Complete chapter 3

kilo

@@ -5,18 +5,23 @@ namespace Kilo;
 
 require_once __DIR__ . '/src/constants.php';
 require_once __DIR__ . '/src/functions.php';
-require_once __DIR__ . '/src/editor.php';
+require_once __DIR__ . '/src/Editor.php';
 
 function main(): int
 {
+	global $ffi;
+
 	enableRawMode();
 
-	$editor = new Editor();
+	// ob_start();
+	$editor = new Editor($ffi);
 
 	// Input Loop
 	while (true)
 	{
+		$editor->refreshScreen();
 		$editor->processKeypress();
+		// ob_flush();
 	}
 
 	return 0;

src/Editor.php

@@ -0,0 +1,277 @@
+<?php declare(strict_types=1);
+
+namespace Kilo;
+
+use FFI;
+
+class Key {
+	public const ARROW_LEFT = 'a';
+	public const ARROW_RIGHT = 'd';
+	public const ARROW_UP = 'w';
+	public const ARROW_DOWN = 's';
+	public const DEL_KEY = 'DEL';
+	public const HOME_KEY = 'HOME';
+	public const END_KEY = 'END';
+	public const PAGE_UP = 'PAGE_UP';
+	public const PAGE_DOWN = 'PAGE_DOWN';
+}
+
+class Editor {
+	private FFI $ffi;
+
+	protected int $cursorx = 0;
+	protected int $cursory = 0;
+	protected int $screenRows = 0;
+	protected int $screenCols = 0;
+	protected string $ab = '';
+
+	public function __construct($ffi)
+	{
+		$this->ffi = $ffi;
+
+		if ( ! $this->getWindowSize())
+		{
+			die('Failed to get screen size');
+		}
+	}
+
+	// ------------------------------------------------------------------------
+	// ! Terminal
+	// ------------------------------------------------------------------------
+	protected function readKey(): string
+	{
+		$c = read_stdin(1);
+
+		if ($c === '\x1b')
+		{
+			$seq = read_stdin();
+
+			if (strpos($seq, '[') === 0)
+			{
+				if ((int)$seq[1] >= 0 && (int)$seq[1] <= 9)
+				{
+					if (strpos($seq, '~') === 2)
+					{
+						switch($seq[1])
+						{
+							case '1': return Key::HOME_KEY;
+							case '3': return Key::DEL_KEY;
+							case '4': return Key::END_KEY;
+							case '5': return Key::PAGE_UP;
+							case '6': return Key::PAGE_DOWN;
+							case '7': return Key::HOME_KEY;
+							case '8': return Key::END_KEY;
+						}
+					}
+				}
+				else
+				{
+					switch($seq[1])
+					{
+						case 'A': return Key::ARROW_UP;
+						case 'B': return Key::ARROW_DOWN;
+						case 'C': return Key::ARROW_RIGHT;
+						case 'D': return Key::ARROW_LEFT;
+						case 'H': return Key::HOME_KEY;
+						case 'F': return Key::END_KEY;
+					}
+				}
+			}
+			else if (strpos($seq, 'O') === 0)
+			{
+				switch($seq[1])
+				{
+					case 'H': return Key::HOME_KEY;
+					case 'F': return Key::END_KEY;
+				}
+			}
+
+			return '\x1b';
+		}
+
+		return $c;
+	}
+
+	/**
+	 * @TODO fix
+	 */
+	private function getCursorPosition(): bool
+	{
+		write_stdout("\x1b[999C\x1b[999B");
+		write_stdout("\x1b[6n");
+
+		$buffer = read_stdout(32);
+
+		$rows = 0;
+		$cols = 0;
+
+		$res = sscanf($buffer, '\x1b[%d;%dR', $rows, $cols);
+
+		if ($res === -1 || $buffer[0] !== '\x1b' || $buffer[1] !== '[')
+		{
+			die('Failed to get screen size');
+			return false;
+		}
+
+		$this->screenRows = $rows;
+		$this->screenCols = $cols;
+
+		return true;
+	}
+
+	private function getWindowSize(): bool
+	{
+		$ws = $this->ffi->new('struct winsize');
