Initial commit

2024-02-27 02:08:29 +01:00
commit c92c40b45a
7 changed files with 889 additions and 0 deletions
--- a/src/Shell.php
+++ b/src/Shell.php
@ -0,0 +1,180 @@
+<?php
+
+namespace NoccyLabs\React\Shell;
+
+use Evenement\EventEmitterInterface;
+use Evenement\EventEmitterTrait;
+use React\EventLoop\Loop;
+use React\Stream\ReadableResourceStream;
+use React\Stream\ReadableStreamInterface;
+use React\Stream\WritableResourceStream;
+use React\Stream\WritableStreamInterface;
+
+class Shell implements WritableStreamInterface, EventEmitterInterface
+{
+    use EventEmitterTrait;
+
+    private ReadableStreamInterface $istream;
+
+    private WritableStreamInterface $ostream;
+
+    private string $oldStty;
+
+    private bool $isPrompting = false;
+
+    private string $buffer = '';
+
+    private int $cursorPos = 0;
+
+    private int $termWidth = 0;
+
+    private int $scrollOffset = 0;
+
+    private string $prompt = '';
+
+    private int $promptWidth = 0;
+
+    public function __construct(?ReadableStreamInterface $input=null, ?WritableStreamInterface $output=null)
+    {
+        $this->istream = $input ?? new ReadableResourceStream(STDIN);
+        $this->ostream = $output ?? new WritableResourceStream(STDOUT);
+
+        $this->istream->on('data', $this->handleInput(...));
+        
+        Loop::futureTick($this->redrawPrompt(...));
+
+        // Save terminal settings and disable inupt buffering
+        $this->oldStty = exec("stty -g");
+        exec("stty -icanon min 1 time 0 -echo");
+    }
+
+    public function  __destruct()
+    {
+        // Restore the terminal to regular buffered mode
+        exec("stty {$this->oldStty}");
+    }
+
+    public function setPrompt(string $prompt): void
+    {
+        $this->prompt = $prompt;
+        $this->promptWidth = mb_strlen($this->prompt);        
+    }
+
+    private function handleInput($v) {
+
+        switch ($v) {
+
+            case "\x03": 
+                exit(0);
+
+            case "\n":
+                $buffer = str_getcsv($this->buffer, " ");
+                $this->buffer = '';
+                $this->cursorPos = 0;
+                $this->scrollOffset = 0;
+                $this->emit('input', [ $buffer ]);
+                break;
+
+            case "\x7F": // backspace
+                if ($this->cursorPos < 1) return;
+                $this->buffer = mb_substr($this->buffer, 0, $this->cursorPos - 1) .
+                                mb_substr($this->buffer, $this->cursorPos);
+                $this->cursorPos--;
+                break;
+
+            case "\e[3~": // delete
+                $this->buffer = mb_substr($this->buffer, 0, $this->cursorPos) .
+                                mb_substr($this->buffer, $this->cursorPos + 1);
+                break;
+    
+            case "\e[A": // up
+            case "\e[B": // down
+                break;
+
+            case "\e[H": // home
+            case "\e[F": // end
+                    break;
+        
+            case "\e[D": // left
+                if ($this->cursorPos < 1) return;
+                $this->cursorPos--;                
+                break;
+
+            case "\e[C": // right
+                if ($this->cursorPos >= mb_strlen($this->buffer)) return;
+                $this->cursorPos++;
+                break;
+
+            default:
+                if (mb_strlen($v) == 1 && ord($v) >= 32) {
+                    $this->buffer = mb_substr($this->buffer, 0, $this->cursorPos) .
+                                    $v . 
+                                    mb_substr($this->buffer, $this->cursorPos);
+                    $this->cursorPos++;
+                } else {
+                    $this->ostream->write("\e[7m".substr($v,2)."\e[27m");
+                    return;
+                }
+        }
+        $this->updatePrompt();
+    }
+
+
+    public function write($data)
+    {
+        $this->hidePrompt();
+        $this->ostream->write($data);
+        $this->redrawPrompt();
+        return true;
+    }
+
+    public function isWritable()
+    {
+        return true;
+    }
+
+    public function end($data = null)
+    {
+        // NOP
+    }
+
+    public function close()
+    {
+        // NOP
+    }
+
+
+
+    public function hidePrompt(): void
+    {
+        if (!$this->isPrompting) return;
+
+        $this->isPrompting = false;
+
+        $this->ostream->write("\r\e[K");
+    }
+
+    public function redrawPrompt(): void
+    {
+        $prompt = $this->emit("prompt");
+
+        $this->termWidth = intval(exec("tput cols"));
+        $this->isPrompting = true;
+
+        $this->updatePrompt();
+    }
+
+    private function updatePrompt(): void
+    {
+        if (!$this->isPrompting) return;
+
+        $pos = $this->promptWidth + $this->cursorPos - $this->scrollOffset + 1;
+
+        $obuf = "\r" . "\e[1m" . $this->prompt . "\e[22m";
+        $ostr = mb_substr($this->buffer, $this->scrollOffset) . " ";
+        $ostr = mb_substr($ostr, 0, $this->termWidth - $this->promptWidth);
+        $obuf .= $ostr . "\e[K\e[" . $pos . "G";
+
+        $this->ostream->write($obuf);
+    }
+}