GildedRose Refactoring

Java/src/main/java/com/gildedrose/GildedRose.java

@@ -1,62 +1,26 @@
 package com.gildedrose;
 
+import com.gildedrose.strategy.StrategyProvider;
+import com.gildedrose.strategy.UpdateStrategy;
+
 class GildedRose {
     Item[] items;
+    private final StrategyProvider strategyProvider;
 
     public GildedRose(Item[] items) {
         this.items = items;
+        this.strategyProvider = new StrategyProvider();
+    }
+
+    public GildedRose(Item[] items, StrategyProvider strategyProvider) {
+        this.items = items;
+        this.strategyProvider = strategyProvider;
     }
 
     public void updateQuality() {
-        for (int i = 0; i < items.length; i++) {
+        for (Item item : items) {
-            if (!items[i].name.equals("Aged Brie")
+            UpdateStrategy strategy = this.strategyProvider.getStrategyForItem(item);
-                    && !items[i].name.equals("Backstage passes to a TAFKAL80ETC concert")) {
+            strategy.update(item);
-                if (items[i].quality > 0) {
-                    if (!items[i].name.equals("Sulfuras, Hand of Ragnaros")) {
-                        items[i].quality = items[i].quality - 1;
-                    }
-                }
-            } else {
-                if (items[i].quality < 50) {
-                    items[i].quality = items[i].quality + 1;
-
-                    if (items[i].name.equals("Backstage passes to a TAFKAL80ETC concert")) {
-                        if (items[i].sellIn < 11) {
-                            if (items[i].quality < 50) {
-                                items[i].quality = items[i].quality + 1;
-                            }
-                        }
-
-                        if (items[i].sellIn < 6) {
-                            if (items[i].quality < 50) {
-                                items[i].quality = items[i].quality + 1;
-                            }
-                        }
-                    }
-                }
-            }
-
-            if (!items[i].name.equals("Sulfuras, Hand of Ragnaros")) {
-                items[i].sellIn = items[i].sellIn - 1;
-            }
-
-            if (items[i].sellIn < 0) {
-                if (!items[i].name.equals("Aged Brie")) {
-                    if (!items[i].name.equals("Backstage passes to a TAFKAL80ETC concert")) {
-                        if (items[i].quality > 0) {
-                            if (!items[i].name.equals("Sulfuras, Hand of Ragnaros")) {
-                                items[i].quality = items[i].quality - 1;
-                            }
-                        }
-                    } else {
-                        items[i].quality = items[i].quality - items[i].quality;
-                    }
-                } else {
-                    if (items[i].quality < 50) {
-                        items[i].quality = items[i].quality + 1;
-                    }
-                }
-            }
         }
     }
 }

Java/src/main/java/com/gildedrose/calculator/quality/QualityCalculator.java

@@ -0,0 +1,7 @@
+package com.gildedrose.calculator.quality;
+
+import com.gildedrose.Item;
+
+public interface QualityCalculator {
+    int calculate(Item item, int updatedSellIn);
+}

Java/src/main/java/com/gildedrose/calculator/quality/impl/AgedBrieQualityCalculator.java

@@ -0,0 +1,13 @@
+package com.gildedrose.calculator.quality.impl;
+
+import com.gildedrose.Item;
+import com.gildedrose.calculator.quality.QualityCalculator;
+
+public class AgedBrieQualityCalculator implements QualityCalculator {
+    @Override
+    public int calculate(Item item, int updatedSellIn) {
+        int increaseAmount = (updatedSellIn < 0) ? 2 : 1;
+        int newQuality = item.quality + increaseAmount;
+        return Math.min(50, newQuality);
+    }
+}

Java/src/main/java/com/gildedrose/calculator/quality/impl/BackstagePassQualityCalculator.java

@@ -0,0 +1,18 @@
+package com.gildedrose.calculator.quality.impl;
+
+import com.gildedrose.Item;
+import com.gildedrose.calculator.quality.QualityCalculator;
+
+public class BackstagePassQualityCalculator implements QualityCalculator {
+    @Override
+    public int calculate(Item item, int updatedSellIn) {
+        if (updatedSellIn < 0) {
+            return 0;
+        }
+
+        int qualityIncrease = 1 + (item.sellIn < 11 ? 1 : 0) + (item.sellIn < 6 ? 1 : 0);
+        int newQuality = item.quality + qualityIncrease;
+
+        return Math.min(50, newQuality);
+    }
+}

