<?php
class ReutersBridge extends BridgeAbstract
{
	const MAINTAINER = 'hollowleviathan, spraynard, csisoap';
	const NAME = 'Reuters Bridge';
	const URI = 'https://www.reuters.com';
	const CACHE_TIMEOUT = 1800; // 30min
	const DESCRIPTION = 'Returns news from Reuters';

	private $feedName = self::NAME;
	private $useWireAPI = false;

	/**
	 * Wireitem types allowed in the final story output
	 */
	const ALLOWED_WIREITEM_TYPES = array(
		'story',
		'headlines'
	);

	/**
	 * Wireitem template types allowed in the final story output
	 */
	const ALLOWED_TEMPLATE_TYPES = array(
		'story',
		'headlines'
	);

	const PARAMETERS = array(
		array(
			'feed' => array(
				'name' => 'News Feed',
				'type' => 'list',
				'title' => 'Feeds from Reuters U.S/International edition',
				'values' => array(
					'Top News' => 'home/topnews',
					'Fact Check' => 'chan:abtpk0vm',
					'Entertainment' => 'chan:8ym8q8dl',
					'Politics' => 'politics',
					'Wire' => 'wire',
					'Breakingviews' => '/breakingviews',
					'World' => array(
						'World' => 'world',
						'Africa' => '/world/africa',
						'Americas' => '/world/americas',
						'Asia-Pacific' => '/world/asia-pacific',
						'China' => 'china',
						'europe' => '/world/europe',
						'India' => '/world/india',
						'Middle East' => '/world/middle-east',
						'UK' => 'chan:61leiu7j',
						'USA News' => 'us',
						'The Great Reboot' => '/world/the-great-reboot',
						'Reuters Next' => '/world/reuters-next'
					),
					'Business' => array(
						'Business' => 'business',
						'Aerospace and Defense' => 'aerospace',
						'Autos Transportation' => '/business/autos-transportation',
						'Energy' => 'energy',
						'Finance' => '/business/finance',
						'Health' => 'chan:8hw7807a',
						'Media Telecom' => '/business/media-telecom',
						'Retail Consumer' => '/business/retail-consumer',
						'Sustainable Business' => '/business/sustainable-business',
						'Change Suite' => '/business/change-suite',
						'Future of Health' => '/business/future-of-health',
						'Future of Money' => '/business/future-of-money',
						'Take Five' => '/business/take-five',
						'Reuters Impact' => '/business/reuters-impact',
					),
					'Legal' => array(
						'Legal' => '/legal',
						'Government' => '/legal/government',
						'Legal Industry' => '/legal/legalindustry',
						'Litigation' => '/legal/litigation',
						'Transactional' => '/legal/transactional',
					),
					'Markets' => array(
						'Markets' => 'markets',
						'Asian Markets' => '/markets/asia',
						'Commodities' => '/markets/commodities',
						'Currencies' => '/markets/currencies',
						'Deals' => '/markets/deals',
						'European Markets' => '/markets/europe',
						'Funds' => '/markets/fund',
						'Global Market Data' => '/markets/global-market-data',
						'Rates & Bonds' => '/markets/rates-bonds',
						'Stocks' => '/markets/stocks',
						'U.S Markets' => '/markets/us',
						'Wealth' => '/markets/wealth',
						'Macro Matters' => '/markets/macromatters',
					),
					'Technology' => array(
						'Technology' => 'tech',
						'Disrupted' => '/technology/disrupted',
						'Reuters Momentum' => '/technology/reuters-momentum',
					),
					'Sports' => array(
						'Sports' => 'sports',
						'Athletics' => '/lifestyle/sports/athletics',
						'Cricket' => '/lifestyle/sports/cricket',
						'Cycling' => '/lifestyle/sports/cycling',
						'Golf' => '/lifestyle/sports/golf',
						'Motor Sports' => '/lifestyle/sports/motor-sports',
						'Soccer' => '/lifestyle/sports/soccer',
						'Tennis' => '/lifestyle/sports/tennis',
					),
					'Lifestyle' => array(
						'Lifestyle' => 'life',
						'Oddly Enough' => '/lifestyle/oddly-enough',
						'Science' => 'science',
					)
				)
			)
		)
	);

