Finish chapter 4, drawing issues exist, at least in tmux

kilo

@@ -21,6 +21,7 @@ function main(int $argc, array $argv): int
 		$editor->open($argv[1]);
 	}
 
+	$editor->setStatusMessage("HELP: Ctrl-Q = quit");
 
 	// Input Loop
 	while (true)

src/Editor.php

@@ -4,11 +4,28 @@ namespace Kilo;
 
 use FFI;
 
+trait MagicProperties {
+	abstract public function __get(string $name);
+
+	public function __set(string $name, $value)
+	{
+		if (property_exists($this, $name))
+		{
+			$this->$name = $value;
+		}
+	}
+
+	public function __isset(string $name): bool
+	{
+		return isset($this->$name);
+	}
+}
+
 class Key {
-	public const ARROW_LEFT = 'a';
+	public const ARROW_LEFT = 'ARROW_LEFT';
-	public const ARROW_RIGHT = 'd';
+	public const ARROW_RIGHT = 'ARROW_RIGHT';
-	public const ARROW_UP = 'w';
+	public const ARROW_UP = 'ARROW_UP';
-	public const ARROW_DOWN = 's';
+	public const ARROW_DOWN = 'ARROW_DOWN';
 	public const DEL_KEY = 'DEL';
 	public const HOME_KEY = 'HOME';
 	public const END_KEY = 'END';
@@ -16,8 +33,15 @@ class Key {
 	public const PAGE_DOWN = 'PAGE_DOWN';
 }
 
+/**
+ * @property-read int size
+ * @property-read int rsize
+ */
 class Row {
-	public string $chars;
+	use MagicProperties;
+
+	public string $chars = '';
+	public string $render = '';
 
 	public static function new(string $chars): self
 	{
@@ -28,24 +52,49 @@ class Row {
 	{
 		$this->chars = $chars;
 	}
+
+	public function __get(string $name)
+	{
+		switch ($name)
+		{
+			case 'size':
+				return strlen($this->chars);
+
+			case 'rsize':
+				return strlen($this->render);
+
+			default:
+				return NULL;
+		}
+	}
 }
 
+/**
+ * @property-read int numRows
+ */
 class Editor {
-	private FFI $ffi;
+	use MagicProperties;
 
-	protected int $cursorx = 0;
+	private FFI $ffi;
-	protected int $cursory = 0;
+	private string $ab = '';
-	protected int $rowoff = 0;
+
-	protected int $coloff = 0;
+	protected int $cursorX = 0;
+	protected int $cursorY = 0;
+	protected int $renderX = 0;
+	protected int $rowOffset = 0;
+	protected int $colOffset = 0;
 	protected int $screenRows = 0;
 	protected int $screenCols = 0;
-	protected string $ab = '';
 
 	/**
 	 * Array of Row objects
 	 */
 	protected array $rows = [];
 
+	protected string $filename = '';
+	protected string $statusMsg = '';
+	protected int $statusMsgTime;
+
 	public static function new(FFI $ffi): Editor
 	{
 		return new self($ffi);
@@ -54,11 +103,26 @@ class Editor {
 	private function __construct($ffi)
 	{
 		$this->ffi = $ffi;
+		$this->statusMsgTime = time();
 
 		if ( ! $this->getWindowSize())
 		{
 			die('Failed to get screen size');
 		}
+
+		$this->screenRows -= 2;
+
+		// print_r($this); die();
+	}
+
+	public function __get(string $name)
+	{
+		if ($name === 'numRows')
+		{
+			return count($this->rows);
+		}
+
+		return NULL;
 	}
 
 	// ------------------------------------------------------------------------
@@ -72,27 +136,38 @@ class Editor {
 		{
 			$seq = read_stdin();
 
