package main

import (
	"bufio"
	"context"
	"fmt"
	"log"
	"os"
	"path/filepath"
	"strings"
	"time"

	"github.com/kami/maven/internal/config"
	"github.com/kami/maven/internal/decision"
	"github.com/kami/maven/internal/delivery"
	"github.com/kami/maven/internal/delivery/voicesink"
	"github.com/kami/maven/internal/dialogue"
	"github.com/kami/maven/internal/ipc"
	"github.com/kami/maven/internal/llm"
	"github.com/kami/maven/internal/memory"
	"github.com/kami/maven/internal/phraser"
	"github.com/kami/maven/internal/router"
	"github.com/kami/maven/internal/store"
	"github.com/kami/maven/internal/stt"
	"github.com/kami/maven/internal/tool"
	"github.com/kami/maven/internal/tts"
	"github.com/kami/maven/internal/voice"
	"github.com/kami/maven/internal/weather"
	"github.com/kami/maven/internal/worker"
)

// voiceWiring — everything the daemon needs to run the audio path. Held by
// cmd/mavend/main.go alongside the other wirings; closed on shutdown.
type voiceWiring struct {
	server    *voice.Server
	sessions  *voice.Sessions
	voiceSink delivery.Sink
	embedder  router.Embedder
	handler   *reactiveHandler // the reactive handler for IPC Chat
	// worker clients (set when configured as Remote): closed on shutdown so
	// mavsttd / mavttsd don't keep a stale conn into a restarting daemon.
	sttClient *worker.Client
	ttsClient *worker.Client
	// transcriber — the STT in use, exposed so the meeting recorder
	// (cmd/mavend/capture.go) can reuse it. Maven has exactly one STT and does
	// not grow a second one for capture: this is the same whisper.cpp worker the
	// voice path talks to.
	transcriber stt.Transcriber
	// mcp — the MCP client, nil unless the `mcp` block configures an enabled
	// server (Vikunja #251). Its tools land in the same allowlist as every
	// other act, so nothing else here has to know about it.
	// pair — the workstation model with the resident one as the floor, nil
	// unless a `workstation` block names an address. Held here only so the
	// prober is stopped on shutdown; callers were handed it at build time.
	pair *llm.Pair
	mcp  *mcpWiring
	// home — the Home Assistant client, nil unless the `smarthome` block is
	// enabled (Vikunja #256). Its devices land in the same allowlist as every
	// other act, so nothing else here has to know about it.
	home *homeWiring
	// netscan — the LAN scanner, nil unless the `netscan` block is enabled
	// (Vikunja #257).
	netscan *netWiring
}

// close releases the listener + worker conns. Safe to call on nil (when
// voice is not wired — wireVoice returns nil,nil).
func (w *voiceWiring) close() {
	if w == nil {
		return
	}
	if w.embedder != nil {
		_ = w.embedder.Close()
	}
	if w.server != nil {
		_ = w.server.Close()
	}
	if w.sttClient != nil {
		_ = w.sttClient.Close()
	}
	if w.ttsClient != nil {
		_ = w.ttsClient.Close()
	}
	if w.pair != nil {
		w.pair.Stop()
	}
	w.mcp.close()
}

// wireVoice builds the audio path from cfg + a CoreAPI + a router. Returns
// nil wiring + nil error when voice isn't enabled (the caller's voice sink
// stays nil; the dispatcher's ChannelVoice routing drops silently).
//
// When voice is enabled, MUST wire a voicesink into the dispatcher's Voice
// slot using w.sessions (the caller does that — see main.go).
func wireVoice(cfg *config.Config, coreAPI ipc.CoreAPI, phr phraser.Phraser, memStore memory.Store, dataStore *store.Store, eco *ecosystemWiring) (*voiceWiring, error) {
	if cfg.Voice == nil || !cfg.Voice.Enabled {
		return nil, nil
	}
	w := &voiceWiring{}

