Binary Search Tree with PHP

BinarySearchTree.php

<?php
/**
 * Created by PhpStorm.
 * User: adriano
 * Date: 10/11/19
 * Time: 20:17
 */

class Node {

	private $left;
	private $right;
	private $data;

	public function __construct( $data ) {
		$this->data = $data;
	}

	public function setLeft( Node $node ) {
		$this->left = $node;
	}

	public function getLeft() {
		return $this->left;
	}

	public function setRight( Node $node ) {
		$this->right = $node;
	}

	public function getRight() {
		return $this->right;
	}

	public function getData() {
		return $this->data;
	}
}

class binarySearchTree {

	private $root;

	public function insert( $value ) {
		$node = new Node( $value );

		if ( ! $this->root ) {
			$this->root = $node;

			return;
		}

		$this->insertNode( $this->root, $node );
	}

	public function search( $value ) {
		return $this->searchNode( $this->root, $value );
	}

	private function searchNode( $currentNode, $value ) {
		if ( $currentNode->getData() === $value ) {
			return true;
		}

		if ( $value < $currentNode->getData() && $currentNode->getLeft() ) {
			return $this->searchNode( $currentNode->getLeft(), $value );
		}

		if ( $value > $currentNode->getData() && $currentNode->getRight() ) {
			return $this->searchNode( $currentNode->getRight(), $value );
		}

		return false;
	}

	private function insertNode( $currentNode, $node ) {
		if ( $node->getData() < $currentNode->getData() ) {
			if ( ! $currentNode->getLeft() ) {
				$currentNode->setLeft( $node );
			}

			$this->insertNode( $currentNode->getLeft(), $node );
		}

		if ( $node->getData() > $currentNode->getData() ) {
			if ( ! $currentNode->getRight() ) {
				$currentNode->setRight( $node );
			}

			$this->insertNode( $currentNode->getRight(), $node );
		}
	}
}

$binarySearchTree = new binarySearchTree();
$binarySearchTree->insert( 10 );
$binarySearchTree->insert( 6 );
$binarySearchTree->insert( 18 );
$binarySearchTree->insert( 4 );
$binarySearchTree->insert( 8 );
$binarySearchTree->insert( 15 );
$binarySearchTree->insert( 21 );
$result = $binarySearchTree->search( 50 );
$test = 1;