yii2-swiftmailer/framework/yii/helpers/BaseConsole.php

<?php
/**
 * @link http://www.yiiframework.com/
 * @copyright Copyright (c) 2008 Yii Software LLC
 * @license http://www.yiiframework.com/license/
 */

namespace yii\helpers;

/**
 * BaseConsole provides concrete implementation for [[Console]].
 *
 * Do not use BaseConsole. Use [[Console]] instead.
 *
 * @author Carsten Brandt <mail@cebe.cc>
 * @since 2.0
 */
class BaseConsole
{
	const FG_BLACK  = 30;
	const FG_RED    = 31;
	const FG_GREEN  = 32;
	const FG_YELLOW = 33;
	const FG_BLUE   = 34;
	const FG_PURPLE = 35;
	const FG_CYAN   = 36;
	const FG_GREY   = 37;

	const BG_BLACK  = 40;
	const BG_RED    = 41;
	const BG_GREEN  = 42;
	const BG_YELLOW = 43;
	const BG_BLUE   = 44;
	const BG_PURPLE = 45;
	const BG_CYAN   = 46;
	const BG_GREY   = 47;

	const RESET       = 0;
	const NORMAL      = 0;
	const BOLD        = 1;
	const ITALIC      = 3;
	const UNDERLINE   = 4;
	const BLINK       = 5;
	const NEGATIVE    = 7;
	const CONCEALED   = 8;
	const CROSSED_OUT = 9;
	const FRAMED      = 51;
	const ENCIRCLED   = 52;
	const OVERLINED   = 53;

	/**
	 * Moves the terminal cursor up by sending ANSI control code CUU to the terminal.
	 * If the cursor is already at the edge of the screen, this has no effect.
	 * @param integer $rows number of rows the cursor should be moved up
	 */
	public static function moveCursorUp($rows = 1)
	{
		echo "\033[" . (int)$rows . 'A';
	}

	/**
	 * Moves the terminal cursor down by sending ANSI control code CUD to the terminal.
	 * If the cursor is already at the edge of the screen, this has no effect.
	 * @param integer $rows number of rows the cursor should be moved down
	 */
	public static function moveCursorDown($rows = 1)
	{
		echo "\033[" . (int)$rows . 'B';
	}

	/**
	 * Moves the terminal cursor forward by sending ANSI control code CUF to the terminal.
	 * If the cursor is already at the edge of the screen, this has no effect.
	 * @param integer $steps number of steps the cursor should be moved forward
	 */
	public static function moveCursorForward($steps = 1)
	{
		echo "\033[" . (int)$steps . 'C';
	}

	/**
	 * Moves the terminal cursor backward by sending ANSI control code CUB to the terminal.
	 * If the cursor is already at the edge of the screen, this has no effect.
	 * @param integer $steps number of steps the cursor should be moved backward
	 */
	public static function moveCursorBackward($steps = 1)
	{
		echo "\033[" . (int)$steps . 'D';
	}

	/**
	 * Moves the terminal cursor to the beginning of the next line by sending ANSI control code CNL to the terminal.
	 * @param integer $lines number of lines the cursor should be moved down
	 */
	public static function moveCursorNextLine($lines = 1)
	{
		echo "\033[" . (int)$lines . 'E';
	}

	/**
	 * Moves the terminal cursor to the beginning of the previous line by sending ANSI control code CPL to the terminal.
	 * @param integer $lines number of lines the cursor should be moved up
	 */
	public static function moveCursorPrevLine($lines = 1)
	{
		echo "\033[" . (int)$lines . 'F';
	}

	/**
	 * Moves the cursor to an absolute position given as column and row by sending ANSI control code CUP or CHA to the terminal.
	 * @param integer $column 1-based column number, 1 is the left edge of the screen.
	 * @param integer|null $row 1-based row number, 1 is the top edge of the screen. if not set, will move cursor only in current line.
	 */
	public static function moveCursorTo($column, $row = null)
	{
		if ($row === null) {
			echo "\033[" . (int)$column . 'G';
		} else {
			echo "\033[" . (int)$row . ';' . (int)$column . 'H';
		}
	}