	// ----- stt (Stub in-process OR Remote via worker socket) -----
	var transcriber stt.Transcriber
	if cfg.Voice.Stt != nil && cfg.Voice.Stt.Socket != "" {
		c := worker.Dial(cfg.Voice.Stt.Socket)
		w.sttClient = c
		lang := cfg.Voice.Stt.Lang
		if lang == "" {
			lang = cfg.Voice.Lang
		}
		transcriber = stt.NewRemote(c, lang)
	} else {
		transcriber = stt.NewStub()
	}
	w.transcriber = transcriber

	// ----- tts (Stub in-process OR Remote) -----
	var synthesizer tts.Synthesizer
	if cfg.Voice.Tts != nil && cfg.Voice.Tts.Socket != "" {
		c := worker.Dial(cfg.Voice.Tts.Socket)
		w.ttsClient = c
		lang := cfg.Voice.Tts.Lang
		if lang == "" {
			lang = cfg.Voice.Lang
		}
		synthesizer = tts.NewRemote(c, lang, cfg.Voice.Tts.Voice)
	} else {
		synthesizer = tts.NewStub()
	}

	// ----- router: embedder (ONNX when configured, floor HashEmbedder otherwise) -----
	var emb router.Embedder
	if cfg.Voice.Embedder != nil {
		onnx, err := router.NewONNXEmbedder(
			cfg.Voice.Embedder.ModelPath,
			cfg.Voice.Embedder.TokenizerPath,
			cfg.Voice.Embedder.LibPath,
		)
		if err != nil {
			w.close()
			return nil, fmt.Errorf("embedder: %w", err)
		}
		log.Printf("voice: onnx embedder loaded (%d dim)", onnx.Dim())
		emb = onnx
	} else {
		log.Printf("voice: embedder not configured, using HashEmbedder floor")
		emb = router.NewHashEmbedder(1024)
	}
	w.embedder = emb
	repairFactVectors(dataStore, emb)
	checkStoredEmbedder(dataStore, emb)

	// ----- tool executor (the enabled act allowlist, store-backed) -----
	// Config tools are the declarative bootstrap: seed them into the store as
	// enabled (editing mavend.json IS the human enable act). Ad-hoc tools are
	// enabled later through the authed mavweb surface. The executor + matcher
	// both read the store live, so a newly-enabled tool is runnable without a
	// daemon restart.
	seedTools(coreAPI, cfg.Voice.Tools)
	exec := tool.NewExecutor(coreAPI, time.Duration(cfg.Voice.ToolTimeout))
	// MCP servers (Vikunja #251): discovery PROPOSES tools into the same
	// allowlist, so an MCP tool is enabled by hand on /tools like any other and
	// runs through the same confirm turn. Off unless the `mcp` block configures
	// an enabled server.
	w.mcp = wireMCP(cfg, dataStore)
	if w.mcp != nil {
		exec = exec.WithMCP(w.mcp.caller())
	}
	// The house (Vikunja #256): same story as MCP. Discovery PROPOSES a row per
	// controllable device, always destructive, and Kami enables the ones he
	// wants on /tools. Off unless the `smarthome` block is enabled.
	w.home = wireSmartHome(cfg, dataStore)
	if w.home != nil {
		exec = exec.WithHome(w.home.caller())
	}
	// The LAN scanner (Vikunja #257): a read, bounded to the configured
	// subnets and rate-limited. Off unless the `netscan` block is enabled.
	w.netscan = wireNetScan(cfg, coreAPI)
	matcher := tool.NewMatcher(coreAPI).WithAliases(toolAliases(cfg.Voice.Tools))

	// ----- weather provider (Open-Meteo when configured, Stub otherwise) -----
	var weatherProvider weather.Provider
	var weatherLocation string
	if cfg.Voice.Weather != nil && cfg.Voice.Weather.Provider == "open-meteo" {
		weatherProvider = weather.NewOpenMeteoProvider()
		weatherLocation = cfg.Voice.Weather.DefaultLocation
		log.Printf("voice: weather provider: open-meteo (default location: %s)", cfg.Voice.Weather.DefaultLocation)
	} else {
		weatherProvider = weather.NewStubProvider()
		log.Printf("voice: weather provider: stub (not configured)")
	}

