// St Mary's Primary School Bairnsdale
// Printer management script
//
// If printers are specified on the command line, just connect to them.
// Otherwise disconnect existing remote and fax printers, connect to those
// listed in printerN environment variables, and set the default printer
// to the first reachable one specified by a printerN variable.
//
// Stephen Thomas <flabdablet@gmail.com>
// Last updated 1-Feb-2012
//
// This is free software. Do whatever you like with it except
// hold me accountable for any grief it causes you. Constructive
// criticism always welcome.




// Everybody should always have access to at least the following printers.

extra = ['CutePDF Writer', '\\\\curricserver.curric.local\\Library copier'];



// Get access to some useful Windows facilities.

wmi = GetObject('winmgmts://./root/CIMV2');
wsh = new ActiveXObject('WScript.Shell');
fso = new ActiveXObject('Scripting.FileSystemObject');



// Issue diagnostic spew when run from cscript.

cscript = fso.GetFile(WScript.Fullname).Name.toLowerCase() == "cscript.exe";

function Log(message) {
	if (cscript) WScript.Echo(message);
}



// Windows makes extensive use of collections, which the standard jscript "for"
// statement won't enumerate. This helper function makes walking these much
// less clumsy.

function forEach(collection, func) {
	for (var e = new Enumerator(collection); !e.atEnd(); e.moveNext()) {
		var result = func(e.item());
		if (result) return result;
	}
}



// Printer management functions based on those found in %windir%\system32\prnmngr.vbs

function RemovePrinter(printer) {
	Log('Remove:  ' + printer);
	try {
	        printer = wmi.Get("Win32_Printer.DeviceID='" + printer + "'");
		if (printer) printer.Delete_();
	}
	catch (ex) {
		Log(ex.message);
	}
}

function ConnectPrinter(printer) {
	Log('Connect: ' + printer);
	try {
	        printers = wmi.Get("Win32_Printer");
		if (printers) printers.AddPrinterConnection(printer);
	}
	catch (ex) {
		Log(ex.message);
	}
}

function SetDefaultPrinter(printer) {
	Log('Choose:  ' + printer);
	try {
	        printer = wmi.Get("Win32_Printer.DeviceID='" + printer + "'");
		if (printer) printer.SetDefaultPrinter();
	}
	catch (ex) {
		Log(ex.message);
	}
}

function GetDefaultPrinter() {
	try {
		var defaultPrinters = wmi.ExecQuery('SELECT Name, Default FROM Win32_Printer WHERE default=true');
		var result = forEach (defaultPrinters, function (printer) {
			return printer.Name;
		});
		if (result) {
			Log('Chosen:  ' + result);
			return result;
		}
	}
	catch (ex) {
		Log(ex.message);
	}
	return "";
}



// Mainline starts here.

have = {};
want = {};
prefer = [];

// Make a list of the remote printers specified in the command line.

hasArgs = false;
forEach (WScript.Arguments, function (arg) {
	hasArgs = true;
	if (arg.match(/^\\\\/))	{
		want[arg.toLowerCase()] = arg;
	}
});

// If none were specified on the command line, we want to make connections
// conform to those specified in printerN environment variables.

if (!hasArgs) {

	// Collect the printers we want from environment variables.
	// Remember wanted connections and order of preference.

	forEach (wsh.Environment('PROCESS'), function (envVar) {
		if (envVar.match(/^printer/i)) {
			printer = envVar.replace(/^[^=]+=/, '').replace(/"/g, '');
			if (printer.match(/^\\\\/)) {
				want[printer.toLowerCase()] = printer;
			}
			prefer.push(printer);
		}
	});

	// Add printers from extra[] to the list as well.

	for (i in extra) {
		printer = extra[i];
		if (printer.match(/^\\\\/)) {
			want[printer.toLowerCase()] = printer;
		}
		prefer.push(printer);
	}

	// Make a list of existing printer connections. We don't want
	// fax printers on school workstations; lump them in with the
	// remote connections so they can get deleted as well.

	query = 'SELECT Name FROM Win32_Printer WHERE Local=false OR Name Like "%Fax%"'
	try {
		forEach (wmi.ExecQuery(query), function (printer) {
			have[printer.Name.toLowerCase()] = printer.Name;
		});
	}
	catch (ex) {
		Log(ex.message);
	}
	
	Log('\r\nHave:');
	for (printer in have) {
		Log(have[printer]);
	}
}

Log('\r\nWant:');
for (printer in want) {
	Log(want[printer]);
}

Log('\r\nPrefer:');
for (i in prefer) {
	Log(prefer[i]);
}

Log();

// Delete printers we have but no longer want.

for (printer in have) {
	if (!want.hasOwnProperty(printer)) {
		RemovePrinter(have[printer]);
	}
}

// Establish connections we want but don't already have.

for (printer in want) {
	if (!have.hasOwnProperty(printer)) {
		ConnectPrinter(want[printer]);
	}
}

// Set the default printer to the first one reachable.

defaultPrinter = GetDefaultPrinter();
for (i in prefer) {
	printer = prefer[i];
	if (defaultPrinter.toLowerCase() == printer.toLowerCase()) {
		break;
	}
	SetDefaultPrinter(printer);
	defaultPrinter = GetDefaultPrinter();
	if (defaultPrinter.toLowerCase() == printer.toLowerCase()) {
		break;
	}
}