	const BACKWARD_COMPATIBILITY = array(
		'world' => '/world',
		'china' => '/world/china',
		'chan:61leiu7j' => '/world/uk',
		'us' => '/world/us',
		'business' => '/business',
		'aerospace' => '/business/aerospace-defense',
		'energy' => '/business/energy',
		'environment' => '/business/environment',
		'chan:8hw7807a' => '/business/healthcare-pharmaceuticals',
		'markets' => '/markets',
		'tech' => '/technology',
		'sports' => '/lifestyle/sports',
		'life' => '/lifestyle',
		'science' => '/lifestyle/science',
	);

	const OLD_WIRE_SECTION = array(
		'home/topnews',
		'chan:abtpk0vm',
		'chan:8ym8q8dl',
		'politics',
		'wire'
	);

	/**
	 * Performs an HTTP request to the Reuters API and returns decoded JSON
	 * in the form of an associative array
	 * @param string $feed_uri Full API URL to fetch data
	 * @return array
	 */
	private function getJson($uri)
	{
		$returned_data = getContents($uri);
		return json_decode($returned_data, true);
	}

	/**
	 * Takes in data from Reuters Wire API and
	 * creates structured data in the form of a list
	 * of story information.
	 * @param array $data JSON collected from the Reuters Wire API
	 */
	private function processData($data)
	{
		/**
		 * Gets a list of wire items which are groups of templates
		 */
		$reuters_allowed_wireitems = array_filter(
			$data, function ($wireitem) {
				return in_array(
					$wireitem['wireitem_type'],
					self::ALLOWED_WIREITEM_TYPES
				);
			}
		);

		/*
		* Gets a list of "Templates", which is data containing a story
		*/
		$reuters_wireitem_templates = array_reduce(
			$reuters_allowed_wireitems,
			function (array $carry, array $wireitem) {
				$wireitem_templates = $wireitem['templates'];
				return array_merge(
					$carry,
					array_filter(
						$wireitem_templates, function (
							array $template_data
						) {
							return in_array(
								$template_data['type'],
								self::ALLOWED_TEMPLATE_TYPES
							);
						}
					)
				);
			},
			array()
		);

		return $reuters_wireitem_templates;
	}

	private function getSectionEndpoint() {
		$endpoint = $this->getInput('feed');
		if(isset(self::BACKWARD_COMPATIBILITY[$endpoint])) {
			$endpoint = self::BACKWARD_COMPATIBILITY[$endpoint];
		} elseif (in_array($endpoint, self::OLD_WIRE_SECTION)) {
			$this->useWireAPI = true;
		}
		return $endpoint;
	}

	/**
	* @param string $endpoint - Provide section's endpoint to Reuters API.
	* @param string $fetch_type - Provide what kind of fetch do you want? Article or Section.
	* @return string A completed API URL to fetch data
	*/
	private function getAPIURL($endpoint, $fetch_type) {
		$base_url = self::URI . '/pf/api/v3/content/fetch/';
		$wire_url = 'https://wireapi.reuters.com/v8';
		switch($fetch_type) {
			case 'article':
				if($this->useWireAPI) {
					return $wire_url . $endpoint;
				}
				$query = array(
					'website_url' => $endpoint,
					'website' => 'reuters'
				);
				$json_query = json_encode($query);
				return $base_url . 'article-by-id-or-url-v1?query=' . $json_query;
				break;
			case 'section':
				if($this->useWireAPI) {
					if(strpos($endpoint, 'chan:') !== false) {
					// Now checking whether that feed has unique ID or not.
						$feed_uri = "/feed/rapp/us/wirefeed/$endpoint";
					} else {
						$feed_uri = "/feed/rapp/us/tabbar/feeds/$endpoint";
					}
					return $wire_url . $feed_uri;
				}
				$query = array(
					'fetch_type' => 'section',
					'section_id' => $endpoint,
					'size' => 30,
					'website' => 'reuters'
				);
				$json_query = json_encode($query);
				return $base_url . 'articles-by-section-alias-or-id-v1?query=' . $json_query;
				break;
		}
		returnServerError('unsupported endpoint');
	}

	private function getArticle($feed_uri)
	{
		// This will make another request to API to get full detail of article and author's name.
		$url = $this->getAPIURL($feed_uri, 'article');
		$rawData = $this->getJson($url);
		$article_content = '';
		$authorlist = '';
		$category = array();
		$image_list = array();
		$published_at = '';
		if($this->useWireAPI) {
			$reuters_wireitems = $rawData['wireitems'];
			$processedData = $this->processData($reuters_wireitems);