	// The replier uses the same llama-server as the phraser.
	var llmClient *llm.Client
	if lp, ok := phr.(*phraser.LLMPhraser); ok {
		// llmClientFor, not llm.New: this client must follow the phraser onto
		// the new llama-server when the resident model is swapped (Vikunja #250).
		llmClient = llmClientFor(lp, 60*time.Second)
	}
	// The workstation model sits above that one when it is configured and its
	// card is free. hot is what the router and the replier complete through:
	// either the pair, or the resident client alone, or nothing at all.
	hot, pair := modelSeam(cfg, llmClient)
	w.pair = pair
	// The phraser gets the same pair, which is what carries the workstation model
	// into the paths that do not go through `hot`: world questions (the naming
	// half), and the digestion worker's nudge and reminder phrasing (the silent
	// half). Wiring, so it happens once and before the voice server listens.
	if lp, ok := phr.(*phraser.LLMPhraser); ok && pair != nil {
		lp.UseRemote(pair)
	}
	// ----- router (the cascade; floor examples seed the classifier) -----
	// The act matcher's allowlist is exactly the enabled tool names — the
	// router only matches acts the executor can run (one source of truth).
	threshold := cfg.Voice.RouterThreshold
	if threshold <= 0 {
		threshold = config.DefaultRouterThreshold
	}
	// The resident model routes by default: 63.2% of held-out intents right
	// against the classifier's 50.0%, at about 1s a turn instead of 30ms (see
	// config.VoiceConfig.LLMRouter). The classifier always stays wired as the
	// fallback, so a model error never breaks a turn.
	rtr := buildRouter(emb, matcher, threshold, pickLLMRouter(cfg.Voice.UseLLMRouter(), hot))

	// ----- sessions registry (shared with voicesink) -----
	sessions := voice.NewSessions()
	w.sessions = sessions

	// ----- voice sink (proactive nudges: dispatcher → voicesink → tts → push to client) -----
	w.voiceSink = voicesink.New(synthesizer, sessions)

	// ----- memory (long-term vector storage) -----
	// Persistent (store-backed, survives restarts) when the daemon passes one;
	// falls back to the in-memory floor otherwise (tests / no-store paths).
	if memStore == nil {
		memStore = memory.NewInMemoryStore()
	}

	// ----- dialogue (multi-turn slot carry-over; dialogueSessionTTL follow-up window) -----
	// Store-backed when the daemon passes a store, so a restart mid-conversation
	// keeps the thread (Vikunja #363). Sessions past their TTL are dropped on
	// load, never revived. Clarify's parked question stays in memory only, and
	// that is a decision rather than an omission (Vikunja #385, docs/design.md):
	// a restart expires it, so the thread comes back and the open question does
	// not.
	const dialogueSessionTTL = 2 * time.Minute
	var dialogueSessions *dialogue.SessionStore
	if dataStore != nil {
		dialogueSessions = dialogue.NewPersistentSessionStore(dialogueSessionTTL, dataStore)
		if err := dialogueSessions.Load(context.Background(), time.Now()); err != nil {
			log.Printf("dialogue: load saved sessions: %v", err)
		}
	} else {
		dialogueSessions = dialogue.NewSessionStore(dialogueSessionTTL)
	}
	clarifyStore := dialogue.NewClarifyStore(clarifyTTL)
	timeParser := router.NewPythonDateParser()

	// ----- replier (LLM-backed when the engine is on, Stub floor otherwise) -----
	replier := voice.Replier(voice.NewStubReplier())
	if hot != nil {
		replier = newLLMReplier(hot, contextBlockFn(cfg, time.Now))
	}

