Hi and welcome to team Gilded Rose. As you know, we are a small inn with a prime location in a prominent city ran by a friendly innkeeper named Allison. We also buy and sell only the finest goods. Unfortunately, our goods are constantly degrading in quality as they approach their sell by date. We have a system in place that updates our inventory for us. It was developed by a no-nonsense type named Leeroy, who has moved on to new adventures. Your task is to add the new feature to our system so that we can begin selling a new category of items. First an introduction to our system:
- All items have a SellIn value which denotes the number of days we have to sell the item
- All items have a Quality value which denotes how valuable the item is
- At the end of each day our system lowers both values for every item
Pretty simple, right? Well this is where it gets interesting:
- Once the sell by date has passed, Quality degrades twice as fast
- The Quality of an item is never negative
- “Aged Brie” actually increases in Quality the older it gets
- The Quality of an item is never more than 50
- “Sulfuras”, being a legendary item, never has to be sold or decreases in Quality
- “Backstage passes”, like aged brie, increases in Quality as its SellIn value approaches;
- Quality increases by 2 when there are 11 days or less and by 3 when there are 6 days or less but
- Quality drops to 0 after the concert
Refactor the code to accommodate the new feature while making sure that the existing functionality is not broken.
Several refactorings were applied to the code to make it more readable and maintainable:
- Create constants for each integer and string value used in the code.
- A function has been created for each item with its logic to have it divided.
- Class Item becomes an abstract class and each type of item inherits from it.
- Each item has its own logic to update its quality and sellIn.
- Also value objects have been created to separate the logic of each field of the item.