<?php 

$actions = [];
class Action {
	private $function_name;
	private $no_of_args;
	private $args_type;
	
	public function setFunctionName(string $s)  { $this->function_name = $s; return $this; }
	public function setArgumentsTypes(array $a) { $this->args_type = $a; $this->no_of_args = count($a); return $this; }
	public function getExpectedNoOfArguments()  { return $this->no_of_args; }
	public function getFunctionName()           { return $this->function_name; }
}
function registerAction(Action $a) { global $actions; $actions[$a->getFunctionName()] = $a; return true;}
// Register all actions available
require_once __DIR__."/actions/index.php";

function ExpandFetcherCommands(string $text) {
	global $actions;

	// Make it recursive, while you have parenthesis
	while(preg_match("/\(([^()]+)\)/",$text, $matches)) 
		$text = str_replace($matches[0],ExpandFetcherCommands($matches[1]),$text);


	$function_name_regex_format = "@([a-zA-Z_][a-zA-Z0-9_]+)";
	$arguments_regex_format = "([\w:\/\.-]+)";


	if (preg_match("/$function_name_regex_format( |$)/",$text,$matches)) {
		$function_name = $matches[1];

		if (	!isset($actions[$function_name]) ||
			!function_exists($function_name )) return "[[ Action $function_name not available. ]]";

		$action = $actions[$function_name];

		// Fetch the arguments
		$reg_exp = array_fill(0,$action->getExpectedNoOfArguments(),"([\w:\/\.-]+)");
		array_unshift($reg_exp, $function_name_regex_format);
			
		if (!preg_match("/".implode(" ",$reg_exp)."/",$text,$matches))
			return "[[ Action $function_name was passed with wrong number of arguemnts. Expected: ".$a->getExpectedNoOfArguments()." ]]";

		$full_action_requested_string = $matches[0];
		
		array_shift($matches); // Clip the first whole-string result
		array_shift($matches); // Clip the function name
		$arguments = $matches;
		$actionResult = call_user_func_array($function_name, $arguments);
			
		$text = str_replace($full_action_requested_string,$actionResult,$text);
	}

	return $text;

}