	// ----- the handler (the reactive path; closes over stt / tts / router / coreAPI / memory) -----
	h := &reactiveHandler{
		stt:     transcriber,
		tts:     synthesizer,
		router:  rtr,
		api:     coreAPI,
		tools:   exec,
		matcher: matcher,
		replier: replier,
		phraser: phr,
		now:     time.Now,
		feedsOn: cfg.Feeds != nil,
		home:    w.home,
		netscan: w.netscan,
		// nil unless `crawl.on_demand` is on: reading a page he names is a
		// capability, and capabilities are off unless configured.
		crawler: onDemandCrawler(cfg),
		// nil unless a `search` block names a SearXNG instance. External search
		// is off unless configured, and configuring it is the whole opt-in.
		search: wireSearch(cfg),
		// nil unless a `kiwix` block names a server. Same swap-aware client the
		// router and replier use, so the rewriter follows a model swap.
		kiwix:           wireKiwix(cfg, llmClient),
		weatherProvider: weatherProvider,
		weatherLocation: weatherLocation,
		recall: recallWiring{
			embedder:  emb,
			memStore:  memStore,
			minScore:  cfg.Voice.QueryMinScore,
			minMargin: cfg.Voice.QueryMinMargin,
		},
		dataStore:        dataStore,
		dialogueSessions: dialogueSessions,
		// Always on (V-564). The record is the instrument the rest of V-558 is
		// measured with, and one that only runs when a flag is set is not there
		// on the night the misroute happens.
		decisions:    decision.NewRing(),
		clarifyStore: clarifyStore,
		// 0 here (unset config) ⇒ the dialogue default.
		clarifyMaxAttempts: cfg.Voice.ClarifyMaxAttempts,
		extractor:          router.Extractor{Time: timeParser, Acts: matcher, Facts: router.DefaultFactParser{}},
		timeParser:         timeParser,
		ecosystem:          eco,
	}

	// ----- the server (TCP listener) -----
	srv := voice.NewServer(cfg.Voice.Bind, h, sessions)
	if err := srv.Listen(); err != nil {
		w.close()
		return nil, fmt.Errorf("voice listen: %w", err)
	}
	w.server = srv
	w.handler = h

	return w, nil
}

// pickLLMRouter returns the LLM router when the operator asked for it and there
// is a llama-server to talk to, and nil otherwise. nil is safe: the cascade then
// routes with the classifier, so an unusable setting costs accuracy, not turns.
// modelSeam builds the completion seam the hot paths use: routing and replies.
//
// With no `workstation` block it is the resident client and nothing probes
// anything, which is today's deploy exactly. With one, it is an llm.Pair that
// prefers the workstation and falls back to the resident model silently — the
// silent half of the degradation rule (docs/offload.md), because the big model
// is only better here and the 1.7B is today's shipping quality. He is never
// told which of the two phrased his reply.
//
// A nil resident client means the phraser is not an LLM phraser. There is then
// no floor, and a Pair with no floor is a configuration mistake rather than a
// degraded mode, so the seam is nil and the cascade routes with the classifier.
func modelSeam(cfg *config.Config, resident *llm.Client) (router.Completer, *llm.Pair) {
	if resident == nil {
		if cfg.Workstation != nil {
			log.Printf("voice: a workstation is configured but there is no resident model to floor it with — ignoring the block")
		}
		return nil, nil
	}
	if cfg.Workstation == nil {
		return resident, nil
	}
	ws := cfg.Workstation
	pair := llm.NewPair(
		llm.New(ws.URL, time.Duration(ws.Timeout)),
		resident,
		ws.Health,
		time.Duration(ws.Probe),
	)
	pair.Start(context.Background())
	log.Printf("voice: workstation model at %s, probed every %s, resident model as the floor",
		ws.URL, time.Duration(ws.Probe))
	return pair, pair
}

func pickLLMRouter(enabled bool, c router.Completer) *router.LLMRouter {
	if !enabled {
		return nil
	}
	if c == nil {
		log.Printf("voice: voice.llm_router is on but there is no llama-server to route with (the phraser is not an LLM phraser) — using the classifier instead")
		return nil
	}
	log.Printf("voice: LLM router enabled")
	return router.NewLLMRouter(c)
}

