package graph

import (
	"crypto/sha256"
	"database/sql"
	"encoding/hex"
	"encoding/json"
	"math"
	"sort"
	"strings"
	"sync"
	"time"

	"github.com/local/glpi-neural-brain/internal/model"
)

type Store struct {
	mu                      sync.RWMutex
	nodes                   map[string]model.Node
	edges                   map[string]model.Edge
	vectors                 map[string][]float32
	version                 uint64
	persistedVersion        uint64
	pairCursor              int
	embeddingModel          string
	embeddingDigest         string
	embeddingMetaGeneration uint64
	mutations               MutationStats

	db          *sql.DB
	dbPath      string
	journalMode string

	dirtyNodes     map[string]uint64
	dirtyEdges     map[string]uint64
	dirtyVectors   map[string]uint64
	deletedNodes   map[string]uint64
	deletedEdges   map[string]uint64
	deletedVectors map[string]uint64

	analysisMu               sync.Mutex
	analysisQueue            chan analysisRecord
	analysisWG               sync.WaitGroup
	analysisLastMutations    MutationStats
	analysisPendingChanges   []GraphChange
	analysisPendingTruncated int
	analysisChangesDropped   uint64
	analysisDropped          uint64
	analysisLastError        string
	analysisLastPersisted    time.Time
	processID                string
	analysisDetailMu         sync.Mutex
	analysisDetailVersion    uint64
	analysisDetailCache      DetailedGraphAnalysis
	researchTaskMu           sync.Mutex
}

func ID(parts ...string) string {
	h := sha256.Sum256([]byte(strings.Join(parts, "\x00")))
	return hex.EncodeToString(h[:12])
}
func EdgeID(source, target, typ, origin string) string {
	return ID("edge", source, target, typ, origin)
}

func (s *Store) markNodeDirtyLocked(id string) {
	delete(s.deletedNodes, id)
	s.dirtyNodes[id] = s.version
}
func (s *Store) markEdgeDirtyLocked(id string) {
	delete(s.deletedEdges, id)
	s.dirtyEdges[id] = s.version
}
func (s *Store) markVectorDirtyLocked(id string) {
	delete(s.deletedVectors, id)
	s.dirtyVectors[id] = s.version
}
func (s *Store) markNodeDeletedLocked(id string) {
	delete(s.dirtyNodes, id)
	s.deletedNodes[id] = s.version
}
func (s *Store) markEdgeDeletedLocked(id string) {
	delete(s.dirtyEdges, id)
	s.deletedEdges[id] = s.version
}
func (s *Store) markVectorDeletedLocked(id string) {
	delete(s.dirtyVectors, id)
	s.deletedVectors[id] = s.version
}

func (s *Store) Dirty() bool {
	s.mu.RLock()
	defer s.mu.RUnlock()
	return len(s.dirtyNodes)+len(s.dirtyEdges)+len(s.dirtyVectors)+len(s.deletedNodes)+len(s.deletedEdges)+len(s.deletedVectors) > 0 || s.embeddingMetaGeneration > 0 || s.version != s.persistedVersion
}

// ConfigureEmbeddingModel records the model name before Ollama health data is
// available. A stored digest remains intact when the model name is unchanged.
func (s *Store) ConfigureEmbeddingModel(modelName string) int {
	return s.ConfigureEmbeddingIdentity(modelName, "")
}

// ConfigureEmbeddingIdentity records the model and, once known, its Ollama
// digest. Importing a database built with another model identity automatically
// invalidates all vectors while retaining nodes and edges for selective
// relearning.
func (s *Store) ConfigureEmbeddingIdentity(modelName, digest string) int {
	modelName = strings.TrimSpace(modelName)
	digest = strings.TrimSpace(digest)
	if modelName == "" {
		return 0
	}
	s.mu.Lock()
	defer s.mu.Unlock()