+			if (strlen($seq) < 3)
+			{
+				return '\x1b';
+			}
+
 			if (strpos($seq, '[') === 0)
 			{
-				if ((int)$seq[1] >= 0 && (int)$seq[1] <= 9)
+				$seq1 = (int)$seq[1];
+
+				if ($seq1 >= 0 && $seq1 <= 9)
 				{
 					if (strpos($seq, '~') === 2)
 					{
-						switch($seq[1])
+						switch ($seq[1])
 						{
-							case '1': return Key::HOME_KEY;
+							case '1':
+							case '7':
+								return Key::HOME_KEY;
+
+							case '4':
+							case '8':
+								return Key::END_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($seq[1])
+					switch ($seq[1])
 					{
 						case 'A': return Key::ARROW_UP;
 						case 'B': return Key::ARROW_DOWN;
@@ -105,7 +180,7 @@ class Editor {
 			}
 			else if (strpos($seq, 'O') === 0)
 			{
-				switch($seq[1])
+				switch ($seq[1])
 				{
 					case 'H': return Key::HOME_KEY;
 					case 'F': return Key::END_KEY;
@@ -126,23 +201,22 @@ class Editor {
 		write_stdout("\x1b[999C\x1b[999B");
 		write_stdout("\x1b[6n");
 
-		$buffer = read_stdout(32);
-
 		$rows = 0;
 		$cols = 0;
 
+		$buffer = read_stdout();
+
 		$res = sscanf($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;
+		return TRUE;
 	}
 
 	private function getWindowSize(): bool
@@ -165,9 +239,47 @@ class Editor {
 	// ! Row Operations
 	// ------------------------------------------------------------------------
 
+	protected function rowCxToRx(Row $row, int $cx): int
+	{
+		$rx = 0;
+		for ($i = 0; $i < $cx; $i++)
+		{
+			if ($row->chars[$i] === "\t")
+			{
+				$rx += (KILO_TAB_STOP - 1) - ($rx % KILO_TAB_STOP);
+			}
+			$rx++;
+		}
+
+		return $rx;
+	}
+
+	protected function updateRow(Row $row): void
+	{
+		$idx = 0;
+
+		for ($i = 0; $i < $row->size; $i++)
+		{
+			if ($row->chars[$i] === "\t")
+			{
+				$row->render[$idx++] = ' ';
+				while ($idx % KILO_TAB_STOP !== 0)
+				{
+					$row->render[$idx++] = ' ';
+				}
+			}
+			else
+			{
+				$row->render[$idx++] = $row->chars[$i];
+			}
+		}
+	}
+
 	protected function appendRow(string $s): void
 	{
-		$this->rows[] = Row::new($s);
+		$at = $this->numRows;
+		$this->rows[$at] = Row::new($s);
+		$this->updateRow($this->rows[$at]);
 	}
 
 	// ------------------------------------------------------------------------
@@ -176,6 +288,10 @@ class Editor {
 
 	public function open(string $filename): void
 	{
+		// Copy filename for display
+		$this->filename = $filename;
+
+		// Determine the full path to the file
 		$baseFile = basename($filename);
 		$basePath = str_replace($baseFile, '', $filename);
 		$path = (is_dir($basePath)) ? $basePath : getcwd();
@@ -183,6 +299,7 @@ class Editor {
 		$fullname = $path . '/' . $baseFile;
 
 
+		// #TODO gracefully handle issues with loading a file
 		$handle = fopen($fullname, 'rb');
 
 		while (($line = fgets($handle)) !== FALSE)
@@ -199,14 +316,30 @@ class Editor {
 
 	protected function scroll(): void
 	{
-		if ($this->cursory < $this->rowoff)
+		$this->renderX = 0;
+		if ($this->cursorY < $this->numRows)
 		{
-			$this->rowoff = $this->cursory;
+			$this->renderX = $this->rowCxToRx($this->rows[$this->cursorY], $this->cursorX);
 		}
 
-		if ($this->cursory >= $this->rowoff + $this->screenRows)
+		// Vertical Scrolling
+		if ($this->cursorY < $this->rowOffset)
 		{
-			$this->rowoff = $this->cursory - $this->screenRows + 1;
+			$this->rowOffset = $this->cursorY;
+		}
+		if ($this->cursorY >= $this->rowOffset + $this->screenRows)
+		{
+			$this->rowOffset = $this->cursorY - $this->screenRows + 1;
+		}
+
+		// Horizontal Scrolling
+		if ($this->renderX < $this->colOffset)
+		{
+			$this->colOffset = $this->renderX;
+		}
+		if ($this->renderX >= $this->colOffset + $this->screenCols)
+		{
+			$this->colOffset = $this->renderX - $this->screenCols + 1;
 		}
 	}
 
