neatoDeploy/app/neato_auto_loader.php

<?php 
/**
 * Neato Auto loader PSR4
 * 
 * PHP version 8.3
 * 
 * @category Util
 * @package  Neato
 * @author   http://php-fig.org/ <info@php-fig.org>
 * @license  https://mit-license.org/ MIT License
 * @link     https://github.com/php-fig/fig-standards/blob/master/accepted/PSR-4-autoloader-examples.md
 */

/**
 *  Auto loader, uses namespace to guess where class file live.
 * 
 * @category Util
 * @package  Neato
 * @author   http://php-fig.org/ <info@php-fig.org>
 * @license  https://mit-license.org/ MIT License
 * @link     https://github.com/php-fig/fig-standards/blob/master/accepted/PSR-4-autoloader-examples.md
 */
class Neato_Auto_Loader
{

    /**
     * An associative array where the key is a namespace prefix and the value
     * is an array of base directories for classes in that namespace.
     *
     * @var array
     */
    protected $prefixes = [];

    /**
     * Register loader with SPL autoloader stack.
     *
     * @return void
     */
    public function register()
    {
        spl_autoload_register(array($this, 'loadClass'));
    }

    /**
     * Is class loaded, yet?
     * 
     * @param string $prefix holds global data of namespaces
     * 
     * @return bool
     */
    public function isLoaded(string $prefix): bool
    {
        $prefix = trim($prefix, '\\') . '\\';
        return (isset($this->prefixes[$prefix])) ? true : false;    
    }
  
    /**
     * Get List of loaded prefixes containing namespace/class.
     * 
     * @return array
     */
    public function getList(): array
    {
        return $this->prefixes;
    }
  
    /**
     * Adds a base directory for a namespace prefix.
     *
     * @param string $prefix   The namespace prefix.
     * @param string $base_dir A base directory for class files in the
     *                         namespace.
     * @param bool   $prepend  If true, prepend the base directory to the stack
     *                         instead of appending it; this causes it to be
     *                         searched first rather than last.                    
     * 
     * @return void
     */
    public function addNamespace(string $prefix, string $base_dir, bool $prepend = false): void
    {
        $prefix = trim($prefix, '\\') . '\\';
        $base_dir = rtrim($base_dir, DIRECTORY_SEPARATOR) . '/';
        if (isset($this->prefixes[$prefix]) === false) {
            $this->prefixes[$prefix] = array();
        }
        if ($prepend) {
            array_unshift($this->prefixes[$prefix], $base_dir);
        } else {
            array_push($this->prefixes[$prefix], $base_dir);
        }
    }

    /**
     * Loads the class file for a given class name.
     *
     * @param string $class The fully-qualified class name.
     * 
     * @return mixed The mapped file name on success, or boolean false on
     * failure.
     */
    public function loadClass(string $class)
    {
        /**
         * Semi-Fix for non-namespaced classes
         */
        if (! strrpos($class, '\\')) {
            return ($this->loadMappedFile($class . '\\', $class));
        }
        $prefix = $class;
        while (false !== $pos = strrpos($prefix, '\\')) {
            $prefix = substr($class, 0, $pos + 1);
            $relative_class = substr($class, $pos + 1);
            $mapped_file = $this->loadMappedFile($prefix, $relative_class);
            if ($mapped_file) {
                return $mapped_file;
            }
            $prefix = rtrim($prefix, '\\');
        }
        return false;
    }

    /**
     * Load the mapped file for a namespace prefix and relative class.
     *
     * @param string $prefix         The namespace prefix.
     * @param string $relative_class The relative class name.
     * 
     * @return mixed Boolean false if no mapped file can be loaded, or the
     * name of the mapped file that was loaded.
     */
    protected function loadMappedFile(string $prefix, string $relative_class)
    {
        if (isset($this->prefixes[$prefix]) === false) {
            return false;
        }
        foreach ($this->prefixes[$prefix] as $base_dir) {
            $file = $base_dir
            . str_replace('\\', '/', $relative_class)
            . '.php';
            if ($this->requireFile($file)) {
                return $file;
            }
        }
        return false;
    }

    /**
     * If a file exists, require it from the file system.
     *
     * @param string $file The file to require.
     * 
     * @return bool True if the file exists, false if not.
     */
    protected function requireFile(string $file): bool
    {
        if (file_exists($file)) {
            include $file;
            return true;
        }
        return false;
    }

}