	modelChanged := s.embeddingModel != "" && s.embeddingModel != modelName
	digestChanged := digest != "" && s.embeddingDigest != "" && s.embeddingDigest != digest
	metadataChanged := s.embeddingModel != modelName || (digest != "" && s.embeddingDigest != digest)
	if !metadataChanged {
		return 0
	}

	s.version++
	removed := 0
	if modelChanged || digestChanged {
		for id, vector := range s.vectors {
			label := ""
			if node, ok := s.nodes[id]; ok {
				label = node.Label
			}
			delete(s.vectors, id)
			s.countVectorDeletedLocked()
			s.recordChangeLocked(vectorChange(id, "deleted", len(vector), label))
			s.deletedVectors[id] = s.version
			delete(s.dirtyVectors, id)
			removed++
		}
	}
	s.embeddingModel = modelName
	if modelChanged {
		s.embeddingDigest = digest
	} else if digest != "" {
		s.embeddingDigest = digest
	}
	s.embeddingMetaGeneration = s.version
	return removed
}

func (s *Store) UpsertNode(n model.Node) {
	s.mu.Lock()
	defer s.mu.Unlock()
	old, existed := s.nodes[n.ID]
	if n.UpdatedAt.IsZero() {
		n.UpdatedAt = time.Now().UTC()
	}
	if n.Weight == 0 {
		n.Weight = 1
	}
	if n.X == 0 && n.Y == 0 && n.Z == 0 {
		n.X, n.Y, n.Z = position(n.ID, n.Categories)
	}
	s.nodes[n.ID] = n
	if existed {
		s.countNodeUpdatedLocked()
	} else {
		s.countNodeCreatedLocked()
	}
	s.version++
	if existed {
		s.recordChangeLocked(nodeUpdateChange(old, n))
	} else {
		s.recordChangeLocked(nodeChange(n, "created"))
	}
	s.markNodeDirtyLocked(n.ID)
}
func (s *Store) UpsertEdge(e model.Edge) {
	s.mu.Lock()
	defer s.mu.Unlock()
	now := time.Now().UTC()
	if e.ID == "" {
		e.ID = EdgeID(e.Source, e.Target, e.Type, e.Origin)
	}
	old, existed := s.edges[e.ID]
	if e.CreatedAt.IsZero() {
		if existed {
			e.CreatedAt = old.CreatedAt
		} else {
			e.CreatedAt = now
		}
	}
	e.UpdatedAt = now
	if e.Weight == 0 {
		e.Weight = 1
	}
	s.edges[e.ID] = e
	if existed {
		s.countEdgeUpdatedLocked()
	} else {
		s.countEdgeCreatedLocked()
	}
	s.version++
	if existed {
		s.recordChangeLocked(edgeUpdateChange(old, e))
	} else {
		s.recordChangeLocked(edgeChange(e, "created"))
	}
	s.markEdgeDirtyLocked(e.ID)
}
func (s *Store) HasEdgeBetween(a, b string) bool {
	s.mu.RLock()
	defer s.mu.RUnlock()
	for _, e := range s.edges {
		if (e.Source == a && e.Target == b) || (e.Source == b && e.Target == a) {
			return true
		}
	}
	return false
}
func (s *Store) GetNode(id string) (model.Node, bool) {
	s.mu.RLock()
	defer s.mu.RUnlock()
	n, ok := s.nodes[id]
	return n, ok
}
func (s *Store) LookupExternal(id string) (model.Node, bool) {
	s.mu.RLock()
	defer s.mu.RUnlock()
	for _, n := range s.nodes {
		if strings.EqualFold(n.ExternalID, id) {
			return n, true
		}
	}
	return model.Node{}, false
}
func (s *Store) SetVector(id string, v []float64) {
	s.mu.Lock()
	defer s.mu.Unlock()
	converted := make([]float32, len(v))
	for i, value := range v {
		converted[i] = float32(value)
	}
	old, ok := s.vectors[id]
	if ok && float32SlicesEqual(old, converted) {
		return
	}
	s.vectors[id] = converted
	if ok {
		s.countVectorUpdatedLocked()
	} else {
		s.countVectorCreatedLocked()
	}
	s.version++
	label := ""
	if node, exists := s.nodes[id]; exists {
		label = node.Label
	}
	if ok {
		s.recordChangeLocked(vectorRecalculatedChange(id, len(old), len(converted), label))
	} else {
		s.recordChangeLocked(vectorChange(id, "created", len(converted), label))
	}
	s.markVectorDirtyLocked(id)
}
func (s *Store) Vector(id string) ([]float64, bool) {
	s.mu.RLock()
	defer s.mu.RUnlock()
	v, ok := s.vectors[id]
	if !ok {
		return nil, false
	}
	out := make([]float64, len(v))
	for i, value := range v {
		out[i] = float64(value)
	}
	return out, true
}

