refactoring and adding more dependency injection through ioc container.

laravel/container.php

@@ -0,0 +1,94 @@
+<?php namespace Laravel;
+
+class Container {
+
+	/**
+	 * The resolved singleton instances.
+	 *
+	 * @var array
+	 */
+	private $singletons = array();
+
+	/**
+	 * The registered dependencies.
+	 *
+	 * @var array
+	 */
+	private $resolvers = array();
+
+	/**
+	 * Register a dependency and its resolver.
+	 *
+	 * The resolver function when the registered dependency is requested.
+	 *
+	 * <code>
+	 *		// Register a simple dependency
+	 *		$container->register('name', function() { return 'Fred'; });
+	 *
+	 *		// Register a dependency as a singleton
+	 *		$container->register('name', function() { return new Name; }, true);
+	 * </code>
+	 *
+	 * @param  string   $name
+	 * @param  Closure  $resolver
+	 * @return void
+	 */
+	public function register($name, $resolver, $singleton = false)
+	{
+		$this->resolvers[$name] = compact('resolver', 'singleton');
+	}
+
+	/**
+	 * Register a dependency as a singleton.
+	 *
+	 * @param  string   $name
+	 * @param  Closure  $resolver
+	 * @return void
+	 */
+	public function singleton($name, $resolver)
+	{
+		$this->register($name, $resolver, true);
+	}
+
+	/**
+	 * Register an instance as a singleton.
+	 *
+	 * @param  string  $name
+	 * @param  mixed   $instance
+	 * @return void
+	 */
+	public function instance($name, $instance)
+	{
+		$this->singletons[$name] = $instance;
+	}
+
+	/**
+	 * Resolve a dependency.
+	 *
+	 * The dependency's resolver will be called and its result will be returned.
+	 *
+	 * <code>
+	 *		// Resolver the "name" dependency
+	 *		$name = $container->resolve('name');
+	 * </code>
+	 *
+	 * @param  string  $name
+	 * @return mixed
+	 */
+	public function resolve($name)
+	{
+		if (array_key_exists($name, $this->singletons)) return $this->singletons[$name];
+
+		if ( ! array_key_exists($name, $this->resolvers))
+		{
+			throw new \Exception("Error resolving [$name]. No resolver has been registered in the container.");
+		}
+
+		$object = call_user_func($this->resolvers[$name]['resolver'], $this);
+
+		if ($this->resolvers[$name]['singleton']) $this->singletons[$name] = $object;
+
+		return $object;
+	}
+
+}