			$first = reset($processedData);
			$article_content = $first['story']['body_items'];
			$authorlist = $first['story']['authors'];
			$category = array($first['story']['channel']['name']);
			$image_list = $first['story']['images'];
			$published_at = $first['story']['published_at'];
		} else {
			$article_content = $rawData['result']['content_elements'];
			$authorlist = $rawData['result']['authors'];
			$category = array($rawData['result']['taxonomy']['ads_primary_section']['name']);
			$image_list = array();
			if(!empty($rawData['result']['related_content']['galleries'])) {
				$galleries = $rawData['result']['related_content']['galleries'];
				foreach($galleries as $gallery) {
					$image_list = array_merge($image_list, $gallery['content_elements']);
				}
			} else if(!empty($rawData['result']['related_content']['images'])) {
				$image_list = $rawData['result']['related_content']['images'];
			}
			$published_at = $rawData['result']['published_time'];
		}

		$content_detail = array(
			'content' => $this->handleArticleContent($article_content),
			'author' => $this->handleAuthorName($authorlist),
			'category' => $category,
			'images' => $this->handleImage($image_list),
			'published_at' => $published_at
		);
		return $content_detail;
	}

	private function handleImage($images) {
		$img_placeholder = '';

		foreach($images as $image) { // Add more image to article.
			$image_url = $image['url'];
			$image_caption = $image['caption'];
			$image_alt_text = '';
			if(isset($image['alt_text'])) {
				$image_alt_text = $image['alt_text'];
			} else {
				$image_alt_text = $image_caption;
			}
			$img = "<img src=\"$image_url\" alt=\"$image_alt_text\">";
			$img_caption = "<figcaption style=\"text-align: center;\"><i>$image_caption</i></figcaption>";
			$figure = "<figure>$img \t $img_caption</figure>";
			$img_placeholder = $img_placeholder . $figure;
		}

		return $img_placeholder;
	}

	private function handleAuthorName($authors) {
		$author = '';
		$counter = 0;
		foreach ($authors as $data) {
			//Formatting author's name.
			$name = $data['name'];
			$counter++;
			if($counter == count($authors)) {
				$author .= $name;
			} else {
				$author .= $name . ', ';
			}
		}
		return $author;
	}

	private function handleArticleContent($contents) {
		$description = '';
		foreach ($contents as $content) {
			$data;
			if(isset($content['content'])) {
				$data = $content['content'];
			}
			switch($content['type']) {
				case 'paragraph':
					$description = $description . "<p>$data</p>";
					break;
				case 'heading':
					$description = $description . "<h3>$data</h3>";
					break;
				case 'infographics':
					$description = $description . "<img src=\"$data\">";
					break;
				case 'inline_items':
					$item_list = $content['items'];
					$description = $description . '<p>';
					foreach ($item_list as $item) {
						if($item['type'] == 'text') {
							$description = $description . $item['content'];
						} else {
							$description = $description . $item['symbol'];
						}
					}
					$description = $description . '</p>';
					break;
				case 'p_table':
					$description = $description . $content['content'];
					break;
				case 'upstream_embed':
					$media_type = $content['media_type'];
					$cid = $content['cid'];
					$embed = '';
					switch ($media_type) {
						case 'tweet':
							try {
								$tweet_url = "https://twitter.com/dummyname/statuses/$cid";
								$get_embed_url = 'https://publish.twitter.com/oembed?url='
																 . urlencode($tweet_url) .
																'&partner=&hide_thread=false';
								$oembed_json = json_decode(getContents($get_embed_url), true);
								$embed .= $oembed_json['html'];
							} catch (Exception $e) { // In case not found any tweet.
								$embed .= '';
							}
							break;
						case 'instagram':
							$url = "https://instagram.com/p/$cid/media/?size=l";
							$embed .= <<<EOD
<img 
	src="{$url}"
	alt="instagram-image-$cid"
>
EOD;
							break;
						case 'youtube':
							$url = "https://www.youtube.com/embed/$cid";
							$embed .= <<<EOD
<‌iframe
	width="560" 
	height="315" 
	src="{$url}"
	frameborder="0" 
	allowfullscreen
>
</iframe>
EOD;
							break;
					}
					$description .= $embed;
					break;
				case 'social_media':
					if ($content['sub_type'] == 'twitter') {
						$description .= $content['html'];
					}
					break;
				case 'table':
					$table = '<table>';
					$theaders = $content['header'];
					$tr = '<tr>';
					foreach($theaders as $header) {
						$tr .= '<th>' . $header . '</th>';
					}
					$tr .= '</tr>';
					$table .= $tr;
					$rows = $content['rows'];
					foreach($rows as $row) {
						$tr = '<tr>';
						foreach($row as $data) {
							$tr .= '<td>' . $data . '</td>';
						}
						$tr .= '</tr>';
						$table .= $tr;
					}
					$table .= '</table>';
					$description .= $table;
					break;
				case 'image':
					$description .= $this->handleImage(array($content));
			}
		}

