sakura/libraries/ActionCode.php

<?php
namespace Sakura;

/**
 * Used to generate one-time keys for user automatic user actions e.g. account activation.
 * 
 * @package Sakura
 * @author Julian van de Groep <me@flash.moe>
 */
class ActionCode
{
    /**
     * Generate an Action Code.
     * 
     * @param string $action The identifier of the action.
     * @param int $user The user this action code is intended for (leave 0 for universal).
     * 
     * @return string The action code given to the user.
     */
    public static function generate($action, $user = 0)
    {
        // Generate a code
        $code = uniqid();

        // Insert it
        Database::insert('actioncodes', [
            'code_action' => $action,
            'user_id' => $user,
            'action_code' => $code,
        ]);

        // Return the code
        return $code;
    }

    /**
     * Validate an action code.
     * 
     * @param string $action The action identifier.
     * @param string $code The action code.
     * @param int $user The id of the user validating this code.
     * @param bool $invalidate Set if the code should be invalidated once validated.
     * 
     * @return bool Boolean indicating success.
     */
    public static function validate($action, $code, $user = 0, $invalidate = true)
    {
        // Fetch the code from the db
        $get = Database::count('actioncodes', [
            'code_action' => [$action, '='],
            'action_code' => [$code, '='],
            'user_id' => [$user, '='],
        ]);

        // Invalidate the code if requested
        if ($invalidate) {
            self::invalidate($code);
        }

        // Return the result
        return $get[0] > 0;
    }

    /**
     * Make a code invalid.
     * 
     * @param string $code The code that is being invalidated.
     */
    public static function invalidate($code)
    {
        Database::delete('actioncodes', [
            'code_action' => [$code, '='],
        ]);
    }
}