YetiForceCompany/YetiForceCRM

<?php

/**
 * Temporary data handling functionality.
 * It's used in time consuming processes that deal with a large number of entries.
 * It stores data about the last executed element of a given process in order to resume it at a later time while maintaining continuity.
 *
 * @package App
 *
 * @copyright YetiForce S.A.
 * @license   YetiForce Public License 6.5 (licenses/LicenseEN.txt or yetiforce.com)
 * @author    Radosław Skrzypczak <r.skrzypczak@yetiforce.com>
 */

namespace App;

/**
 * Pauser - temporary data handler class.
 */
class Pauser
{
    /** Table name. */
    private const TABLE_NAME = 's_#__pauser';

    /** @var string Entry name */
    private $key;

    /** @var string Value */
    private $value;

    /**
     * Return object instance.
     *
     * @param string $key
     *
     * @return self
     */
    public static function getInstance(string $key): self
    {
        $instance = new self();
        $instance->setKey($key)->load();
        return $instance;
    }

    /**
     * Set key name.
     *
     * @param string $key
     *
     * @return self
     */
    private function setKey(string $key): self
    {
        $this->key = $key;
        return $this;
    }

    /**
     * Load data from database.
     *
     * @return self
     */
    private function load(): self
    {
        $val = (new \App\Db\Query())->select(['value'])->from(self::TABLE_NAME)->where(['key' => $this->key])->scalar();
        $this->value = false === $val ? null : $val;
        return $this;
    }

    /**
     * Set value.
     *
     * @param string $value
     *
     * @return bool
     */
    public function setValue(string $value): bool
    {
        $dbCommand = \App\Db::getInstance()->createCommand();
        if (null === $this->value) {
            $result = $dbCommand->insert(self::TABLE_NAME, ['value' => $value, 'key' => $this->key])->execute();
        } else {
            $result = $dbCommand->update(self::TABLE_NAME, ['value' => $value], ['key' => $this->key])->execute();
        }
        if ($result) {
            $this->value = $value;
        }
        return (bool) $result;
    }

    /**
     * Get value.
     *
     * @return string|null
     */
    public function getValue(): ?string
    {
        return $this->value;
    }

    /**
     * Remove key from database.
     *
     * @return bool
     */
    public function destroy(): bool
    {
        $this->value = null;
        return (bool) \App\Db::getInstance()->createCommand()->delete(self::TABLE_NAME, ['key' => $this->key])->execute();
    }
}