func (s *Store) ClearVectorsByDimension(dim int) int {
	s.mu.Lock()
	defer s.mu.Unlock()
	removed := 0
	for id, v := range s.vectors {
		if len(v) == dim {
			label := ""
			if node, ok := s.nodes[id]; ok {
				label = node.Label
			}
			delete(s.vectors, id)
			s.countVectorDeletedLocked()
			removed++
			s.version++
			s.recordChangeLocked(vectorChange(id, "deleted", len(v), label))
			s.markVectorDeletedLocked(id)
		}
	}
	return removed
}

func (s *Store) NodesForEmbedding() []model.Node {
	return s.NodesForEmbeddingScoped(NodeFilter{})
}

func (s *Store) NodesForEmbeddingFiltered(sources []string) []model.Node {
	return s.NodesForEmbeddingScoped(NodeFilter{Sources: sources})
}

func (s *Store) NodesForEmbeddingScoped(filter NodeFilter) []model.Node {
	s.mu.RLock()
	defer s.mu.RUnlock()
	out := []model.Node{}
	for _, n := range s.nodes {
		if n.Kind != "knowledge" && n.Kind != "ai-think" && n.Kind != "external" {
			continue
		}
		if !filter.Matches(n) {
			continue
		}
		if _, ok := s.vectors[n.ID]; !ok {
			out = append(out, n)
		}
	}
	sort.Slice(out, func(i, j int) bool { return out[i].ID < out[j].ID })
	return out
}
func (s *Store) KnowledgeNodes() []model.Node {
	s.mu.RLock()
	defer s.mu.RUnlock()
	out := []model.Node{}
	for _, n := range s.nodes {
		if n.Kind == "knowledge" || n.Kind == "ai-think" {
			out = append(out, n)
		}
	}
	return out
}
func (s *Store) ReplaceOrigins(origins []string, nodes []model.Node, edges []model.Edge) {
	originSet := make(map[string]struct{}, len(origins))
	for _, origin := range origins {
		originSet[origin] = struct{}{}
	}

	now := time.Now().UTC()
	incomingNodes := make(map[string]model.Node, len(nodes))
	for _, node := range nodes {
		if node.Weight == 0 {
			node.Weight = 1
		}
		normalizeNodeCollections(&node)
		incomingNodes[node.ID] = node
	}
	incomingEdges := make(map[string]model.Edge, len(edges))
	for _, edge := range edges {
		if edge.ID == "" {
			edge.ID = EdgeID(edge.Source, edge.Target, edge.Type, edge.Origin)
		}
		if edge.Weight == 0 {
			edge.Weight = 1
		}
		normalizeEdgeCollections(&edge)
		incomingEdges[edge.ID] = edge
	}

	s.mu.Lock()
	defer s.mu.Unlock()

