// multitier — sophisticated multi-scenario load test mixing search,
// email/SMS validation, fill validation, profile swap, and playbook
// recording. Exercises the full Go substrate end-to-end at concurrency
// against a large workers corpus.
//
// Six scenario types (each ~simulates one coordinator workflow):
//   A. cold_search_email   — fresh demand → search → email outreach + validate
//   B. surge_fill_validate — multi-role surge → search × N → fill proposal + validate + record
//   C. profile_swap        — initial search → mid-session swap with ExcludeIDs
//   D. repeat_cache        — same query × 5 → measure warm-cache RPS pattern
//   E. sms_validate        — search → SMS draft (≤160 chars) → validate
//   F. playbook_record_replay — search → record → re-search with use_playbook=true
//
// Validators run IN-PROCESS via internal/validator (FillValidator +
// EmailValidator). Search/record go through Go gateway via HTTP.
//
// Usage:
//   multitier -gateway http://127.0.0.1:4110 \
//             -concurrency 50 -duration 5m
//
// Output: per-scenario success/failure counts, end-to-end latency
// histogram, validator pass/fail breakdown.
package main

import (
	"bytes"
	"encoding/json"
	"flag"
	"fmt"
	"io"
	"log"
	"math/rand"
	"net/http"
	"os"
	"sort"
	"strings"
	"sync"
	"sync/atomic"
	"time"

	"git.agentview.dev/profit/golangLAKEHOUSE/internal/validator"
)

// ── Scenario harness ──────────────────────────────────────────────

type scenarioResult struct {
	name      string
	success   bool
	failedAt  string // step that broke the workflow
	latency   time.Duration
	subSteps  []stepResult // per-step breakdown
	validator string       // "pass", "fail-policy", "fail-consistency", etc.
}

type stepResult struct {
	step    string
	latency time.Duration
	ok      bool
	err     string
}

type harness struct {
	gateway   string
	hc        *http.Client
	corpus    string // index name
	queryPool []map[string]any // generated queries
	workerPool []validator.WorkerRecord // pretend roster for validators
	emailVal  *validator.EmailValidator
	fillVal   *validator.FillValidator

	// Counters (atomic)
	scenarioRuns map[string]*int64
	scenarioFail map[string]*int64
	stepFail     map[string]*int64
	fillDebugCount int64
}

func newHarness(gateway string, corpus string) *harness {
	queryPool := buildQueryPool()
	workerPool := buildWorkerPool()
	lookup := validator.NewInMemoryWorkerLookup(workerPool)
	scenarios := []string{"cold_search_email", "surge_fill_validate", "profile_swap", "repeat_cache", "sms_validate", "playbook_record_replay"}
	runs := map[string]*int64{}
	fails := map[string]*int64{}
	for _, s := range scenarios {
		r := int64(0)
		f := int64(0)
		runs[s] = &r
		fails[s] = &f
	}
	return &harness{
		gateway:    gateway,
		hc:         &http.Client{Timeout: 60 * time.Second},
		corpus:     corpus,
		queryPool:  queryPool,
		workerPool: workerPool,
		emailVal:   validator.NewEmailValidator(lookup),
		fillVal:    validator.NewFillValidator(lookup),
		scenarioRuns: runs,
		scenarioFail: fails,
		stepFail:     map[string]*int64{},
	}
}

// buildQueryPool generates a mix of staffing-shape queries across
// roles, geos, clients. 30 queries to keep cache pressure realistic.
func buildQueryPool() []map[string]any {
	roles := []string{"Forklift Operator", "Pickers", "Loaders", "Warehouse Associate", "CNC Operator", "Shipping Clerk", "Packers"}
	cities := []struct {
		city, state string
	}{
		{"Detroit", "MI"}, {"Indianapolis", "IN"}, {"Aurora", "IL"},
		{"Joliet", "IL"}, {"Flint", "MI"}, {"Cleveland", "OH"},
		{"Fort Wayne", "IN"}, {"Kansas City", "MO"},
	}
	clients := []string{"Beacon Freight", "Midway Distribution", "Parallel Machining", "Heritage Foods", "Cornerstone Fabrication", "Pioneer Assembly"}
	out := []map[string]any{}
	for i := 0; i < 30; i++ {
		role := roles[i%len(roles)]
		c := cities[i%len(cities)]
		client := clients[i%len(clients)]
		count := 1 + (i % 5)
		out = append(out, map[string]any{
			"text":    fmt.Sprintf("Need %d %s in %s %s for %s", count, role, c.city, c.state, client),
			"role":    role,
			"city":    c.city,
			"state":   c.state,
			"client":  client,
			"count":   count,
		})
	}
	return out
}

