How to make a command that only excecuted when you step on certain block?

The title of this thread has self-explanatory. I am making a city roleplay server and I need a plugin that the command can only execute- when you step on a certain block, its for robbery plugin so the player can only use /startrob when they step on the bank floor (example gold block)

 

PHP:

// onCommand
$block = $player->getLevel()->getBlock($player->subtract(0, 1, 0));
if($block->getId() !== Block::GOLD_BLOCK) { // I'm not sure if it's golden or just gold
       $player->sendMessage("You may not execute this command here.");
       return;
}


 

Don't forget to make sure the player is on the bank's region! Otherwise players can just create gold blocks and defeat the system.
Example:

PHP:

$x = [100, 200];
$y = [20, 50];
$z = [100, 200];
$minY = min($y);
$minZ = min($z);
$maxX = max($x);
$maxY = max($y);
$maxZ = max($z);
$pos = $player->getPosition();
if(
    $pos->x >= $minX and $pos->x <= $maxX and
    $pos->y >= $minY and $pos->y <= $maxY and
    $pos->z >= $minZ and $pos->z <= $maxZ
){
 // Player is inside the region
}

 

A very nice addition! Yes. This is definitely necessary @AmalCraft

 

Btw that already had a plugin on poggit!
https://poggit.pmmp.io/p/StepCommand/1.0.3

 

If you haven't noticed, this was written on the development section. not the plugin request sections.