package app

import "time"

func publishTransportRuntimeObservabilitySnapshotChanged(reason string, clientIDs []string, ifaceIDs []string) {
	now := time.Now().UTC()
	snapshot := transportRuntimeObservabilitySnapshotResponse(now)
	if !snapshot.OK {
		return
	}
	normalizedClientIDs := normalizeTransportRuntimeObservabilityClientIDs(clientIDs)
	normalizedIfaceIDs := resolveTransportRuntimeObservabilityEventIfaceIDs(snapshot.Items, normalizedClientIDs, ifaceIDs)
	events.push("transport_runtime_snapshot_changed", TransportRuntimeObservabilityChangedEvent{
		Reason:      reason,
		GeneratedAt: snapshot.GeneratedAt,
		Count:       snapshot.Count,
		IfaceIDs:    normalizedIfaceIDs,
		ClientIDs:   normalizedClientIDs,
		Items:       snapshot.Items,
	})
}

func normalizeTransportRuntimeObservabilityClientIDs(clientIDs []string) []string {
	seen := map[string]struct{}{}
	out := make([]string, 0, len(clientIDs))
	for _, raw := range clientIDs {
		id := sanitizeID(raw)
		if id == "" {
			continue
		}
		if _, ok := seen[id]; ok {
			continue
		}
		seen[id] = struct{}{}
		out = append(out, id)
	}
	return out
}

func resolveTransportRuntimeObservabilityEventIfaceIDs(
	items []TransportRuntimeObservabilityItem,
	clientIDs []string,
	ifaceIDs []string,
) []string {
	seen := map[string]struct{}{}
	out := make([]string, 0, len(ifaceIDs)+len(clientIDs))
	add := func(raw string) {
		id := normalizeTransportIfaceID(raw)
		if id == "" {
			return
		}
		if _, ok := seen[id]; ok {
			return
		}
		seen[id] = struct{}{}
		out = append(out, id)
	}

	for _, raw := range ifaceIDs {
		add(raw)
	}
	for _, clientID := range clientIDs {
		for _, item := range items {
			if item.ClientID == clientID {
				add(item.IfaceID)
				continue
			}
			for _, memberID := range item.ClientIDs {
				if memberID == clientID {
					add(item.IfaceID)
					break
				}
			}
		}
	}
	if len(out) > 0 {
		return out
	}
	for _, item := range items {
		add(item.IfaceID)
	}
	return out
}