package ctxmgr

import (
	"context"
	"errors"
	"strings"
	"testing"
	"time"
)

func TestSemanticSummary_FlagOffUnchanged(t *testing.T) {
	t.Cleanup(ResetSummaryFlagsForTest)
	SetSummaryFlagsForTest(SummaryFeatureFlags{Shadow: false, Replace: false})

	mgr := NewContextManager(nil, nil, DefaultTimeDecayConfig())
	mgr.SetSemanticSummarizer(&StubSemanticSummarizer{Narrative: "SHOULD_NOT_APPEAR"})
	ctx := context.Background()
	sessID := "sess_flag_off"

	batch := []ChatMessageRecord{
		{ID: 1, Role: "user", Content: "我们准备研发高频超声手术刀系统，请教立项建议", CreatedAt: time.Now()},
		{ID: 2, Role: "assistant", Content: "需关注电气安全。", CreatedAt: time.Now()},
	}
	sum, err := mgr.GenerateRollingSummary(ctx, sessID, nil, batch)
	if err != nil {
		t.Fatal(err)
	}
	if sum.Shadow != nil {
		t.Fatalf("flag off must not attach shadow: %+v", sum.Shadow)
	}
	if sum.FreshnessNote != "" {
		t.Fatalf("flag off must not set freshness: %q", sum.FreshnessNote)
	}
	if strings.Contains(sum.Narrative, "SHOULD_NOT_APPEAR") {
		t.Fatalf("stub narrative leaked into served narrative: %s", sum.Narrative)
	}
	if sum.Source != "deterministic" {
		t.Fatalf("source=%q want deterministic", sum.Source)
	}
}

func TestSemanticSummary_ShadowOKKeepsDeterministic(t *testing.T) {
	t.Cleanup(ResetSummaryFlagsForTest)
	SetSummaryFlagsForTest(SummaryFeatureFlags{Shadow: true, Replace: true}) // REPLACE env true but unwired

	mgr := NewContextManager(nil, nil, DefaultTimeDecayConfig())
	mgr.SetSemanticSummarizer(&StubSemanticSummarizer{Narrative: "语义影子叙事：超声刀立项"})
	ctx := context.Background()

	batch := []ChatMessageRecord{
		{ID: 1, Role: "user", Content: "我们准备研发高频超声手术刀系统，请教立项建议", CreatedAt: time.Now()},
		{ID: 2, Role: "assistant", Content: "超声手术设备属于二类或三类器械。", CreatedAt: time.Now()},
		{ID: 3, Role: "user", Content: "目标市场是国内及欧洲CE，项目预算大约在200万左右，型检周期通常需要多久？", CreatedAt: time.Now()},
	}
	sum, err := mgr.GenerateRollingSummary(ctx, "sess_shadow_ok", nil, batch)
	if err != nil {
		t.Fatal(err)
	}
	if sum.Shadow == nil {
		t.Fatal("expected advisory shadow attachment")
	}
	if strings.Contains(sum.Narrative, "语义影子叙事") {
		t.Fatalf("REPLACE must stay unwired; narrative replaced: %s", sum.Narrative)
	}
	if sum.Facts["device_type"] != "超声手术设备" {
		t.Fatalf("deterministic facts lost: %+v", sum.Facts)
	}
	// Production path is async: instant response is pending; drain / wait for OK.
	if sum.Shadow.Status == ShadowStatusPending {
		_ = mgr.DrainSemanticShadowTasks(ctx)
		if !mgr.WaitShadowIdle(2 * time.Second) {
			t.Fatal("shadow worker did not become idle")
		}
		sum, err = mgr.GetChatSummary(ctx, "sess_shadow_ok")
		if err != nil || sum == nil {
			t.Fatalf("get after drain: %v %+v", err, sum)
		}
	}
	if sum.Shadow == nil || sum.Shadow.Status != ShadowStatusOK {
		t.Fatalf("expected shadow ok after drain, got %+v", sum.Shadow)
	}
	if sum.Shadow.Narrative != "语义影子叙事：超声刀立项" {
		t.Fatalf("shadow narrative mismatch: %q", sum.Shadow.Narrative)
	}
	if sum.Shadow.ToolPermissions != SemanticToolPermissions {
		t.Fatalf("tool permissions=%q want none", sum.Shadow.ToolPermissions)
	}
	if sum.Shadow.InputDigest == "" {
		t.Fatal("missing input digest")
	}
	if strings.Contains(sum.Narrative, "语义影子叙事") {
		t.Fatalf("REPLACE must stay unwired after async attach: %s", sum.Narrative)
	}
	if sum.FreshnessNote != "" {
		t.Fatalf("ok path should clear freshness note: %q", sum.FreshnessNote)
	}
}

func TestSemanticSummary_ShadowFailureKeepsDeterministicWithFreshness(t *testing.T) {
	t.Cleanup(ResetSummaryFlagsForTest)
	SetSummaryFlagsForTest(SummaryFeatureFlags{Shadow: true})

	mgr := NewContextManager(nil, nil, DefaultTimeDecayConfig())
	mgr.SetSemanticSummarizer(&StubSemanticSummarizer{Err: errors.New("model timeout")})
	ctx := context.Background()