// buildWorkerPool fabricates a small in-memory roster for validators.
// Real workers come from the parquet ingest; the validator's
// WorkerLookup needs a separate in-process source. Cross-runtime
// audit: the IDs used here (test-w-XXX) won't collide with the
// parquet's "w-XXX" prefix.
func buildWorkerPool() []validator.WorkerRecord {
	roles := []string{"Forklift Operator", "Pickers", "Loaders", "Warehouse Associate", "CNC Operator", "Shipping Clerk", "Packers"}
	cities := []struct{ city, state string }{
		{"Detroit", "MI"}, {"Indianapolis", "IN"}, {"Aurora", "IL"},
		{"Joliet", "IL"}, {"Flint", "MI"},
	}
	out := make([]validator.WorkerRecord, 0, 200)
	for i := 0; i < 200; i++ {
		role := roles[i%len(roles)]
		c := cities[i%len(cities)]
		out = append(out, validator.WorkerRecord{
			CandidateID: fmt.Sprintf("test-w-%03d", i),
			Name:        fmt.Sprintf("Worker %03d", i),
			Status:      "active",
			City:        ptr(c.city),
			State:       ptr(c.state),
			Role:        ptr(role),
		})
	}
	return out
}

func ptr(s string) *string { return &s }

// ── HTTP helpers ──────────────────────────────────────────────────

type matrixSearchReq struct {
	QueryText  string   `json:"query_text"`
	QueryRole  string   `json:"query_role,omitempty"`
	Corpora    []string `json:"corpora"`
	K          int      `json:"k"`
	PerCorpusK int      `json:"per_corpus_k"`
	UsePlaybook bool    `json:"use_playbook"`
	ExcludeIDs []string `json:"exclude_ids,omitempty"`
}

type matrixResult struct {
	ID       string          `json:"id"`
	Distance float32         `json:"distance"`
	Corpus   string          `json:"corpus"`
	Metadata json.RawMessage `json:"metadata,omitempty"`
}

type matrixResp struct {
	Results          []matrixResult `json:"results"`
	PlaybookBoosted  int            `json:"playbook_boosted,omitempty"`
	PlaybookInjected int            `json:"playbook_injected,omitempty"`
}

func (h *harness) matrixSearch(req matrixSearchReq) (*matrixResp, error) {
	body, _ := json.Marshal(req)
	httpReq, _ := http.NewRequest("POST", h.gateway+"/v1/matrix/search", bytes.NewReader(body))
	httpReq.Header.Set("Content-Type", "application/json")
	resp, err := h.hc.Do(httpReq)
	if err != nil {
		return nil, err
	}
	defer resp.Body.Close()
	if resp.StatusCode != 200 {
		bs, _ := io.ReadAll(resp.Body)
		return nil, fmt.Errorf("status %d: %s", resp.StatusCode, string(bs))
	}
	var out matrixResp
	if err := json.NewDecoder(resp.Body).Decode(&out); err != nil {
		return nil, err
	}
	return &out, nil
}

func (h *harness) playbookRecord(query, role, answerID, corpus string, score float64) error {
	body, _ := json.Marshal(map[string]any{
		"query_text":    query,
		"role":          role,
		"answer_id":     answerID,
		"answer_corpus": corpus,
		"score":         score,
		"tags":          []string{"multitier-loadtest"},
	})
	httpReq, _ := http.NewRequest("POST", h.gateway+"/v1/matrix/playbooks/record", bytes.NewReader(body))
	httpReq.Header.Set("Content-Type", "application/json")
	resp, err := h.hc.Do(httpReq)
	if err != nil {
		return err
	}
	defer resp.Body.Close()
	if resp.StatusCode != 200 {
		bs, _ := io.ReadAll(resp.Body)
		return fmt.Errorf("status %d: %s", resp.StatusCode, string(bs))
	}
	io.Copy(io.Discard, resp.Body)
	return nil
}

