package http

import (
	"context"
	"database/sql"
	"encoding/json"
	"log/slog"
	"net/http"
	"os"
	"path/filepath"
	"sync"

	"github.com/google/uuid"

	"github.com/nextlevelbuilder/goclaw/internal/bus"
	"github.com/nextlevelbuilder/goclaw/internal/config"
	"github.com/nextlevelbuilder/goclaw/internal/i18n"
	"github.com/nextlevelbuilder/goclaw/internal/permissions"
	"github.com/nextlevelbuilder/goclaw/internal/skills"
	"github.com/nextlevelbuilder/goclaw/internal/store"
	"github.com/nextlevelbuilder/goclaw/pkg/protocol"
)

var (
	aggregateInstallDeps = skills.AggregateMissingDeps
	installManagedDeps   = skills.InstallDeps
	installSingleDep     = skills.InstallSingleDep
)

// SkillsHandler handles skill management HTTP endpoints.
type SkillsHandler struct {
	skills         store.SkillManageStore
	baseDir        string // filesystem base for skill content (skills-store/) — master tenant
	dataDir        string // parent data dir for tenant-scoped skill paths
	bundledDir     string // original bundled skills dir (fallback for broken managed copies)
	msgBus         *bus.MessageBus
	tenantCfgStore store.SkillTenantConfigStore
	tenantStore    store.TenantStore
	evolutionStore store.SkillEvolutionStore
	activityStore  store.ActivityStore
	db             *sql.DB  // for export/import direct queries
	uploadLocks    sync.Map // per-slug mutex; bounded by validated slug set, entries are tiny (*sync.Mutex)
	uploadLimitCfg config.SkillsConfig
	systemConfigs  store.SystemConfigStore
}

func (h *SkillsHandler) SetEvolutionStore(evolution store.SkillEvolutionStore, activity store.ActivityStore) {
	h.evolutionStore = evolution
	h.activityStore = activity
}

// NewSkillsHandler creates a handler for skill management endpoints.
func NewSkillsHandler(skills store.SkillManageStore, baseDir, dataDir, bundledDir string, msgBus *bus.MessageBus, tenantCfgStore store.SkillTenantConfigStore, tenantStore store.TenantStore) *SkillsHandler {
	return &SkillsHandler{skills: skills, baseDir: baseDir, dataDir: dataDir, bundledDir: bundledDir, msgBus: msgBus, tenantCfgStore: tenantCfgStore, tenantStore: tenantStore, uploadLimitCfg: config.SkillsConfig{MaxUploadSizeMB: config.DefaultSkillMaxUploadSizeMB}}
}

// tenantSkillsDir returns the skills-store directory scoped to the requesting tenant.
// Master tenant returns h.baseDir unchanged (backward compat).
func (h *SkillsHandler) tenantSkillsDir(r *http.Request) string {
	tid := store.TenantIDFromContext(r.Context())
	slug := store.TenantSlugFromContext(r.Context())
	return config.TenantSkillsStoreDir(h.dataDir, tid, slug)
}

func (h *SkillsHandler) skillUploadLock(scopeKey string) *sync.Mutex {
	actual, _ := h.uploadLocks.LoadOrStore(scopeKey, &sync.Mutex{})
	return actual.(*sync.Mutex)
}

// emitCacheInvalidate broadcasts a skill-related cache invalidation event.
// tenantID == uuid.Nil means global invalidation (master admin path).
// Existing grant-related callers pass tenantID == uuid.Nil since grants are
// stored globally; tenant-aware callers (tenant_config handlers) pass the
// caller's tenant ID so only that tenant's cached agents are invalidated.
func (h *SkillsHandler) emitCacheInvalidate(kind, key string, tenantID uuid.UUID) {
	if h.msgBus == nil {
		return
	}
	h.msgBus.Broadcast(bus.Event{
		Name: protocol.EventCacheInvalidate,
		Payload: bus.CacheInvalidatePayload{
			Kind:     kind,
			Key:      key,
			TenantID: tenantID,
		},
	})
}