// buildRouter constructs the reactive-path router with the given embedder
// and confidence threshold.
//   - stage-0 grammars from DefaultActMatcher whose fn allowlist is exactly
//     the enabled tool names (actFns) — the router only matches acts the
//     executor can run. Empty ⇒ every act refuses at the matcher.
//   - The embedder is provided by wireVoice: HashEmbedder (floor) when no
//     embedder config is present, or the ONNX multilingual model when
//     configured — same interface, one constructor change.
//   - The classifier is floored by seedClassifier, which loads one file per
//     intent from seedDir (models/seeds/<intent>.txt) — see seedClassifier
//     below for the current intent list and file names.
//   - Threshold is from voice.router_threshold config (default 0.55).
func buildRouter(emb router.Embedder, acts router.ActMatcher, threshold float64, llmR *router.LLMRouter) *router.Router {
	cls := router.NewClassifier(emb)
	seedClassifier(cls)
	grammars := router.DefaultGrammars(acts)
	grammars = append(grammars, router.SystemTimeDateGrammars()...)
	// After the time/date rules on purpose: "какой сегодня день" is a clock
	// question and must keep reaching replySystem, while "что у меня сегодня"
	// is an agenda question and must not.
	grammars = append(grammars, router.AgendaQueryGrammars()...)
	// Same reason as the agenda rules, for the feeds: "что нового в лентах?"
	// routed system and answered "пока не умею" (Vikunja #474).
	grammars = append(grammars, router.FeedQueryGrammar())
	// The list side of the same exposure: a phrasing with no possessive in it
	// ("список дел") routed system and never reached queryTasks (Vikunja #467).
	grammars = append(grammars, router.TaskListGrammar())
	grammars = append(grammars, router.ListGrammars()...)
	grammars = append(grammars, router.ReminderGrammar())
	// Before the capture marker, because "отметь" is a capture verb and "отметь
	// второй пункт" is not a note. The Praxis rules are the narrower claim — a
	// lifecycle verb AND an item named — so they get first refusal (Vikunja #516).
	grammars = append(grammars, router.PraxisGrammars()...)
	// Last, and it matches any utterance shape — its Build is the filter. An
	// explicit capture marker beats the model, which called it an act and
	// rewrote the task text (Vikunja #467). After the rules above because a
	// marker never collides with a clock or agenda question.
	// After Praxis, whose bare "закрой" claim this rule cannot reach (it needs the
	// board noun), and before the capture marker, which would otherwise read
	// "убери из задач купить молоко" as a new task (Vikunja #512).
	grammars = append(grammars, router.TaskStatusGrammar())
	// Before the capture markers, which all need an object. A capture verb
	// alone is a fact with no key, and the clarify path asks for it rather than
	// letting the model invent an answer (Vikunja #557).
	grammars = append(grammars, router.BareCaptureGrammar()...)
	grammars = append(grammars, router.TaskCaptureGrammar())
	// After the capture marker, so "запиши" still wins over "расскажи", and
	// last overall because it matches on the first word alone: "расскажи про
	// X" is a world question the model called a fact (Vikunja #498).
	grammars = append(grammars, router.NarrativeQueryGrammars()...)
	return router.New(router.Config{
		Grammars:   grammars,
		Classifier: cls,
		Extractor: router.Extractor{
			Time:  router.NewPythonDateParser(),
			Acts:  acts,
			Facts: router.DefaultFactParser{},
		},
		Threshold: threshold,
		LLM:       llmR,
	})
}

// seedDir is the directory containing intent seed files, relative to the repo
// root. Each file is named <intent>.txt and holds one training example per
// line (blank lines and lines starting with # are ignored).
const seedDir = "models/seeds"

// seedPath resolves seedDir against the working directory, walking up until it
// finds it. The daemon runs from the repo root and the first candidate hits.
//
// A test does not: `go test ./cmd/mavend/` runs with the working directory at
// cmd/mavend, so every open failed and the simulator scenarios replayed a whole
// scripted day against a classifier holding zero examples (Vikunja #465). They
// passed, which is the part that matters — a green simulator was not exercising
// the routing the deploy runs, and a regression in the seed set could not have
// shown up there.
//
// Bounded at five levels, so a daemon started somewhere without the seeds logs
// the same failure it always did rather than walking to the filesystem root.
func seedPath() string {
	dir := seedDir
	for i := 0; i < 5; i++ {
		if st, err := os.Stat(dir); err == nil && st.IsDir() {
			return dir
		}
		dir = filepath.Join("..", dir)
	}
	return seedDir
}

