Implement initial laptop allocation logic and user input handling

Author: Geraldine-Edwards

implement-laptop-allocation/laptop_allocaton.py

@@ -1,6 +1,7 @@
+import sys
 from dataclasses import dataclass
 from enum import Enum
-from typing import List
+from typing import List, Dict
 
 class OperatingSystem(Enum):
     MACOS = "macOS"
@@ -12,7 +13,7 @@ class Person:
     name: str
     age: int
     # Sorted in order of preference, most preferred is first.
-    preferred_operating_system: List[OperatingSystem]
+    preferred_operating_systems: List[OperatingSystem]
 
 
 @dataclass(frozen=True)
@@ -23,5 +24,83 @@ class Laptop:
     screen_size_in_inches: float
     operating_system: OperatingSystem
 
+# In the prep, there was an exercise around finding possible laptops for a group of people.
 
-def allocate_laptops(people: List[Person], laptops: List[Laptop]) -> Dict[Person, Laptop]:
+# Your exercise is to extend this to actually allocate laptops to the people.
+# Every person should be allocated exactly one laptop.
+
+# If we define “sadness” as the number of places down in someone’s ranking the operating system the ended
+# up with (i.e. if your preferences were [UBUNTU, ARCH, MACOS] and you were allocated a MACOS 
+# machine your sadness would be 2), we want to minimise the total sadness of all people. 
+# If we allocate someone a laptop with an operating system not in their preferred list, 
+# treat them as having a sadness of 100.
+
+laptops_list: List[Laptop] = [
+    Laptop(id=1, manufacturer="Dell", model="XPS", screen_size_in_inches=13, operating_system=OperatingSystem.ARCH),
+    Laptop(id=2, manufacturer="Dell", model="XPS", screen_size_in_inches=15, operating_system=OperatingSystem.UBUNTU),
+    Laptop(id=3, manufacturer="Dell", model="XPS", screen_size_in_inches=15, operating_system=OperatingSystem.UBUNTU),
+    Laptop(id=4, manufacturer="Apple", model="MacBook", screen_size_in_inches=13, operating_system=OperatingSystem.MACOS),
+    Laptop(id=5, manufacturer="Apple", model="MacBook Air", screen_size_in_inches=13, operating_system=OperatingSystem.MACOS),
+    Laptop(id=6, manufacturer="Lenovo", model="ThinkPad", screen_size_in_inches=14, operating_system=OperatingSystem.ARCH),
+    Laptop(id=7, manufacturer="Asus", model="ZenBook", screen_size_in_inches=13, operating_system=OperatingSystem.UBUNTU),
+    Laptop(id=8, manufacturer="HP", model="Spectre", screen_size_in_inches=14, operating_system=OperatingSystem.MACOS),
+    Laptop(id=9, manufacturer="Apple", model="MacBook Pro", screen_size_in_inches=16, operating_system=OperatingSystem.MACOS),
+]
+
+people: List[Person] = [
+    Person(name="Imran", age=18, preferred_operating_systems=[OperatingSystem.UBUNTU, OperatingSystem.ARCH]),
+    Person(name="Eliza", age=34, preferred_operating_systems=[OperatingSystem.ARCH, OperatingSystem.MACOS]),
+    Person(name="Luke", age=26, preferred_operating_systems=[OperatingSystem.MACOS, OperatingSystem.UBUNTU, OperatingSystem.ARCH]),
+    Person(name="Abby", age=30, preferred_operating_systems=[OperatingSystem.MACOS]),
+    Person(name="Ger", age=51, preferred_operating_systems=[OperatingSystem.UBUNTU, OperatingSystem.MACOS]),
+]
+
+def user_prompt() -> Person:
+    try:
+        # strip() whitespace before processing (no need for str type here as input always returns a string)
+        name = input("Please enter your first name: ").strip()
+        if not name.isalpha():
+            raise ValueError("Name must contain only alphabetic characters.")
+
+        # strip() before converting to integer
+        age = int(input("Please enter your age: ").strip())
+        minimum_age = 18
+        if age < minimum_age: 
+            raise ValueError("Age must be 18 or over.")
+
+
+        # define valid OS options
+        valid_os = [os.value for os in OperatingSystem]
+
+        # prompt the user to enter OS preferences in order of preference (no need for str type here)
+        preferred_os = input(f"Please enter your preferred operating systems in order of preference, separated by commas (e.g., {', '.join(valid_os)}): ").strip()
+
+        # split and validate the OS
+        preferred_os_list = [os.strip() for os in preferred_os.split(",")]
+        preferred_os_enum = []
+        for os_name in preferred_os_list:
+            if os_name not in valid_os:
+                raise ValueError(f"Invalid operating system: {os_name}")
+        # convert to enum
+            preferred_os_enum.append(OperatingSystem(os_name))
+
+        return Person(name=name, age=age, preferred_operating_systems=preferred_os_enum)
+
+    # throw an error and exit for invalid age and os input
+    except ValueError as error:
+        print(f"Invalid input: {error}", file=sys.stderr)
+        sys.exit(1)
+
+
+def find_possible_laptops(available_laptops: List[Laptop], current_person: Person) -> List[Laptop]:
+    return [
+        laptop for laptop in available_laptops
+        if laptop.operating_system in current_person.preferred_operating_systems
+    ]
+
+# allocated sequentially, in a first come first served order
+def allocate_laptops_sequentially(people: List[Person], laptops: List[Laptop]) -> Dict[Person, Laptop]:
+   """
+    Allocate laptops to people sequentially based on the order in the people list.
+    This approach respects the 'wait your turn' principle.
+    """