// ── Scenarios ─────────────────────────────────────────────────────

// timeStep wraps a closure with timing + step result.
func timeStep(name string, f func() error) stepResult {
	start := time.Now()
	err := f()
	r := stepResult{step: name, latency: time.Since(start), ok: err == nil}
	if err != nil {
		r.err = err.Error()
	}
	return r
}

// Scenario A: cold_search_email — fresh demand → search → email outreach + validate
func (h *harness) scenarioColdSearchEmail() scenarioResult {
	q := h.queryPool[rand.Intn(len(h.queryPool))]
	queryText := q["text"].(string)
	role := q["role"].(string)
	r := scenarioResult{name: "cold_search_email"}
	start := time.Now()

	// Step 1: search
	var resp *matrixResp
	r.subSteps = append(r.subSteps, timeStep("search", func() error {
		var err error
		resp, err = h.matrixSearch(matrixSearchReq{
			QueryText: queryText, QueryRole: role,
			Corpora: []string{h.corpus}, K: 5, PerCorpusK: 5,
		})
		return err
	}))
	if !r.subSteps[0].ok || resp == nil || len(resp.Results) == 0 {
		r.failedAt = "search"
		r.latency = time.Since(start)
		return r
	}

	// Step 2: pick top candidate, simulate email draft using a known
	// worker from our local pool (validator wants in-pool IDs).
	worker := h.workerPool[rand.Intn(len(h.workerPool))]
	emailDraft := map[string]any{
		"to":      "client@example.com",
		"subject": fmt.Sprintf("Worker available: %s", worker.Name),
		"body":    fmt.Sprintf("Hi, %s is available for the %s role tomorrow. Confirm?", worker.Name, role),
		"_context": map[string]any{"candidate_id": worker.CandidateID},
	}

	// Step 3: validate
	r.subSteps = append(r.subSteps, timeStep("email_validate", func() error {
		_, err := h.emailVal.Validate(validator.Artifact{EmailDraft: emailDraft})
		return err
	}))
	if !r.subSteps[1].ok {
		r.failedAt = "email_validate"
		r.validator = "fail"
		r.latency = time.Since(start)
		return r
	}

	r.success = true
	r.validator = "pass"
	r.latency = time.Since(start)
	return r
}

// Scenario B: surge_fill_validate — multi-role contract → multi-search → fill proposal → validate → record
func (h *harness) scenarioSurgeFillValidate() scenarioResult {
	q := h.queryPool[rand.Intn(len(h.queryPool))]
	role := q["role"].(string)
	city := q["city"].(string)
	state := q["state"].(string)
	r := scenarioResult{name: "surge_fill_validate"}
	start := time.Now()

	// Step 1: search × 1 (kept narrow to keep total latency reasonable)
	var resp *matrixResp
	r.subSteps = append(r.subSteps, timeStep("search", func() error {
		var err error
		resp, err = h.matrixSearch(matrixSearchReq{
			QueryText: q["text"].(string), QueryRole: role,
			Corpora: []string{h.corpus}, K: 3, PerCorpusK: 3,
		})
		return err
	}))
	if !r.subSteps[0].ok || resp == nil || len(resp.Results) == 0 {
		r.failedAt = "search"
		r.latency = time.Since(start)
		return r
	}

	// Step 2: build fill proposal — pick 2 workers that share city/state/role
	// to avoid spurious geo-mismatch errors. We loop the local pool from a
	// random offset and pick the first two with matching attributes.
	w1 := h.workerPool[rand.Intn(len(h.workerPool))]
	var w2 *validator.WorkerRecord
	// Linear scan from a random start offset — guarantees full pool
	// coverage even on small pools where matching pairs are rare.
	startOffset := rand.Intn(len(h.workerPool))
	for j := 0; j < len(h.workerPool); j++ {
		idx := (startOffset + j) % len(h.workerPool)
		w := h.workerPool[idx]
		if w.CandidateID == w1.CandidateID {
			continue
		}
		if w.City != nil && w1.City != nil && *w.City == *w1.City &&
			w.State != nil && w1.State != nil && *w.State == *w1.State &&
			w.Role != nil && w1.Role != nil && *w.Role == *w1.Role {
			wCopy := w // ensure address stays valid past loop end
			w2 = &wCopy
			break
		}
	}
	if w2 == nil {
		// Pool too sparse — should not happen with the 200-worker
		// fixture pool (35 unique combos × ~5 workers each). If we
		// hit this branch, the pool generator drifted; failing the
		// scenario is the right signal.
		r.failedAt = "no_matching_worker_pair"
		r.latency = time.Since(start)
		return r
	}
	city = *w1.City
	state = *w1.State
	role = *w1.Role
	fillProposal := map[string]any{
		"_context": map[string]any{
			"target_count": float64(2),
			"city":         city, "state": state, "role": role,
		},
		"fills": []any{
			map[string]any{"candidate_id": w1.CandidateID, "name": w1.Name},
			map[string]any{"candidate_id": w2.CandidateID, "name": w2.Name},
		},
	}

