Once again... add a missing file...

src/pocketmine/block/utils/SignText.php

@@ -0,0 +1,130 @@
+<?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\block\utils;
+
+use function array_fill;
+use function array_pad;
+use function array_slice;
+use function count;
+use function explode;
+use function is_int;
+use function strpos;
+
+class SignText{
+	public const LINE_COUNT = 4;
+
+	/** @var string[] */
+	private $lines;
+
+	/**
+	 * @param string[] $lines
+	 * @throws \InvalidArgumentException
+	 */
+	public function __construct(?array $lines = null){
+		$this->setLines($lines ?? array_fill(0, self::LINE_COUNT, ""));
+	}
+
+	/**
+	 * Parses sign lines from the given string blob.
+	 * TODO: add a strict mode for this
+	 *
+	 * @param string $blob
+	 *
+	 * @return SignText
+	 * @throws \InvalidArgumentException if the text is not valid UTF-8
+	 */
+	public static function fromBlob(string $blob) : SignText{
+		return new self(array_slice(array_pad(explode("\n", $blob), self::LINE_COUNT, ""), 0, self::LINE_COUNT));
+	}
+
+	/**
+	 * Returns an array of lines currently on the sign.
+	 *
+	 * @return string[]
+	 */
+	public function getLines() : array{
+		return $this->lines;
+	}
+
+	/**
+	 * Sets the sign text.
+	 *
+	 * @param string[] $lines index-sensitive; omitting an index will leave it unchanged
+	 *
+	 * @throws \InvalidArgumentException if the array size is greater than 4
+	 * @throws \InvalidArgumentException if invalid keys (out of bounds or string) are found in the array
+	 */
+	public function setLines(array $lines) : void{
+		if(count($lines) > self::LINE_COUNT){
+			throw new \InvalidArgumentException("Expected at most 4 lines, got " . count($lines));
+		}
+		foreach($lines as $k => $line){
+			$this->checkLineIndex($k);
+			$this->setLine($k, $line);
+		}
+	}
+
+	private function checkLineIndex($index) : void{
+		if(!is_int($index)){
+			throw new \InvalidArgumentException("Index must be an integer");
+		}
+		if($index < 0 or $index >= self::LINE_COUNT){
+			throw new \InvalidArgumentException("Line index is out of bounds");
+		}
+	}
+
+	/**
+	 * Returns the sign line at the given offset.
+	 *
+	 * @param int $index
+	 *
+	 * @return string
+	 * @throws \InvalidArgumentException
+	 */
+	public function getLine(int $index) : string{
+		$this->checkLineIndex($index);
+		return $this->lines[$index];
+	}
+
+	/**
+	 * Sets the line at the given offset.
+	 *
+	 * @param int    $index
+	 * @param string $line
+	 *
+	 * @throws \InvalidArgumentException if the text is not valid UTF-8
+	 * @throws \InvalidArgumentException if the text contains a newline
+	 */
+	public function setLine(int $index, string $line) : void{
+		$this->checkLineIndex($index);
+		if(!mb_check_encoding($line, 'UTF-8')){
+			throw new \InvalidArgumentException("Line must be valid UTF-8 text");
+		}
+		if(strpos($line, "\n") !== false){
+			throw new \InvalidArgumentException("Line must not contain newlines");
+		}
+		//TODO: add length checks
+		$this->lines[$index] = $line;
+	}
+}