Help count down

Greetings everyone!!

Im an newbie scripter verry newbie, hope someone can help me whit this

I need an timer that counts down..but it must onely listen to the owner.
I must be able to set the time to count down in the chat line whit an comand like this "set time 60" for 60 minutes and when has count down to 0 it will say in the chat "time is over"

and it will allso be good if ite timer shows the count down time in an floating text..

Hope ther are some good scripter that can do this for me , i will be werry thankfull for it

and sorry for my bad spelling

integer intTimer = 0;
integer intListenHandle;

default
{
state_entry() {
llSetText("Touch to set the time.", <1.0,1.0,1.0>, 1.0);
}

listen (integer intChannel, string strName, key keySpeaker, string strMessage) {
list lstTokens = llParseString2List(strMessage, [" "], []);

if (llList2String(lstTokens, 0) == "time" {
intTimer = llList2Integer(lstTokens, 1);
llSetText("Time Remaining: " + (string)intTimer, <1.0,1.0,1.0>, 1.0);
llSetTimerEvent(1.0);
}

llListenRemove(intListenHandle);
}

touch_start(integer intDetected) {
if (llDetectedKey(0) != llGetOwner()) { return; }

llInstantMessage(llGetOwner(), "Enter /5time X in chat to start the timer.";
intListenHandle = llListen(5, "", llGetOwner(), "";
llSetTimerEvent(30.0);
}

timer () {
if (intListenHandle > 0) {
intListenHandle = 0;
llListenRemove(intListenHandle);
if (intTimer < 1) { return; }
}

if (intTimer-- < 1) {
llSetText("Touch to set the time.", <1.0,1.0,1.0>, 1.0);
llInstantMessage(llGetOwner(), "Time is over";
llSetTimerEvent(0.0);
}

else {
llSetText("Time Remaining: " + (string)intTimer, <1.0,1.0,1.0>, 1.0);
}
}
}

Thanks .. this is just waht i need ..

Oki this script works werry well.. but
what if i want to pause and reset the timer whit an command in the chat line how can i add that to the script ?