Screen.php

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<?php
namespace Ubiquity\devtools\cmd;
 
class Screen {
 
    private static $width;
 
    private static $height;
 
    private static $stty;
 
    public static function getWidth() {
        $width = \getenv('COLUMNS');
        if (false !== $width) {
            return (int) \trim($width);
        }
 
        if (null === self::$width) {
            self::initDimensions();
        }
 
        return self::$width ?? 80;
    }
 
    public static function getHeight() {
        $height = \getenv('LINES');
        if (false !== $height) {
            return (int) trim($height);
        }
 
        if (null === self::$height) {
            self::initDimensions();
        }
 
        return self::$height ?? 50;
    }
 
    public static function hasSttyAvailable() {
        if (null !== self::$stty) {
            return self::$stty;
        }
 
        // skip check if exec function is disabled
        if (! \function_exists('exec')) {
            return false;
        }
 
        \exec('stty 2>&1', $output, $exitcode);
 
        return self::$stty = 0 === $exitcode;
    }
 
    private static function initDimensions() {
        if ('\\' === \DIRECTORY_SEPARATOR) {
            if (\preg_match('/^(\d+)x(\d+)(?: \‍((\d+)x(\d+)\‍))?$/', \trim(\getenv('ANSICON')), $matches)) {
                // extract [w, H] from "wxh (WxH)"
                // or [w, h] from "wxh"
                self::$width = (int) $matches[1];
                self::$height = isset($matches[4]) ? (int) $matches[4] : (int) $matches[2];
            } elseif (! self::hasVt100Support() && self::hasSttyAvailable()) {
                // only use stty on Windows if the terminal does not support vt100 (e.g. Windows 7 + git-bash)
                // testing for stty in a Windows 10 vt100-enabled console will implicitly disable vt100 support on STDOUT
                self::initDimensionsUsingStty();
            } elseif (null !== $dimensions = self::getConsoleMode()) {
                // extract [w, h] from "wxh"
                self::$width = (int) $dimensions[0];
                self::$height = (int) $dimensions[1];
            }
        } else {
            self::initDimensionsUsingStty();
        }
    }
 
    private static function hasVt100Support(): bool {
        return \function_exists('sapi_windows_vt100_support') && \sapi_windows_vt100_support(\fopen('php://stdout', 'w'));
    }
 
    private static function initDimensionsUsingStty() {
        if ($sttyString = self::getSttyColumns()) {
            if (\preg_match('/rows.(\d+);.columns.(\d+);/i', $sttyString, $matches)) {
                // extract [w, h] from "rows h; columns w;"
                self::$width = (int) $matches[2];
                self::$height = (int) $matches[1];
            } elseif (\preg_match('/;.(\d+).rows;.(\d+).columns/i', $sttyString, $matches)) {
                // extract [w, h] from "; h rows; w columns"
                self::$width = (int) $matches[2];
                self::$height = (int) $matches[1];
            }
        }
    }
 
    private static function getConsoleMode(): ?array {
        $info = self::readFromProcess('mode CON');
 
        if (null === $info || ! preg_match('/--------+\r?\n.+?(\d+)\r?\n.+?(\d+)\r?\n/', $info, $matches)) {
            return null;
        }
 
        return [
            (int) $matches[2],
            (int) $matches[1]
        ];
    }
 
    private static function getSttyColumns(): ?string {
        return self::readFromProcess('stty -a | grep columns');
    }
 
    private static function readFromProcess(string $command): ?string {
        if (! \function_exists('proc_open')) {
            return null;
        }
 
        $descriptorspec = [
            1 => [
                'pipe',
                'w'
            ],
            2 => [
                'pipe',
                'w'
            ]
        ];
 
        $process = \proc_open($command, $descriptorspec, $pipes, null, null, [
            'suppress_errors' => true
        ]);
        if (! \is_resource($process)) {
            return null;
        }
 
        $info = \stream_get_contents($pipes[1]);
        \fclose($pipes[1]);
        \fclose($pipes[2]);
        \proc_close($process);
 
        return $info;
    }
}