Elkarte Hashtags

Controller.Hashtags.php

<?php

namespace Hashtags\Controller;

class Hashtags
{
	protected $hashtag_manager;

	public function pre_dispatch()
	{
		loadTemplate('Hashtags');
		loadLanguage('Hashtags');
	}

	public function action_search()
	{
		// Get the tag
		$tag = $this->getTag();

		// We have a tag! Time to search for it
		if (!empty($tag))
		{
			$this->results($tag);
		}

		// Should we get the trends here?
	}

	public function results($tag)
	{
		require_once(SUBS_DIR . '/Boards.subs.php');
		$accessible_boards = accessibleBoards();
		// if empty($accessible_boards), exit with "no messages" error

		$msg_ids = $this->hashtag_manager->getMessageIdsByTag($tag, $accessible_boards, $start, $limit);
		$messages = [];
		foreach ($msg_ids as $id)
		{
			$messages[] = basicMessageInfo($id, true);
		}
	}

	public function action_cleanOldTags()
	{
		// if request == POST ? $hashtag_manager->removeOldTags();
		$GLOBALS['context']['sub_template'] = 'cleanOld';
	}

	public function getTag()
	{
		if (!empty($_REQUEST['tag']) && $this->hashtag_manager->isTag($_REQUEST['tag']))
		{
			// Sanitize?
			$tag = $_REQUEST['tag'];
		}
		else
		{
			$tag = '';
		}

		return $tag;
	}
}

Model.HashtagsManager.php

<?php

namespace Hashtags\Model;

class HashtagsManager
{
	protected $db;

	public function __construct($db)
	{
		$this->db = $db;
	}

	public function getTagsFromString($string)
	{
		// Must be preceeded by whitespace or start of the string
		// Must start with #
		// Ends with any non-alphanumeric character except dash or underscore

		return $tags;
	}

	public function getMessageIdsByTag($tag, array $accessible_boards, \DateTime $start, $limit = 20, $order_dir = null)
	{
		// Need to check to see if the user can see the message

		/*
		 * SELECT id_msg
		 * FROM tags AS t
		 * INNER JOIN tag_messages AS tp USING (id_tag)
		 * INNER JOIN messages AS m USING(id_msg)
		 * INNER JOIN topics AS t USING(id_topic)
		 * WHERE t.tag = $tag
		 *	AND tp.tag_dtg >= $start
		 *	AND m.approved = 1
		 *	AND t.id_board IN($accessible_boards)
		 * $order_dir === null ? '' : "ORDER BY id_msg $order_dir"
		 * LIMIT $limit
		 */

		return $ids;
	}

	public function addTag($tag, $msg_id)
	{
		/*
		 * INSERT IGNORE INTO tags
		 * 'tag' = $tag
		 * 
		 * $tag_id = LAST_INSERT_ID()
		 */

		return $tag_id;
	}

	public function getTagIds(array $tags)
	{
		/*
		 * SELECT tag_id
		 * FROM tags
		 * WHERE tag IN ($tags)
		 */
	}

	public function addTagsToMessage(array $tags, $msg_id, $is_edit = false)
	{
		$insert = $is_edit ? 'REPLACE' : 'INSERT';

		$rows = [];
		foreach ($tags as $tag)
		{
			$rows[] = [
				'tag' => $tag,
				'msg_id' => $msg_id,
				'tag_dtg' => 'NOW()'
			];
		}

		/*
		 * $insert INTO tag_messages
		 * tag = $tag,
		 * msg_id = $msg_id
		 * tag_dtg = NOW()
		 */
	}

	/**
	 * Check if a string matches the tag pattern
	 * @param string $tag
	 * @return bool
	 */
	public function isTag($tag)
	{
		
	}

	public function parseHashtagsInPost($msg_id, $string, $old_string = null)
	{
		$tags = $this->getTagsFromString($string);

		// Old string means it's an edit.
		if ($old_string !== null)
		{
			$old_tags = $this->getTagsFromString($old_string);

			// Nothing to do if nothing changed
			if ($old_tags === $tags)
			{
				return;
			}

			$tags_diff = array_diff($old_tags, $tags);
			if (!empty($tags_diff))
			{
				$this->removeTags($tags_diff);
			}
		}

		$this->addTagsToMessage($tags, $msg_id);
	}

	public function removeTags($msg_id, array $tags)
	{
		// Delete them from the post
		/*
		 * DELETE FROM tag_posts
		 * WHERE id_tag IN($tags)
		 *	AND msg_id = $msg_id
		 */

		// If there are no posts with this tag, just delete the tag
		// Maybe we shouldn't do this? Just run it as a cleanup process
		// The tags will most likely be used at other times
		// Maybe a scheduled task once a month?
		$this->removeOldTags();
	}

	public function removeOldTags()
	{
		/*
		 * DELETE FROM tags
		 * WHERE id_tag IN(
		 *	SELECT id_tag
		 *	FROM tags
		 *	LEFT JOIN tag_posts USING(id_tag)
		 *	WHERE msg_id IS NULL
		 * )
		 */
	}
}

Model.Trends.php

<?php

namespace Hashtags\Model;

class Trends
{
	public function trending($min_tag_count = 100, $num_tags = 5, $num_hours = null)
	{
		// Get the number of hours
		$num_hours = $num_hours ?: $this->getNumHoursToStartTrend($min_tag_count);

		$tags = $this->getTagsByCountAndTime($num_hours);

		// Get the first $num_tags
		return array_slice($tags, 0, $num_tags);
	}

	protected function getNumHoursToStartTrend($min_tag_count = 100)
	{
		$hours = [];
		do
		{
			$hours += $this->getNumTagsByHour();

			// Add a day to the start date.
			
		}while (count($hours) < $min_tag_count);

		return $num_hours;
	}

	protected function getNumTagsByHour(\DateTime $start_date = 'NOW()', $num_hours = 24)
	{
		/*
		 * Group the number of tags by hour:
		 * 
		 * SELECT HOUR(tag_dtg) AS tag_hour, COUNT(*) as hour_count
		 * FROM post_tags
		 * WHERE tag_dtg >= $start_date - $num_hours HOURS
		 * GROUP BY HOUR(tag_dtg)
		 * ORDER BY tag_hour
		 */

		return $hours;
	}

	protected function getTagsByCountAndTime($hours_from_now)
	{
		/*
		 * Get all of the tags in this timeframe
		 * 
		 * SELECT tag, COUNT(*) as tag_count
		 * FROM post_tags
		 * INNER JOIN tags USING(id_tag)
		 * WHERE tag_dtg >= NOW() - $hours_from_now HOURS
		 * GROUP BY id_tag
		 * ORDER BY tag_count
		 */

		return $tags;
	}
}