-success" id='new-company'>New Company</button>
 </div>
 
 <table class='table table-striped' id='company-table' data-toolbar='#button-toolbar'>

InvenTree/company/templates/company/partdetail.html

@@ -44,10 +44,43 @@
     <tr><td>Manufacturer</td><td>{{ part.manufacturer }}</td></tr>
     <tr><td>MPN</td><td>{{ part.MPN }}</td></tr>
 {% endif %}
+{% if part.note %}
+    <tr><td>Note</td><td>{{ part.note }}</td></tr>
+{% endif %}
+    <tr><th colspan='2'>Pricing</th></tr>
+    <tr><td>Single Price</td><td>{{ part.single_price }}</td></tr>
+{% if part.multiple > 1 %}
+    <tr><td>Order Multiple</td><td>{{ part.multiple }}</td></tr>
+{% endif %}
+{% if part.base_cost > 0 %}
+    <tr><td>Base Price (Flat Fee)</td><td>{{ part.base_cost }}</td></tr>
+{% endif %}
+{% if part.minimum > 1 %}
+    <tr><td>Minimum Order Quantity</td><td>{{ part.minimum }}</td></tr>
+{% endif %}
 </table>
 
 <br>
 
+<h3>Price Breaks</h3>
+
+<table class="table table-striped table-condensed">
+    <tr>
+        <th>Quantity</th>
+        <th>Price</th>
+    </tr>
+{% for pb in part.price_breaks.all %}
+    <tr>
+        <td>{{ pb.quantity }}</td>
+        <td>{{ pb.cost }}</td>
+    </tr>
+{% endfor %}
+</table>
+
+<div>
+    <button class='btn btn-primary' type='button'>New Price Break</button>
+</div>
+
 {% include 'modals.html' %}
 
 {% endblock %}

InvenTree/part/api.py

@@ -10,10 +10,10 @@ from django.conf.urls import url, include
 from django.shortcuts import get_object_or_404
 
 from .models import Part, PartCategory, BomItem
-from .models import SupplierPart
+from .models import SupplierPart, SupplierPriceBreak
 
 from .serializers import PartSerializer, BomItemSerializer
-from .serializers import SupplierPartSerializer
+from .serializers import SupplierPartSerializer, SupplierPriceBreakSerializer
 from .serializers import CategorySerializer
 
 from InvenTree.views import TreeSerializer
@@ -168,6 +168,24 @@ class SupplierPartList(generics.ListAPIView):
     ]
 
 
+class SupplierPriceBreakList(generics.ListCreateAPIView):
+
+    queryset = SupplierPriceBreak.objects.all()
+    serializer_class = SupplierPriceBreakSerializer
+
+    permission_classes = [
+        permissions.IsAuthenticatedOrReadOnly,
+    ]
+
+    filter_backends = [
+        DjangoFilterBackend,
+    ]
+
+    filter_fields = [
+        'part',
+    ]
+
+
 cat_api_urls = [
     url(r'^$', CategoryList.as_view(), name='api-part-category-list'),
 ]
@@ -177,6 +195,7 @@ part_api_urls = [
 
     url(r'^category/', include(cat_api_urls)),
 
+    url(r'^price-break/?', SupplierPriceBreakList.as_view(), name='api-part-supplier-price'),
     url(r'^supplier/?', SupplierPartList.as_view(), name='api-part-supplier-list'),
     url(r'^bom/?', BomList.as_view(), name='api-bom-list'),
 

InvenTree/part/forms.py

@@ -99,4 +99,11 @@ class EditSupplierPartForm(HelperForm):
                 'URL',
                 'manufacturer',
                 'MPN',
+                'note',
+                'single_price',
+                'base_cost',
+                'multiple',
+                'minimum',
+                'packaging',
+                'lead_time'
             ]

InvenTree/part/migrations/0006_auto_20190416_2354.py

@@ -0,0 +1,30 @@
+# Generated by Django 2.2 on 2019-04-16 13:54
+
+import django.core.validators
+from django.db import migrations, models
+import django.db.models.deletion
+
+
+class Migration(migrations.Migration):
+
+    dependencies = [
+        ('part', '0005_part_consumable'),
+    ]
+
+    operations = [
+        migrations.AlterField(
+            model_name='bomitem',
+            name='sub_part',
+            field=models.ForeignKey(limit_choices_to={'consumable': True}, on_delete=django.db.models.deletion.CASCADE, related_name='used_in', to='part.Part'),
+        ),
+        migrations.AlterField(
+            model_name='part',
+            name='consumable',
+            field=models.BooleanField(default=True, help_text='Can this part be used to build other parts?'),
+        ),
+        migrations.AlterField(
+            model_name='supplierpricebreak',
+            name='quantity',
+            field=models.PositiveIntegerField(validators=[django.core.validators.MinValueValidator(2)]),
+        ),
+    ]