Java/src/main/java/com/gildedrose/calculator/quality/impl/DefaultQualityCalculator.java

@@ -0,0 +1,13 @@
+package com.gildedrose.calculator.quality.impl;
+
+import com.gildedrose.Item;
+import com.gildedrose.calculator.quality.QualityCalculator;
+
+public class DefaultQualityCalculator implements QualityCalculator {
+    @Override
+    public int calculate(Item item, int updatedSellIn) {
+        int decreaseAmount = (updatedSellIn < 0) ? 2 : 1;
+        int newQuality = item.quality - decreaseAmount;
+        return Math.max(0, newQuality);
+    }
+}

Java/src/main/java/com/gildedrose/calculator/quality/impl/SulfurasQualityCalculator.java

@@ -0,0 +1,11 @@
+package com.gildedrose.calculator.quality.impl;
+
+import com.gildedrose.Item;
+import com.gildedrose.calculator.quality.QualityCalculator;
+
+public class SulfurasQualityCalculator implements QualityCalculator {
+    @Override
+    public int calculate(Item item, int updatedSellIn) {
+        return item.quality;
+    }
+}

Java/src/main/java/com/gildedrose/calculator/sellIn/SellInCalculator.java

@@ -0,0 +1,7 @@
+package com.gildedrose.calculator.sellIn;
+
+import com.gildedrose.Item;
+
+public interface SellInCalculator {
+    int calculate(Item item);
+}

Java/src/main/java/com/gildedrose/calculator/sellIn/impl/StandardSellInCalculator.java

@@ -0,0 +1,11 @@
+package com.gildedrose.calculator.sellIn.impl;
+
+import com.gildedrose.Item;
+import com.gildedrose.calculator.sellIn.SellInCalculator;
+
+public class StandardSellInCalculator implements SellInCalculator {
+    @Override
+    public int calculate(Item item) {
+        return item.sellIn - 1;
+    }
+}

Java/src/main/java/com/gildedrose/calculator/sellIn/impl/SulfurasSellInCalculator.java

@@ -0,0 +1,11 @@
+package com.gildedrose.calculator.sellIn.impl;
+
+import com.gildedrose.Item;
+import com.gildedrose.calculator.sellIn.SellInCalculator;
+
+public class SulfurasSellInCalculator implements SellInCalculator {
+    @Override
+    public int calculate(Item item) {
+        return item.sellIn;
+    }
+}

Java/src/main/java/com/gildedrose/strategy/StrategyProvider.java

@@ -0,0 +1,51 @@
+package com.gildedrose.strategy;
+
+import com.gildedrose.Item;
+import com.gildedrose.calculator.quality.impl.AgedBrieQualityCalculator;
+import com.gildedrose.calculator.quality.impl.BackstagePassQualityCalculator;
+import com.gildedrose.calculator.quality.impl.DefaultQualityCalculator;
+import com.gildedrose.calculator.quality.impl.SulfurasQualityCalculator;
+import com.gildedrose.calculator.sellIn.impl.StandardSellInCalculator;
+import com.gildedrose.calculator.sellIn.impl.SulfurasSellInCalculator;
+import com.gildedrose.strategy.impl.ItemUpdateStrategy;
+
+import java.util.Map;
+
+public class StrategyProvider {
+
+    private final Map<String, UpdateStrategy> strategies;
+    private final UpdateStrategy defaultStrategy;
+
+    public static final String AGED_BRIE_NAME = "Aged Brie";
+    public static final String BACKSTAGE_NAME = "Backstage passes to a TAFKAL80ETC concert";
+    public static final String SULFURAS_NAME = "Sulfuras, Hand of Ragnaros";
+
+    public StrategyProvider() {
+        UpdateStrategy normalStrategy = new ItemUpdateStrategy(new DefaultQualityCalculator(), new StandardSellInCalculator());
+        UpdateStrategy agedBrieStrategy = new ItemUpdateStrategy(new AgedBrieQualityCalculator(), new StandardSellInCalculator());
+        Map<String, UpdateStrategy> strategyMap = getUpdateStrategyMap(agedBrieStrategy);
+        this.strategies = strategyMap;
+        this.defaultStrategy = normalStrategy;
+    }
+
+    public StrategyProvider(Map<String, UpdateStrategy> strategyMap, UpdateStrategy defaultStrategy) {
+        this.strategies = strategyMap;
+        this.defaultStrategy = defaultStrategy;
+    }
+
+    public UpdateStrategy getStrategyForItem(Item item) {
+        return strategies.getOrDefault(item.name, defaultStrategy);
+    }
+
+    private static Map<String, UpdateStrategy> getUpdateStrategyMap(UpdateStrategy agedBrieStrategy) {
+        UpdateStrategy backstageStrategy = new ItemUpdateStrategy(new BackstagePassQualityCalculator(), new StandardSellInCalculator());
+        UpdateStrategy sulfurasStrategy = new ItemUpdateStrategy(new SulfurasQualityCalculator(), new SulfurasSellInCalculator());
+
+        Map<String, UpdateStrategy> strategyMap = Map.of(
+            AGED_BRIE_NAME, agedBrieStrategy,
+            BACKSTAGE_NAME, backstageStrategy,
+            SULFURAS_NAME, sulfurasStrategy
+        );
+        return strategyMap;
+    }
+}

