<?php
/**
 * Copyright © 2016 Magento. All rights reserved.
 * See COPYING.txt for license details.
 */

/**
 * Abstract shell command for the static code inspection
 */
namespace Magento\TestFramework\Inspection;

abstract class AbstractCommand
{
    /**
     * @var string
     */
    protected $_reportFile;

    /**
     * @var int
     */
    protected $_lastExitCode;

    /**
     * @var string
     */
    protected $_lastOutput;

    /**
     * @var string
     */
    protected $_lastRunMessage;

    /**
     * Constructor
     *
     * @param string $reportFile Destination file to write inspection report to
     */
    public function __construct($reportFile)
    {
        $this->_reportFile = $reportFile;
    }

    /**
     * Build and execute the shell command
     *
     * @param array $whiteList Files/directories to be inspected
     * @param array $blackList Files/directories to be excluded from the inspection
     * @return bool
     */
    public function run(array $whiteList, array $blackList = [])
    {
        if (file_exists($this->_reportFile)) {
            unlink($this->_reportFile);
        }
        $shellCmd = $this->_buildShellCmd($whiteList, $blackList);
        $result = $this->_execShellCmd($shellCmd);
        $this->_generateLastRunMessage();
        return $result !== false;
    }

    /**
     * Whether the command can be ran on the current environment
     *
     * @return bool
     */
    public function canRun()
    {
        return $this->_execShellCmd($this->_buildVersionShellCmd()) !== false;
    }

    /**
     * Retrieve the shell command version
     *
     * @return string|null
     */
    public function getVersion()
    {
        $versionOutput = $this->_execShellCmd($this->_buildVersionShellCmd());
        if (!$versionOutput) {
            return null;
        }
        return preg_match('/[^\d]*([^\s]+)/', $versionOutput, $matches) ? $matches[1] : $versionOutput;
    }

    /**
     * Get path to the report file
     *
     * @return string
     */
    public function getReportFile()
    {
        return $this->_reportFile;
    }

    /**
     * Build the shell command that outputs the version
     *
     * @return string
     */
    abstract protected function _buildVersionShellCmd();

    /**
     * Build the valid shell command
     *
     * @param array $whiteList
     * @param array $blackList
     * @return string
     */
    abstract protected function _buildShellCmd($whiteList, $blackList);

    /**
     * Execute a shell command on the current environment and return its output or FALSE on failure
     *
     * @param string $shellCmd
     * @return string|false
     */
    protected function _execShellCmd($shellCmd)
    {
        $output = [];
        exec($shellCmd . ' 2>&1', $output, $this->_lastExitCode);
        $this->_lastOutput = implode(PHP_EOL, $output);
        return $this->_lastExitCode === 0 ? $this->_lastOutput : false;
    }

    /**
     * Generate message about last execution result, prepared for output to a user
     *
     * @return \Magento\TestFramework\Inspection\AbstractCommand
     */
    protected function _generateLastRunMessage()
    {
        if ($this->_lastExitCode === null) {
            $this->_lastRunMessage = "Nothing was executed.";
        } elseif (!$this->_lastExitCode) {
            $this->_lastRunMessage = 'Success reported.';
        } elseif (file_exists($this->_reportFile)) {
            $this->_lastRunMessage = "See detailed report in '{$this->_reportFile}'.";
        } else {
            $this->_lastRunMessage = 'Command-line tool reports: ' . $this->_lastOutput;
        }
        return $this;
    }

    /**
     * Return message from the last run of the command
     *
     * @return string
     */
    public function getLastRunMessage()
    {
        return $this->_lastRunMessage;
    }
}