	/**
	 * Scrolls whole page up by sending ANSI control code SU to the terminal.
	 * New lines are added at the bottom. This is not supported by ANSI.SYS used in windows.
	 * @param int $lines number of lines to scroll up
	 */
	public static function scrollUp($lines = 1)
	{
		echo "\033[" . (int)$lines . "S";
	}

	/**
	 * Scrolls whole page down by sending ANSI control code SD to the terminal.
	 * New lines are added at the top. This is not supported by ANSI.SYS used in windows.
	 * @param int $lines number of lines to scroll down
	 */
	public static function scrollDown($lines = 1)
	{
		echo "\033[" . (int)$lines . "T";
	}

	/**
	 * Saves the current cursor position by sending ANSI control code SCP to the terminal.
	 * Position can then be restored with [[restoreCursorPosition()]].
	 */
	public static function saveCursorPosition()
	{
		echo "\033[s";
	}

	/**
	 * Restores the cursor position saved with [[saveCursorPosition()]] by sending ANSI control code RCP to the terminal.
	 */
	public static function restoreCursorPosition()
	{
		echo "\033[u";
	}

	/**
	 * Hides the cursor by sending ANSI DECTCEM code ?25l to the terminal.
	 * Use [[showCursor()]] to bring it back.
	 * Do not forget to show cursor when your application exits. Cursor might stay hidden in terminal after exit.
	 */
	public static function hideCursor()
	{
		echo "\033[?25l";
	}

	/**
	 * Will show a cursor again when it has been hidden by [[hideCursor()]]  by sending ANSI DECTCEM code ?25h to the terminal.
	 */
	public static function showCursor()
	{
		echo "\033[?25h";
	}

	/**
	 * Clears entire screen content by sending ANSI control code ED with argument 2 to the terminal.
	 * Cursor position will not be changed.
	 * **Note:** ANSI.SYS implementation used in windows will reset cursor position to upper left corner of the screen.
	 */
	public static function clearScreen()
	{
		echo "\033[2J";
	}

	/**
	 * Clears text from cursor to the beginning of the screen by sending ANSI control code ED with argument 1 to the terminal.
	 * Cursor position will not be changed.
	 */
	public static function clearScreenBeforeCursor()
	{
		echo "\033[1J";
	}

	/**
	 * Clears text from cursor to the end of the screen by sending ANSI control code ED with argument 0 to the terminal.
	 * Cursor position will not be changed.
	 */
	public static function clearScreenAfterCursor()
	{
		echo "\033[0J";
	}

	/**
	 * Clears the line, the cursor is currently on by sending ANSI control code EL with argument 2 to the terminal.
	 * Cursor position will not be changed.
	 */
	public static function clearLine()
	{
		echo "\033[2K";
	}

	/**
	 * Clears text from cursor position to the beginning of the line by sending ANSI control code EL with argument 1 to the terminal.
	 * Cursor position will not be changed.
	 */
	public static function clearLineBeforeCursor()
	{
		echo "\033[1K";
	}

	/**
	 * Clears text from cursor position to the end of the line by sending ANSI control code EL with argument 0 to the terminal.
	 * Cursor position will not be changed.
	 */
	public static function clearLineAfterCursor()
	{
		echo "\033[0K";
	}

	/**
	 * Returns the ANSI format code.
	 *
	 * @param array $format An array containing formatting values.
	 * You can pass any of the FG_*, BG_* and TEXT_* constants
	 * and also [[xtermFgColor]] and [[xtermBgColor]] to specify a format.
	 * @return string The ANSI format code according to the given formatting constants.
	 */
	public static function ansiFormatCode($format)
	{
		return "\033[" . implode(';', $format) . 'm';
	}

	/**
	 * Echoes an ANSI format code that affects the formatting of any text that is printed afterwards.
	 *
	 * @param array $format An array containing formatting values.
	 * You can pass any of the FG_*, BG_* and TEXT_* constants
	 * and also [[xtermFgColor]] and [[xtermBgColor]] to specify a format.
	 * @see ansiFormatCode()
	 * @see ansiFormatEnd()
	 */
	public static function beginAnsiFormat($format)
	{
		echo "\033[" . implode(';', $format) . 'm';
	}

	/**
	 * Resets any ANSI format set by previous method [[ansiFormatBegin()]]
	 * Any output after this will have default text format.
	 * This is equal to calling
	 *
	 * ```php
	 * echo Console::ansiFormatCode([Console::RESET])
	 * ```
	 */
	public static function endAnsiFormat()
	{
		echo "\033[0m";
	}

