func (a *Airspace) thisIsNewContent(msg *adsb.CompositeMsg) (wasNew bool) {
// Lazy init
if a.RollAfter == time.Minute*0 {
a.RollAfter = DefaultRollAfter
}
if a.Aircraft == nil {
a.Aircraft = make(map[adsb.IcaoId]AircraftData)
}
sig := msg.GetSignature()
if _, existsCurr := a.CurrMsgs[sig]; !existsCurr {
// Add it into Curr in all cases
a.CurrMsgs[sig] = true
existsPrev := false
if a.PrevMsgs != nil {
_, existsPrev = a.PrevMsgs[sig]
}
// If the thing was already in prev, then it isn't new; else it is
return !existsPrev
}
return false
}