+		$res = $this->ffi->ioctl(STDOUT_FILENO, TIOCGWINSZ, FFI::addr($ws));
+
+		if ($res === -1 || $ws->ws_col === 0)
+		{
+			return $this->getCursorPosition();
+		}
+
+		$this->screenCols = $ws->ws_col;
+		$this->screenRows = $ws->ws_row;
+
+		return true;
+	}
+
+	// ------------------------------------------------------------------------
+	// ! Output
+	// ------------------------------------------------------------------------
+
+	protected function drawRows(): void
+	{
+		for ($y = 0; $y < $this->screenRows; $y++)
+		{
+			if ($y === ($this->screenRows / 3))
+			{
+				$welcome = sprintf('PHP Kilo editor -- version %s', KILO_VERSION);
+				$welcomelen = strlen($welcome);
+				if ($welcomelen > $this->screenCols)
+				{
+					$welcomelen = $this->screenCols;
+				}
+
+				$padding = ($this->screenCols - $welcomelen) / 2;
+				if ($padding)
+				{
+					$this->ab .= '~';
+					$padding--;
+				}
+				while ($padding--)
+				{
+					$this->ab .= ' ';
+				}
+
+				$this->ab .= substr($welcome, 0, $welcomelen);
+
+			}
+			else
+			{
+				$this->ab .= '~';
+			}
+
+			$this->ab .= "\x1b[K"; // Clear the current line
+			if ($y < $this->screenRows - 1)
+			{
+				$this->ab .= "\r\n";
+			}
+		}
+	}
+
+	public function refreshScreen(): void
+	{
+		$this->ab = '';
+
+		$this->ab .= "\x1b[?25l"; // Hide the cursor
+		$this->ab .= "\x1b[H"; // Reposition cursor to top-left
+
+		$this->drawRows();
+
+		// Specify the current cursor position
+		$this->ab .= sprintf("\x1b[%d;%dH", $this->cursory + 1, $this->cursorx + 1);
+
+		$this->ab .= "\x1b[?25h"; // Show the cursor
+
+		write_stdout($this->ab);
+	}
+
+	// ------------------------------------------------------------------------
+	// ! Input
+	// ------------------------------------------------------------------------
+
+	protected function moveCursor(string $key): void
+	{
+		switch ($key)
+		{
+			case Key::ARROW_LEFT:
+				if ($this->cursorx !== 0)
+				{
+					$this->cursorx--;
+				}
+			break;
+
+			case Key::ARROW_RIGHT:
+				if ($this->cursorx !== $this->screenCols - 1)
+				{
+					$this->cursorx++;
+				}
+			break;
+
+			case Key::ARROW_UP:
+				if ($this->cursory !== 0)
+				{
+					$this->cursory--;
+				}
+			break;
+
+			case Key::ARROW_DOWN:
+				if ($this->cursory !== $this->screenRows - 1)
+				{
+					$this->cursory++;
+				}
+			break;
+		}
+	}
+
+	public function processKeypress(): string
+	{
+		$c = $this->readKey();
+		switch($c)
+		{
+			case chr(ctrl_key('q')):
+				write_stdout("\x1b[2J"); // Clear the screen
+				write_stdout("\x1b[H"); // Reposition cursor to top-left
+				exit(0);
+			break;
+
+			case Key::HOME_KEY:
+				$this->cursorx = 0;
+			break;
+
+			case Key::END_KEY:
+				$this->cursorx = $this->screenCols - 1;
+			break;
+
+			case Key::PAGE_UP:
+			case Key::PAGE_DOWN:
+			{
+				$times = $this->screenRows;
+				while ($times--)
+				{
+					$this->moveCursor($c === Key::PAGE_UP ? Key::ARROW_UP : Key::ARROW_DOWN);
+				}
+			}
+			break;
+
+			case Key::ARROW_UP:
+			case Key::ARROW_DOWN:
+			case Key::ARROW_LEFT:
+			case Key::ARROW_RIGHT:
+				$this->moveCursor($c);
+			break;
+		}
+
+		return $c;
+	}
+}

src/constants.php

@@ -2,6 +2,8 @@
 
 namespace Kilo;
 