Java/src/main/java/com/gildedrose/strategy/UpdateStrategy.java

@@ -0,0 +1,7 @@
+package com.gildedrose.strategy;
+
+import com.gildedrose.Item;
+
+public interface UpdateStrategy {
+    void update(Item item);
+}

Java/src/main/java/com/gildedrose/strategy/impl/ItemUpdateStrategy.java

@@ -0,0 +1,25 @@
+package com.gildedrose.strategy.impl;
+
+import com.gildedrose.Item;
+import com.gildedrose.calculator.quality.QualityCalculator;
+import com.gildedrose.calculator.sellIn.SellInCalculator;
+import com.gildedrose.strategy.UpdateStrategy;
+
+public class ItemUpdateStrategy implements UpdateStrategy {
+
+    private final QualityCalculator qualityCalculator;
+    private final SellInCalculator sellinCalculator;
+
+    public ItemUpdateStrategy(QualityCalculator qualityCalculator, SellInCalculator sellinCalculator) {
+        this.qualityCalculator = qualityCalculator;
+        this.sellinCalculator = sellinCalculator;
+    }
+
+    @Override
+    public void update(Item item) {
+        int updatedSellIn = this.sellinCalculator.calculate(item);
+        int updatedQuality = this.qualityCalculator.calculate(item, updatedSellIn);
+        item.sellIn = updatedSellIn;
+        item.quality = updatedQuality;
+    }
+}

start_texttest.sh

@@ -1,7 +1,7 @@
 #!/bin/sh
 
 if [ ! -d "venv" ]; then
-    python -m venv venv
+    python3 -m venv venv
 fi
 venv/bin/pip install texttest
 venv/bin/texttest -d . -con "$@"

texttests/config.gr

@@ -22,7 +22,7 @@ diff_program:meld
 
 # Settings for the Java version using Gradle wrapped in a python script
 #executable:${TEXTTEST_HOME}/Java/texttest_rig.py
-#interpreter:python
+#interpreter:python3
 
 # Settings for the Java version using the classpath
 #executable:com.gildedrose.TexttestFixture
@@ -30,12 +30,12 @@ diff_program:meld
 # note you'll also need to update the file environment.gr with your classpath if you keep your classfiles somewhere unusual
 
 # Settings for the Kotlin version using Gradle wrapped in a python script
-#executable:${TEXTTEST_HOME}/Kotlin/texttest_rig.py
+executable:${TEXTTEST_HOME}/Kotlin/texttest_rig.py
-#interpreter:python
+interpreter:python3
 
 # Settings for the Ruby version
-executable:${TEXTTEST_HOME}/ruby/texttest_fixture.rb
+#executable:${TEXTTEST_HOME}/ruby/texttest_fixture.rb
-interpreter:ruby
+#interpreter:ruby
 
 # Settings for the C# Core version
 #executable:${TEXTTEST_HOME}/csharpcore/GildedRoseTests/bin/Debug/net8.0/GildedRoseTests