// RegisterRoutes registers all skill management routes on the given mux.
func (h *SkillsHandler) RegisterRoutes(mux *http.ServeMux) {
	// Skill reads (viewer+)
	mux.HandleFunc("GET /v1/skills", h.authMiddleware(h.handleList))
	mux.HandleFunc("GET /v1/skills/{id}", h.authMiddleware(h.handleGet))
	mux.HandleFunc("GET /v1/agents/{agentID}/skills", h.authMiddleware(h.handleListAgentSkills))
	mux.HandleFunc("GET /v1/skills/{id}/versions", h.authMiddleware(h.handleListVersions))
	mux.HandleFunc("GET /v1/skills/{id}/files/{path...}", h.authMiddleware(h.handleReadFile))
	mux.HandleFunc("PUT /v1/skills/{id}/files/{path...}", h.adminMiddleware(h.handleWriteFile))
	mux.HandleFunc("GET /v1/skills/{id}/files", h.authMiddleware(h.handleListFiles))
	mux.HandleFunc("GET /v1/skills/{id}/evolution", h.authMiddleware(h.handleGetEvolution))
	mux.HandleFunc("GET /v1/skills/{id}/metrics", h.authMiddleware(h.handleGetSkillMetrics))
	mux.HandleFunc("GET /v1/skills/{id}/activity", h.adminMiddleware(h.handleGetSkillActivity))
	mux.HandleFunc("GET /v1/skills/{id}/evolution/suggestions", h.authMiddleware(h.handleListSkillSuggestions))
	// Skill writes (admin+)
	mux.HandleFunc("POST /v1/skills/upload", h.adminMiddleware(h.handleUpload))
	mux.HandleFunc("PUT /v1/skills/{id}", h.adminMiddleware(h.handleUpdate))
	mux.HandleFunc("DELETE /v1/skills/{id}", h.adminMiddleware(h.handleDelete))
	mux.HandleFunc("PATCH /v1/skills/{id}/evolution", h.tenantAdminMiddleware(h.handlePatchEvolution))
	mux.HandleFunc("POST /v1/skills/{id}/evolution/suggestions", h.tenantAdminMiddleware(h.handleCreateSkillSuggestion))
	mux.HandleFunc("POST /v1/skills/{id}/evolution/suggestions/{suggestionID}/approve", h.tenantAdminMiddleware(h.handleApproveSkillSuggestion))
	mux.HandleFunc("POST /v1/skills/{id}/evolution/suggestions/{suggestionID}/reject", h.tenantAdminMiddleware(h.handleRejectSkillSuggestion))
	mux.HandleFunc("POST /v1/skills/{id}/evolution/suggestions/{suggestionID}/apply", h.tenantAdminMiddleware(h.handleApplySkillSuggestion))
	mux.HandleFunc("GET /v1/skills/{id}/dependencies", h.adminMiddleware(h.handleSkillDependenciesStatus))
	mux.HandleFunc("POST /v1/skills/{id}/dependencies/scan", h.adminMiddleware(h.handleSkillDependenciesStatus))
	mux.HandleFunc("POST /v1/skills/{id}/dependencies/check", h.adminMiddleware(h.handleSkillDependenciesStatus))
	mux.HandleFunc("POST /v1/skills/{id}/dependencies/install", h.adminMiddleware(h.handleSkillDependenciesInstall))
	mux.HandleFunc("GET /v1/skills/{id}/access", h.adminMiddleware(h.handleGetSkillAccess))
	mux.HandleFunc("PATCH /v1/skills/{id}/access", h.adminMiddleware(h.handlePatchSkillAccess))
	mux.HandleFunc("GET /v1/skills/{id}/access/effective", h.adminMiddleware(h.handleGetSkillEffectiveAccess))
	mux.HandleFunc("GET /v1/skills/access/effective", h.adminMiddleware(h.handleListEffectiveAccess))
	// Skill grants (admin+)
	mux.HandleFunc("GET /v1/skills/{id}/grants/agent", h.adminMiddleware(h.handleListAgentGrants))
	mux.HandleFunc("POST /v1/skills/{id}/grants/agent", h.adminMiddleware(h.handleGrantAgent))
	mux.HandleFunc("DELETE /v1/skills/{id}/grants/agent/{agentID}", h.adminMiddleware(h.handleRevokeAgent))
	mux.HandleFunc("GET /v1/skills/{id}/grants/agents", h.adminMiddleware(h.handleListAgentGrants))
	mux.HandleFunc("POST /v1/skills/{id}/grants/agents", h.adminMiddleware(h.handleGrantAgent))
	mux.HandleFunc("DELETE /v1/skills/{id}/grants/agents/{agentID}", h.adminMiddleware(h.handleRevokeAgent))
	mux.HandleFunc("GET /v1/skills/{id}/grants/users", h.adminMiddleware(h.handleListUserGrants))
	mux.HandleFunc("POST /v1/skills/{id}/grants/user", h.adminMiddleware(h.handleGrantUser))
	mux.HandleFunc("DELETE /v1/skills/{id}/grants/user/{userID}", h.adminMiddleware(h.handleRevokeUser))
	mux.HandleFunc("POST /v1/skills/{id}/grants/users", h.adminMiddleware(h.handleGrantUser))
	mux.HandleFunc("DELETE /v1/skills/{id}/grants/users/{userID}", h.adminMiddleware(h.handleRevokeUser))
	// System-level operations: admin + master tenant only.
	// These execute shell commands (pip/npm install) and affect the entire server.
	mux.HandleFunc("POST /v1/skills/rescan-deps", h.adminMiddleware(h.handleRescanDeps))
	mux.HandleFunc("POST /v1/skills/install-deps", h.adminMiddleware(h.handleInstallDeps))
	mux.HandleFunc("POST /v1/skills/install-dep", h.adminMiddleware(h.handleInstallDep))
	mux.HandleFunc("GET /v1/skills/runtimes", h.adminMiddleware(h.handleRuntimes))
	mux.HandleFunc("POST /v1/skills/{id}/toggle", h.adminMiddleware(h.handleToggle))
	// Per-tenant overrides (admin+)
	mux.HandleFunc("PUT /v1/skills/{id}/tenant-config", h.adminMiddleware(h.handleSetTenantConfig))
	mux.HandleFunc("DELETE /v1/skills/{id}/tenant-config", h.adminMiddleware(h.handleDeleteTenantConfig))
	// Export / Import (admin+)
	mux.HandleFunc("GET /v1/skills/export/preview", h.adminMiddleware(h.handleSkillsExportPreview))
	mux.HandleFunc("GET /v1/skills/export", h.adminMiddleware(h.handleSkillsExport))
	mux.HandleFunc("POST /v1/skills/import", h.adminMiddleware(h.handleSkillsImport))
}

