Cha Loader

gistfile1.aw

<?php
/**
 * Autoloads classes using the SPL library and the directory model given.
 * Contains support for namespaces.
 * 
 * @author Tyler(Chacha)
 * @package Cha
 */
class Cha_Loader
{
    /**
     * Include path for the script to look in
     * @var string
     */
    public $include_path = "";
    private $directory_model = array();
    private $extension = array();

    /**
     * Constructs the Autoloader
     * @param string $include_path The topmost include path for the application
     * @param bool $auto_register Whether to automatically register the Autoloader
     * or let the user manually register with Autoloader::register();
     */
    public function __construct($directory_model, $extension = "php", $include_path="", $auto_register=true)
    {
        $this->directory_model = $directory_model;

        // Remove a dot at the beginning of the file extension
        if(strpos($extension, ".") === 0)
        {
            $this->extension = substr($extension, 0);
        }
        else
        {
            $this->extension = $extension;
        }

        if(count($directory_model) == 0)
        {
            throw new Exception("No Directories Defined");
        }

        if($auto_register == true)
        {
            $this->registerAutoloader();
        }

        if(empty($include_path))
        {
            $include_path = get_include_path();
        }
        $this->include_path = $include_path;
    }

    /**
     * Register the Autoloader with the SPL Autoload Queue
     */
    public function registerAutoloader()
    {
        spl_autoload_register(array($this, "loadClass"));
    }

    /**
     * Attempts to load the class based on the directory structure given
     * @param string $class_name
     * @return bool True on Success, False on Failure
     */
    public function loadClass($class_name)
    {

        if(strpos($class_name, "\\") === 0)
        {
            $class_name = substr($class_name, 1);
        }

        $include_path = "";
        
        // First Check for Namespaces
        if(strpos($class_name, "\\") !== FALSE)
        {
            $namespace = substr($class_name, 0, strrpos($class_name, "\\"));
            $class_name = substr(substr($class_name, strrpos($class_name, "\\")), 1);
        }
        else
        {
            $namespace = "base";
        }
        
        if(array_key_exists($namespace, $this->directory_model))
        {

            // Check if the value is an array of paths
            if(is_array($this->directory_model[$namespace]))
            {

                // Try to include each file
                $statusCode = false;
                foreach($this->directory_model[$namespace] as $path)
                {
                    if($this->includeFile($path, $class_name) == true)
                    {
                        $statusCode = true;
                        break;
                    }
                }

                return $statusCode;
            }
            else
            {
                // Include the path via a pre-defined model
                return $this->includeFile($this->directory_model[$namespace], $class_name);
            }

        }
        else
        {
            // Include the path using the Namespace as a directory inside the include path
            return $this->includeFile($this->include_path . $namespace ."/", $class_name);
        }
        
    }

    private function includeFile($directory, $class_name)
    {
        $include_path = $this->buildFilePath($directory, $class_name);

        if(file_exists($include_path))
        {
            include($include_path);
            return true;
        }
        else
        {
            return false;
        }
    }

    private function buildFilePath($directory, $class_name)
    {
        return $directory . $class_name . "." . $this->extension;
    }
}