Design an extensible poker-hand evaluator

Design and implement an object-oriented solution for a simplified 2-player poker-like game called Camel Cards.

Game rules

• There are two players . Each player has a hand of exactly 4 cards .
• Card labels are one of: 9, 8, 7, 6, 5, 4, 3, 2, 1 (where 9 is highest , 1 is lowest ).
• A hand is classified into exactly one hand type. From strongest to weakest , the types are:
  1. Four of a kind : all four cards the same (e.g., 9999 )
  2. Two pair : two cards the same + two cards the same (e.g., 2332 )
  3. Three of a kind : three cards the same + one different card (e.g., 9998 )
  4. One pair : two cards the same + two distinct others (e.g., 5233 )
  5. High card : all cards distinct (e.g., 2345 )

Note: This ordering is intentional (e.g., any two-pair beats any three-of-a-kind).

Tie-breaking (ordering rules)

1. Hands are primarily ordered by hand type (stronger type wins).
2. If both hands have the same type , compare cards from most recently dealt to first dealt (i.e., right-to-left ) without sorting the hand .
   • Compare the rightmost card values; higher value wins.
   • If equal, continue moving left.
   • If all four positions are equal, it’s a tie.

Task

Implement:

evaluate(hand1, hand2) -> "HAND_1" | "HAND_2" | "TIE"

Where each hand can be represented as a 4-character string like "2332" or an array/list of 4 card labels.

Design requirement

In the future, many more hand types will be introduced. Design your solution to make it easy to add new hand types without rewriting the evaluator logic.