Merge pull request #7 from effone/simple-di

Resolves #4 Dependency Injection Container

app/core/class/di.php

@@ -0,0 +1,125 @@
+<?php
+/**
+ * Elyzin - PHP based free forum software
+ * 
+ * @since 0.1.0
+ * @version 0.1.0
+ * @package Model : Dependency Injection
+ * @author Mustafa Magdi <https://medium.com/@MustafaMagdi>, Joe Mottershaw <https://medium.com/@joemottershaw>
+ * @source https://github.com/elyzin/elyzin Base repository
+ * @link http://elyz.in
+ * @copyright 2018 Elyzin
+ * @license MIT
+ * 
+ * @todo Namespace
+ * @todo Interface
+ */
+class DI
+{
+	/**
+	 * @var array
+	 */
+	protected $instances = [];
+
+	/**
+	 * @param      $abstract
+	 * @param null $concrete
+	 */
+	public function push($abstract, $concrete = null)
+	{
+		if ($concrete === null) {
+			$concrete = $abstract;
+		}
+		$this->instances[$abstract] = $concrete;
+	}
+
+	/**
+	 * @param       $abstract
+	 * @param array $values
+	 *
+	 * @return mixed|null|object
+	 * @throws Exception
+	 */
+	public function pull($abstract, $values = [])
+	{
+		// if we don't have it, just register it
+		if (!isset($this->instances[$abstract])) {
+			$this->set($abstract);
+		}
+
+		return $this->resolve($this->instances[$abstract], $values);
+	}
+
+	/**
+	 * resolve single
+	 *
+	 * @param $concrete
+	 * @param $values
+	 *
+	 * @return mixed|object
+	 * @throws Exception
+	 */
+	public function resolve($concrete, $values = [])
+	{
+		if ($concrete instanceof Closure) {
+			return $concrete($this, $values);
+		}
+
+		$reflector = new ReflectionClass($concrete);
+		// check if class is instantiable
+		if (!$reflector->isInstantiable()) {
+			throw new Exception("Class {$concrete} is not instantiable");
+		}
+
+		// get class constructor
+		$constructor = $reflector->getConstructor();
+		if (is_null($constructor)) {
+			// get new instance from class
+			return $reflector->newInstance();
+		}
+
+		// get constructor params
+		$parameters = $constructor->getParameters();
+		$dependencies = $this->getDependencies($parameters, $values);
+
+		// get new instance with dependencies resolved
+		return $reflector->newInstanceArgs($dependencies);
+	}
+
+	/**
+	 * get all dependencies resolved
+	 *
+	 * @param $parameters
+	 *
+	 * @return array
+	 * @throws Exception
+	 */
+	public function getDependencies($parameters, $values)
+	{
+		$dependencies = [];
+		foreach ($parameters as $parameter) {
+			// get the type hinted class
+			$dependency = $parameter->getClass();
+			if ($dependency === null) {
+				// check if the constructor parameter name exists as a key in the values array
+				if (array_key_exists($parameter->getName(), $values)) {
+				  // get default value of parameter
+					$dependencies[] = $values[$parameter->getName()];
+				} else {
+				  // check if default value for a parameter is available
+					if ($parameter->isDefaultValueAvailable()) {
+					// get default value of parameter
+						$dependencies[] = $parameter->getDefaultValue();
+					} else {
+						throw new Exception("Can not resolve class dependency {$parameter->name}");
+					}
+				}
+			} else {
+				// get dependency resolved
+				$dependencies[] = $this->get($dependency->name);
+			}
+		}
+
+		return $dependencies;
+	}
+}

app/core/func/site.php

@@ -14,8 +14,15 @@
 
 if (!defined("APP")) die(); // Deny direct access
 
-// Return preconfigured system paths
-// =========================================================================================================
+// Class autoloader
+spl_autoload_register(function($c){@include syspath('class').preg_replace('#\\\|_(?!.+\\\)#','/',$c).'.php';});
+
+/**
+ * Return preconfigured system paths
+ *
+ * @param [type] $target
+ * @return string
+ */
 function syspath($target){
 	$path = parse_ini_file(dirname(__DIR__).'/conf/syspath.ini',true);
 	foreach ($path as $key => $group) {
@@ -27,9 +34,15 @@ function syspath($target){
 	return false;
 }
 
-// Fetch Settings << Fetch user settings as well, avoid hardcoded ini path
-// =========================================================================================================
-function conf($node, $group = 'site'){
+/**
+ * Return Settings Values
+ *
+ * @param [type] $node // Settings name
+ * @param string $group // Settings Group Name
+ * @return mixed
+ * @todo Fetch user settings as well, avoid hardcoded ini path
+ */
+function conf(string $node, string $group = 'site'){
 	$settings = parse_ini_file(syspath('config').'basefact.ini',true);
 	if(!empty($settings[$group][$node])) return $settings[$group][$node];
 	return false;

public/index.php

@@ -41,16 +41,10 @@
 
 // Start a new or resume existing session
 session_start();
-
-// Class autoloader
-spl_autoload_register(function($c){@include syspath('class').preg_replace('#\\\|_(?!.+\\\)#','/',$c).'.php';});
 
-$db 	= new db();
-$me 	= new user();
-$clock 	= new clock();
-$file 	= new file();
-$log	= new log();
-$page 	= new page($pgen);
+$di 	= new DI();
+$me = $di->pull['user'];
+$page = $di->pull['page'];
 
 // Set timezone as per user preference
 if(!empty($me->pref('timezone'))){
@@ -84,4 +78,4 @@
 	$page->render('page_underdev', $msg)->flush();
 }
 // Template code gathered through script. Display final page
-$page->out();
+$page->out($pgen);