// seedClassifier floors the embedded examples so the cold-boot path
// doesn't return ErrNoIntents. Loads examples from seedDir — one file per
// intent (act.txt, reminder.txt, fact.txt, note.txt, query.txt, chat.txt,
// system.txt). When the classifier can't decide it falls through to
// Clarify — the last-resort path asks the user to rephrase rather than
// guessing wrong.
func seedClassifier(c *router.Classifier) {
	intents := []router.Intent{
		router.IntentAct,
		router.IntentReminder,
		router.IntentFact,
		router.IntentNote,
		router.IntentQuery,
		router.IntentChat,
		router.IntentSystem,
	}
	total := 0
	for _, intent := range intents {
		n, err := loadSeedFile(c, intent)
		if err != nil {
			log.Printf("voice: seed %s: %v", intent, err)
			continue
		}
		total += n
	}
	log.Printf("voice: loaded %d seed examples from %s", total, seedPath())
}

func loadSeedFile(c *router.Classifier, intent router.Intent) (int, error) {
	path := filepath.Join(seedPath(), string(intent)+".txt")
	f, err := os.Open(path)
	if err != nil {
		return 0, fmt.Errorf("open %s: %w", path, err)
	}
	defer f.Close()

	var count int
	sc := bufio.NewScanner(f)
	for sc.Scan() {
		line := strings.TrimSpace(sc.Text())
		if line == "" || strings.HasPrefix(line, "#") {
			continue
		}
		if err := c.AddExample(context.Background(), intent, line); err != nil {
			log.Printf("voice: seed %s: skipping %q: %v", intent, line, err)
			continue
		}
		count++
	}
	if err := sc.Err(); err != nil {
		return count, fmt.Errorf("scan %s: %w", path, err)
	}
	return count, nil
}

// toolAliases collects the spoken phrases per tool name. Without them the act
// matcher only ever matched the English tool name, so no Russian utterance could
// reach a tool and every homelab act fell to proposeGap (V-633).
func toolAliases(tools []config.ToolConfig) map[string][]string {
	out := make(map[string][]string, len(tools))
	for _, tc := range tools {
		if tc.Name == "" || len(tc.Aliases) == 0 {
			continue
		}
		out[tc.Name] = tc.Aliases
	}
	return out
}

// seedTools upserts the config-declared tools into the store as enabled. Editing
// mavend.json is a human act, so a config tool is enabled by definition; this
// makes the declarative config the reproducible bootstrap while the store stays
// the single runtime source of truth (mavweb enables ad-hoc ones on top).
func seedTools(api ipc.CoreAPI, tools []config.ToolConfig) {
	ctx := context.Background()
	now := time.Now()
	n := 0
	for _, tc := range tools {
		if tc.Name == "" || len(tc.Cmd) == 0 {
			log.Printf("voice: skipping malformed tool config %+v", tc)
			continue
		}
		if err := api.EnableTool(ctx, tc.Name, tc.Cmd, tc.Destructive, tc.Scope, now); err != nil {
			log.Printf("voice: seed tool %q: %v", tc.Name, err)
			continue
		}
		n++
	}
	log.Printf("voice: seeded %d act tools from config", n)
}

// repairFactVectors brings stored fact vectors in line with the facts they name
// (#493), once per box, before the embedder marker is even looked at.
//
// Automatic and not a flag, unlike -reembed: only voice-tapped facts are in
// this index, so the work is tens of embeddings rather than the thousands of
// notes that made the backfill a deliberate act. And the box that needs it is
// broken in a way nobody can see — recall answers with the wrong text and
// nothing logs an error — so waiting for an operator to know to run it is how
// the defect survived four restarts in the first place.
func repairFactVectors(dataStore *store.Store, emb router.Embedder) {
	if dataStore == nil {
		return
	}
	res, err := dataStore.RepairFactVectors(context.Background(),
		// EmbedPassage, the stored side, same as every other writer of these
		// vectors.
		func(ctx context.Context, text string) ([]float32, error) {
			return router.EmbedPassage(ctx, emb, text)
		})
	if err != nil {
		log.Printf("voice: fact vector repair failed, no marker written and nothing half-done — retried next start: %v", err)
		return
	}
	if res.Skipped || res.Rewritten+res.Dropped == 0 {
		return
	}
	log.Printf("voice: fact vector repair — %d re-embedded from the fact they name, %d dropped as voided or superseded, %d already right, took %s (#493)",
		res.Rewritten, res.Dropped, res.Kept, res.Took.Round(time.Millisecond))
}

