<?php
/**
 * Copyright © 2015 Magento. All rights reserved.
 * See COPYING.txt for license details.
 */

namespace Magento\Update;

/**
 * Class which provides access to the current status of the Magento updater application.
 *
 * Each job is using this class to share information about its current status.
 * Current status can be seen on the updater app web page.
 */
class Status
{
    /**
     * Path to a file, which content is displayed on the updater web page.
     *
     * @var string
     */
    protected $statusFilePath;

    /**
     * Path to a log file, which contains all the information displayed on the web page.
     *
     * Note that it can be cleared only manually, it is not cleared by clear() method.
     *
     * @var string
     */
    protected $logFilePath;

    /**
     * Path to a flag, which exists when updater app is running.
     *
     * @var string
     */
    protected $updateInProgressFlagFilePath;

    /**
     * Path to a flag, which exists when error occurred during updater app execution.
     *
     * @var string
     */
    protected $updateErrorFlagFilePath;

    /**
     * Initialize.
     *
     * @param string|null $statusFilePath
     * @param string|null $logFilePath
     * @param string|null $updateInProgressFlagFilePath
     * @param string|null $updateErrorFlagFilePath
     */
    public function __construct(
        $statusFilePath = null,
        $logFilePath = null,
        $updateInProgressFlagFilePath = null,
        $updateErrorFlagFilePath = null
    ) {
        $this->statusFilePath = $statusFilePath ? $statusFilePath : MAGENTO_BP . '/var/.update_status.txt';
        $this->logFilePath = $logFilePath ? $logFilePath : MAGENTO_BP . '/var/update_status.log';
        $this->updateInProgressFlagFilePath = $updateInProgressFlagFilePath
            ? $updateInProgressFlagFilePath
            : MAGENTO_BP . '/var/.update_in_progress.flag';
        $this->updateErrorFlagFilePath = $updateErrorFlagFilePath
            ? $updateErrorFlagFilePath
            : MAGENTO_BP . '/var/.update_error.flag';
    }

    /**
     * Get current updater application status.
     *
     * @return string
     */
    public function get()
    {
        if (file_exists($this->statusFilePath)) {
            return file_get_contents($this->statusFilePath);
        }
        return '';
    }

    /**
     * Add status update.
     *
     * Add information to a temporary file which is used for status display on a web page and to a permanent status log.
     *
     * @param string $text
     * @return $this
     * @throws \RuntimeException
     */
    public function add($text)
    {
        $currentUtcTime = '[' . date('Y-m-d H:i:s T', time()) . '] ';
        $text = $currentUtcTime . $text;
        $this->writeMessageToFile($text, $this->logFilePath);
        $this->writeMessageToFile($text, $this->statusFilePath);
        return $this;
    }

    /**
     * Add status update to show progress
     *
     * @param string $text
     * @return $this
     * @throws \RuntimeException
     */
    public function addWithoutNewLine($text)
    {
        $this->writeMessageToFile($text, $this->logFilePath, false);
        $this->writeMessageToFile($text, $this->statusFilePath, false);
        return $this;
    }

    /**
     * Write status information to the file.
     *
     * @param string $text
     * @param string $filePath
     * @param bool $newline
     * @return $this
     * @throws \RuntimeException
     */
    protected function writeMessageToFile($text, $filePath, $newline = true)
    {
        $isNewFile = !file_exists($filePath);
        if (!$isNewFile && file_get_contents($filePath)) {
            $text = $newline ? PHP_EOL . "{$text}" :"{$text}";
        }
        if (false === file_put_contents($filePath, $text, FILE_APPEND)) {
            throw new \RuntimeException(sprintf('Cannot add status information to "%s"', $filePath));
        }
        if ($isNewFile) {
            chmod($filePath, 0777);
        }
        return $this;
    }

    /**
     * Clear current status text.
     *
     * Note that this method does not clear status information from the permanent status log.
     *
     * @return $this
     * @throws \RuntimeException
     */
    public function clear()
    {
        if (!file_exists($this->statusFilePath)) {
            return $this;
        } else if (false === file_put_contents($this->statusFilePath, '')) {
            throw new \RuntimeException(sprintf('Cannot clear status information from "%s"', $this->statusFilePath));
        }
        return $this;
    }

    /**
     * Check if updater application is running.
     *
     * @return bool
     */
    public function isUpdateInProgress()
    {
        return file_exists($this->updateInProgressFlagFilePath);
    }

    /**
     * Set current updater app status: true if update is in progress, false otherwise.
     *
     * @param bool $isInProgress
     * @return $this
     */
    public function setUpdateInProgress($isInProgress = true)
    {
        return $this->setFlagValue($this->updateInProgressFlagFilePath, $isInProgress);
    }

    /**
     * Check if error has occurred during updater application execution.
     *
     * @return bool
     */
    public function isUpdateError()
    {
        return file_exists($this->updateErrorFlagFilePath);
    }

    /**
     * Set current updater app status: true if error occurred during update app execution, false otherwise.
     *
     * @param bool $isErrorOccurred
     * @return $this
     */
    public function setUpdateError($isErrorOccurred = true)
    {
        return $this->setFlagValue($this->updateErrorFlagFilePath, $isErrorOccurred);
    }

    /**
     * Create flag in case when value is set to 'true', remove it if value is set to 'false'.
     *
     * @param string $pathToFlagFile
     * @param bool $value
     * @throws \RuntimeException
     * @return $this
     */
    protected function setFlagValue($pathToFlagFile, $value)
    {
        if ($value) {
            $updateInProgressFlagFile = fopen($pathToFlagFile, 'w');
            if (!$updateInProgressFlagFile) {
                throw new \RuntimeException(sprintf('"%s" cannot be created.', $pathToFlagFile));
            }
            fclose($updateInProgressFlagFile);
        } else if (file_exists($pathToFlagFile)) {
            unlink($pathToFlagFile);
        }
        return $this;
    }
}