	/**
	 * Will return a string formatted with the given ANSI style
	 *
	 * @param string $string the string to be formatted
	 * @param array $format An array containing formatting values.
	 * You can pass any of the FG_*, BG_* and TEXT_* constants
	 * and also [[xtermFgColor]] and [[xtermBgColor]] to specify a format.
	 * @return string
	 */
	public static function ansiFormat($string, $format = [])
	{
		$code = implode(';', $format);
		return "\033[0m" . ($code !== '' ? "\033[" . $code . "m" : '') . $string . "\033[0m";
	}

	/**
	 * Returns the ansi format code for xterm foreground color.
	 * You can pass the return value of this to one of the formatting methods:
	 * [[ansiFormat]], [[ansiFormatCode]], [[beginAnsiFormat]]
	 *
	 * @param integer $colorCode xterm color code
	 * @return string
	 * @see http://en.wikipedia.org/wiki/Talk:ANSI_escape_code#xterm-256colors
	 */
	public static function xtermFgColor($colorCode)
	{
		return '38;5;' . $colorCode;
	}

	/**
	 * Returns the ansi format code for xterm background color.
	 * You can pass the return value of this to one of the formatting methods:
	 * [[ansiFormat]], [[ansiFormatCode]], [[beginAnsiFormat]]
	 *
	 * @param integer $colorCode xterm color code
	 * @return string
	 * @see http://en.wikipedia.org/wiki/Talk:ANSI_escape_code#xterm-256colors
	 */
	public static function xtermBgColor($colorCode)
	{
		return '48;5;' . $colorCode;
	}

	/**
	 * Strips ANSI control codes from a string
	 *
	 * @param string $string String to strip
	 * @return string
	 */
	public static function stripAnsiFormat($string)
	{
		return preg_replace('/\033\[[\d;?]*\w/', '', $string);
	}

	/**
	 * Converts an ANSI formatted string to HTML
	 * @param $string
	 * @return mixed
	 */
	// TODO rework/refactor according to https://github.com/yiisoft/yii2/issues/746
	public static function ansiToHtml($string)
	{
		$tags = 0;
		return preg_replace_callback(
			'/\033\[[\d;]+m/',
			function ($ansi) use (&$tags) {
				$styleA = [];
				foreach (explode(';', $ansi) as $controlCode) {
					switch ($controlCode) {
						case self::FG_BLACK:
							$style = ['color' => '#000000'];
							break;
						case self::FG_BLUE:
							$style = ['color' => '#000078'];
							break;
						case self::FG_CYAN:
							$style = ['color' => '#007878'];
							break;
						case self::FG_GREEN:
							$style = ['color' => '#007800'];
							break;
						case self::FG_GREY:
							$style = ['color' => '#787878'];
							break;
						case self::FG_PURPLE:
							$style = ['color' => '#780078'];
							break;
						case self::FG_RED:
							$style = ['color' => '#780000'];
							break;
						case self::FG_YELLOW:
							$style = ['color' => '#787800'];
							break;
						case self::BG_BLACK:
							$style = ['background-color' => '#000000'];
							break;
						case self::BG_BLUE:
							$style = ['background-color' => '#000078'];
							break;
						case self::BG_CYAN:
							$style = ['background-color' => '#007878'];
							break;
						case self::BG_GREEN:
							$style = ['background-color' => '#007800'];
							break;
						case self::BG_GREY:
							$style = ['background-color' => '#787878'];
							break;
						case self::BG_PURPLE:
							$style = ['background-color' => '#780078'];
							break;
						case self::BG_RED:
							$style = ['background-color' => '#780000'];
							break;
						case self::BG_YELLOW:
							$style = ['background-color' => '#787800'];
							break;
						case self::BOLD:
							$style = ['font-weight' => 'bold'];
							break;
						case self::ITALIC:
							$style = ['font-style' => 'italic'];
							break;
						case self::UNDERLINE:
							$style = ['text-decoration' => ['underline']];
							break;
						case self::OVERLINED:
							$style = ['text-decoration' => ['overline']];
							break;
						case self::CROSSED_OUT:
							$style = ['text-decoration' => ['line-through']];
							break;
						case self::BLINK:
							$style = ['text-decoration' => ['blink']];
							break;
						case self::NEGATIVE: // ???
						case self::CONCEALED:
						case self::ENCIRCLED:
						case self::FRAMED:
							// TODO allow resetting codes
							break;
						case 0: // ansi reset
							$return = '';
							for ($n = $tags; $tags > 0; $tags--) {
								$return .= '</span>';
							}
							return $return;
					}