func (h *SkillsHandler) authMiddleware(next http.HandlerFunc) http.HandlerFunc {
	return requireAuth("", next)
}

// adminMiddleware requires admin role — used for system-level operations
// (rescan deps, install packages, toggle skills) that affect the entire server.
func (h *SkillsHandler) adminMiddleware(next http.HandlerFunc) http.HandlerFunc {
	return requireAuth(permissions.RoleAdmin, next)
}

func (h *SkillsHandler) tenantAdminMiddleware(next http.HandlerFunc) http.HandlerFunc {
	return h.adminMiddleware(func(w http.ResponseWriter, r *http.Request) {
		if store.IsMasterScope(r.Context()) {
			next(w, r)
			return
		}
		if !requireTenantAdmin(w, r, h.tenantStore) {
			return
		}
		next(w, r)
	})
}

// requireMasterTenant rejects requests from non-master tenants.
// System skill management (install packages, rescan deps) is a server-wide operation
// that should only be accessible to the master tenant or cross-tenant admins.
func (h *SkillsHandler) requireMasterTenant(w http.ResponseWriter, r *http.Request) bool {
	return requireMasterScope(w, r)
}

func (h *SkillsHandler) handleList(w http.ResponseWriter, r *http.Request) {
	skillList := h.skills.ListSkills(r.Context())