	// Remove records from managed origins that disappeared from the source.
	for id, old := range s.nodes {
		if _, managed := originSet[old.Origin]; !managed {
			continue
		}
		if _, present := incomingNodes[id]; present {
			continue
		}
		delete(s.nodes, id)
		s.countNodeDeletedLocked()
		if _, hadVector := s.vectors[id]; hadVector {
			vector := s.vectors[id]
			delete(s.vectors, id)
			s.countVectorDeletedLocked()
			s.version++
			s.recordChangeLocked(vectorChange(id, "deleted", len(vector), old.Label))
			s.markVectorDeletedLocked(id)
		}
		s.version++
		s.recordChangeLocked(nodeChange(old, "deleted"))
		s.markNodeDeletedLocked(id)
	}
	for id, old := range s.edges {
		if _, managed := originSet[old.Origin]; !managed {
			continue
		}
		if _, present := incomingEdges[id]; present {
			continue
		}
		delete(s.edges, id)
		s.countEdgeDeletedLocked()
		s.version++
		s.recordChangeLocked(edgeChange(old, "deleted"))
		s.markEdgeDeletedLocked(id)
	}

	// Reconcile nodes instead of deleting and recreating every row on each scan.
	// This is what makes the scheduled SQLite flush truly incremental for an
	// unchanged knowledge base.
	for id, incoming := range incomingNodes {
		old, existed := s.nodes[id]
		if incoming.UpdatedAt.IsZero() {
			if existed && !old.UpdatedAt.IsZero() {
				incoming.UpdatedAt = old.UpdatedAt
			} else {
				incoming.UpdatedAt = now
			}
		}
		if incoming.X == 0 && incoming.Y == 0 && incoming.Z == 0 {
			if existed && (old.X != 0 || old.Y != 0 || old.Z != 0) {
				incoming.X, incoming.Y, incoming.Z = old.X, old.Y, old.Z
			} else {
				incoming.X, incoming.Y, incoming.Z = position(incoming.ID, incoming.Categories)
			}
		}

		oldEmbeddingFingerprint := ""
		if existed {
			oldEmbeddingFingerprint = embeddingFingerprint(old)
		}
		if existed && nodesEquivalent(old, incoming) {
			continue
		}

		s.nodes[id] = incoming
		if existed {
			s.countNodeUpdatedLocked()
		} else {
			s.countNodeCreatedLocked()
		}
		s.version++
		if existed {
			s.recordChangeLocked(nodeUpdateChange(old, incoming))
		} else {
			s.recordChangeLocked(nodeChange(incoming, "created"))
		}
		s.markNodeDirtyLocked(id)

		// Embeddings depend on text/categories/keywords, not on display
		// coordinates or unrelated metadata. Only invalidate a vector when its
		// actual embedding input changed.
		if existed && oldEmbeddingFingerprint != embeddingFingerprint(incoming) {
			if vector, hadVector := s.vectors[id]; hadVector {
				delete(s.vectors, id)
				s.countVectorDeletedLocked()
				s.version++
				s.recordChangeLocked(vectorChange(id, "deleted", len(vector), incoming.Label))
				s.markVectorDeletedLocked(id)
			}
		}
	}

	// Reconcile deterministic source edges. Timestamps are retained for an
	// unchanged edge so periodic scans do not produce needless writes.
	for id, incoming := range incomingEdges {
		old, existed := s.edges[id]
		if existed && edgesEquivalentIgnoringTimestamps(old, incoming) {
			continue
		}
		if incoming.CreatedAt.IsZero() {
			if existed && !old.CreatedAt.IsZero() {
				incoming.CreatedAt = old.CreatedAt
			} else {
				incoming.CreatedAt = now
			}
		}
		incoming.UpdatedAt = now
		s.edges[id] = incoming
		if existed {
			s.countEdgeUpdatedLocked()
		} else {
			s.countEdgeCreatedLocked()
		}
		s.version++
		if existed {
			s.recordChangeLocked(edgeUpdateChange(old, incoming))
		} else {
			s.recordChangeLocked(edgeChange(incoming, "created"))
		}
		s.markEdgeDirtyLocked(id)
	}

