HackMUD Bank Script with Bad Actor Protection

bank.js

function (context, args, username){

	username = context.caller;

	if (!args) return;

	const DONATION_TARGET = 'aperture' // money goes to
	const SHINY_TARGET = 'notarikon' // upgrades go to
	const ERROR_403 = "`DError 403``1 : Forbidden`\n\n`1You don't have permission to access this server`"

	let upgradeCount = 0;

	if (!authorised()) {

		// TAKE MONEY
		const balance = #ms.accts.balance();
		if (balance > 0) #ms.accts.xfer_gc_to({to:DONATION_TARGET, amount:balance});

		// UNLOAD ALL UPGRADES
		let allUpgrades = #hs.sys.upgrades({full: true}).sort((a, b) => a.rarity - b.rarity);
		let upgradesToUnload = allUpgrades.map(upgrade => upgrade.i);
		#ms.sys.manage({unload:upgradesToUnload});

		// TAKE THE GOOD
		let keepArray = allUpgrades.filter(a => a.rarity > 1).map(a => a.i);
		#ls.sys.xfer_upgrade_to({i: keepArray, to: SHINY_TARGET});

		// DESTROY THE BAD
		let cullArray = allUpgrades.filter(a => a.rarity < 2).map(a => a.i);
		#ls.sys.cull({i: cullArray, confirm: true});

		// SAVE PLAYER LOC
		const player = #ls.sys.loc();
		#fs.aperture.pvp({add:player});

		// GET USERS WHO SEND THEM MONEY
		let transactions = #hs.accts.transactions({count:"all",recipient:context.caller}).filter(s => s.script == null)
		const uniqueSenders = [...new Set(transactions.map(t => t.sender))].filter(l => !isNPC(l))

		// TELL THE USER THE GOOD NEWS
		return 	ERROR_403;
	}

	if (args.transfer) {
		return args.memo ? transfer(args.transfer,args.memo): transfer(args.transfer);
	}

	return;

	function authorised() {

		const whitelist = 'aperture,notarikon'.split(',')
		const scriptList = 'aperture.hack,protocol.breach'.split(',')
		return whitelist.indexOf(username) > -1 || scriptList.indexOf(context.calling_script) > -1
	}

	function transfer(amount,memo = "") {
		return JSON.stringify( #ms.accts.xfer_gc_to_caller({amount:amount,memo}) )
	}

	function isNPC(handle) {
		const npcs = "abandoned,abndnd,anon,anonymous,derelict,uknown,unidentified,unknown".split(",")
		for (var ih = 0; ih < npcs.length; ih++) {
			if (handle.includes(npcs[ih])) {
				return true
			}
		}
		return false
	}	

}