					$styleA = ArrayHelper::merge($styleA, $style);
				}
				$styleString[] = [];
				foreach ($styleA as $name => $content) {
					if ($name === 'text-decoration') {
						$content = implode(' ', $content);
					}
					$styleString[] = $name . ':' . $content;
				}
				$tags++;
				return '<span' . (!empty($styleString) ? 'style="' . implode(';', $styleString) : '') . '>';
			},
			$string
		);
	}

	// TODO rework/refactor according to https://github.com/yiisoft/yii2/issues/746
	public function markdownToAnsi()
	{
		// TODO implement
	}

	/**
	 * Converts a string to ansi formatted by replacing patterns like %y (for yellow) with ansi control codes
	 *
	 * Uses almost the same syntax as https://github.com/pear/Console_Color2/blob/master/Console/Color2.php
	 * The conversion table is: ('bold' meaning 'light' on some
	 * terminals). It's almost the same conversion table irssi uses.
	 * <pre>
	 *                  text      text            background
	 *      ------------------------------------------------
	 *      %k %K %0    black     dark grey       black
	 *      %r %R %1    red       bold red        red
	 *      %g %G %2    green     bold green      green
	 *      %y %Y %3    yellow    bold yellow     yellow
	 *      %b %B %4    blue      bold blue       blue
	 *      %m %M %5    magenta   bold magenta    magenta
	 *      %p %P       magenta (think: purple)
	 *      %c %C %6    cyan      bold cyan       cyan
	 *      %w %W %7    white     bold white      white
	 *
	 *      %F     Blinking, Flashing
	 *      %U     Underline
	 *      %8     Reverse
	 *      %_,%9  Bold
	 *
	 *      %n     Resets the color
	 *      %%     A single %
	 * </pre>
	 * First param is the string to convert, second is an optional flag if
	 * colors should be used. It defaults to true, if set to false, the
	 * colorcodes will just be removed (And %% will be transformed into %)
	 *
	 * @param string $string  String to convert
	 * @param bool   $colored Should the string be colored?
	 * @return string
	 */
	// TODO rework/refactor according to https://github.com/yiisoft/yii2/issues/746
	public static function renderColoredString($string, $colored = true)
	{
		static $conversions = [
			'%y' => [self::FG_YELLOW],
			'%g' => [self::FG_GREEN],
			'%b' => [self::FG_BLUE],
			'%r' => [self::FG_RED],
			'%p' => [self::FG_PURPLE],
			'%m' => [self::FG_PURPLE],
			'%c' => [self::FG_CYAN],
			'%w' => [self::FG_GREY],
			'%k' => [self::FG_BLACK],
			'%n' => [0], // reset
			'%Y' => [self::FG_YELLOW, self::BOLD],
			'%G' => [self::FG_GREEN, self::BOLD],
			'%B' => [self::FG_BLUE, self::BOLD],
			'%R' => [self::FG_RED, self::BOLD],
			'%P' => [self::FG_PURPLE, self::BOLD],
			'%M' => [self::FG_PURPLE, self::BOLD],
			'%C' => [self::FG_CYAN, self::BOLD],
			'%W' => [self::FG_GREY, self::BOLD],
			'%K' => [self::FG_BLACK, self::BOLD],
			'%N' => [0, self::BOLD],
			'%3' => [self::BG_YELLOW],
			'%2' => [self::BG_GREEN],
			'%4' => [self::BG_BLUE],
			'%1' => [self::BG_RED],
			'%5' => [self::BG_PURPLE],
			'%6' => [self::BG_PURPLE],
			'%7' => [self::BG_CYAN],
			'%0' => [self::BG_GREY],
			'%F' => [self::BLINK],
			'%U' => [self::UNDERLINE],
			'%8' => [self::NEGATIVE],
			'%9' => [self::BOLD],
			'%_' => [self::BOLD],
		];

		if ($colored) {
			$string = str_replace('%%', '% ', $string);
			foreach ($conversions as $key => $value) {
				$string = str_replace(
					$key,
					static::ansiFormatCode($value),
					$string
				);
			}
			$string = str_replace('% ', '%', $string);
		} else {
			$string = preg_replace('/%((%)|.)/', '$2', $string);
		}
		return $string;
	}