	// Remove any remaining edge whose endpoint no longer exists. This includes
	// AI-derived edges that referred to a source note removed from the KB.
	for id, edge := range s.edges {
		if _, ok := s.nodes[edge.Source]; !ok {
			delete(s.edges, id)
			s.countEdgeDeletedLocked()
			s.version++
			s.recordChangeLocked(edgeChange(edge, "deleted"))
			s.markEdgeDeletedLocked(id)
			continue
		}
		if _, ok := s.nodes[edge.Target]; !ok {
			delete(s.edges, id)
			s.countEdgeDeletedLocked()
			s.version++
			s.recordChangeLocked(edgeChange(edge, "deleted"))
			s.markEdgeDeletedLocked(id)
		}
	}
}

func embeddingFingerprint(node model.Node) string {
	return node.Label + "\x00" + node.Summary + "\x00" + strings.Join(node.Categories, "\x00") + "\x00" + strings.Join(node.Keywords, "\x00")
}

func normalizeNodeCollections(node *model.Node) {
	if node.Categories == nil {
		node.Categories = []string{}
	}
	if node.Keywords == nil {
		node.Keywords = []string{}
	}
	if node.Metadata == nil {
		node.Metadata = map[string]any{}
	}
}

func normalizeEdgeCollections(edge *model.Edge) {
	if edge.Evidence == nil {
		edge.Evidence = []model.Evidence{}
	}
	if edge.Metadata == nil {
		edge.Metadata = map[string]any{}
	}
}

func nodesEquivalent(a, b model.Node) bool {
	if a.ID != b.ID || a.Kind != b.Kind || a.Label != b.Label ||
		a.Summary != b.Summary || a.Status != b.Status || a.Origin != b.Origin ||
		a.ExternalID != b.ExternalID || a.URI != b.URI || a.Weight != b.Weight ||
		a.X != b.X || a.Y != b.Y || a.Z != b.Z {
		return false
	}
	return JSONEquivalent(a.Categories, b.Categories) &&
		JSONEquivalent(a.Keywords, b.Keywords) &&
		JSONEquivalent(a.Metadata, b.Metadata)
}

func edgesEquivalentIgnoringTimestamps(a, b model.Edge) bool {
	if a.ID != b.ID || a.Source != b.Source || a.Target != b.Target ||
		a.Type != b.Type || a.Origin != b.Origin || a.Status != b.Status ||
		a.Confidence != b.Confidence || a.Weight != b.Weight ||
		a.Explanation != b.Explanation {
		return false
	}
	return JSONEquivalent(a.Evidence, b.Evidence) && JSONEquivalent(a.Metadata, b.Metadata)
}

func JSONEquivalent(a, b any) bool {
	left, leftErr := json.Marshal(a)
	right, rightErr := json.Marshal(b)
	return leftErr == nil && rightErr == nil && string(left) == string(right)
}

func (s *Store) Version() uint64 {
	s.mu.RLock()
	defer s.mu.RUnlock()
	return s.version
}

func (s *Store) Counts() (nodes, edges int, version uint64) {
	s.mu.RLock()
	defer s.mu.RUnlock()
	nodes = len(s.nodes)
	for _, edge := range s.edges {
		if edge.Status != "rejected" {
			edges++
		}
	}
	return nodes, edges, s.version
}

func (s *Store) IdleNode(seed int64) (model.Node, bool) {
	s.mu.RLock()
	defer s.mu.RUnlock()
	if len(s.nodes) == 0 {
		return model.Node{}, false
	}
	index := int(seed % int64(len(s.nodes)))
	if index < 0 {
		index = -index
	}
	for _, node := range s.nodes {
		if index == 0 {
			return node, true
		}
		index--
	}
	return model.Node{}, false
}

func (s *Store) Snapshot() model.Snapshot {
	s.mu.RLock()
	defer s.mu.RUnlock()
	n := make([]model.Node, 0, len(s.nodes))
	e := make([]model.Edge, 0, len(s.edges))
	for _, x := range s.nodes {
		n = append(n, x)
	}
	for _, x := range s.edges {
		if x.Status == "rejected" {
			continue
		}
		e = append(e, x)
	}
	sort.Slice(n, func(i, j int) bool { return n[i].ID < n[j].ID })
	sort.Slice(e, func(i, j int) bool { return e[i].ID < e[j].ID })
	return model.Snapshot{Version: s.version, Nodes: n, Edges: e, UpdatedAt: time.Now().UTC()}
}
func (s *Store) Similar(query []float64, limit int) []model.Hit {
	return s.SimilarFiltered(query, limit, NodeFilter{})
}