	// Step 3: validate fill
	var fillErr error
	r.subSteps = append(r.subSteps, timeStep("fill_validate", func() error {
		_, err := h.fillVal.Validate(validator.Artifact{FillProposal: fillProposal})
		fillErr = err
		return err
	}))
	if !r.subSteps[1].ok {
		// Print first error to stderr for diagnosis (rate-limited)
		if atomic.AddInt64(&h.fillDebugCount, 1) <= 3 && fillErr != nil {
			fmt.Fprintf(os.Stderr, "[debug] fill_validate err: %v\n  proposal=%+v\n", fillErr, fillProposal)
		}
		r.failedAt = "fill_validate"
		r.validator = "fail"
		r.latency = time.Since(start)
		return r
	}

	// Step 4: record playbook on first result
	r.subSteps = append(r.subSteps, timeStep("playbook_record", func() error {
		return h.playbookRecord(q["text"].(string), role, resp.Results[0].ID, h.corpus, 1.0)
	}))
	if !r.subSteps[2].ok {
		r.failedAt = "playbook_record"
		r.latency = time.Since(start)
		return r
	}

	r.success = true
	r.validator = "pass"
	r.latency = time.Since(start)
	return r
}

// Scenario C: profile_swap — initial search → mid-session swap with ExcludeIDs
func (h *harness) scenarioProfileSwap() scenarioResult {
	q := h.queryPool[rand.Intn(len(h.queryPool))]
	r := scenarioResult{name: "profile_swap"}
	start := time.Now()

	// Step 1: original search
	var resp1 *matrixResp
	r.subSteps = append(r.subSteps, timeStep("search_original", func() error {
		var err error
		resp1, err = h.matrixSearch(matrixSearchReq{
			QueryText: q["text"].(string), QueryRole: q["role"].(string),
			Corpora: []string{h.corpus}, K: 3, PerCorpusK: 3,
		})
		return err
	}))
	if !r.subSteps[0].ok || resp1 == nil || len(resp1.Results) == 0 {
		r.failedAt = "search_original"
		r.latency = time.Since(start)
		return r
	}

	// Capture placed IDs
	excludeIDs := make([]string, 0, len(resp1.Results))
	for _, x := range resp1.Results {
		excludeIDs = append(excludeIDs, x.ID)
	}

	// Step 2: swap search excluding the original placements
	var resp2 *matrixResp
	r.subSteps = append(r.subSteps, timeStep("search_swap", func() error {
		var err error
		resp2, err = h.matrixSearch(matrixSearchReq{
			QueryText: q["text"].(string), QueryRole: q["role"].(string),
			Corpora: []string{h.corpus}, K: 3, PerCorpusK: 3,
			ExcludeIDs: excludeIDs,
		})
		return err
	}))
	if !r.subSteps[1].ok || resp2 == nil {
		r.failedAt = "search_swap"
		r.latency = time.Since(start)
		return r
	}

	// Verify no overlap between original + swap
	overlap := false
	for _, a := range resp1.Results {
		for _, b := range resp2.Results {
			if a.ID == b.ID {
				overlap = true
				break
			}
		}
	}
	if overlap {
		r.failedAt = "swap_overlap_detected"
		r.latency = time.Since(start)
		return r
	}

	r.success = true
	r.latency = time.Since(start)
	return r
}

// Scenario D: repeat_cache — same query × 5 → measures cache effectiveness
func (h *harness) scenarioRepeatCache() scenarioResult {
	q := h.queryPool[rand.Intn(len(h.queryPool))]
	r := scenarioResult{name: "repeat_cache"}
	start := time.Now()

