fix: refactored main class to subclass logics

python/gilded_rose.py

@@ -1,46 +1,88 @@
 # -*- coding: utf-8 -*-
 
-class GildedRose(object):
+class Item:
+    degradation_per_day: int = 1
+    quality_min_value: int = 0
+    quality_max_value: int = 50
     
+    def __init__(self, name, sell_in, quality):
+        assert quality >= self.quality_min_value
+        assert quality <= self.quality_max_value
+        self.name = name
+        self.sell_in = sell_in
+        self.quality = quality
+
+    def __new__(cls, name, sell_in, quality):
+        # If we are directly creating an Item, redirect to a mapped subclass
+        if cls is Item and name in items_mappings:
+            return super().__new__(items_mappings[name])
+        return super().__new__(cls)
+    
+    def daily_step(self):
+        if self.quality < 0:
+            return
+        
+        degradation = self.degradation_per_day
+        if self.sell_in < 0:
+            degradation *= 2
+        
+        self.quality = max(0, self.quality - degradation)
+        self.sell_in -= 1
+
+    def __repr__(self):
+        return "%s, %s, %s" % (self.name, self.sell_in, self.quality)
+
+
+class AgedBrie(Item):
+    name: str = "Aged Brie"
+    degradation_per_day: int = -1
+
+
+class BackstagePasses(Item):
+    name: str = "Backstage passes to a TAFKAL80ETC concert"
+    def daily_step(self):
+        if self.sell_in < 0:
+            self.quality = 0
+            return
+        elif 0 < self.sell_in < 6:
+            self.quality += 3
+        elif 6 < self.sell_in < 11:
+            self.quality += 2
+        else:
+            self.quality += 1
+
+        self.quality = min(50, self.quality)    
+        
+        super().daily_step()
+
+
+class Sulfuras(Item):
+    name: str = "Sulfuras, Hand of Ragnaros"
+    quality_max_value: int = 80
+    quality_min_value: int = 80
+    def __init__(self, name, sell_in, quality):
+        super().__init__(name, 0, 80)
+
+
+class Conjured(Item):
+    name: str = "Conjured"
+    def daily_step(self):
+        if self.quality < 50:
+            self.quality += 1
+        super().daily_step()
+
+
+items_mappings: dict[str, type[Item]] = {
+    "Aged Brie": AgedBrie,
+    "Backstage passes to a TAFKAL80ETC concert": BackstagePasses,
+    "Sulfuras, Hand of Ragnaros": Sulfuras,
+    "Conjured": Conjured,
+    }
+
+class GildedRose(object):
     def __init__(self, items):
         self.items = items
 
     def update_quality(self):
         for item in self.items:
-            if item.name != "Aged Brie" and item.name != "Backstage passes to a TAFKAL80ETC concert":
+            item.daily_step()
-                if item.quality > 0:
-                    if item.name != "Sulfuras, Hand of Ragnaros":
-                        item.quality = item.quality - 1
-            else:
-                if item.quality < 50:
-                    item.quality = item.quality + 1
-                    if item.name == "Backstage passes to a TAFKAL80ETC concert":
-                        if item.sell_in < 11:
-                            if item.quality < 50:
-                                item.quality = item.quality + 1
-                        if item.sell_in < 6:
-                            if item.quality < 50:
-                                item.quality = item.quality + 1
-            if item.name != "Sulfuras, Hand of Ragnaros":
-                item.sell_in = item.sell_in - 1
-            if item.sell_in < 0:
-                if item.name != "Aged Brie":
-                    if item.name != "Backstage passes to a TAFKAL80ETC concert":
-                        if item.quality > 0:
-                            if item.name != "Sulfuras, Hand of Ragnaros":
-                                item.quality = item.quality - 1
-                    else:
-                        item.quality = item.quality - item.quality
-                else:
-                    if item.quality < 50:
-                        item.quality = item.quality + 1
-
-
-class Item:
-    def __init__(self, name, sell_in, quality):
-        self.name = name
-        self.sell_in = sell_in
-        self.quality = quality
-
-    def __repr__(self):
-        return "%s, %s, %s" % (self.name, self.sell_in, self.quality)