products/models.py: add basic product image classes

products/models.py

@@ -1,5 +1,7 @@
 import logging
 import re
+from enum import Enum
+import os.path
 
 from django.conf import settings
 from django.db import models
@@ -38,3 +40,33 @@ class Product(models.Model):
         }
 
 
+class ProductImageFormat(Enum):
+    THUMB_PNG = 'thumb.png'
+    LARGE_JPG = 'large.jpg'
+    LARGE_PNG = 'large.png'
+    MED_JPG = 'med.jpg'
+    MED_PNG = 'med.png'
+
+
+class ProductImage:
+    THUMB_DIR = os.path.join(settings.ASSET_DIR, 'products/thumbs')
+    THUMB_URL = '/images/products/thumbs'
+    # ordered by thumbnail preference
+    VIEW_TYPES = ['C', '3Q', '3QL', '3QR', '3QRL', 'P', 'PL', 'P2', 'P2L',
+                  'F3Q', 'L', 'PLA', 'PPS', 'PPS_WORN', 'PLD', 'OS', 'OSL',
+                  'T', 'TL', 'PACK', 'F', 'B', 'INT', 'ALT_INT', 'FLR',
+                  'FRONT', 'BACK']
+
+    @staticmethod
+    def get_image_path(sap, image_format):
+        for view in ProductImage.VIEW_TYPES:
+            path = os.path.join(ProductImage.THUMB_DIR,
+                                '{}_{}-{}'.format(sap, view, image_format.value))
+            if os.path.isfile(path):
+                return path
+
+    @staticmethod
+    def get_image_url(sap, image_format):
+        path = ProductImage.get_image_path(sap, image_format)
+        if path:
+            return path.replace(ProductImage.THUMB_DIR, ProductImage.THUMB_URL)