Added getInput() method for basic async input

examples/input.php

@@ -0,0 +1,31 @@
+<?php
+/*
+ *  This example demonstrates how to use events to catch commands that
+ *  have not been handled by any context or builtin.
+ *
+ */
+
+require_once __DIR__."/../vendor/autoload.php";
+
+use NoccyLabs\Shell\Shell;
+use NoccyLabs\Shell\Style;
+use NoccyLabs\Shell\Context;
+
+$myShell = new Shell();
+
+// Set the initial prompt, not really needed.
+$myShell->setPrompt("test>");
+
+// Create an anonymous context and add a command
+$ctx = $myShell->createContext("root");
+$ctx->addCommand("hello", function () use ($myShell) {
+    $myShell->getInput("What is your name?", function ($name) use ($myShell) {
+        echo "Hello, {$name}\n";
+        $myShell->getInput("Who is your daddy and what does he do?", function ($daddy) {
+            echo "{$daddy}? Oookay...\n";
+        });
+    });
+});
+
+// Run the shell
+$myShell->run();

lib/Shell.php

@@ -54,6 +54,18 @@ class Shell
      * @var Style The style applied to the input text
      */
     protected $input_style = null;
+    /**
+     * @var callable The callback to pass the input on to
+     */
+    protected $input_callback = null;
+    /**
+     * @var string Question prompt for getInput()
+     */
+    protected $input_prompt = null;
+    /**
+     * @var string The prompt before changing to $input_prompt
+     */
+    protected $input_last_prompt = null;
 
     /**
      * Constructor
@@ -532,6 +544,31 @@ class Shell
         return $event;
     }
 
+    public function getInput($prompt, callable $callback)
+    {
+        $this->addListener(Shell::EVT_UPDATE_PROMPT, [ $this, "onInputPrompt" ], $prompt);
+        $this->addListener(Shell::EVT_BEFORE_COMMAND, [ $this, "onInputHandler" ], $this->prompt, $callback);
+    }
+    
+    public function onInputPrompt(Event $e, $prompt)
+    {
+        $this->setPrompt($prompt);
+        $e->stopPropagation();
+        $this->removeListener(Shell::EVT_UPDATE_PROMPT, [ $this, "onInputPrompt" ], $prompt);
+    }
+    
+    public function onInputHandler(Event $e, $last_prompt, $callback)
+    {
+        // Restore the prompt
+        $this->setPrompt($last_prompt);
+        // Remove the listeners and compose the result string
+        $this->removeListener(Shell::EVT_BEFORE_COMMAND, [ $this, "onInputHandler" ], $last_prompt, $callback);
+        $input = trim($e->command." ".join(" ",$e->args));
+        $e->stopPropagation();
+        // Call the callback
+        call_user_func($callback, $input);
+    }
+
     /**
      * Stop the shell; calling this method will cause the main run() to return.
      *