		return $description;
	}

	public function getName() {
		return $this->feedName;
	}

	public function collectData()
	{
		$endpoint = $this->getSectionEndpoint();
		$url = $this->getAPIURL($endpoint, 'section');
		$data = $this->getJson($url);

		$stories = array();
		$section_name = '';
		if($this->useWireAPI) {
			$reuters_wireitems = $data['wireitems'];
			$section_name = $data['wire_name'];
			$processedData = $this->processData($reuters_wireitems);

			// Merge all articles from Editor's Highlight section into existing array of templates.
			$top_section = reset($processedData);
			if ($top_section['type'] == 'headlines') {
				$top_section = array_shift($processedData);
				$articles = $top_section['headlines'];
				$processedData = array_merge($articles, $processedData);
			}
			$stories = $processedData;
		} else {
			$section_name = $data['result']['section']['name'];
			if(isset($data['arcResult']['articles'])) {
				$stories = $data['arcResult']['articles'];
			} else {
				$stories = $data['result']['articles'];
			}
		}
		$this->feedName = $section_name . ' | Reuters';

		foreach ($stories as $story) {
			$uid = '';
			$author = '';
			$category = array();
			$content = '';
			$title = '';
			$timestamp = '';
			$url = '';
			$article_uri = '';
			$source_type = '';
			if($this->useWireAPI) {
				$uid = $story['story']['usn'];
				$article_uri = $story['template_action']['api_path'];
				$title = $story['story']['hed'];
				$url = $story['template_action']['url'];
			} else {
				$uid = $story['id'];
				$url = self::URI . $story['canonical_url'];
				$title = $story['title'];
				$article_uri = $story['canonical_url'];
				$source_type = $story['source']['name'];
			}

			// Some article cause unexpected behaviour like redirect to another site not API.
			// Attempt to check article source type to avoid this.
			if($source_type == 'composer') { // Only Reuters PF api have this, Wire don't.
				$author = $this->handleAuthorName($story['authors']);
				$timestamp = $story['published_time'];
				$image_placeholder = '';
				if (isset($story['thumbnail'])) {
					$image_placeholder = $this->handleImage(array($story['thumbnail']));
				}
				$content = $story['description'] . $image_placeholder;
			} else {
				$content_detail = $this->getArticle($article_uri);
				$description = $content_detail['content'];
				$description = defaultLinkTo($description, $this->getURI());

				$author = $content_detail['author'];
				$images = $content_detail['images'];
				$category = $content_detail['category'];
				$content = "$description  $images";
				$timestamp = $content_detail['published_at'];
			}

			$item['categories'] = $category;
			$item['author'] = $author;
			$item['content'] = $content;
			$item['title'] = $title;
			$item['timestamp'] = $timestamp;
			$item['uri'] = $url;
			$this->items[] = $item;
		}
	}
}