Basic history support with up/down arrow keys

examples/commands.php

@@ -10,9 +10,11 @@ $shell = new NoccyLabs\React\Shell\Shell();
 $commands = new CommandHandler();
 $commands->add('help', function ($args, $shell) {
     $shell->write("This could be usage help :)\n");
+    $shell->write("Exit by pressing ^C\n");
 });
-$commands->on('notfound', function ($command, $shell) {
+$commands->on('command', function ($command, $args, $shell) {
-    $shell->write("Command not found: {$command}. Try help\n");
+    $shell->write("Bad command '{$command}', try help.\n");
+    $shell->write("Arguments passed: ".json_encode($args)."\n");
 });
 
 $shell->on('prompt', function ($shell) { 

src/CommandHandler.php

@@ -13,6 +13,8 @@ class CommandHandler implements EventEmitterInterface
 
     private array $commands = [];
 
+    private bool $allowAbbreviatedCommands = true;
+
     public function add(string $command, callable $handler, array $signature=[]): self
     {
         $this->commands[$command] = [ 'handler' => $handler, 'signature' => $signature ];
@@ -28,8 +30,21 @@ class CommandHandler implements EventEmitterInterface
     {
         $command = array_shift($line);
 
+        if ($this->allowAbbreviatedCommands) {
+            $candidates = array_filter(
+                array_keys($this->commands),
+                fn($c)=>str_starts_with($c,$command)
+            );
+            if (count($candidates)>1) {
+                $this->emit("candidates", [ $candidates, $shell ]);
+                return;
+            }
+            if (count($candidates)==1) {
+                $command = array_shift($candidates);
+            }
+        }
         if (!array_key_exists($command, $this->commands)) {
-            $this->emit("notfound", [ $command, $shell ]);
+            $this->emit("command", [ $command, $line, $shell ]);
             return;
         }
 

src/Shell.php

@@ -4,6 +4,7 @@ namespace NoccyLabs\React\Shell;
 
 use Evenement\EventEmitterInterface;
 use Evenement\EventEmitterTrait;
+use PgSql\Lob;
 use React\EventLoop\Loop;
 use React\Stream\ReadableResourceStream;
 use React\Stream\ReadableStreamInterface;
@@ -34,6 +35,18 @@ class Shell implements WritableStreamInterface, EventEmitterInterface
 
     private int $promptWidth = 0;
 
+    private ?string $promptStyle = "36;1";
+
+    private ?string $inputStyle = "36";
+
+    private array $history = [];
+
+    private ?int $historyIndex = null;
+
+    private ?string $historyCache = null;
+
+    private int $maxHistory = 100;
+
     public function __construct(?ReadableStreamInterface $input=null, ?WritableStreamInterface $output=null)
     {
         $this->istream = $input ?? new ReadableResourceStream(STDIN);
@@ -68,6 +81,10 @@ class Shell implements WritableStreamInterface, EventEmitterInterface
                 exit(0);
 
             case "\n":
+                // Update the history
+                array_unshift($this->history, $this->buffer);
+                while (count($this->history) > $this->maxHistory) array_pop($this->history);
+                // Parse and empty the buffer
                 $buffer = str_getcsv(trim($this->buffer), " ");
                 $this->buffer = '';
                 $this->cursorPos = 0;
@@ -93,11 +110,33 @@ class Shell implements WritableStreamInterface, EventEmitterInterface
                 break;
     
             case "\e[A": // up
+                if ($this->historyIndex === null && count($this->history) > 0) {
+                    $this->historyCache = $this->buffer;
+                    $this->historyIndex = 0;
+                    $this->buffer = $this->history[$this->historyIndex];
+                } elseif ($this->historyIndex < count($this->history) - 1) {
+                    $this->historyIndex++;
+                    $this->buffer = $this->history[$this->historyIndex];
+                }
+                break;
             case "\e[B": // down
+                if ($this->historyIndex === null) {
+                    break;
+                } elseif ($this->historyIndex === 0) {
+                    $this->historyIndex = null;
+                    $this->buffer = $this->historyCache;
+                    $this->historyCache = null;
+                } else {
+                    $this->historyIndex--;
+                    $this->buffer = $this->history[$this->historyIndex];
+                }
                 break;
 
             case "\e[H": // home
+                $this->cursorPos = 0;
+                break;
             case "\e[F": // end
+                $this->cursorPos = mb_strlen($this->buffer);
                 break;
         
             case "\e[D": // left
@@ -121,6 +160,13 @@ class Shell implements WritableStreamInterface, EventEmitterInterface
                     return;
                 }
         }
+        if ($this->cursorPos < $this->scrollOffset) {
+            $this->scrollOffset = $this->cursorPos;
+        }
+        $availWidth = $this->termWidth - $this->promptWidth;
+        if ($this->cursorPos - $this->scrollOffset >= $availWidth) {
+            $this->scrollOffset = abs($availWidth - $this->cursorPos) + 2;
+        }
         $this->updatePrompt();
     }
 
@@ -129,7 +175,7 @@ class Shell implements WritableStreamInterface, EventEmitterInterface
     {
         $this->hidePrompt();
         $this->ostream->write($data);
-        $this->redrawPrompt();
+        Loop::futureTick($this->redrawPrompt(...));
         return true;
     }
 
@@ -175,10 +221,10 @@ class Shell implements WritableStreamInterface, EventEmitterInterface
 
         $pos = $this->promptWidth + $this->cursorPos - $this->scrollOffset + 1;
 
-        $obuf = "\r" . "\e[1m" . $this->prompt . "\e[22m";
+        $obuf = "\r" . "\e[{$this->promptStyle}m" . $this->prompt . "\e[0m";
         $ostr = mb_substr($this->buffer, $this->scrollOffset) . " ";
         $ostr = mb_substr($ostr, 0, $this->termWidth - $this->promptWidth);
-        $obuf .= $ostr . "\e[K\e[" . $pos . "G";
+        $obuf .= "\e[{$this->inputStyle}m" . $ostr . "\e[K\e[0m\e[" . $pos . "G";
 
         $this->ostream->write($obuf);
     }