+define('KILO_VERSION', '0.0.1');
+
 define('STDIN_FILENO', 0);
 define('STDOUT_FILENO', 1);
 define('STDERR_FILENO', 2);
@@ -130,3 +132,8 @@ define('VMIN', 16);		/* Minimum number of bytes read at once [!ICANON].  */
 define('VTIME', 17);		/* Time-out value (tenths of a second) [!ICANON].  */
 define('VSTATUS', 18);		/* Status character [ICANON].  */
 define('NCCS', 20);		/* Value duplicated in <hurd/tioctl.defs>.  */
+
+// -----------------------------------------------------------------------------
+// ! IOCTL constants
+// -----------------------------------------------------------------------------
+define('TIOCGWINSZ', 0x5413);

src/editor.php

@@ -1,27 +0,0 @@
-<?php declare(strict_types=1);
-
-namespace Kilo;
-
-class Editor {
-	public function __construct()
-	{
-
-	}
-
-	public function processKeypress(): void
-	{
-		$c = $this->readKey();
-
-		switch($c)
-		{
-			case chr(ctrl_key('q')):
-				exit(0);
-			break;
-		}
-	}
-
-	protected function readKey(): string
-	{
-		return read_stdin(1);
-	}
-}

src/ffi.h

@@ -55,3 +55,16 @@ void cfmakeraw (struct termios *termios_p);
 //! <ctype.h>
 // -----------------------------------------------------------------------------
 int iscntrl (int);
+
+ssize_t read(int, void *, size_t);
+
+// -----------------------------------------------------------------------------
+//! <sys/ioctl.h>
+// -----------------------------------------------------------------------------
+struct winsize {
+	unsigned short ws_row;
+	unsigned short ws_col;
+	unsigned short ws_xpixel;
+	unsigned short ws_ypixel;
+};
+int ioctl (int, int, ...);

src/functions.php

@@ -15,7 +15,11 @@ function enableRawMode(): void
 	register_shutdown_function('Kilo\\disableRawMode');
 
 	// Populate the original terminal settings
-	$ffi->tcgetattr(STDIN_FILENO, FFI::addr($original_termios));
+	$res = $ffi->tcgetattr(STDIN_FILENO, FFI::addr($original_termios));
+	if ($res === -1)
+	{
+		die('tcgetattr');
+	}
 
 	$termios = $ffi->new('struct termios');
 	$termios->c_iflag &= ~(BRKINT | ICRNL | INPCK | ISTRIP | IXON);
@@ -26,7 +30,11 @@ function enableRawMode(): void
 	$termios->c_cc[VTIME] = 1;
 
 	// Turn on raw mode
-	$ffi->tcsetattr(STDIN_FILENO, TCSAFLUSH, FFI::addr($termios));
+	$res = $ffi->tcsetattr(STDIN_FILENO, TCSAFLUSH, FFI::addr($termios));
+	if ($res === -1)
+	{
+		die('tcsetattr');
+	}
 }
 
 function disableRawMode(): void
@@ -34,7 +42,12 @@ function disableRawMode(): void
 	global $ffi;
 	global $original_termios;
 
-	$ffi->tcsetattr(STDIN_FILENO, TCSAFLUSH, FFI::addr($original_termios));
+	$res = $ffi->tcsetattr(STDIN_FILENO, TCSAFLUSH, FFI::addr($original_termios));
+
+	if ($res === -1)
+	{
+		die('tcsetattr');
+	}
 }
 
 function read_stdin(int $len = 128): string
@@ -48,6 +61,29 @@ function read_stdin(int $len = 128): string
 	return $input;
 }
 
+function write_stdout(string $str, int $len = NULL): int
+{
+	$handle = fopen('php://stdout', 'ab');
+	$res = (is_int($len))
+		? fwrite($handle, $str, $len)
+		: fwrite($handle, $str);
+
+	fclose($handle);
+
+	return $res;
+}
+
+function read_stdout(int $len = 128): string
+{
+	$handle = fopen('php://stdout', 'rb');
+	$input = fread($handle, $len);
+
+	$input = rtrim($input);
+	fclose($handle);
+
+	return $input;
+}
+
 function ctrl_key(string $char): int
 {
 	return ord($char) & 0x1f;