	/**
	 * Escapes % so they don't get interpreted as color codes when
	 * the string is parsed by [[renderColoredString]]
	 *
	 * @param string $string String to escape
	 *
	 * @access public
	 * @return string
	 */
	// TODO rework/refactor according to https://github.com/yiisoft/yii2/issues/746
	public static function escape($string)
	{
		return str_replace('%', '%%', $string);
	}

	/**
	 * Returns true if the stream supports colorization. ANSI colors are disabled if not supported by the stream.
	 *
	 * - windows without ansicon
	 * - not tty consoles
	 *
	 * @param mixed $stream
	 * @return bool true if the stream supports ANSI colors, otherwise false.
	 */
	public static function streamSupportsAnsiColors($stream)
	{
		return DIRECTORY_SEPARATOR == '\\'
			? getenv('ANSICON') !== false || getenv('ConEmuANSI') === 'ON'
			: function_exists('posix_isatty') && @posix_isatty($stream);
	}

	/**
	 * Returns true if the console is running on windows
	 * @return bool
	 */
	public static function isRunningOnWindows()
	{
		return DIRECTORY_SEPARATOR == '\\';
	}

	/**
	 * Usage: list($width, $height) = ConsoleHelper::getScreenSize();
	 *
	 * @param bool $refresh whether to force checking and not re-use cached size value.
	 * This is useful to detect changing window size while the application is running but may
	 * not get up to date values on every terminal.
	 * @return array|boolean An array of ($width, $height) or false when it was not able to determine size.
	 */
	public static function getScreenSize($refresh = false)
	{
		static $size;
		if ($size !== null && !$refresh) {
			return $size;
		}

		if (static::isRunningOnWindows()) {
			$output = [];
			exec('mode con', $output);
			if (isset($output) && strpos($output[1], 'CON') !== false) {
				return $size = [(int)preg_replace('~[^0-9]~', '', $output[3]), (int)preg_replace('~[^0-9]~', '', $output[4])];
			}
		} else {
			// try stty if available
			$stty = [];
			if (exec('stty -a 2>&1', $stty) && preg_match('/rows\s+(\d+);\s*columns\s+(\d+);/mi', implode(' ', $stty), $matches)) {
				return $size = [$matches[2], $matches[1]];
			}

			// fallback to tput, which may not be updated on terminal resize
			if (($width = (int) exec('tput cols 2>&1')) > 0 && ($height = (int) exec('tput lines 2>&1')) > 0) {
				return $size = [$width, $height];
			}

			// fallback to ENV variables, which may not be updated on terminal resize
			if (($width = (int) getenv('COLUMNS')) > 0 && ($height = (int) getenv('LINES')) > 0) {
				return $size = [$width, $height];
			}
		}

		return $size = false;
	}

	/**
	 * Gets input from STDIN and returns a string right-trimmed for EOLs.
	 *
	 * @param bool $raw If set to true, returns the raw string without trimming
	 * @return string the string read from stdin
	 */
	public static function stdin($raw = false)
	{
		return $raw ? fgets(STDIN) : rtrim(fgets(STDIN), PHP_EOL);
	}

	/**
	 * Prints a string to STDOUT.
	 *
	 * @param string $string the string to print
	 * @return int|boolean Number of bytes printed or false on error
	 */
	public static function stdout($string)
	{
		return fwrite(STDOUT, $string);
	}

	/**
	 * Prints a string to STDERR.
	 *
	 * @param string $string the string to print
	 * @return int|boolean Number of bytes printed or false on error
	 */
	public static function stderr($string)
	{
		return fwrite(STDERR, $string);
	}