func (s *Store) SimilarFiltered(query []float64, limit int, filter NodeFilter) []model.Hit {
	s.mu.RLock()
	defer s.mu.RUnlock()
	hits := []model.Hit{}
	for id, v := range s.vectors {
		n, ok := s.nodes[id]
		if !ok || (n.Kind != "knowledge" && n.Kind != "ai-think" && n.Kind != "external") || !filter.Matches(n) {
			continue
		}
		score := cosineMixed(query, v)
		hits = append(hits, model.Hit{NodeID: id, Label: n.Label, Score: score, Kind: n.Kind, Status: n.Status})
	}
	sort.Slice(hits, func(i, j int) bool { return hits[i].Score > hits[j].Score })
	if limit > 0 && len(hits) > limit {
		hits = hits[:limit]
	}
	return hits
}

// NextPair searches a bounded rotating window of anchor nodes instead of
// comparing the complete graph on every AI-THINK cycle. This keeps candidate
// selection responsive even for tens of thousands of knowledge nodes while the
// rotating cursor eventually visits the complete corpus.
func (s *Store) NextPair(min float64, anchorLimit int) (model.Node, model.Node, float64, bool, int) {
	return s.NextPairFiltered(min, anchorLimit, nil)
}

func (s *Store) NextPairFiltered(min float64, anchorLimit int, sources []string) (model.Node, model.Node, float64, bool, int) {
	return s.NextPairFilteredDepth(min, anchorLimit, sources, 0)
}

func (s *Store) NextPairFilteredDepth(min float64, anchorLimit int, sources []string, maxAIDepth int) (model.Node, model.Node, float64, bool, int) {
	return s.NextPairScopedDepth(min, anchorLimit, NodeFilter{Sources: sources}, maxAIDepth)
}

func (s *Store) NextPairScopedDepth(min float64, anchorLimit int, filter NodeFilter, maxAIDepth int) (model.Node, model.Node, float64, bool, int) {
	s.mu.Lock()
	defer s.mu.Unlock()

	nodes := make([]model.Node, 0, len(s.nodes))
	for _, n := range s.nodes {
		if n.Kind != "knowledge" && n.Kind != "ai-think" {
			continue
		}
		if !filter.Matches(n) {
			continue
		}
		if n.Kind == "ai-think" && maxAIDepth > 0 && graphNodeGenerationDepth(n) >= maxAIDepth {
			continue
		}
		if v, ok := s.vectors[n.ID]; ok && len(v) > 0 {
			nodes = append(nodes, n)
		}
	}
	if len(nodes) < 2 {
		return model.Node{}, model.Node{}, 0, false, 0
	}
	sort.Slice(nodes, func(i, j int) bool { return nodes[i].ID < nodes[j].ID })
	if anchorLimit <= 0 || anchorLimit > len(nodes) {
		anchorLimit = len(nodes)
	}

	blocked := make(map[string]struct{}, len(s.edges))
	for _, e := range s.edges {
		blocked[pairKey(e.Source, e.Target)] = struct{}{}
	}

	start := s.pairCursor % len(nodes)
	best := -1.0
	var a, b model.Node
	comparisons := 0
	for step := 0; step < anchorLimit; step++ {
		i := (start + step) % len(nodes)
		left := nodes[i]
		lv := s.vectors[left.ID]
		for j := 0; j < len(nodes); j++ {
			if i == j {
				continue
			}
			right := nodes[j]
			if left.Kind == "ai-think" && right.Kind == "ai-think" {
				continue
			}
			if _, exists := blocked[pairKey(left.ID, right.ID)]; exists {
				continue
			}
			rv := s.vectors[right.ID]
			if len(lv) != len(rv) {
				continue
			}
			comparisons++
			score := cosine32(lv, rv)
			if score >= min && score > best {
				best = score
				a, b = left, right
			}
		}
	}
	s.pairCursor = (start + anchorLimit) % len(nodes)
	return a, b, best, best >= 0, comparisons
}

