news_source_manager = $news_source_manager;
$this->news_parser = $news_parser;
}

/**
* @param array $sources
* @return mixed
*/
public function get_news(array $sources): array
{
$news = [];
/**
* @var news_source_interface $source
*/
foreach ($sources as $source)
{
$news_from_source = $this->get_news_from_source($source);
$news = array_merge($news, $news_from_source);
}

return $news;
}

/**
* @param news_source_interface $source
* @return array
*/
public function get_news_from_source(news_source_interface $source): array
{
$source_content = $source->get_news_content();
$parsed_news = $this->news_parser->parse($source_content);

return $parsed_news;
}

/**
* @param $source_name
* @return news_source_interface
*/
public function get_news_source($source_name): news_source_interface
{
return $this->news_source_manager->get_source($source_name);
}
}