<?php
/**
*
* This file is part of the phpBB Forum Software package.
*
* @copyright (c) phpBB Limited <https://www.phpbb.com>
* @license GNU General Public License, version 2 (GPL-2.0)
*
* For full copyright and license information, please see
* the docs/CREDITS.txt file.
*
*/

namespace phpbb\notification\method;

use phpbb\config\config;
use phpbb\db\driver\driver_interface;
use phpbb\json\sanitizer;
use phpbb\notification\type\type_interface;
use phpbb\user;
use phpbb\user_loader;

/**
* Web push notification method class
* This class handles sending push messages for notifications
*/

class webpush extends \phpbb\notification\method\messenger_base
{
	/** @var config */
	protected $config;

	/** @var driver_interface */
	protected $db;

	/** @var user */
	protected $user;

	/** @var string Notification web push table */
	protected $notification_webpush_table;

	/**
	 * Notification Method web push constructor
	 *
	 * @param user_loader $user_loader
	 * @param user $user
	 * @param config $config
	 * @param driver_interface $db
	 * @param string $phpbb_root_path
	 * @param string $php_ext
	 * @param string $notification_webpush_table
	 */
	public function __construct(user_loader $user_loader, user $user, config $config, driver_interface $db, string $phpbb_root_path, string $php_ext, string $notification_webpush_table)
	{
		parent::__construct($user_loader, $phpbb_root_path, $php_ext);

		$this->user = $user;
		$this->config = $config;
		$this->db = $db;
		$this->notification_webpush_table = $notification_webpush_table;
	}

	/**
	* {@inheritDoc}
	*/
	public function get_type(): string
	{
		return 'notification.method.webpush';
	}

	/**
	* {@inheritDoc}
	*/
	public function is_available(type_interface $notification_type = null): bool
	{
		return parent::is_available($notification_type) && $this->config['webpush_enable']
			&& !empty($this->config['webpush_vapid_public']) && !empty($this->config['webpush_vapid_private']);
	}

	/**
	* {@inheritdoc}
	*/
	public function get_notified_users($notification_type_id, array $options): array
	{
		$notified_users = [];

		$sql = 'SELECT user_id
			FROM ' . $this->notification_webpush_table . '
			WHERE notification_type_id = ' . (int) $notification_type_id .
			(isset($options['item_id']) ? ' AND item_id = ' . (int) $options['item_id'] : '') .
			(isset($options['item_parent_id']) ? ' AND item_parent_id = ' . (int) $options['item_parent_id'] : '') .
			(isset($options['user_id']) ? ' AND user_id = ' . (int) $options['user_id'] : '');
		$result = $this->db->sql_query($sql);
		while ($row = $this->db->sql_fetchrow($result))
		{
			$notified_users[$row['user_id']] = $row;
		}
		$this->db->sql_freeresult($result);

		return $notified_users;
	}

	/**
	* Parse the queue and notify the users
	*/
	public function notify()
	{
		$insert_buffer = new \phpbb\db\sql_insert_buffer($this->db, $this->notification_webpush_table);

		/** @var type_interface $notification */
		foreach ($this->queue as $notification)
		{
			$data = self::clean_data($notification->get_insert_array());
			$insert_buffer->insert($data);
		}

		$insert_buffer->flush();

		$this->notify_using_webpush();

		return false;
	}

	/**
	 * Notify using web push
	 *
	 * @return void
	 */
	protected function notify_using_webpush(): void
	{
		if (empty($this->queue))
		{
			return;
		}

		// Load all users we want to notify (we need their email address)
		$user_ids = [];
		foreach ($this->queue as $notification)
		{
			$user_ids[] = $notification->user_id;
		}

		// We do not send emails to banned users
		if (!function_exists('phpbb_get_banned_user_ids'))
		{
			include($this->phpbb_root_path . 'includes/functions_user.' . $this->php_ext);
		}
		$banned_users = phpbb_get_banned_user_ids($user_ids);

		// Load all the users we need
		$this->user_loader->load_users(array_diff($user_ids, $banned_users), array(USER_IGNORE));

		$web_push = new \Minishlink\WebPush\WebPush();

		// Time to go through the queue and send emails
		/** @var type_interface $notification */
		foreach ($this->queue as $notification)
		{
			$user = $this->user_loader->get_user($notification->user_id);

			$user_subscriptions = sanitizer::decode($this->user->data['user_push_subscriptions']);

			if ($user['user_type'] == USER_INACTIVE && $user['user_inactive_reason'] == INACTIVE_MANUAL
				|| empty($user_subscriptions))
			{
				continue;
			}

			// add actual web push data
			$data['data'] = [
				'body'		=> $notification->get_title(),
				'icon'		=> '', // @todo: to be filled?
				'image'		=> '', // @todo: to be filled?
				'title'		=> $this->config['sitename'],
				'url'		=> $notification->get_url(),
				'user_id'	=> $notification->user_id,
			];
			$json_data = json_encode($data);

			// @todo: start implementing actual web push code

			foreach ($user_subscriptions as $subscription)
			{
				try
				{
					$push_subscription = \Minishlink\WebPush\Subscription::create($subscription);
					$web_push->queueNotification($push_subscription, $json_data);
				}
				catch (\ErrorException $exception)
				{
					// @todo: decide whether we want to remove invalid subscriptions directly?
					// Might need too many resources ...
				}
			}
		}

		// @todo: Try offloading to after request
		try
		{
			$web_push->flush();
		}
		catch (\ErrorException $exception)
		{
			// @todo: Add to error log if we can't flush ...
		}

		// We're done, empty the queue
		$this->empty_queue();
	}

	/**
	* {@inheritdoc}
	*/
	public function mark_notifications($notification_type_id, $item_id, $user_id, $time = false, $mark_read = true)
	{
		$sql = 'DELETE FROM ' . $this->notification_webpush_table . '
			WHERE ' . ($notification_type_id !== false ? $this->db->sql_in_set('notification_type_id', $notification_type_id) : '1=1') .
			($user_id !== false ? ' AND ' . $this->db->sql_in_set('user_id', $user_id) : '') .
			($item_id !== false ? ' AND ' . $this->db->sql_in_set('item_id', $item_id) : '');
		$this->db->sql_query($sql);
	}

	/**
	* {@inheritdoc}
	*/
	public function mark_notifications_by_parent($notification_type_id, $item_parent_id, $user_id, $time = false, $mark_read = true)
	{
		$sql = 'DELETE FROM ' . $this->notification_webpush_table . '
			WHERE ' . ($notification_type_id !== false ? $this->db->sql_in_set('notification_type_id', $notification_type_id) : '1=1') .
			($user_id !== false ? ' AND ' . $this->db->sql_in_set('user_id', $user_id) : '') .
			($item_parent_id !== false ? ' AND ' . $this->db->sql_in_set('item_parent_id', $item_parent_id, false, true) : '');
		$this->db->sql_query($sql);
	}

	/**
	 * Clean data to contain only what we need for webpush notifications table
	 *
	 * @param array $data Notification data
	 * @return array Cleaned notification data
	 */
	public static function clean_data(array $data)
	{
		$row = [
			'notification_type_id'	=> null,
			'item_id'				=> null,
			'item_parent_id'		=> null,
			'user_id'				=> null,
		];

		return array_intersect_key($data, $row);
	}
}