@@ -214,10 +347,10 @@ class Editor {
 	{
 		for ($y = 0; $y < $this->screenRows; $y++)
 		{
-			$filerow = $y + $this->rowoff;
+			$filerow = $y + $this->rowOffset;
 			if ($filerow >= count($this->rows))
 			{
-				if (count($this->rows) === 0 && $y === $this->screenRows / 3)
+				if ($this->numRows === 0 && $y === $this->screenRows / 3)
 				{
 					$welcome = sprintf('PHP Kilo editor -- version %s', KILO_VERSION);
 					$welcomelen = strlen($welcome);
@@ -227,7 +360,7 @@ class Editor {
 					}
 
 					$padding = ($this->screenCols - $welcomelen) / 2;
-					if ($padding)
+					if ($padding > 0)
 					{
 						$this->ab .= '~';
 						$padding--;
@@ -246,7 +379,7 @@ class Editor {
 			}
 			else
 			{
-				$len = strlen($this->rows[$filerow]->chars) - $this->coloff;
+				$len = $this->rows[$filerow]->rsize - $this->colOffset;
 				if ($len < 0)
 				{
 					$len = 0;
@@ -256,14 +389,55 @@ class Editor {
 					$len = $this->screenCols;
 				}
 
-				$this->ab .= substr($this->rows[$filerow]->chars, $this->coloff, $len);
+				$this->ab .= substr($this->rows[$filerow]->render, $this->colOffset, $len);
 			}
 
 			$this->ab .= "\x1b[K"; // Clear the current line
-			if ($y < $this->screenRows - 1)
+			$this->ab .= "\r\n";
+		}
+	}
+
+	protected function drawStatusBar(): void
+	{
+		$this->ab .= "\x1b[7m";
+
+		$statusFilename = $this->filename !== '' ? $this->filename : '[No Name]';
+		$status = sprintf("%.20s - %d lines", $statusFilename, count($this->rows));
+		$rstatus = sprintf("%d/%d", $this->cursorY + 1, count($this->rows));
+		$len = strlen($status);
+		$rlen = strlen($rstatus);
+		if ($len > $this->screenCols)
+		{
+			$len = $this->screenCols;
+		}
+		$this->ab .= substr($status, 0, $len);
+		while ($len < $this->screenCols)
+		{
+			if ($this->screenCols - $len === $rlen)
 			{
-				$this->ab .= "\r\n";
+				$this->ab .= substr($rstatus, 0, $rlen);
+				break;
 			}
+
+			$this->ab .= ' ';
+			$len++;
+		}
+		$this->ab .= "\x1b[m";
+		$this->ab .= "\r\n";
+	}
+
+	protected function drawMessageBar(): void
+	{
+		$this->ab .= "\x1b[K";
+		$len = strlen($this->statusMsg);
+		if ($len > $this->screenCols)
+		{
+			$len = $this->screenCols;
+		}
+
+		if ($len > 0 && (time() - $this->statusMsgTime) < 5)
+		{
+			$this->ab .= substr($this->statusMsg, 0, $len);
 		}
 	}
 
@@ -277,13 +451,26 @@ class Editor {
 		$this->ab .= "\x1b[H"; // Reposition cursor to top-left
 
 		$this->drawRows();
+		$this->drawStatusBar();
+		$this->drawMessageBar();
 
 		// Specify the current cursor position
-		$this->ab .= sprintf("\x1b[%d;%dH", ($this->cursory - $this->rowoff) + 1, $this->cursorx + 1);
+		$this->ab .= sprintf("\x1b[%d;%dH",
+			($this->cursorY - $this->rowOffset) + 1,
+			($this->renderX - $this->colOffset) + 1
+		);
 
