GildedRose-Refactoring-Kata/python/gilded_rose.py
2026-05-05 13:32:30 -07:00

130 lines
4.3 KiB
Python
Executable File

# -*- coding: utf-8 -*-
from dataclasses import dataclass
from typing import Protocol
class UpdateStrategy(Protocol):
"""Interface for per-item-type quality update logic."""
def update(self, item: "Item", days: int) -> None:
"""Mutate item.quality and item.sell_in to reflect `days` passing."""
...
class NormalStrategy:
"""
Default degradation strategy.
Quality decreases by 1 per day; by 2 per day once the sell date
has passed (sell_in < 0). Quality never falls below 0.
"""
def update(self, item: "Item", days: int) -> None:
for _ in range(days):
item.quality = max(0, item.quality - 1)
item.sell_in -= 1
if item.sell_in < 0:
item.quality = max(0, item.quality - 1)
class AgedBrieStrategy:
"""
Quality improvement strategy for Aged Brie.
Quality increases by 1 per day; by 2 per day once the sell date
has passed. Quality never exceeds 50.
"""
def update(self, item: "Item", days: int) -> None:
for _ in range(days):
item.quality = min(50, item.quality + 1)
item.sell_in -= 1
if item.sell_in < 0:
item.quality = min(50, item.quality + 1)
class BackstagePassStrategy:
"""
Quality strategy for backstage passes.
Quality increases as the concert approaches:
- +1/day when more than 10 days remain
- +2/day when 10 or fewer days remain
- +3/day when 5 or fewer days remain
Quality drops to 0 on concert day (sell_in == 0 at start of day)
and stays 0 afterwards. Quality never exceeds 50.
"""
def update(self, item: "Item", days: int) -> None:
for _ in range(days):
if item.sell_in <= 0:
# Concert day or past — pass is worthless
item.quality = 0
item.sell_in -= 1
continue
if item.sell_in <= 5:
item.quality = min(50, item.quality + 3)
elif item.sell_in <= 10:
item.quality = min(50, item.quality + 2)
else:
item.quality = min(50, item.quality + 1)
item.sell_in -= 1
class SulfurasStrategy:
"""
No-op strategy for Sulfuras, Hand of Ragnaros.
Legendary items never degrade and never need to be sold.
Neither quality nor sell_in is ever mutated.
"""
def update(self, item: "Item", days: int) -> None:
pass # legendary items are immutable; parameters required by Protocol
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":
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)