	// Merge per-tenant overrides into response when tenant-scoped
	tid := store.TenantIDFromContext(r.Context())
	if tid != uuid.Nil && h.tenantCfgStore != nil {
		overrides, err := h.tenantCfgStore.ListAll(r.Context(), tid)
		if err != nil {
			slog.Warn("skill tenant config list failed", "tenant", tid, "error", err)
		}
		if err == nil && len(overrides) > 0 {
			type skillWithTenant struct {
				store.SkillInfo
				TenantEnabled *bool `json:"tenant_enabled"`
			}
			enriched := make([]skillWithTenant, len(skillList))
			for i, sk := range skillList {
				enriched[i] = skillWithTenant{SkillInfo: sk}
				if skID, err := uuid.Parse(sk.ID); err == nil {
					if enabled, ok := overrides[skID]; ok {
						enriched[i].TenantEnabled = &enabled
					}
				}
			}
			writeJSON(w, http.StatusOK, map[string]any{"skills": enriched})
			return
		}
	}

	writeJSON(w, http.StatusOK, map[string]any{"skills": skillList})
}

func (h *SkillsHandler) handleGet(w http.ResponseWriter, r *http.Request) {
	locale := store.LocaleFromContext(r.Context())
	id := r.PathValue("id")
	skill, ok := h.skills.GetSkill(r.Context(), id)
	if !ok {
		writeJSON(w, http.StatusNotFound, map[string]string{"error": i18n.T(locale, i18n.MsgNotFound, "skill", id)})
		return
	}
	writeJSON(w, http.StatusOK, skill)
}

func (h *SkillsHandler) handleUpdate(w http.ResponseWriter, r *http.Request) {
	locale := store.LocaleFromContext(r.Context())
	idStr := r.PathValue("id")
	id, err := uuid.Parse(idStr)
	if err != nil {
		writeJSON(w, http.StatusBadRequest, map[string]string{"error": i18n.T(locale, i18n.MsgInvalidID, "skill")})
		return
	}

	// Ownership check (admins bypass)
	auth := resolveAuth(r)
	if !permissions.HasMinRole(auth.Role, permissions.RoleAdmin) {
		userID := store.UserIDFromContext(r.Context())
		if ownerID, found := h.skills.GetSkillOwnerID(r.Context(), id); found && ownerID != userID {
			writeJSON(w, http.StatusForbidden, map[string]string{"error": "only the skill owner can perform this action"})
			return
		}
	}

	var updates map[string]any
	if !bindJSON(w, r, locale, &updates) {
		return
	}
	// Prevent changing sensitive fields (use /toggle endpoint for enabled)
	delete(updates, "id")
	delete(updates, "owner_id")
	delete(updates, "file_path")
	delete(updates, "is_system")
	delete(updates, "enabled")

	if v, ok := updates["visibility"]; ok {
		vs, ok := v.(string)
		if !ok {
			writeJSON(w, http.StatusBadRequest, map[string]string{"error": i18n.T(locale, i18n.MsgInvalidVisibility, "")})
			return
		}
		if err := skills.ValidateVisibility(vs); err != nil {
			writeJSON(w, http.StatusBadRequest, map[string]string{"error": i18n.T(locale, i18n.MsgInvalidVisibility, vs)})
			return
		}
		updates["visibility"] = skills.NormalizeVisibility(vs)
	}

	if err := h.skills.UpdateSkill(r.Context(), id, updates); err != nil {
		writeJSON(w, http.StatusInternalServerError, map[string]string{"error": err.Error()})
		return
	}

	h.skills.BumpVersion()
	h.emitCacheInvalidate(bus.CacheKindSkills, idStr, uuid.Nil)
	emitAudit(h.msgBus, r, "skill.updated", "skill", idStr)
	writeJSON(w, http.StatusOK, map[string]string{"ok": "true"})
}

func (h *SkillsHandler) handleDelete(w http.ResponseWriter, r *http.Request) {
	locale := store.LocaleFromContext(r.Context())
	idStr := r.PathValue("id")
	id, err := uuid.Parse(idStr)
	if err != nil {
		writeJSON(w, http.StatusBadRequest, map[string]string{"error": i18n.T(locale, i18n.MsgInvalidID, "skill")})
		return
	}

