const int nCaveInCycle = 7;

const int SHAKE_CHANCE = 90;
const int FURTHER_SHAKE_CHANCE = 67;
const int CAVEIN_CHANCE = 30;

const int DO_NOTHING = 0;
const int DO_SHAKE = 1;
const int DO_FURTHER_SHAKE = 2;
const int DO_CAVEIN = 3;

const int SHAKE_EVENT = 100;
const int NEAR_CAVEIN_EVENT = 200;
const int FULL_CAVEIN_EVENT = 300;


int isPCInArea(object oArea)
{
    object oThing = GetFirstObjectInArea(oArea);
    while(oThing != OBJECT_INVALID)
    {
        if( GetIsPC(oThing) )
        {
            return TRUE;
        }
        oThing = GetNextObjectInArea(oArea);
    }

    return FALSE;
}



void sendMessageToAllPCsInArea(object oArea, string sMessage)
{
    object oThing = GetFirstObjectInArea(oArea);
    while(oThing != OBJECT_INVALID)
    {
        if( GetIsPC(oThing) )
        {
            if( !GetLocalInt(oThing, "alreadyWarnedAboutCaveIn") )
            {
                DelayCommand(1.0f, SendMessageToPC(oThing, sMessage));
                SetLocalInt(oThing, "alreadyWarnedAboutCaveIn", TRUE);
            }
        }
        oThing = GetNextObjectInArea(oArea);
    }

}



void main()
{
    int nTimer = GetLocalInt(OBJECT_SELF, "timer");
    if( nTimer != nCaveInCycle )
    {
        SetLocalInt(OBJECT_SELF, "timer", ++nTimer);
        return;
    }
    else
    {
        int nCaveEvent = DO_NOTHING;
        if(d100(1) <= SHAKE_CHANCE)
        {
            // SpeakString("Shake", TALKVOLUME_SHOUT);
            nCaveEvent = DO_SHAKE;
            if(d100(1) <= FURTHER_SHAKE_CHANCE)
            {
                // SpeakString("Further Shake", TALKVOLUME_SHOUT);
                nCaveEvent = DO_FURTHER_SHAKE;
                if(d100(1) <= CAVEIN_CHANCE)
                {
                    // SpeakString("Cave In", TALKVOLUME_SHOUT);
                    nCaveEvent = DO_CAVEIN;
                }
            }
        }

        // SpeakString( "nCaveEvent = " + IntToString(nCaveEvent));

        object oArea = GetArea(OBJECT_SELF);
        int bIsPCsInArea = isPCInArea(oArea);
        if( nCaveEvent != DO_NOTHING && bIsPCsInArea )
        {
            int bHasCaveInSpots = FALSE;
            int nCurrentCount = 0;
            object oCaveInSpot;

            bHasCaveInSpots = GetLocalInt(OBJECT_SELF, "hasCaveInSpots");

            if(!bHasCaveInSpots)
            {
                oCaveInSpot = GetFirstObjectInArea();
            }
            else
            {
                oCaveInSpot = GetLocalObject(OBJECT_SELF, "caveInGenerator" + IntToString(nCurrentCount));
            }

            while( oCaveInSpot != OBJECT_INVALID )
            {
                if( bHasCaveInSpots || GetTag(oCaveInSpot) == "elv_caveingenerator" )
                {
                    event evShake = EventUserDefined(SHAKE_EVENT);
                    event evNearCaveIn = EventUserDefined(NEAR_CAVEIN_EVENT);
                    event eFullCaveIn = EventUserDefined(FULL_CAVEIN_EVENT);

                    switch(nCaveEvent)
                    {
                        case DO_SHAKE:
                            // SpeakString("Doing Shake", TALKVOLUME_SHOUT);
                            SignalEvent(oCaveInSpot, evShake);
                            break;

                        case DO_FURTHER_SHAKE:
                            // SpeakString("Doing Further Shake", TALKVOLUME_SHOUT);
                            SignalEvent(oCaveInSpot, evNearCaveIn);
                            break;

                        case DO_CAVEIN:
                            // SpeakString("Doing Cave In", TALKVOLUME_SHOUT);
                            SignalEvent(oCaveInSpot, eFullCaveIn);
                            break;
                    }
                }

                if(!bHasCaveInSpots)
                {
                    SetLocalObject(OBJECT_SELF, "caveInGenerator" + IntToString(nCurrentCount++), oCaveInSpot);
                    oCaveInSpot = GetNextObjectInArea();
                }
                else
                {
                    oCaveInSpot = GetLocalObject(OBJECT_SELF, "caveInGenerator" + IntToString(++nCurrentCount));
                }
            }

            if(!bHasCaveInSpots)
            {
                SetLocalInt(OBJECT_SELF, "hasCaveInSpots", TRUE);
            }
        }

        if (bIsPCsInArea)
        {
            sendMessageToAllPCsInArea( oArea, "Be careful, this cave appears to be very unstable.");
        }

        DeleteLocalInt(OBJECT_SELF, "timer");
    }
}