func pairKey(a, b string) string {
	if a > b {
		a, b = b, a
	}
	return a + "\x00" + b
}

func (s *Store) BestPair(min float64) (model.Node, model.Node, float64, bool) {
	s.mu.RLock()
	defer s.mu.RUnlock()
	nodes := []model.Node{}
	for _, n := range s.nodes {
		if n.Kind == "knowledge" || n.Kind == "ai-think" {
			if _, ok := s.vectors[n.ID]; ok {
				nodes = append(nodes, n)
			}
		}
	}
	best := -1.0
	var a, b model.Node
	for i := 0; i < len(nodes); i++ {
		for j := i + 1; j < len(nodes); j++ {
			if edgeBetweenLocked(s.edges, nodes[i].ID, nodes[j].ID) {
				continue
			}
			score := cosine32(s.vectors[nodes[i].ID], s.vectors[nodes[j].ID])
			if score >= min && score > best {
				best = score
				a = nodes[i]
				b = nodes[j]
			}
		}
	}
	return a, b, best, best >= 0
}
func (s *Store) ConnectingEdges(ids []string) []string {
	set := map[string]bool{}
	for _, id := range ids {
		set[id] = true
	}
	s.mu.RLock()
	defer s.mu.RUnlock()
	var out []string
	for id, e := range s.edges {
		if set[e.Source] && set[e.Target] {
			out = append(out, id)
		}
	}
	return out
}
func graphNodeGenerationDepth(n model.Node) int {
	if n.Kind != "ai-think" {
		return 0
	}
	value, ok := n.Metadata["generation_depth"]
	if !ok {
		return 1
	}
	switch typed := value.(type) {
	case int:
		return typed
	case int64:
		return int(typed)
	case float64:
		return int(typed)
	case json.Number:
		value, _ := typed.Int64()
		return int(value)
	default:
		return 1
	}
}

func edgeBetweenLocked(edges map[string]model.Edge, a, b string) bool {
	for _, e := range edges {
		if (e.Source == a && e.Target == b) || (e.Source == b && e.Target == a) {
			return true
		}
	}
	return false
}
func float32SlicesEqual(a, b []float32) bool {
	if len(a) != len(b) {
		return false
	}
	for i := range a {
		if a[i] != b[i] {
			return false
		}
	}
	return true
}

func cosine32(a, b []float32) float64 {
	if len(a) == 0 || len(a) != len(b) {
		return 0
	}
	var dot, aa, bb float64
	for i := range a {
		av, bv := float64(a[i]), float64(b[i])
		dot += av * bv
		aa += av * av
		bb += bv * bv
	}
	if aa == 0 || bb == 0 {
		return 0
	}
	return dot / (math.Sqrt(aa) * math.Sqrt(bb))
}

func cosineMixed(a []float64, b []float32) float64 {
	if len(a) == 0 || len(a) != len(b) {
		return 0
	}
	var dot, aa, bb float64
	for i := range a {
		bv := float64(b[i])
		dot += a[i] * bv
		aa += a[i] * a[i]
		bb += bv * bv
	}
	if aa == 0 || bb == 0 {
		return 0
	}
	return dot / (math.Sqrt(aa) * math.Sqrt(bb))
}
func position(id string, cats []string) (float64, float64, float64) {
	seed := sha256.Sum256([]byte(id + "\x00" + strings.Join(cats, "|")))
	u := func(i int) float64 { return float64(int(seed[i%len(seed)])) / 255 }
	side := -1.0
	if seed[0]%2 == 0 {
		side = 1
	}
	biasY, biasZ := 0.0, 0.0
	if len(cats) > 0 {
		h := sha256.Sum256([]byte(cats[0]))
		biasY = (float64(h[0])/255 - .5) * .9
		biasZ = (float64(h[1])/255 - .5) * .65
	}
	for i := 0; i < 16; i++ {
		x := side * (0.08 + u(1+i)*0.72)
		y := biasY*.32 + (u(2+i)-.5)*1.18
		z := biasZ*.28 + (u(3+i)-.5)*.94
		if insideBrainShape(x, y, z) {
			return x, y, z
		}
	}
	return side * .34, biasY * .22, biasZ * .2
}