	// Ownership check (admins bypass)
	auth := resolveAuth(r)
	if !permissions.HasMinRole(auth.Role, permissions.RoleAdmin) {
		userID := store.UserIDFromContext(r.Context())
		if ownerID, found := h.skills.GetSkillOwnerID(r.Context(), id); found && ownerID != userID {
			writeJSON(w, http.StatusForbidden, map[string]string{"error": "only the skill owner can perform this action"})
			return
		}
	}

	if err := h.skills.DeleteSkill(r.Context(), id); err != nil {
		if err.Error() == "cannot delete system skill" {
			writeJSON(w, http.StatusForbidden, map[string]string{"error": "cannot delete system skill"})
			return
		}
		writeJSON(w, http.StatusInternalServerError, map[string]string{"error": err.Error()})
		return
	}

	h.skills.BumpVersion()
	h.emitCacheInvalidate(bus.CacheKindSkills, idStr, uuid.Nil)
	emitAudit(h.msgBus, r, "skill.deleted", "skill", idStr)
	writeJSON(w, http.StatusOK, map[string]string{"ok": "true"})
}

// handleInstallDeps installs missing dependencies for all enabled skills, then re-checks status.
func (h *SkillsHandler) handleInstallDeps(w http.ResponseWriter, r *http.Request) {
	if !h.requireMasterTenant(w, r) {
		return
	}
	// Use explicit master tenant context for system skill operations,
	// consistent with rescanAndUpdate() pattern.
	masterCtx := store.WithTenantID(r.Context(), store.MasterTenantID)

	dirs := h.installableSkillDirs(masterCtx)
	if len(dirs) == 0 {
		writeJSON(w, http.StatusOK, map[string]string{"message": "no skills"})
		return
	}

	manifest, missing := aggregateInstallDeps(dirs)
	if len(missing) == 0 {
		updated, results := h.rescanAndUpdate(masterCtx)
		if updated > 0 {
			h.emitCacheInvalidate(bus.CacheKindSkills, "", uuid.Nil)
		}
		writeJSON(w, http.StatusOK, map[string]any{
			"message": "all deps satisfied",
			"updated": updated,
			"results": results,
		})
		return
	}

	if h.msgBus != nil {
		h.msgBus.Broadcast(bus.Event{
			Name:    protocol.EventSkillDepsInstalling,
			Payload: map[string]any{"count": len(missing)},
		})
	}

	result, err := installManagedDeps(masterCtx, manifest, missing)
	if err != nil {
		writeJSON(w, http.StatusInternalServerError, map[string]string{"error": err.Error()})
		return
	}

	updated, results := h.rescanAndUpdate(masterCtx)
	if updated > 0 {
		h.emitCacheInvalidate(bus.CacheKindSkills, "", uuid.Nil)
	}
	for _, depResult := range results {
		if h.msgBus != nil {
			h.msgBus.Broadcast(bus.Event{
				Name: protocol.EventSkillDepsChecked,
				Payload: map[string]any{
					"slug":    depResult.Slug,
					"status":  depResult.Status,
					"missing": depResult.Missing,
				},
			})
		}
	}

	if h.msgBus != nil {
		h.msgBus.Broadcast(bus.Event{
			Name:    protocol.EventSkillDepsInstalled,
			Payload: result,
		})
	}

	writeJSON(w, http.StatusOK, result)
}

// handleInstallDep installs a single dependency and re-checks all skill statuses.
// Body: {"dep": "pip:openpyxl"}
func (h *SkillsHandler) handleInstallDep(w http.ResponseWriter, r *http.Request) {
	if !h.requireMasterTenant(w, r) {
		return
	}
	locale := extractLocale(r)
	var body struct {
		Dep string `json:"dep"`
	}
	if !bindJSON(w, r, locale, &body) {
		return
	}
	if body.Dep == "" {
		writeJSON(w, http.StatusBadRequest, map[string]string{"error": "dep required"})
		return
	}

	if h.msgBus != nil {
		h.msgBus.Broadcast(bus.Event{
			Name:    protocol.EventSkillDepItemInstalling,
			Payload: map[string]any{"dep": body.Dep},
		})
	}

	ok, errMsg := installSingleDep(r.Context(), body.Dep)

	if h.msgBus != nil {
		payload := map[string]any{"dep": body.Dep, "ok": ok}
		if errMsg != "" {
			payload["error"] = errMsg
		}
		h.msgBus.Broadcast(bus.Event{
			Name:    protocol.EventSkillDepItemInstalled,
			Payload: payload,
		})
	}