	for i := 0; i < 5; i++ {
		stepName := fmt.Sprintf("search_%d", i)
		var resp *matrixResp
		step := timeStep(stepName, func() error {
			var err error
			resp, err = h.matrixSearch(matrixSearchReq{
				QueryText: q["text"].(string), QueryRole: q["role"].(string),
				Corpora: []string{h.corpus}, K: 3, PerCorpusK: 3,
			})
			return err
		})
		r.subSteps = append(r.subSteps, step)
		if !step.ok || resp == nil {
			r.failedAt = stepName
			r.latency = time.Since(start)
			return r
		}
	}

	r.success = true
	r.latency = time.Since(start)
	return r
}

// Scenario E: sms_validate — SMS-shaped draft (≤160 chars), validate via
// EmailValidator with kind=sms. Catches the SMS-length cap + the
// SSN-pattern false-positive on phone numbers.
func (h *harness) scenarioSMSValidate() scenarioResult {
	q := h.queryPool[rand.Intn(len(h.queryPool))]
	worker := h.workerPool[rand.Intn(len(h.workerPool))]
	r := scenarioResult{name: "sms_validate"}
	start := time.Now()

	// Step 1: search
	r.subSteps = append(r.subSteps, timeStep("search", func() error {
		_, err := h.matrixSearch(matrixSearchReq{
			QueryText: q["text"].(string), QueryRole: q["role"].(string),
			Corpora: []string{h.corpus}, K: 1, PerCorpusK: 1,
		})
		return err
	}))
	if !r.subSteps[0].ok {
		r.failedAt = "search"
		r.latency = time.Since(start)
		return r
	}

	// Step 2: SMS draft (deliberately includes a phone number to
	// stress-test the SSN-pattern false-positive guard)
	smsDraft := map[string]any{
		"to":   "+15551234567",
		"body": fmt.Sprintf("%s confirmed for %s. Reply STOP to cancel. Call 555-123-4567.", worker.Name, q["role"].(string)),
		"kind": "sms",
		"_context": map[string]any{"candidate_id": worker.CandidateID},
	}

	// Step 3: validate
	r.subSteps = append(r.subSteps, timeStep("sms_validate", func() error {
		_, err := h.emailVal.Validate(validator.Artifact{EmailDraft: smsDraft})
		return err
	}))
	if !r.subSteps[1].ok {
		r.failedAt = "sms_validate"
		r.validator = "fail"
		r.latency = time.Since(start)
		return r
	}

	r.success = true
	r.validator = "pass"
	r.latency = time.Since(start)
	return r
}

// Scenario F: playbook_record_replay — search → record → re-search with
// use_playbook=true. Verifies the learning loop fires through real HTTP.
//
// Adds a unique suffix to query_text so concurrent goroutines don't
// race on the same playbook_memory entry (vectord HNSW Add has a
// concurrency edge case on small indexes; uniqueness avoids it).
func (h *harness) scenarioPlaybookRecordReplay() scenarioResult {
	q := h.queryPool[rand.Intn(len(h.queryPool))]
	role := q["role"].(string)
	queryText := fmt.Sprintf("%s [run-%d-%d]",
		q["text"].(string), time.Now().UnixNano(), rand.Intn(1000000))
	r := scenarioResult{name: "playbook_record_replay"}
	start := time.Now()

	// Step 1: cold search
	var resp1 *matrixResp
	r.subSteps = append(r.subSteps, timeStep("cold_search", func() error {
		var err error
		resp1, err = h.matrixSearch(matrixSearchReq{
			QueryText: queryText, QueryRole: role,
			Corpora: []string{h.corpus}, K: 3, PerCorpusK: 3,
		})
		return err
	}))
	if !r.subSteps[0].ok || resp1 == nil || len(resp1.Results) == 0 {
		r.failedAt = "cold_search"
		r.latency = time.Since(start)
		return r
	}

	// Step 2: record top-1 as playbook
	topID := resp1.Results[0].ID
	r.subSteps = append(r.subSteps, timeStep("playbook_record", func() error {
		return h.playbookRecord(queryText, role, topID, h.corpus, 1.0)
	}))
	if !r.subSteps[1].ok {
		r.failedAt = "playbook_record"
		r.latency = time.Since(start)
		return r
	}

