Depend on Abstractions, not Concretions (Framework)

doa.php

<?php

abstract class Player {
    public abstract function play();
}

class Human extends Player {
    public function play() {
        echo "Human player makes a move.\n";
    }
}

class Computer extends Player {
    public function play() {
        echo "Computer player makes a move.\n";
    }
}

class Round {
    private Player $player1;
    private Player $player2;

    public function __construct(Player $player1, Player $player2) {
        $this->player1 = $player1;
        $this->player2 = $player2;
    }

    public function playRound() {
        $this->player1->play();
        $this->player2->play();
        echo "Determine winner or tie based on game rules.\n";
    }
}

$humanPlayer = new Human();
$computerPlayer = new Computer();

$round = new Round($humanPlayer, $computerPlayer);
$round->playRound();