	updated, _ := h.rescanAndUpdate(store.WithTenantID(r.Context(), store.MasterTenantID))
	if updated > 0 {
		h.emitCacheInvalidate(bus.CacheKindSkills, "", uuid.Nil)
	}

	writeJSON(w, http.StatusOK, map[string]any{"ok": ok, "error": errMsg})
}

type depResult struct {
	Slug    string   `json:"slug"`
	Status  string   `json:"status"`
	Missing []string `json:"missing,omitempty"`
}

func (h *SkillsHandler) installableSkillDirs(ctx context.Context) map[string]string {
	dirs := make(map[string]string)
	for _, sk := range h.skills.ListAllSkills(store.WithCrossTenant(ctx)) {
		if !sk.Enabled || sk.BaseDir == "" {
			continue
		}
		key := sk.ID
		if key == "" {
			key = sk.Slug
		}
		dirs[key] = sk.BaseDir
	}
	return dirs
}

// rescanAndUpdate re-checks enabled skills and updates their status + missing deps in DB.
func (h *SkillsHandler) rescanAndUpdate(ctx context.Context) (updated int, results []depResult) {
	allSkills := h.skills.ListAllSkills(store.WithCrossTenant(ctx))

	for _, sk := range allSkills {
		manifest := h.scanWithFallback(sk)
		updateCtx := skillTenantContext(ctx, sk)

		id, err := uuid.Parse(sk.ID)
		if err != nil {
			continue
		}

		if manifest == nil || manifest.IsEmpty() {
			changed := false
			// No deps needed — recover archived skills and clear stale persisted deps.
			if len(sk.MissingDeps) > 0 {
				_ = h.skills.StoreMissingDeps(updateCtx, id, nil)
				changed = true
			}
			if sk.Status == "archived" {
				_ = h.skills.UpdateSkill(updateCtx, id, map[string]any{"status": "active"})
				results = append(results, depResult{Slug: sk.Slug, Status: "active"})
				changed = true
				slog.Debug("rescan: recovered archived skill (no deps)", "slug", sk.Slug)
			} else {
				results = append(results, depResult{Slug: sk.Slug, Status: "ok"})
			}
			if changed {
				updated++
			}
			continue
		}

		ok, missing := skills.CheckSkillDeps(manifest)
		changed := false
		if !stringSlicesEqual(sk.MissingDeps, missing) {
			_ = h.skills.StoreMissingDeps(updateCtx, id, missing)
			changed = true
		}

		switch {
		case ok && sk.Status == "archived":
			_ = h.skills.UpdateSkill(updateCtx, id, map[string]any{"status": "active"})
			results = append(results, depResult{Slug: sk.Slug, Status: "active"})
			changed = true
		case !ok && sk.Status == "active":
			_ = h.skills.UpdateSkill(updateCtx, id, map[string]any{"status": "archived"})
			results = append(results, depResult{Slug: sk.Slug, Status: "archived", Missing: missing})
			changed = true
		case !ok:
			results = append(results, depResult{Slug: sk.Slug, Status: sk.Status, Missing: missing})
		default:
			results = append(results, depResult{Slug: sk.Slug, Status: "ok"})
		}
		if changed {
			updated++
		}

		slog.Debug("rescan: checked skill", "slug", sk.Slug, "ok", ok, "missing", len(missing))
	}

	if updated > 0 {
		h.skills.BumpVersion()
	}
	return updated, results
}

func skillTenantContext(ctx context.Context, sk store.SkillInfo) context.Context {
	if sk.TenantID != "" {
		if tid, err := uuid.Parse(sk.TenantID); err == nil && tid != uuid.Nil {
			return store.WithTenantID(ctx, tid)
		}
	}
	return store.WithTenantID(ctx, store.MasterTenantID)
}

func stringSlicesEqual(a, b []string) bool {
	if len(a) != len(b) {
		return false
	}
	for i := range a {
		if a[i] != b[i] {
			return false
		}
	}
	return true
}