	// Step 3: warm search with use_playbook=true
	r.subSteps = append(r.subSteps, timeStep("warm_search", func() error {
		_, err := h.matrixSearch(matrixSearchReq{
			QueryText: queryText, QueryRole: role,
			Corpora: []string{h.corpus}, K: 3, PerCorpusK: 3,
			UsePlaybook: true,
		})
		return err
	}))
	if !r.subSteps[2].ok {
		r.failedAt = "warm_search"
		r.latency = time.Since(start)
		return r
	}

	r.success = true
	r.latency = time.Since(start)
	return r
}

// pickScenario rolls a scenario based on a realistic workflow mix.
func (h *harness) pickScenario() func() scenarioResult {
	roll := rand.Intn(100)
	switch {
	case roll < 35: // 35% — fresh demand searches
		return h.scenarioColdSearchEmail
	case roll < 50: // 15% — surge fills with validation
		return h.scenarioSurgeFillValidate
	case roll < 65: // 15% — profile swaps
		return h.scenarioProfileSwap
	case roll < 80: // 15% — repeat queries (cache)
		return h.scenarioRepeatCache
	case roll < 90: // 10% — SMS drafts
		return h.scenarioSMSValidate
	default:        // 10% — playbook record + replay
		return h.scenarioPlaybookRecordReplay
	}
}

// ── Reporter ──────────────────────────────────────────────────────

type latStats struct {
	count     int
	sum       time.Duration
	latencies []time.Duration
}

func (s *latStats) add(d time.Duration) {
	s.count++
	s.sum += d
	s.latencies = append(s.latencies, d)
}
func (s *latStats) percentile(p float64) time.Duration {
	if len(s.latencies) == 0 {
		return 0
	}
	sort.Slice(s.latencies, func(i, j int) bool { return s.latencies[i] < s.latencies[j] })
	idx := int(p * float64(len(s.latencies)))
	if idx >= len(s.latencies) {
		idx = len(s.latencies) - 1
	}
	return s.latencies[idx]
}

// ── Main ──────────────────────────────────────────────────────────

func main() {
	gateway := flag.String("gateway", "http://127.0.0.1:4110", "Go gateway base URL")
	conc := flag.Int("concurrency", 50, "concurrent workers")
	dur := flag.Duration("duration", 5*time.Minute, "load duration")
	corpus := flag.String("corpus", "workers", "vectord index name")
	flag.Parse()

	rand.Seed(time.Now().UnixNano())
	h := newHarness(*gateway, *corpus)

	// Sanity: hit /v1/matrix/search once to verify the corpus is up.
	if _, err := h.matrixSearch(matrixSearchReq{
		QueryText: "test", Corpora: []string{*corpus}, K: 1, PerCorpusK: 1,
	}); err != nil {
		log.Fatalf("[multitier] sanity probe failed: %v\n  is the persistent stack up + workers ingested?", err)
	}

	results := make(chan scenarioResult, *conc*2)
	stop := make(chan struct{})
	var wg sync.WaitGroup
	var totalRuns int64

	for w := 0; w < *conc; w++ {
		wg.Add(1)
		go func() {
			defer wg.Done()
			for {
				select {
				case <-stop:
					return
				default:
				}
				fn := h.pickScenario()
				res := fn()
				results <- res
				atomic.AddInt64(&totalRuns, 1)
			}
		}()
	}

	// Reporter goroutine.
	all := []scenarioResult{}
	doneCollect := make(chan struct{})
	go func() {
		for r := range results {
			all = append(all, r)
		}
		close(doneCollect)
	}()

	log.Printf("[multitier] gateway=%s · concurrency=%d · duration=%v · corpus=%s",
		*gateway, *conc, *dur, *corpus)
	log.Printf("[multitier] scenarios: cold_search_email (35%%) · surge_fill (15%%) · swap (15%%) · repeat (15%%) · sms (10%%) · record_replay (10%%)")
	startWall := time.Now()
	time.Sleep(*dur)
	close(stop)
	wg.Wait()
	close(results)
	<-doneCollect
	wallElapsed := time.Since(startWall)

	report(all, wallElapsed, *conc)
}

func report(all []scenarioResult, wall time.Duration, concurrency int) {
	fmt.Printf("\n══ multitier load report ══\n")
	fmt.Printf("wall:          %v · concurrency=%d\n", wall.Round(time.Millisecond), concurrency)
	fmt.Printf("total scenarios: %d (%.1f/sec)\n", len(all), float64(len(all))/wall.Seconds())
	if len(all) == 0 {
		return
	}

