<?php

/*
* The cache helper is used by the protected link page when the 'multiple links' option is enabled.
* It handles reading and writing to the cache the data object which stores the number of remaining links and the remaining time a user has after solving a captcha
* data['links'] is the number of remaining links, while data['time'] is a UNIX timestamp containing the time at which the duration of the object expires
*/

namespace pedodev\linkprotection\core;

use phpbb\cache\driver\driver_interface;
use phpbb\user;
use phpbb\config\config;

class cache_helper
{
	private string $name;
	private array $data;

	public function __construct(
		private driver_interface $cache,
		private user $user,
		private config $config,
	) {}

	private function write_object(int $time): void
	{
		$this->cache->put(
			$this->name,
			$this->data,
			$time,
		);
	}

	/*
	* Read from the cache and store it in $this->data
	*/
	public function read_object(): void
	{
		if (!$this->config['pedodev_linkprotection_multiplelinks'])
		{
			return;
		}

		$this->name = 'linkprotection_' . $this->user->data['user_id'];
		$this->data = array();

		if ($this->cache->_exists($this->name))
		{
			$this->data = $this->cache->get($this->name);
		}
	}

	/*
	* Called when a user solves a captcha. Stores the number of links (depends on their group) and the duration in the cache
	*/
	public function save_object(int $num_links): void
	{
		if (!$this->config['pedodev_linkprotection_multiplelinks'] || $num_links <= 0)
		{
			return;
		}

		$save_duration = (int)$this->config['pedodev_linkprotection_solveduration'];
		$this->name = 'linkprotection_' . $this->user->data['user_id'];

		$this->data = array(
			'links'	=>	$num_links,
			'time'	=>	time() + $save_duration,
		);

		$this->write_object($save_duration);
	}

	/*
	* Called when a user visits a link without solving a captcha. Decreases their link 'allowance' by 1.
	*/
	public function decrement_remaining_links(): void
	{
		if (empty($this->data) || !isset($this->data['links']))
		{
			return;
		}

		$this->data['links'] -= 1;
		$this->write_object($this->get_remaining_time());
	}

	public function get_remaining_links(): int
	{
		return ((isset($this->data) && isset($this->data['links'])) ? $this->data['links'] : -1);
	}

	public function get_remaining_time(): int
	{
		return ((isset($this->data) && isset($this->data['time'])) ? ($this->data['time'] - time()) : -1);
	}
}