<?php
class InstagramBridge extends BridgeAbstract {

	const MAINTAINER = 'pauder';
	const NAME = 'Instagram Bridge';
	const URI = 'https://www.instagram.com/';
	const DESCRIPTION = 'Returns the newest images';

	const PARAMETERS = array(
		'Username' => array(
			'u' => array(
				'name' => 'username',
				'required' => true
			)
		),
		'Hashtag' => array(
			'h' => array(
				'name' => 'hashtag',
				'required' => true
			)
		),
		'Location' => array(
			'l' => array(
				'name' => 'location',
				'required' => true
			)
		),
		'global' => array(
			'media_type' => array(
				'name' => 'Media type',
				'type' => 'list',
				'required' => false,
				'values' => array(
					'All' => 'all',
					'Story' => 'story',
					'Video' => 'video',
					'Picture' => 'picture',
				),
				'defaultValue' => 'all'
			)
		)

	);

	const USER_QUERY_HASH = '58b6785bea111c67129decbe6a448951';
	const TAG_QUERY_HASH = '174a5243287c5f3a7de741089750ab3b';
	const STORY_QUERY_HASH = '865589822932d1b43dfe312121dd353a';

	protected function getInstagramUserId($username) {

		if(is_numeric($username)) return $username;

		$cacheFac = new CacheFactory();
		$cacheFac->setWorkingDir(PATH_LIB_CACHES);
		$cache = $cacheFac->create(Configuration::getConfig('cache', 'type'));
		$cache->setScope(get_called_class());
		$cache->setKey([$username]);
		$key = $cache->loadData();

		if($key == null) {
				$data = getContents(self::URI . 'web/search/topsearch/?query=' . $username);

				foreach(json_decode($data)->users as $user) {
					if($user->user->username === $username) {
						$key = $user->user->pk;
					}
				}
				if($key == null) {
					returnServerError('Unable to find username in search result.');
				}
				$cache->saveData($key);
		}
		return $key;

	}

	public function collectData(){

		if(is_null($this->getInput('u')) && $this->getInput('media_type') == 'story') {
			returnClientError('Stories are not supported for hashtags nor locations!');
		}

		$data = $this->getInstagramJSON($this->getURI());

		if(!is_null($this->getInput('u'))) {
			$userMedia = $data->data->user->edge_owner_to_timeline_media->edges;
		} elseif(!is_null($this->getInput('h'))) {
			$userMedia = $data->data->hashtag->edge_hashtag_to_media->edges;
		} elseif(!is_null($this->getInput('l'))) {
			$userMedia = $data->entry_data->LocationsPage[0]->graphql->location->edge_location_to_media->edges;
		}

		foreach($userMedia as $media) {
			$media = $media->node;

			if(!is_null($this->getInput('u'))) {
				switch($this->getInput('media_type')) {
					case 'all': break;
					case 'video':
						if($media->__typename != 'GraphVideo') continue 2;
						break;
					case 'picture':
						if($media->__typename != 'GraphImage') continue 2;
						break;
					case 'story':
						if($media->__typename != 'GraphSidecar') continue 2;
						break;
					default: break;
				}
			} else {
				if($this->getInput('media_type') == 'video' && !$media->is_video) continue;
			}

			$item = array();
			$item['uri'] = self::URI . 'p/' . $media->shortcode . '/';

			if (isset($media->owner->username)) {
				$item['author'] = $media->owner->username;
			}

			if (isset($media->edge_media_to_caption->edges[0]->node->text)) {
				$textContent = $media->edge_media_to_caption->edges[0]->node->text;
			} else {
				$textContent = '(no text)';
			}

			$item['title'] = ($media->is_video ? '▶ ' : '') . trim($textContent);
			$titleLinePos = strpos(wordwrap($item['title'], 120), "\n");
			if ($titleLinePos != false) {
				$item['title'] = substr($item['title'], 0, $titleLinePos) . '...';
			}

			if(!is_null($this->getInput('u')) && $media->__typename == 'GraphSidecar') {

				$data = $this->getInstagramStory($item['uri']);
				$item['content'] = $data[0];
				$item['enclosures'] = $data[1];
			} else {
				$mediaURI = self::URI . 'p/' . $media->shortcode . '/media?size=l';
				$item['content'] = '<a href="' . htmlentities($item['uri']) . '" target="_blank">';
				$item['content'] .= '<img src="' . htmlentities($mediaURI) . '" alt="' . $item['title'] . '" />';
				$item['content'] .= '</a><br><br>' . nl2br(htmlentities($textContent));
				$item['enclosures'] = array($mediaURI);
			}

			$item['timestamp'] = $media->taken_at_timestamp;

			$this->items[] = $item;
		}
	}

	protected function getInstagramStory($uri) {

		$shortcode = explode('/', $uri)[4];
		$data = getContents(self::URI .
					'graphql/query/?query_hash=' .
					 self::STORY_QUERY_HASH .
					 '&variables={"shortcode"%3A"' .
					$shortcode .
					'"}');

		$mediaInfo = json_decode($data)->data->shortcode_media;

		//Process the first element, that isn't in the node graph
		if (count($mediaInfo->edge_media_to_caption->edges) > 0) {
			$caption = $mediaInfo->edge_media_to_caption->edges[0]->node->text;
		} else {
			$caption = '';
		}

		$enclosures = [$mediaInfo->display_url];
		$content = '<img src="' . htmlentities($mediaInfo->display_url) . '" alt="' . $caption . '" />';

		foreach($mediaInfo->edge_sidecar_to_children->edges as $media) {
			$display_url = $media->node->display_url;
			if(!in_array($display_url, $enclosures)) { // add only if not added yet
				$content .= '<img src="' . htmlentities($display_url) . '" alt="' . $caption . '" />';
				$enclosures[] = $display_url;
			}
		}

		return [$content, $enclosures];

	}

	protected function getInstagramJSON($uri) {

		if(!is_null($this->getInput('u'))) {

			$userId = $this->getInstagramUserId($this->getInput('u'));

			$data = getContents(self::URI .
								'graphql/query/?query_hash=' .
								 self::USER_QUERY_HASH .
								 '&variables={"id"%3A"' .
								$userId .
								'"%2C"first"%3A10}');
			return json_decode($data);

		} elseif(!is_null($this->getInput('h'))) {
			$data = getContents(self::URI .
					'graphql/query/?query_hash=' .
					 self::TAG_QUERY_HASH .
					 '&variables={"tag_name"%3A"' .
					$this->getInput('h') .
					'"%2C"first"%3A10}');
			return json_decode($data);

		} else {

			$html = getContents($uri)
				or returnServerError('Could not request Instagram.');
			$scriptRegex = '/window\._sharedData = (.*);<\/script>/';

			preg_match($scriptRegex, $html, $matches, PREG_OFFSET_CAPTURE, 0);

			return json_decode($matches[1][0]);

		}

	}

	public function getName(){
		if(!is_null($this->getInput('u'))) {
			return $this->getInput('u') . ' - Instagram Bridge';
		}

		return parent::getName();
	}

	public function getURI(){
		if(!is_null($this->getInput('u'))) {
			return self::URI . urlencode($this->getInput('u')) . '/';
		} elseif(!is_null($this->getInput('h'))) {
			return self::URI . 'explore/tags/' . urlencode($this->getInput('h'));
		} elseif(!is_null($this->getInput('l'))) {
			return self::URI . 'explore/locations/' . urlencode($this->getInput('l'));
		}
		return parent::getURI();
	}
}