Extract ServerConfigGroup from Server

this API isn't very nice, but it's pretty much the same as the original, and at least this can be _kinda_ unit-tested...

src/ServerConfigGroup.php

@@ -0,0 +1,128 @@
+<?php
+
+/*
+ *
+ *  ____            _        _   __  __ _                  __  __ ____
+ * |  _ \ ___   ___| | _____| |_|  \/  (_)_ __   ___      |  \/  |  _ \
+ * | |_) / _ \ / __| |/ / _ \ __| |\/| | | '_ \ / _ \_____| |\/| | |_) |
+ * |  __/ (_) | (__|   <  __/ |_| |  | | | | | |  __/_____| |  | |  __/
+ * |_|   \___/ \___|_|\_\___|\__|_|  |_|_|_| |_|\___|     |_|  |_|_|
+ *
+ * This program is free software: you can redistribute it and/or modify
+ * it under the terms of the GNU Lesser General Public License as published by
+ * the Free Software Foundation, either version 3 of the License, or
+ * (at your option) any later version.
+ *
+ * @author PocketMine Team
+ * @link http://www.pocketmine.net/
+ *
+ *
+*/
+
+declare(strict_types=1);
+
+namespace pocketmine;
+
+use pocketmine\utils\Config;
+use function array_key_exists;
+use function getopt;
+use function is_bool;
+use function strtolower;
+
+final class ServerConfigGroup{
+
+	/** @var Config */
+	private $pocketmineYml;
+	/** @var Config */
+	private $serverProperties;
+
+	/**
+	 * @var mixed[]
+	 * @phpstan-var array<string, mixed>
+	 */
+	private $propertyCache = [];
+
+	public function __construct(Config $pocketmineYml, Config $serverProperties){
+		$this->pocketmineYml = $pocketmineYml;
+		$this->serverProperties = $serverProperties;
+	}
+
+	/**
+	 * @param mixed  $defaultValue
+	 *
+	 * @return mixed
+	 */
+	public function getProperty(string $variable, $defaultValue = null){
+		if(!array_key_exists($variable, $this->propertyCache)){
+			$v = getopt("", ["$variable::"]);
+			if(isset($v[$variable])){
+				$this->propertyCache[$variable] = $v[$variable];
+			}else{
+				$this->propertyCache[$variable] = $this->pocketmineYml->getNested($variable);
+			}
+		}
+
+		return $this->propertyCache[$variable] ?? $defaultValue;
+	}
+
+	public function getConfigString(string $variable, string $defaultValue = "") : string{
+		$v = getopt("", ["$variable::"]);
+		if(isset($v[$variable])){
+			return (string) $v[$variable];
+		}
+
+		return $this->serverProperties->exists($variable) ? (string) $this->serverProperties->get($variable) : $defaultValue;
+	}
+
+	public function setConfigString(string $variable, string $value) : void{
+		$this->serverProperties->set($variable, $value);
+	}
+
+	public function getConfigInt(string $variable, int $defaultValue = 0) : int{
+		$v = getopt("", ["$variable::"]);
+		if(isset($v[$variable])){
+			return (int) $v[$variable];
+		}
+
+		return $this->serverProperties->exists($variable) ? (int) $this->serverProperties->get($variable) : $defaultValue;
+	}
+
+	public function setConfigInt(string $variable, int $value) : void{
+		$this->serverProperties->set($variable, $value);
+	}
+
+	public function getConfigBool(string $variable, bool $defaultValue = false) : bool{
+		$v = getopt("", ["$variable::"]);
+		if(isset($v[$variable])){
+			$value = $v[$variable];
+		}else{
+			$value = $this->serverProperties->exists($variable) ? $this->serverProperties->get($variable) : $defaultValue;
+		}
+
+		if(is_bool($value)){
+			return $value;
+		}
+		switch(strtolower($value)){
+			case "on":
+			case "true":
+			case "1":
+			case "yes":
+				return true;
+		}
+
+		return false;
+	}
+
+	public function setConfigBool(string $variable, bool $value) : void{
+		$this->serverProperties->set($variable, $value ? "1" : "0");
+	}
+
+	public function save() : void{
+		if($this->serverProperties->hasChanged()){
+			$this->serverProperties->save();
+		}
+		if($this->pocketmineYml->hasChanged()){
+			$this->pocketmineYml->save();
+		}
+	}
+}