	// Per-scenario breakdown
	type scStats struct {
		name      string
		runs      int
		fails     int
		validator map[string]int
		failedAt  map[string]int
		lat       latStats
	}
	bucket := map[string]*scStats{}
	for _, r := range all {
		s, ok := bucket[r.name]
		if !ok {
			s = &scStats{name: r.name, validator: map[string]int{}, failedAt: map[string]int{}}
			bucket[r.name] = s
		}
		s.runs++
		s.lat.add(r.latency)
		if !r.success {
			s.fails++
			if r.failedAt != "" {
				s.failedAt[r.failedAt]++
			}
		}
		if r.validator != "" {
			s.validator[r.validator]++
		}
	}

	// Print per-scenario table
	names := []string{"cold_search_email", "surge_fill_validate", "profile_swap", "repeat_cache", "sms_validate", "playbook_record_replay"}
	fmt.Println()
	fmt.Printf("%-26s %8s %7s %8s %8s %8s %8s\n",
		"scenario", "runs", "fail%", "p50", "p95", "p99", "max")
	for _, n := range names {
		s, ok := bucket[n]
		if !ok {
			continue
		}
		failPct := 100 * float64(s.fails) / float64(s.runs)
		fmt.Printf("%-26s %8d %6.1f%% %8v %8v %8v %8v\n",
			n, s.runs, failPct,
			s.lat.percentile(0.50).Round(time.Microsecond),
			s.lat.percentile(0.95).Round(time.Microsecond),
			s.lat.percentile(0.99).Round(time.Microsecond),
			s.lat.percentile(1.00).Round(time.Microsecond),
		)
	}

	// Failure breakdown
	totalFails := 0
	for _, s := range bucket {
		totalFails += s.fails
	}
	if totalFails > 0 {
		fmt.Println("\n── failure-step breakdown ──")
		for _, n := range names {
			s, ok := bucket[n]
			if !ok || s.fails == 0 {
				continue
			}
			fmt.Printf("  %s:\n", n)
			for step, count := range s.failedAt {
				fmt.Printf("    %s: %d\n", step, count)
			}
		}
	}

	// Validator pass/fail
	fmt.Println("\n── validator outcomes ──")
	for _, n := range names {
		s, ok := bucket[n]
		if !ok || len(s.validator) == 0 {
			continue
		}
		var keys []string
		for k := range s.validator {
			keys = append(keys, k)
		}
		sort.Strings(keys)
		var parts []string
		for _, k := range keys {
			parts = append(parts, fmt.Sprintf("%s=%d", k, s.validator[k]))
		}
		fmt.Printf("  %-26s %s\n", n, strings.Join(parts, " · "))
	}

	// JSON summary on stderr for parsability
	type summary struct {
		WallSec  float64        `json:"wall_sec"`
		Total    int            `json:"total_scenarios"`
		Failures int            `json:"failures"`
		PerScenario map[string]struct {
			Runs   int     `json:"runs"`
			Fails  int     `json:"fails"`
			P50Ms  float64 `json:"p50_ms"`
			P99Ms  float64 `json:"p99_ms"`
		} `json:"per_scenario"`
	}
	s := summary{
		WallSec: wall.Seconds(), Total: len(all), Failures: totalFails,
		PerScenario: map[string]struct {
			Runs   int     `json:"runs"`
			Fails  int     `json:"fails"`
			P50Ms  float64 `json:"p50_ms"`
			P99Ms  float64 `json:"p99_ms"`
		}{},
	}
	for _, n := range names {
		st, ok := bucket[n]
		if !ok {
			continue
		}
		s.PerScenario[n] = struct {
			Runs   int     `json:"runs"`
			Fails  int     `json:"fails"`
			P50Ms  float64 `json:"p50_ms"`
			P99Ms  float64 `json:"p99_ms"`
		}{
			Runs: st.runs, Fails: st.fails,
			P50Ms: float64(st.lat.percentile(0.50).Microseconds()) / 1000,
			P99Ms: float64(st.lat.percentile(0.99).Microseconds()) / 1000,
		}
	}
	enc, _ := json.MarshalIndent(s, "", "  ")
	fmt.Fprintf(os.Stderr, "\n%s\n", enc)
}