	/**
	 * Asks the user for input. Ends when the user types a carriage return (PHP_EOL). Optionally, It also provides a
	 * prompt.
	 *
	 * @param string $prompt the prompt to display before waiting for input (optional)
	 * @return string the user's input
	 */
	public static function input($prompt = null)
	{
		if (isset($prompt)) {
			static::stdout($prompt);
		}
		return static::stdin();
	}

	/**
	 * Prints text to STDOUT appended with a carriage return (PHP_EOL).
	 *
	 * @param string $string the text to print
	 * @return integer|boolean number of bytes printed or false on error.
	 */
	public static function output($string = null)
	{
		return static::stdout($string . PHP_EOL);
	}

	/**
	 * Prints text to STDERR appended with a carriage return (PHP_EOL).
	 *
	 * @param string $string the text to print
	 * @return integer|boolean number of bytes printed or false on error.
	 */
	public static function error($string = null)
	{
		return static::stderr($string . PHP_EOL);
	}

	/**
	 * Prompts the user for input and validates it
	 *
	 * @param string $text prompt string
	 * @param array $options the options to validate the input:
	 *  - required: whether it is required or not
	 *  - default: default value if no input is inserted by the user
	 *  - pattern: regular expression pattern to validate user input
	 *  - validator: a callable function to validate input. The function must accept two parameters:
	 *      - $input: the user input to validate
	 *      - $error: the error value passed by reference if validation failed.
	 * @return string the user input
	 */
	public static function prompt($text, $options = [])
	{
		$options = ArrayHelper::merge(
			[
				'required'  => false,
				'default'   => null,
				'pattern'   => null,
				'validator' => null,
				'error'     => 'Invalid input.',
			],
			$options
		);
		$error   = null;

		top:
		$input = $options['default']
			? static::input("$text [" . $options['default'] . ']: ')
			: static::input("$text: ");

		if (!strlen($input)) {
			if (isset($options['default'])) {
				$input = $options['default'];
			} elseif ($options['required']) {
				static::output($options['error']);
				goto top;
			}
		} elseif ($options['pattern'] && !preg_match($options['pattern'], $input)) {
			static::output($options['error']);
			goto top;
		} elseif ($options['validator'] &&
			!call_user_func_array($options['validator'], [$input, &$error])
		) {
			static::output(isset($error) ? $error : $options['error']);
			goto top;
		}

		return $input;
	}

	/**
	 * Asks user to confirm by typing y or n.
	 *
	 * @param string $message to echo out before waiting for user input
	 * @param boolean $default this value is returned if no selection is made.
	 * @return boolean whether user confirmed
	 */
	public static function confirm($message, $default = true)
	{
		echo $message . ' (yes|no) [' . ($default ? 'yes' : 'no') . ']:';
		$input = trim(static::stdin());
		return empty($input) ? $default : !strncasecmp($input, 'y', 1);
	}

	/**
	 * Gives the user an option to choose from. Giving '?' as an input will show
	 * a list of options to choose from and their explanations.
	 *
	 * @param string $prompt the prompt message
	 * @param array  $options Key-value array of options to choose from
	 *
	 * @return string An option character the user chose
	 */
	public static function select($prompt, $options = [])
	{
		top:
		static::stdout("$prompt [" . implode(',', array_keys($options)) . ",?]: ");
		$input = static::stdin();
		if ($input === '?') {
			foreach ($options as $key => $value) {
				static::output(" $key - $value");
			}
			static::output(" ? - Show help");
			goto top;
		} elseif (!in_array($input, array_keys($options))) {
			goto top;
		}
		return $input;
	}

	private static $_progressStart;
	private static $_progressWidth;
	private static $_progressPrefix;

