float fTimer = 0.6; //interval to check for nearby agents
float fDistance = 10.0; //range to scan


integer OPEN = FALSE;
integer STEPS = 6;
float SINGLESTEP = 0.7;
float DEGREES = 19.0;
float FRAMEDURATION = 0.03;

float fSleep = 1.6; //wait after opening/closing

integer COUNTER = 0;


ANIMATION()
{
    COUNTER = 0;
    llSetTimerEvent(0.001);
}
STOP_ANIMATION()
{
    llSetTimerEvent(0.0);
}

default
{
    state_entry()
    { //start a timer on startup of the script
        llSetTimerEvent(fTimer);
    }

    timer()
    {
        list lAvatars = llGetAgentList(AGENT_LIST_PARCEL, []); //retrieve agent list in the parcel
        integer iCount; //helper variable
        integer i_bool_Found = FALSE; //becomes TRUE when an agent was detected within "fDistance"-range
        for (iCount = 0; iCount < llGetListLength(lAvatars); iCount++)
        { //loop through all agents...
            if (llVecDist(llList2Vector(llGetObjectDetails(llList2Key(lAvatars, iCount), [OBJECT_POS]),0), llGetPos()) <= fDistance)
            { //...and calculate distance from this prim
                i_bool_Found = TRUE; //avatar found...
                iCount = llGetListLength(lAvatars); //...break out of the loop
            }
        }
        if (i_bool_Found)
        { //must be on
            if (!OPEN)
            { //turn on
                OPEN = TRUE; //remember status = TRUE (on)
                state animation;
            }
        }
        else
        { //must be off
            if (OPEN)
            { //turn off
                OPEN = FALSE; //remember status = FALSE (off)
                state animation;
            }
        }
    }
}
state animation
{
    state_entry()
    {
        ANIMATION();
    }
    timer()
    {
        if (COUNTER == 0)
        {
            llSetTimerEvent(FRAMEDURATION);
        }
 
        vector v; rotation r;
        if (OPEN)
        {
            v = llGetPos() + <0.0, SINGLESTEP, 0.0>;
            r = llGetRot() / llEuler2Rot(<DEGREES, 0, 0> * DEG_TO_RAD);
        }
        else
        {
            v = llGetPos() - <0.0, SINGLESTEP, 0.0>;
            r = llGetRot() * llEuler2Rot(<DEGREES, 0, 0> * DEG_TO_RAD);
        }
        llSetLinkPrimitiveParamsFast(LINK_THIS, [PRIM_ROTATION, r, PRIM_POSITION, v]);
        COUNTER++;
        if (COUNTER >= STEPS)
        {
            STOP_ANIMATION();
            llSleep(fSleep);
            state default;
        }
    }
}