<?php

/*
* This file is part of the Symfony package.
*
* (c) Fabien Potencier <fabien@symfony.com>
*
* For the full copyright and license information, please view the LICENSE
* file that was distributed with this source code.
*/

namespace Symfony\Component\Console\Output;

use Symfony\Component\Console\Exception\InvalidArgumentException;
use Symfony\Component\Console\Exception\RuntimeException;
use Symfony\Component\Console\Formatter\OutputFormatterInterface;

/**
* StreamOutput writes the output to a given stream.
*
* Usage:
*
* $output = new StreamOutput(fopen('php://stdout', 'w'));
*
* As `StreamOutput` can use any stream, you can also use a file:
*
* $output = new StreamOutput(fopen('/path/to/output.log', 'a', false));
*
* @author Fabien Potencier <fabien@symfony.com>
*/
class StreamOutput extends Output
{
private $stream;

/**
* @param resource $stream A stream resource
* @param int $verbosity The verbosity level (one of the VERBOSITY constants in OutputInterface)
* @param bool|null $decorated Whether to decorate messages (null for auto-guessing)
* @param OutputFormatterInterface|null $formatter Output formatter instance (null to use default OutputFormatter)
*
* @throws InvalidArgumentException When first argument is not a real stream
*/
public function __construct($stream, int $verbosity = self::VERBOSITY_NORMAL, bool $decorated = null, OutputFormatterInterface $formatter = null)
{
if (!is_resource($stream) || 'stream' !== get_resource_type($stream)) {
throw new InvalidArgumentException('The StreamOutput class needs a stream as its first argument.');
}

$this->stream = $stream;

if (null === $decorated) {
$decorated = $this->hasColorSupport();
}

parent::__construct($verbosity, $decorated, $formatter);
}

/**
* Gets the stream attached to this StreamOutput instance.
*
* @return resource A stream resource
*/
public function getStream()
{
return $this->stream;
}

/**
* {@inheritdoc}
*/
protected function doWrite($message, $newline)
{
if (false === @fwrite($this->stream, $message) || ($newline && (false === @fwrite($this->stream, PHP_EOL)))) {
// should never happen
throw new RuntimeException('Unable to write output.');
}

fflush($this->stream);
}

/**
* Returns true if the stream supports colorization.
*
* Colorization is disabled if not supported by the stream:
*
* - Windows != 10.0.10586 without Ansicon, ConEmu or Mintty
* - non tty consoles
*
* @return bool true if the stream supports colorization, false otherwise
*/
protected function hasColorSupport()
{
if (DIRECTORY_SEPARATOR === '\\') {
return
function_exists('sapi_windows_vt100_support') && @sapi_windows_vt100_support($this->stream)
|| '10.0.10586' === PHP_WINDOWS_VERSION_MAJOR.'.'.PHP_WINDOWS_VERSION_MINOR.'.'.PHP_WINDOWS_VERSION_BUILD
|| false !== getenv('ANSICON')
|| 'ON' === getenv('ConEmuANSI')
|| 'xterm' === getenv('TERM');
}

return function_exists('posix_isatty') && @posix_isatty($this->stream);
}
}