InvenTree/part/migrations/0007_auto_20190417_0007.py

@@ -0,0 +1,54 @@
+# Generated by Django 2.2 on 2019-04-16 14:07
+
+import django.core.validators
+from django.db import migrations, models
+
+
+class Migration(migrations.Migration):
+
+    dependencies = [
+        ('part', '0006_auto_20190416_2354'),
+    ]
+
+    operations = [
+        migrations.AddField(
+            model_name='supplierpart',
+            name='note',
+            field=models.CharField(blank=True, help_text='Notes', max_length=100),
+        ),
+        migrations.AlterField(
+            model_name='supplierpart',
+            name='base_cost',
+            field=models.DecimalField(decimal_places=3, default=0, help_text='Minimum charge (e.g. stocking fee)', max_digits=10, validators=[django.core.validators.MinValueValidator(0)]),
+        ),
+        migrations.AlterField(
+            model_name='supplierpart',
+            name='description',
+            field=models.CharField(blank=True, help_text='Supplier part description', max_length=250),
+        ),
+        migrations.AlterField(
+            model_name='supplierpart',
+            name='minimum',
+            field=models.PositiveIntegerField(default=1, help_text='Minimum order quantity (MOQ)', validators=[django.core.validators.MinValueValidator(0)]),
+        ),
+        migrations.AlterField(
+            model_name='supplierpart',
+            name='multiple',
+            field=models.PositiveIntegerField(default=1, help_text='Order multiple', validators=[django.core.validators.MinValueValidator(0)]),
+        ),
+        migrations.AlterField(
+            model_name='supplierpart',
+            name='packaging',
+            field=models.CharField(blank=True, help_text='Part packaging', max_length=50),
+        ),
+        migrations.AlterField(
+            model_name='supplierpart',
+            name='single_price',
+            field=models.DecimalField(decimal_places=3, default=0, help_text='Price for single quantity', max_digits=10, validators=[django.core.validators.MinValueValidator(0)]),
+        ),
+        migrations.AlterField(
+            model_name='supplierpricebreak',
+            name='cost',
+            field=models.DecimalField(decimal_places=3, max_digits=10, validators=[django.core.validators.MinValueValidator(0)]),
+        ),
+    ]

InvenTree/part/migrations/0008_auto_20190417_0013.py

@@ -0,0 +1,19 @@
+# Generated by Django 2.2 on 2019-04-16 14:13
+
+from django.db import migrations, models
+import django.db.models.deletion
+
+
+class Migration(migrations.Migration):
+
+    dependencies = [
+        ('part', '0007_auto_20190417_0007'),
+    ]
+
+    operations = [
+        migrations.AlterField(
+            model_name='supplierpart',
+            name='part',
+            field=models.ForeignKey(limit_choices_to={'purchasable': True}, on_delete=django.db.models.deletion.CASCADE, related_name='supplier_parts', to='part.Part'),
+        ),
+    ]

InvenTree/part/migrations/0009_auto_20190417_0019.py

@@ -0,0 +1,19 @@
+# Generated by Django 2.2 on 2019-04-16 14:19
+
+from django.db import migrations, models
+import django.db.models.deletion
+
+
+class Migration(migrations.Migration):
+
+    dependencies = [
+        ('part', '0008_auto_20190417_0013'),
+    ]
+
+    operations = [
+        migrations.AlterField(
+            model_name='supplierpart',
+            name='part',
+            field=models.ForeignKey(limit_choices_to={'purchaseable': True}, on_delete=django.db.models.deletion.CASCADE, related_name='supplier_parts', to='part.Part'),
+        ),
+    ]

InvenTree/part/migrations/0010_auto_20190417_0045.py

@@ -0,0 +1,24 @@
+# Generated by Django 2.2 on 2019-04-16 14:45
+
+import django.core.validators
+from django.db import migrations, models
+
+
+class Migration(migrations.Migration):
+
+    dependencies = [
+        ('part', '0009_auto_20190417_0019'),
+    ]
+
+    operations = [
+        migrations.AlterField(
+            model_name='supplierpart',
+            name='minimum',
+            field=models.PositiveIntegerField(default=1, help_text='Minimum order quantity (MOQ)', validators=[django.core.validators.MinValueValidator(1)]),
+        ),
+        migrations.AlterField(
+            model_name='supplierpart',
+            name='multiple',
+            field=models.PositiveIntegerField(default=1, help_text='Order multiple', validators=[django.core.validators.MinValueValidator(1)]),
+        ),
+    ]

InvenTree/part/models.py

@@ -3,6 +3,8 @@ from __future__ import unicode_literals
 
 import os
 
+import math
+
 from django.utils.translation import gettext_lazy as _
 from django.core.exceptions import ValidationError
 
@@ -456,7 +458,9 @@ class SupplierPart(models.Model):
     # Link to an actual part
 # The part will have a field 'supplier_parts' which links to the supplier part options
     part = models.ForeignKey(Part, on_delete=models.CASCADE,
-                             related_name='supplier_parts')
+                             related_name='supplier_parts',
+                             limit_choices_to={'purchaseable': True},
+                             )
 
     supplier = models.ForeignKey(Company, on_delete=models.CASCADE,
                                  related_name='parts')
@@ -469,22 +473,25 @@ class SupplierPart(models.Model):
 
     URL = models.URLField(blank=True)
 