// reembedOnStart is the -reembed flag (set in run()). Opt-in on purpose: see
// runReembed.
var reembedOnStart bool

// allowSeedOnStart is the -allow-seed flag (set in run()). Opt-in, and the
// default is the one that matters: a box nobody is testing has no live path to
// write a fact into the past. See seed.go and Vikunja #518.
var allowSeedOnStart bool

// checkStoredEmbedder compares the embedder we just loaded with the one that
// wrote the vectors already in the DB (Vikunja #378).
//
// The two models we have both make 384-dim vectors, so a size check catches
// nothing: after a swap, recall silently compares vectors from different
// spaces and the scores are noise. So we say it out loud. Recall itself is not
// changed here — the fix is `mavend -reembed`.
func checkStoredEmbedder(dataStore *store.Store, emb router.Embedder) {
	if dataStore == nil {
		return
	}
	current := router.EmbedderID(emb)
	if reembedOnStart {
		runReembed(dataStore, emb, current)
		return
	}
	stored, mismatch, err := dataStore.CheckEmbedder(context.Background(), current)
	if err != nil {
		log.Printf("voice: embedder marker check failed: %v", err)
		return
	}
	if mismatch {
		log.Printf("voice: WARNING embedder MISMATCH — stored vectors were written by %q but the configured embedder is %q; recall scores are noise until the notes and facts are re-embedded — run `mavend -reembed` once (Vikunja #378)", stored, current)
		return
	}
	log.Printf("voice: embedder marker ok (%s)", current)
}

// runReembed is the one-shot backfill behind -reembed.
//
// Why a flag and not automatic on mismatch: the embedder is ONNX on the
// laptop's CPU, so a few thousand notes is minutes of work. Doing that silently
// inside a normal start would look like the daemon hanging on boot. So the user
// runs it once, deliberately, after an embedder swap; the mismatch warning
// above tells them to. It re-embeds, logs what it did, and then the daemon
// carries on serving as usual — no separate binary, no second start needed.
func runReembed(dataStore *store.Store, emb router.Embedder, current string) {
	log.Printf("voice: re-embedding stored notes and facts with %s — this can take a few minutes, do not interrupt", current)
	res, err := dataStore.ReembedAll(context.Background(), current,
		// EmbedPassage, not EmbedQuery: these are stored texts being searched
		// FOR, which is the side they were written with.
		func(ctx context.Context, text string) ([]float32, error) {
			return router.EmbedPassage(ctx, emb, text)
		})
	if err != nil {
		log.Printf("voice: re-embed FAILED, nothing was changed and no marker was written — safe to run again: %v", err)
		return
	}
	if res.Skipped {
		log.Printf("voice: re-embed skipped — the stored vectors were already written by %s", current)
		return
	}
	log.Printf("voice: re-embed done — %d notes in the notes table, %d notes and %d facts in the memory index, took %s; stored vectors now belong to %s",
		res.Notes, res.MemNotes, res.Facts, res.Took.Round(time.Second), current)

	// A row with no text cannot be re-embedded, so its vector is still the old
	// model's noise while the marker now says everything is current. Both write
	// paths always store the text, so this should be zero — say it loudly
	// rather than bury it in the line above if it ever isn't.
	if res.NoText > 0 {
		log.Printf("voice: WARNING %d stored rows had no text, so their vectors could not be re-embedded and are still noise; they will never match anything useful (Vikunja #378)", res.NoText)
	}
}