 		$this->ab .= "\x1b[?25h"; // Show the cursor
 
-		write_stdout($this->ab);
+		echo $this->ab;
+	}
+
+	public function setStatusMessage(string $fmt, ...$args): void
+	{
+		$this->statusMsg = (count($args) > 0)
+			? sprintf($fmt, ...$args)
+			: $fmt;
+		$this->statusMsgTime = time();
 	}
 
 	// ------------------------------------------------------------------------
@@ -292,55 +479,75 @@ class Editor {
 
 	protected function moveCursor(string $key): void
 	{
+		$row = ($this->cursorY >= $this->numRows)
+			? NULL
+			: $this->rows[$this->cursorY];
+
 		switch ($key)
 		{
 			case Key::ARROW_LEFT:
-				if ($this->cursorx !== 0)
+				if ($this->cursorX !== 0)
 				{
-					$this->cursorx--;
+					$this->cursorX--;
+				}
+				else if ($this->cursorX > 0)
+				{
+					$this->cursorY--;
+					$this->cursorX = $this->rows[$this->cursorY]->size;
 				}
 			break;
 
 			case Key::ARROW_RIGHT:
-				if ($this->cursorx !== $this->screenCols - 1)
+				if ($row && $this->cursorX < $row->size)
 				{
-					$this->cursorx++;
+					$this->cursorX++;
+				}
+				else if ($row && $this->cursorX === $row->size)
+				{
+					$this->cursorY++;
+					$this->cursorX = 0;
 				}
 			break;
 
 			case Key::ARROW_UP:
-				if ($this->cursory !== 0)
+				if ($this->cursorY !== 0)
 				{
-					$this->cursory--;
+					$this->cursorY--;
 				}
 			break;
 
 			case Key::ARROW_DOWN:
-				if ($this->cursory < count($this->rows))
+				if ($this->cursorY < $this->numRows)
 				{
-					$this->cursory++;
+					$this->cursorY++;
 				}
 			break;
 		}
+
+		$row = ($this->cursorY >= $this->numRows)
+			? NULL
+			: $this->rows[$this->cursorY];
+		$rowlen = $row ? $row->size : 0;
+		if ($this->cursorX > $rowlen)
+		{
+			$this->cursorX = $rowlen;
+		}
 	}
 
 	public function processKeypress(): string
 	{
 		$c = $this->readKey();
-		switch($c)
+		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;
+				$this->cursorX = 0;
 			break;
 
 			case Key::END_KEY:
-				$this->cursorx = $this->screenCols - 1;
+				if ($this->cursorY < $this->numRows)
+				{
+					$this->cursorX = $this->rows[$this->cursorY]->size;
+				}
 			break;
 
 			case Key::PAGE_UP:
@@ -354,13 +561,33 @@ class Editor {
 			case Key::ARROW_RIGHT:
 				$this->moveCursor($c);
 			break;
+
+			case chr(ctrl_key('q')):
+				write_stdout("\x1b[2J"); // Clear the screen
+				write_stdout("\x1b[H"); // Reposition cursor to top-left
+				exit(0);
+			break;
 		}
 
 		return $c;
 	}
 
-	private function pageUpOrDown(string $c):void
+	private function pageUpOrDown(string $c): void
 	{
+		if ($c === Key::PAGE_UP)
+		{
+			$this->cursorY = $this->rowOffset;
+		}
+		else if ($c === Key::PAGE_DOWN)
+		{
+			$this->cursorY = $this->rowOffset + $this->screenRows - 1;
+			if ($this->cursorY > $this->numRows)
+			{
+				$this->cursorY = $this->numRows;
+
+			}
+		}
+
 		$times = $this->screenRows;
 		while ($times--)
 		{

src/constants.php

@@ -2,7 +2,15 @@
 
 namespace Kilo;
 
+// -----------------------------------------------------------------------------
+// ! App Constants
+// -----------------------------------------------------------------------------
 define('KILO_VERSION', '0.0.1');
+define('KILO_TAB_STOP', 4);
+
+// -----------------------------------------------------------------------------
+// ! Misc I/O constants
+// -----------------------------------------------------------------------------
 
 define('STDIN_FILENO', 0);
 define('STDOUT_FILENO', 1);