// define some services
$container[‘session_storage‘] = function ($c) {
    return new SessionStorage(‘SESSION_ID‘);
};


$container[‘session‘] = function ($c) {
    return new Session($c[‘session_storage‘]);
};

// get the session object
$session = $container[‘session‘];


// the above call is roughly equivalent to the following code:
// $storage = new SessionStorage(‘SESSION_ID‘);
// $session = new Session($storage);

$container[‘session‘] = $container->factory(function ($c) {
    return new Session($c[‘session_storage‘]);
});

// define some parameters
$container[‘cookie_name‘] = ‘SESSION_ID‘;
$container[‘session_storage_class‘] = ‘SessionStorage‘;

$container[‘session_storage‘] = function ($c) {
    return new $c[‘session_storage_class‘]($c[‘cookie_name‘]);
};

$container[‘random_func‘] = $container->protect(function () {
    return rand();
});

$container[‘session_storage‘] = function ($c) {
    return new $c[‘session_storage_class‘]($c[‘cookie_name‘]);
};


$container->extend(‘session_storage‘, function ($storage, $c) {
    $storage->...();
    return $storage;
});

use Pimple\Container;


class FooProvider implements Pimple\ServiceProviderInterface
{
    public function register(Container $pimple)
    {
        // register some services and parameters
        // on $pimple
    }
}

$pimple->register(new FooProvider());

$container[‘session‘] = function ($c) {
    return new Session($c[‘session_storage‘]);
};


$sessionFunction = $container->raw(‘session‘);

$app = Factory::officialAccount($config);
$app = Factory::payment($config);
$app = Factory::miniProgram($config);
$openPlatform = Factory::openPlatform($config);
$app = Factory::work($config);
$app = Factory::openWork($config);
$app = Factory::microMerchant($config);

    public static function __callStatic($name, $arguments)
    {
        return self::make($name, ...$arguments);
    }


    public static function make($name, array $config)
    {
        $namespace = Kernel\Support\Str::studly($name); //Convert a value to studly caps case.
        $application = "\\\\EasyWeChat\\{$namespace}\\Application";
        return new $application($config);
    }

protected $providers = [
        Auth\ServiceProvider::class,
        Server\ServiceProvider::class,
        User\ServiceProvider::class,
        OAuth\ServiceProvider::class,
        ……

]

class ServiceContainer extends Container
{
    use WithAggregator;//代码复用特性


    protected $id;//服务名称，这里没有用到这个变量，Provider内部都已经设置了name。
    protected $providers = [];//服务提供者变量
    protected $defaultConfig = [];//默认配置变量
    protected $userConfig = [];//用户的配置变量


    /**
     * Constructor.
     *
     * @param array $config
     * @param array $prepends
     * @param string|null $id
     */
    public function __construct(array $config = [], array $prepends = [], string $id = null)
    {
        $this->registerProviders($this->getProviders());//注册由Provider提供的服务
        parent::__construct($prepends);//默认情况下，容器可以预先传递一个对象或变量数组
        $this->userConfig = $config;//获取用户传递的配置
        $this->id = $id;//默认为null
        $this->aggregate();//WithAggregator中的方法，设置默认配置
        $this->events->dispatch(new Events\ApplicationInitialized($this));//初始化完成事件分发，这里的events也是服务，在registerProviders完成了注册，所以这里可以直接调用了。
    }


    public function getId()
    {
        return $this->id ?? $this->id = md5(json_encode($this->userConfig));//如果id为null，那么使用用户配置来MD5算出id
    }
    public function getConfig()

    {
        $base = [
            // http://docs.guzzlephp.org/en/stable/request-options.html
            ‘http‘ => [
                ‘timeout‘ => 30.0,
                ‘base_uri‘ => ‘https://api.weixin.qq.com/‘,
            ],
        ];
        return array_replace_recursive($base, $this->defaultConfig, $this->userConfig);//从后往前迭代覆盖前面相同key的数组值
    }


    /**
     * Return all providers.
     *
     * @return array
     */
    public function getProviders()
    {
        return array_merge([
            ConfigServiceProvider::class,
            LogServiceProvider::class,
            RequestServiceProvider::class,
            HttpClientServiceProvider::class,
            ExtensionServiceProvider::class,
            EventDispatcherServiceProvider::class,
        ], $this->providers);//返回合并后的Provider，这里默认有几个核心服务Provider
    }


    /**
     * @param string $id
     * @param mixed $value
     */
    public function rebind($id, $value)
    {
        $this->offsetUnset($id);//重新绑定服务
        $this->offsetSet($id, $value);
    }


    /**
     * Magic get access. 魔法函数，这样就可以以对象的形式去获取数组值了。
     * @param string $id
     * @return mixed
     */
    public function __get($id)
    {
        if ($this->shouldDelegate($id)) {
            return $this->delegateTo($id);//EasyWechat的代理方法，暂时不理。
        }


        return $this->offsetGet($id);
    }


    /**
     * Magic set access.魔法函数，这样就可以通过对象形式设置数组了
     * @param string $id
     * @param mixed $value
     */
    public function __set($id, $value)
    {
        $this->offsetSet($id, $value);
    }


    /**
     * @param array $providers
     */
    public function registerProviders(array $providers)
    {
        foreach ($providers as $provider) {
            parent::register(new $provider());//调用Container的Register方法”注册“服务，
        }
    }
}

    public function register(ServiceProviderInterface $provider, array $values = array())
    {
        $provider->register($this);//调用Provider的register函数真正的注册服务
        foreach ($values as $key => $value) {
            $this[$key] = $value;
        }
        return $this;

    }

class ServiceProvider implements ServiceProviderInterface
{
    public function register(Container $app)
    {
        $app[‘template_message‘] = function ($app) {
            return new Client($app);
        };
    }
}

    public function offsetSet($id, $value)
    {
        if (isset($this->frozen[$id])) {
            throw new FrozenServiceException($id);
        }
        $this->values[$id] = $value;//用来保存实例化匿名函数，结合上文这里$value=匿名实例化函数，$id=template_message
        $this->keys[$id] = true;//用来判断id是否存在
    }

    public function offsetGet($id)
    {
        if (!isset($this->keys[$id])) {
            throw new UnknownIdentifierException($id);//如果id不存在，说明没有赋值，报错
        }


        if (
            isset($this->raw[$id])//如果已经实例化，raw会被赋值原匿名函数
            || !\is_object($this->values[$id])//如果值不是对象
            || isset($this->protected[$this->values[$id]])//如果设置了保护变量
            || !\method_exists($this->values[$id], ‘__invoke‘)//如果不是调用的方法
        ) {
            return $this->values[$id];//那么就返回值
        }


        if (isset($this->factories[$this->values[$id]])) {//如果定义了工厂类服务
            return $this->values[$id]($this);//那么每次都返回不一样的对象（这里实时实例化）
        }


        $raw = $this->values[$id];//raw赋值为匿名函数
        $val = $this->values[$id] = $raw($this);//调用匿名函数实例化服务类
        $this->raw[$id] = $raw;//raw数组保存当前匿名函数


        $this->frozen[$id] = true;//实例化完成，冻结服务，禁止再次实例化。


        return $val;
    }