Bob

src/Bob.php

@@ -0,0 +1,57 @@
+<?php
+
+declare(strict_types=1);
+
+namespace App;
+
+final class Bob
+{
+    public const RESPONSE_DEFAULT = 'Whatever.';
+    public const RESPONSE_SAY_NOTHING = 'Fine. Be that way!';
+    public const RESPONSE_QUESTION = 'Sure.';
+    public const RESPONSE_YELLING = 'Whoa, chill out!';
+    public const RESPONSE_YELLING_QUESTION = 'Calm down, I know what I\'m doing!';
+
+    private string $input;
+
+    public static function saySomethingTo(string $input): self
+    {
+        return new self($input);
+    }
+
+    public function getResponse(): string
+    {
+        if ($this->input === '') {
+            return self::RESPONSE_SAY_NOTHING;
+        }
+
+        if ($this->isQuestion() && $this->isYelling()) {
+            return self::RESPONSE_YELLING_QUESTION;
+        }
+
+        if ($this->isQuestion()) {
+            return self::RESPONSE_QUESTION;
+        }
+
+        if ($this->isYelling()) {
+            return self::RESPONSE_YELLING;
+        }
+
+        return self::RESPONSE_DEFAULT;
+    }
+
+    final private function __construct(string $input)
+    {
+        $this->input = $input;
+    }
+
+    private function isQuestion(): bool
+    {
+        return (bool) preg_match('/.+\?/', $this->input);
+    }
+
+    private function isYelling(): bool
+    {
+        return (bool) preg_match('/.+!/', $this->input);
+    }
+}