diff --git a/TypeScript/src/gilded-rose.ts b/TypeScript/src/gilded-rose.ts
index 3ea3db5f..7a66f877 100644
--- a/TypeScript/src/gilded-rose.ts
+++ b/TypeScript/src/gilded-rose.ts
@@ -4,7 +4,7 @@ export class Item {
   sellIn: number
   quality: number
 
-  constructor(name, sellIn, quality) {
+  constructor(name: string, sellIn: number, quality: number) {
     this.name = name
     this.sellIn = sellIn
     this.quality = quality
@@ -12,6 +12,7 @@ export class Item {
 
   static maxQualityThreshold = 50
   static minQualityThreshold = 0
+  static legendaryQuality = 80
 }
 
 export class GildedRose {
@@ -21,95 +22,79 @@ export class GildedRose {
     this.items = items
   }
 
-  // est périmité ?
   isOutdated(item: Item) {
     return item.sellIn < 0
   }
 
-  isNormalProduct(item: Item) {
-    return (
-      item.name !== 'Aged Brie' &&
-      item.name !== 'Backstage passes to a TAFKAL80ETC concert' &&
-      item.name !== 'Sulfuras, Hand of Ragnaros'
-    )
-  }
-
-  isLegendayProduct(item: Item) {
-    return item.name === 'Sulfuras, Hand of Ragnaros'
-  }
-
   incrementQuality(item: Item) {
-    if (item.quality < Item.maxQualityThreshold) {
-      return item.quality + 1
-    }
-    return item.quality
+    return item.quality < Item.maxQualityThreshold ? item.quality + 1 : item.quality
   }
 
   decrementQuality(item: Item) {
-    if (item.quality <= Item.minQualityThreshold) {
-      return item.quality
-    }
-    return item.quality - 1
+    return item.quality > Item.minQualityThreshold ? item.quality - 1 : item.quality
   }
 
   updateQuality() {
-    this.items.forEach(item => {
-      //LEGENDARY
-      if (this.isLegendayProduct(item)) {
-        item.quality = 80
-        return
-      }
-      const currentProductName = item.name
-
-      // NORMAL PRODUCT
-      if (this.isNormalProduct(item)) {
-        item.sellIn = item.sellIn - 1
-
-        if (this.isOutdated(item)) {
-          item.quality = this.decrementQuality(item)
-          item.quality = this.decrementQuality(item)
-          return
-        }
-
-        item.quality = this.decrementQuality(item)
-        return
-      }
-
-      // BACKSTAGE
-      if (currentProductName === 'Backstage passes to a TAFKAL80ETC concert') {
-        item.quality = this.incrementQuality(item)
-
-        if (item.sellIn < 11) {
-          item.quality = this.incrementQuality(item)
-        }
-
-        if (item.sellIn < 6) {
-          item.quality = this.incrementQuality(item)
-        }
-
-        item.sellIn = item.sellIn - 1
-
-        if (item.sellIn <= 0) {
-          item.quality = 0
-          return
-        }
-
-        return
-      }
-
-      // AGED BRIE
-      if (currentProductName === 'Aged Brie') {
-        item.quality = this.incrementQuality(item)
-        item.sellIn = item.sellIn - 1
-        if (!this.isOutdated(item)) {
-          return
-        }
-
-        item.quality = this.incrementQuality(item)
-        return
+    return this.items.map(item => {
+      switch (item.name) {
+        case 'Sulfuras, Hand of Ragnaros':
+          this.updateLegendaryProduct(item)
+          return item
+        case 'Aged Brie':
+          this.updateAgedBrie(item)
+          return item
+        case 'Backstage passes to a TAFKAL80ETC concert':
+          this.updateBackstageProduct(item)
+          return item
+        default:
+          this.updateNormalProduct(item)
+          return item
       }
     })
+  }
 
-    return this.items
+  private updateLegendaryProduct(item: Item) {
+    item.quality = Item.legendaryQuality
+  }
+
+  private updateAgedBrie(item: Item) {
+    //
+    item.sellIn = item.sellIn - 1
+
+    item.quality = this.incrementQuality(item)
+
+    if (!this.isOutdated(item)) {
+      return
+    }
+
+    item.quality = this.incrementQuality(item)
+
+    return { ...item, sellIn: item.sellIn - 1, quality: 0 }
+  }
+
+  private updateBackstageProduct(item: Item) {
+    item.quality = this.incrementQuality(item)
+
+    if (item.sellIn < 11) {
+      item.quality = this.incrementQuality(item)
+    }
+
+    if (item.sellIn < 6) {
+      item.quality = this.incrementQuality(item)
+    }
+
+    item.sellIn = item.sellIn - 1
+
+    if (item.sellIn <= 0) {
+      item.quality = 0
+    }
+  }
+
+  private updateNormalProduct(item: Item) {
+    item.sellIn = item.sellIn - 1
+    item.quality = this.decrementQuality(item)
+    if (this.isOutdated(item)) {
+      item.quality = this.decrementQuality(item)
+    }
   }
 }
diff --git a/TypeScript/src/test/golden-master-text-test.ts b/TypeScript/src/test/golden-master-text-test.ts
index ac1bf970..aa125f9d 100644
--- a/TypeScript/src/test/golden-master-text-test.ts
+++ b/TypeScript/src/test/golden-master-text-test.ts
@@ -13,13 +13,13 @@ export const itemsGoldenMaster = [
   new Item('Conjured Mana Cake', 3, 6),
 ]
 
-export const gildedRose = new GildedRose(itemsGoldenMaster)
-const days = 2
-for (let i = 0; i < days; i++) {
-  console.log('-------- day ' + i + ' --------')
-  console.log('name, sellIn, quality')
-  itemsGoldenMaster.forEach(element => {
-    console.log(element.name + ' ' + element.sellIn + ' ' + element.quality)
-  })
-  console.log()
-}
+// export const gildedRose = new GildedRose(itemsGoldenMaster)
+// const days = 2
+// for (let i = 0; i < days; i++) {
+//   console.log('-------- day ' + i + ' --------')
+//   console.log('name, sellIn, quality')
+//   itemsGoldenMaster.forEach(element => {
+//     console.log(element.name + ' ' + element.sellIn + ' ' + element.quality)
+//   })
+//   console.log()
+// }