package api

import (
	"encoding/json"
	"log"

	"crypto-miner-server/internal/atlas"
)

func (h *WSHub) handleAgentAtlasGossip(senderID string, payload json.RawMessage) {
	if !h.serverPolicySnapshot().AtlasLanGossipEnabled {
		return
	}
	var body struct {
		Hints []atlas.GossipHint `json:"hints"`
	}
	if err := json.Unmarshal(payload, &body); err != nil || len(body.Hints) == 0 {
		return
	}
	hints := atlas.NormalizeGossipHints(body.Hints)
	if len(hints) == 0 {
		return
	}
	h.relayAtlasGossip(senderID, hints)
}

func (h *WSHub) relayAtlasGossip(senderID string, hints []atlas.GossipHint) {
	senderSubnet := h.agentSubnetFor(senderID)
	if senderSubnet == "" {
		return
	}
	skips := atlas.SkipsFromHints(hints)
	if len(skips) == 0 {
		return
	}
	out := Message{
		Type: "atlas_gossip",
		Payload: mustMarshal(map[string]interface{}{
			"hints":           skips,
			"source_agent_id": senderID,
		}),
	}
	h.mu.RLock()
	defer h.mu.RUnlock()
	for id, ac := range h.agents {
		if id == senderID || h.agentSubnet[id] != senderSubnet {
			continue
		}
		if err := ac.SendJSON(out); err != nil {
			log.Printf("[atlas-gossip] relay to %s: %v", id, err)
		}
	}
}

func (h *WSHub) agentSubnetFor(agentID string) string {
	h.mu.RLock()
	subnet := h.agentSubnet[agentID]
	h.mu.RUnlock()
	if subnet != "" {
		return subnet
	}
	if h.db == nil {
		return ""
	}
	ag, err := h.db.GetAgent(agentID)
	if err != nil || ag == nil {
		return ""
	}
	return atlas.SubnetPrefix(ag.IP)
}