// scanWithFallback scans skill deps from the managed dir, falling back to the
// bundled dir if the managed copy's scripts/ directory is missing or empty.
// If a fallback scan succeeds, re-copies the bundled scripts to the managed dir.
func (h *SkillsHandler) scanWithFallback(sk store.SkillInfo) *skills.SkillManifest {
	manifest := scanSkillDeps(sk.BaseDir)
	if manifest != nil && !manifest.IsEmpty() {
		return manifest
	}

	// Fallback: try bundled dir for system skills whose managed copy is broken.
	if !sk.IsSystem || h.bundledDir == "" {
		return manifest
	}

	managedScripts := filepath.Join(sk.BaseDir, "scripts")
	if _, err := os.Stat(managedScripts); err == nil {
		// scripts/ exists in managed dir but scanner found nothing — not a copy issue.
		return manifest
	}

	bundledSkillDir := filepath.Join(h.bundledDir, sk.Slug)
	bundledManifest := scanSkillDeps(bundledSkillDir)
	if bundledManifest == nil || bundledManifest.IsEmpty() {
		return manifest
	}

	slog.Warn("rescan: managed scripts/ missing, using bundled fallback",
		"slug", sk.Slug, "managed", sk.BaseDir, "bundled", bundledSkillDir)

	// Re-copy bundled scripts to managed dir so future scans work without fallback.
	bundledScripts := filepath.Join(bundledSkillDir, "scripts")
	if err := skills.CopyDir(bundledScripts, managedScripts); err != nil {
		slog.Error("rescan: failed to re-copy bundled scripts", "slug", sk.Slug, "error", err)
	}

	return bundledManifest
}

// handleRescanDeps re-checks dependencies for all skills (including archived) and updates their status.
func (h *SkillsHandler) handleRescanDeps(w http.ResponseWriter, r *http.Request) {
	if !h.requireMasterTenant(w, r) {
		return
	}
	updated, results := h.rescanAndUpdate(store.WithTenantID(r.Context(), store.MasterTenantID))
	if updated > 0 {
		// rescanAndUpdate bumped the skills version already; emit a global
		// invalidate so cached agent Loops pick up the new status set.
		h.emitCacheInvalidate(bus.CacheKindSkills, "", uuid.Nil)
	}
	writeJSON(w, http.StatusOK, map[string]any{
		"updated": updated,
		"results": results,
	})
}

// handleRuntimes returns the availability and version of prerequisite runtimes (python3, node, etc.).
func (h *SkillsHandler) handleRuntimes(w http.ResponseWriter, _ *http.Request) {
	writeJSON(w, http.StatusOK, skills.CheckRuntimes())
}

// handleToggle enables or disables a skill.
// Body: {"enabled": bool}
// When enabling: re-checks deps and updates status to "active" or "archived" accordingly.
func (h *SkillsHandler) handleToggle(w http.ResponseWriter, r *http.Request) {
	if !h.requireMasterTenant(w, r) {
		return
	}
	locale := store.LocaleFromContext(r.Context())
	idStr := r.PathValue("id")
	id, err := uuid.Parse(idStr)
	if err != nil {
		writeJSON(w, http.StatusBadRequest, map[string]string{"error": i18n.T(locale, i18n.MsgInvalidID, "skill")})
		return
	}

	var body struct {
		Enabled bool `json:"enabled"`
	}
	if !bindJSON(w, r, locale, &body) {
		return
	}

	if err := h.skills.ToggleSkill(r.Context(), id, body.Enabled); err != nil {
		writeJSON(w, http.StatusInternalServerError, map[string]string{"error": err.Error()})
		return
	}

	newStatus := ""
	if body.Enabled {
		// Re-check deps for this skill so its status reflects reality after being re-enabled.
		sk, ok := h.skills.GetSkillByID(r.Context(), id)
		if ok {
			manifest := h.scanWithFallback(sk)
			if manifest != nil && !manifest.IsEmpty() {
				depOk, missing := skills.CheckSkillDeps(manifest)
				_ = h.skills.StoreMissingDeps(r.Context(), id, missing)
				if depOk {
					newStatus = "active"
				} else {
					newStatus = "archived"
				}
			} else {
				newStatus = "active"
			}
			_ = h.skills.UpdateSkill(r.Context(), id, map[string]any{"status": newStatus})
		}
	}

	h.skills.BumpVersion()
	h.emitCacheInvalidate(bus.CacheKindSkills, idStr, uuid.Nil)
	emitAudit(h.msgBus, r, "skill.toggled", "skill", idStr)
	writeJSON(w, http.StatusOK, map[string]any{"ok": true, "enabled": body.Enabled, "status": newStatus})
}

