<?php
/**
 * Zend Framework (http://framework.zend.com/)
 *
 * @link      http://github.com/zendframework/zf2 for the canonical source repository
 * @copyright Copyright (c) 2005-2013 Zend Technologies USA Inc. (http://www.zend.com)
 * @license   http://framework.zend.com/license/new-bsd New BSD License
 */

namespace Zend\Console\Adapter;

use Zend\Console\Charset;

/**
 * Virtual buffer adapter
 */
class Virtual extends AbstractAdapter
{
    /**
     * Whether or not mbstring is enabled
     *
     * @var null|bool
     */
    protected static $hasMBString;

    /**
     * Results of mode system command
     *
     * @var mixed
     */
    protected $modeResult;

    /**
     * Determine and return current console width.
     *
     * @return int
     */
    public function getWidth()
    {
        static $width;
        if ($width > 0) {
            return $width;
        }

        // Try to read console size from "mode" command
        if ($this->modeResult === null) {
            $this->runProbeCommand();
        }

        if (preg_match('/Columns\:\s+(\d+)/', $this->modeResult, $matches)) {
            $width = $matches[1];
        } else {
            $width = parent::getWidth();
        }

        return $width;
    }

    /**
     * Determine and return current console height.
     *
     * @return false|int
     */
    public function getHeight()
    {
        static $height;
        if ($height > 0) {
            return $height;
        }

        // Try to read console size from "mode" command
        if ($this->modeResult === null) {
            $this->runProbeCommand();
        }

        if (preg_match('/Rows\:\s+(\d+)/', $this->modeResult, $matches)) {
            $height = $matches[1];
        } else {
            $height = parent::getHeight();
        }

        return $height;
    }

    /**
     * Run and store the results of mode command
     *
     * @return void
     */
    protected function runProbeCommand()
    {
        exec('mode', $output, $return);
        if ($return || !count($output)) {
            $this->modeResult = '';
        } else {
            $this->modeResult = trim(implode('', $output));
        }
    }

    /**
     * Check if console is UTF-8 compatible
     *
     * @return bool
     */
    public function isUtf8()
    {
        // Try to read code page info from "mode" command
        if ($this->modeResult === null) {
            $this->runProbeCommand();
        }

        if (preg_match('/Code page\:\s+(\d+)/', $this->modeResult, $matches)) {
            return (int) $matches[1] == 65001;
        }

        return false;
    }

    /**
     * Return current console window title.
     *
     * @return string
     */
    public function getTitle()
    {
        // Try to use powershell to retrieve console window title
        exec('powershell -command "write $Host.UI.RawUI.WindowTitle"', $output, $result);
        if ($result || !$output) {
            return '';
        }

        return trim($output, "\r\n");
    }

    /**
     * Set Console charset to use.
     *
     * @param Charset\CharsetInterface $charset
     */
    public function setCharset(Charset\CharsetInterface $charset)
    {
        $this->charset = $charset;
    }

    /**
     * Get charset currently in use by this adapter.
     *
     * @return Charset\CharsetInterface $charset
     */
    public function getCharset()
    {
        if ($this->charset === null) {
            $this->charset = $this->getDefaultCharset();
        }

        return $this->charset;
    }

    /**
     * @return Charset\AsciiExtended
     */
    public function getDefaultCharset()
    {
        return new Charset\AsciiExtended;
    }

    /**
     * Switch to UTF mode
     *
     * @return void
     */
    protected function switchToUtf8()
    {
        shell_exec('mode con cp select=65001');
    }
}