	/**
	 * Starts display of a progress bar on screen.
	 *
	 * This bar will be updated by [[updateProgress()]] and my be ended by [[endProgress()]].
	 *
	 * The following example shows a simple usage of a progress bar:
	 *
	 * ```php
	 * Console::startProgress(0, 1000);
	 * for ($n = 1; $n <= 1000; $n++) {
	 *     usleep(1000);
	 *     Console::updateProgress($n, 1000);
	 * }
	 * Console::endProgress();
	 * ```
	 *
	 * Git clone like progress (showing only status information):
	 * ```php
	 * Console::startProgress(0, 1000, 'Counting objects: ', false);
	 * for ($n = 1; $n <= 1000; $n++) {
	 *     usleep(1000);
	 *     Console::updateProgress($n, 1000);
	 * }
	 * Console::endProgress("done." . PHP_EOL);
	 * ```
	 *
	 * @param integer $done the number of items that are completed.
	 * @param integer $total the total value of items that are to be done.
	 * @param string $prefix an optional string to display before the progress bar.
	 * Default to empty string which results in no prefix to be displayed.
	 * @param integer|boolean $width optional width of the progressbar. This can be an integer representing
	 * the number of characters to display for the progress bar or a float between 0 and 1 representing the
	 * percentage of screen with the progress bar may take. It can also be set to false to disable the
	 * bar and only show progress information like percent, number of items and ETA.
	 * If not set, the bar will be as wide as the screen. Screen size will be detected using [[getScreenSize()]].
	 * @see startProgress
	 * @see updateProgress
	 * @see endProgress
	 */
	public static function startProgress($done, $total, $prefix = '', $width = null)
	{
		self::$_progressStart = time();
		self::$_progressWidth = $width;
		self::$_progressPrefix = $prefix;

		static::updateProgress($done, $total);
	}

	/**
	 * Updates a progress bar that has been started by [[startProgress()]].
	 *
	 * @param integer $done the number of items that are completed.
	 * @param integer $total the total value of items that are to be done.
	 * @param string $prefix an optional string to display before the progress bar.
	 * Defaults to null meaning the prefix specified by [[startProgress()]] will be used.
	 * If prefix is specified it will update the prefix that will be used by later calls.
	 * @see startProgress
	 * @see endProgress
	 */
	public static function updateProgress($done, $total, $prefix = null)
	{
		$width = self::$_progressWidth;
		if ($width === false) {
			$width = 0;
		} else {
			$screenSize = static::getScreenSize(true);
			if ($screenSize === false && $width < 1) {
				$width = 0;
			} elseif ($width === null) {
				$width = $screenSize[0];
			} elseif ($width > 0 && $width < 1) {
				$width = floor($screenSize[0] * $width);
			}
		}
		if ($prefix === null) {
			$prefix = self::$_progressPrefix;
		} else {
			self::$_progressPrefix = $prefix;
		}
		$width -= mb_strlen($prefix);

		$percent = ($total == 0) ? 1 : $done / $total;
		$info = sprintf("%d%% (%d/%d)", $percent * 100, $done, $total);

		if ($done > $total || $done == 0) {
			$info .= ' ETA: n/a';
		} elseif ($done < $total) {
			$rate = (time() - self::$_progressStart) / $done;
			$info .= sprintf(' ETA: %d sec.', $rate * ($total - $done));
		}

		$width -= 3 + mb_strlen($info);
		// skipping progress bar on very small display or if forced to skip
		if ($width < 5) {
			static::stdout("\r$prefix$info   ");
		} else {
			if ($percent < 0) {
				$percent = 0;
			} elseif ($percent > 1) {
				$percent = 1;
			}
			$bar = floor($percent * $width);
			$status = str_repeat("=", $bar);
			if ($bar < $width) {
				$status .= ">";
				$status .= str_repeat(" ", $width - $bar - 1);
			}
			static::stdout("\r$prefix" . "[$status] $info");
		}
		flush();
	}

	/**
	 * Ends a progress bar that has been started by [[startProgress()]].
	 *
	 * @param string|boolean $remove This can be `false` to leave the progress bar on screen and just print a newline.
	 * If set to `true`, the line of the progress bar will be cleared. This may also be a string to be displayed instead
	 * of the progress bar.
	 * @param bool $keepPrefix whether to keep the prefix that has been specified for the progressbar when progressbar
	 * gets removed. Defaults to true.
	 * @see startProgress
	 * @see updateProgress
	 */
	public static function endProgress($remove = false, $keepPrefix = true)
	{
		if ($remove === false) {
			static::stdout(PHP_EOL);
		} else {
			if (static::streamSupportsAnsiColors(STDOUT)) {
				static::clearLine();
			}
			static::stdout("\r" . ($keepPrefix ? self::$_progressPrefix : '') . (is_string($remove) ? $remove : ''));
		}
		flush();

		self::$_progressStart = null;
		self::$_progressWidth = null;
		self::$_progressPrefix = '';
	}
}