// handleSetTenantConfig sets a per-tenant override for a skill.
func (h *SkillsHandler) handleSetTenantConfig(w http.ResponseWriter, r *http.Request) {
	if h.tenantCfgStore == nil {
		writeJSON(w, http.StatusNotImplemented, map[string]string{"error": "tenant config not available"})
		return
	}
	if !requireTenantAdmin(w, r, h.tenantStore) {
		return
	}
	locale := store.LocaleFromContext(r.Context())
	tid := store.TenantIDFromContext(r.Context())
	if tid == uuid.Nil {
		// Defense-in-depth: owner-role bypass in requireTenantAdmin could
		// otherwise reach here without a tenant scope. Reject explicitly so
		// a nil tid never flows into the cache invalidate emit as a global
		// wipe of every tenant's agent cache.
		writeJSON(w, http.StatusBadRequest, map[string]string{"error": "tenant context required"})
		return
	}

	idStr := r.PathValue("id")
	skillID, err := uuid.Parse(idStr)
	if err != nil {
		writeJSON(w, http.StatusBadRequest, map[string]string{"error": i18n.T(locale, i18n.MsgInvalidID, "skill")})
		return
	}

	var body struct {
		Enabled bool `json:"enabled"`
	}
	if err := json.NewDecoder(http.MaxBytesReader(w, r.Body, 1<<10)).Decode(&body); err != nil {
		writeJSON(w, http.StatusBadRequest, map[string]string{"error": i18n.T(locale, i18n.MsgInvalidJSON)})
		return
	}

	if err := h.tenantCfgStore.Set(r.Context(), tid, skillID, body.Enabled); err != nil {
		slog.Warn("set tenant skill config failed", "skill", idStr, "tenant", tid, "error", err)
		writeJSON(w, http.StatusInternalServerError, map[string]string{"error": i18n.T(locale, i18n.MsgInternalError, "skill tenant config")})
		return
	}

	emitAudit(h.msgBus, r, "skill.tenant_config.set", "skill", idStr)
	h.emitCacheInvalidate(bus.CacheKindSkills, idStr, tid)
	writeJSON(w, http.StatusOK, map[string]string{"status": "updated"})
}

// handleDeleteTenantConfig removes a per-tenant override for a skill (reverts to default).
func (h *SkillsHandler) handleDeleteTenantConfig(w http.ResponseWriter, r *http.Request) {
	if h.tenantCfgStore == nil {
		writeJSON(w, http.StatusNotImplemented, map[string]string{"error": "tenant config not available"})
		return
	}
	if !requireTenantAdmin(w, r, h.tenantStore) {
		return
	}
	locale := store.LocaleFromContext(r.Context())
	tid := store.TenantIDFromContext(r.Context())
	if tid == uuid.Nil {
		writeJSON(w, http.StatusBadRequest, map[string]string{"error": "tenant context required"})
		return
	}

	idStr := r.PathValue("id")
	skillID, err := uuid.Parse(idStr)
	if err != nil {
		writeJSON(w, http.StatusBadRequest, map[string]string{"error": i18n.T(locale, i18n.MsgInvalidID, "skill")})
		return
	}

	if err := h.tenantCfgStore.Delete(r.Context(), tid, skillID); err != nil {
		slog.Warn("delete tenant skill config failed", "skill", idStr, "tenant", tid, "error", err)
		writeJSON(w, http.StatusInternalServerError, map[string]string{"error": i18n.T(locale, i18n.MsgInternalError, "skill tenant config")})
		return
	}

	emitAudit(h.msgBus, r, "skill.tenant_config.deleted", "skill", idStr)
	h.emitCacheInvalidate(bus.CacheKindSkills, idStr, tid)
	writeJSON(w, http.StatusOK, map[string]string{"status": "deleted"})
}