	batch := []ChatMessageRecord{
		{ID: 1, Role: "user", Content: "我们准备研发高频超声手术刀系统，请教立项建议", CreatedAt: time.Now()},
	}
	sum, err := mgr.GenerateRollingSummary(ctx, "sess_shadow_fail", nil, batch)
	if err != nil {
		t.Fatal(err)
	}
	if sum.Shadow == nil {
		t.Fatal("expected advisory shadow attachment")
	}
	if sum.Narrative == "" {
		t.Fatal("deterministic narrative must be retained")
	}
	if strings.Contains(sum.Narrative, "model timeout") {
		t.Fatal("error text must not pollute narrative")
	}
	if sum.Shadow.Status == ShadowStatusPending {
		_ = mgr.DrainSemanticShadowTasks(ctx)
		if !mgr.WaitShadowIdle(2 * time.Second) {
			t.Fatal("shadow worker did not become idle")
		}
		sum, err = mgr.GetChatSummary(ctx, "sess_shadow_fail")
		if err != nil || sum == nil {
			t.Fatalf("get after drain: %v %+v", err, sum)
		}
	}
	if sum.Shadow == nil || sum.Shadow.Status != ShadowStatusFallback {
		t.Fatalf("expected fallback shadow after drain, got %+v", sum.Shadow)
	}
	if sum.FreshnessNote == "" || !strings.Contains(sum.FreshnessNote, "deterministic retained") {
		t.Fatalf("expected freshness note, got %q", sum.FreshnessNote)
	}
}

func TestSemanticSummary_MinimizeDropsMetadataAndCaps(t *testing.T) {
	msgs := make([]ChatMessageRecord, 0, 50)
	for i := 1; i <= 50; i++ {
		msgs = append(msgs, ChatMessageRecord{
			ID:       int64(i),
			Role:     "user",
			Content:  strings.Repeat("字", 400) + " secret-meta",
			StageKey: "V1.0_quoting",
			Metadata: map[string]any{"stage_key": "V1.0_quoting", "token": "SECRET"},
		})
	}
	min := MinimizeAuthorizedMessages(msgs)
	if len(min) != semanticMaxMessages {
		t.Fatalf("len=%d want %d", len(min), semanticMaxMessages)
	}
	if min[0].ID != 11 {
		t.Fatalf("expected tail window start id=11, got %d", min[0].ID)
	}
	for _, m := range min {
		if utf8Count(m.Content) > semanticMaxContentRunes+3 { // truncateRunes appends "..."
			t.Fatalf("content not truncated: %d runes", utf8Count(m.Content))
		}
	}
	digest1 := DigestAuthorizedInput(min)
	digest2 := DigestAuthorizedInput(min)
	if digest1 == "" || digest1 != digest2 {
		t.Fatalf("digest unstable: %q vs %q", digest1, digest2)
	}
}

func utf8Count(s string) int {
	return len([]rune(s))
}

func TestDigestSemanticShadow_FlagOff(t *testing.T) {
	t.Cleanup(ResetSummaryFlagsForTest)
	SetSummaryFlagsForTest(SummaryFeatureFlags{Shadow: false})

	mgr := NewContextManager(nil, nil, DefaultTimeDecayConfig())
	mgr.SetSemanticSummarizer(&StubSemanticSummarizer{Narrative: "shadow-headline"})
	ctx := context.Background()
	day := time.Now().Format("2006-01-02")
	msgs := []ChatMessageRecord{
		{ID: 1, Role: "user", Content: "讨论立项", DayKey: day, CreatedAt: time.Now()},
	}
	d, err := mgr.GenerateDailyDigestFromMessages(ctx, "sess_d", day, msgs)
	if err != nil {
		t.Fatal(err)
	}
	if d.Shadow != nil || d.FreshnessNote != "" {
		t.Fatalf("flag off digest must omit shadow: %+v note=%q", d.Shadow, d.FreshnessNote)
	}
	if d.Source != "rule" {
		t.Fatalf("source=%q", d.Source)
	}
}

func TestDigestSemanticShadow_Fallback(t *testing.T) {
	t.Cleanup(ResetSummaryFlagsForTest)
	SetSummaryFlagsForTest(SummaryFeatureFlags{Shadow: true})

	mgr := NewContextManager(nil, nil, DefaultTimeDecayConfig())
	mgr.SetSemanticSummarizer(&StubSemanticSummarizer{Err: errors.New("boom")})
	ctx := context.Background()
	day := time.Now().Format("2006-01-02")
	msgs := []ChatMessageRecord{
		{ID: 1, Role: "user", Content: "讨论立项进度", DayKey: day, CreatedAt: time.Now()},
	}
	d, err := mgr.GenerateDailyDigestFromMessages(ctx, "sess_d2", day, msgs)
	if err != nil {
		t.Fatal(err)
	}
	headline := d.Headline
	if d.Shadow == nil || d.Shadow.Status != ShadowStatusFallback {
		t.Fatalf("want fallback shadow: %+v", d.Shadow)
	}
	if d.FreshnessNote == "" {
		t.Fatal("want freshness note")
	}
	if d.Headline != headline || d.Headline == "" {
		t.Fatal("deterministic headline must remain")
	}
}