-    description = models.CharField(max_length=250, blank=True)
+    description = models.CharField(max_length=250, blank=True, help_text='Supplier part description')
+
+    # Note attached to this BOM line item
+    note = models.CharField(max_length=100, blank=True, help_text='Notes')
 
     # Default price for a single unit
-    single_price = models.DecimalField(max_digits=10, decimal_places=3, default=0)
+    single_price = models.DecimalField(max_digits=10, decimal_places=3, default=0, validators=[MinValueValidator(0)], help_text='Price for single quantity')
 
     # Base charge added to order independent of quantity e.g. "Reeling Fee"
-    base_cost = models.DecimalField(max_digits=10, decimal_places=3, default=0)
+    base_cost = models.DecimalField(max_digits=10, decimal_places=3, default=0, validators=[MinValueValidator(0)], help_text='Minimum charge (e.g. stocking fee)')
 
     # packaging that the part is supplied in, e.g. "Reel"
-    packaging = models.CharField(max_length=50, blank=True)
+    packaging = models.CharField(max_length=50, blank=True, help_text='Part packaging')
 
     # multiple that the part is provided in
-    multiple = models.PositiveIntegerField(default=1, validators=[MinValueValidator(0)])
+    multiple = models.PositiveIntegerField(default=1, validators=[MinValueValidator(1)], help_text='Order multiple')
 
     # Mimumum number required to order
-    minimum = models.PositiveIntegerField(default=1, validators=[MinValueValidator(0)])
+    minimum = models.PositiveIntegerField(default=1, validators=[MinValueValidator(1)], help_text='Minimum order quantity (MOQ)')
 
     # lead time for parts that cannot be delivered immediately
     lead_time = models.DurationField(blank=True, null=True)
@@ -501,6 +508,50 @@ class SupplierPart(models.Model):
 
         return ' | '.join(items)
 
+    @property
+    def has_price_breaks(self):
+        return self.price_breaks.count() > 0
+
+    def get_price(self, quantity, moq=True, multiples=True):
+        """ Calculate the supplier price based on quantity price breaks.
+        - If no price breaks available, use the single_price field
+        - Don't forget to add in flat-fee cost (base_cost field)
+        - If MOQ (minimum order quantity) is required, bump quantity
+        - If order multiples are to be observed, then we need to calculate based on that, too
+        """
+
+        # Order multiples
+        if multiples:
+            quantity = int(math.ceil(quantity / self.multipe) * self.multiple)
+
+        # Minimum ordering requirement
+        if moq and self.minimum > quantity:
+            quantity = self.minimum
+
+        pb_found = False
+        pb_quantity = -1
+        pb_cost = 0.0
+
+        for pb in self.price_breaks.all():
+            # Ignore this pricebreak!
+            if pb.quantity > quantity:
+                continue
+
+            pb_found = True
+
+            # If this price-break quantity is the largest so far, use it!
+            if pb.quantity > pb_quantity:
+                pb_quantity = pb.quantity
+                pb_cost = pb.cost
+
+        # No appropriate price-break found - use the single cost!
+        if pb_found:
+            cost = pb_cost * quantity
+        else:
+            cost = self.single_price * quantity
+
+        return cost + self.base_cost
+
     def __str__(self):
         return "{sku} - {supplier}".format(
             sku=self.SKU,
@@ -514,8 +565,11 @@ class SupplierPriceBreak(models.Model):
     """
 
     part = models.ForeignKey(SupplierPart, on_delete=models.CASCADE, related_name='price_breaks')
-    quantity = models.PositiveIntegerField(validators=[MinValueValidator(0)])
+
-    cost = models.DecimalField(max_digits=10, decimal_places=3)
+    # At least 2 units are required for a 'price break' - Otherwise, just use single-price!
+    quantity = models.PositiveIntegerField(validators=[MinValueValidator(2)])
+
+    cost = models.DecimalField(max_digits=10, decimal_places=3, validators=[MinValueValidator(0)])
 
     class Meta:
         unique_together = ("part", "quantity")

InvenTree/part/serializers.py

@@ -1,7 +1,7 @@
 from rest_framework import serializers
 
 from .models import Part, PartCategory, BomItem
-from .models import SupplierPart
+from .models import SupplierPart, SupplierPriceBreak
 
 from company.serializers import CompanyBriefSerializer
 
@@ -104,3 +104,15 @@ class SupplierPartSerializer(serializers.ModelSerializer):
             'manufacturer',
             'MPN',
         ]
+
+
+class SupplierPriceBreakSerializer(serializers.ModelSerializer):
+
+    class Meta:
+        model = SupplierPriceBreak
+        fields = [
+            'pk',
+            'part',
+            'quantity',
+            'cost'
+        ]

InvenTree/part/views.py

@@ -341,7 +341,6 @@ class SupplierPartCreate(AjaxCreateView):
     form_class = EditSupplierPartForm
     ajax_template_name = 'modal_form.html'
     ajax_form_title = 'Create new Supplier Part'
-    template_name = 'company/partcreate.html'
     context_object_name = 'part'
 
     def get_initial(self):