func insideBrainShape(x, y, z float64) bool {
	if math.Abs(x) < .045 && y > -.58 && y < .42 {
		return false
	}
	if y < -.76 || y > .82 {
		return false
	}
	taperY := y + math.Abs(z)*.10 - math.Max(0, math.Abs(x)-.58)*.18
	lx := (x + .35) / .58
	rx := (x - .35) / .58
	ny := taperY / .76
	nz := z / .58
	left := lx*lx+ny*ny+nz*nz <= 1
	right := rx*rx+ny*ny+nz*nz <= 1
	return left || right
}

func (s *Store) Analyze() model.GraphAnalysis {
	s.mu.RLock()
	defer s.mu.RUnlock()
	analysis := model.GraphAnalysis{NodeCount: len(s.nodes)}
	degree := make(map[string]int, len(s.nodes))
	knowledgeLinked := make(map[string]bool)
	parent := make(map[string]string, len(s.nodes))
	for id, n := range s.nodes {
		parent[id] = id
		if n.Status == "staging" {
			analysis.StagingNodes++
		}
		if n.Kind == "ai-think" {
			analysis.AIThinkNodes++
		}
		if n.Kind == "external" {
			analysis.ExternalNodes++
		}
	}
	var find func(string) string
	find = func(x string) string {
		p := parent[x]
		if p != x {
			parent[x] = find(p)
		}
		return parent[x]
	}
	union := func(a, b string) {
		ra, rb := find(a), find(b)
		if ra != rb {
			parent[rb] = ra
		}
	}
	for _, e := range s.edges {
		if e.Status == "rejected" {
			continue
		}
		if _, ok := s.nodes[e.Source]; !ok {
			continue
		}
		if _, ok := s.nodes[e.Target]; !ok {
			continue
		}
		analysis.EdgeCount++
		degree[e.Source]++
		degree[e.Target]++
		union(e.Source, e.Target)
		if e.Origin == "ai-inference" {
			analysis.AIEdges++
		}
		if e.Type == "contradicts" {
			analysis.Contradictions++
		}
		a, b := s.nodes[e.Source], s.nodes[e.Target]
		if (a.Kind == "knowledge" || a.Kind == "ai-think") && (b.Kind == "knowledge" || b.Kind == "ai-think" || b.Kind == "external") {
			knowledgeLinked[a.ID] = true
			if b.Kind != "external" {
				knowledgeLinked[b.ID] = true
			}
		}
	}
	roots := map[string]bool{}
	for id, n := range s.nodes {
		roots[find(id)] = true
		if (n.Kind == "knowledge" || n.Kind == "ai-think") && !knowledgeLinked[id] {
			analysis.KnowledgeOrphans++
		}
	}
	analysis.Components = len(roots)
	hubs := make([]model.Hub, 0, len(degree))
	for id, d := range degree {
		n := s.nodes[id]
		hubs = append(hubs, model.Hub{NodeID: id, Label: n.Label, Kind: n.Kind, Degree: d})
	}
	sort.Slice(hubs, func(i, j int) bool {
		if hubs[i].Degree == hubs[j].Degree {
			return hubs[i].Label < hubs[j].Label
		}
		return hubs[i].Degree > hubs[j].Degree
	})
	if len(hubs) > 8 {
		hubs = hubs[:8]
	}
	analysis.TopHubs = hubs
	return analysis
}