package service

import (
	"context"
	"fmt"
	"testing"
	"time"

	"github.com/Tencent/WeKnora/internal/application/repository"
	"github.com/Tencent/WeKnora/internal/types"
	"github.com/google/uuid"
	"github.com/stretchr/testify/require"
	"gorm.io/driver/sqlite"
	"gorm.io/gorm"
)

func TestPruneEmptyFolderChainsDeletesOnlyEmptyCandidateAncestors(t *testing.T) {
	db, err := gorm.Open(sqlite.Open(fmt.Sprintf("file:%s?mode=memory&cache=shared", t.Name())), &gorm.Config{})
	require.NoError(t, err)
	require.NoError(t, db.AutoMigrate(&types.WikiFolder{}, &types.WikiPage{}, &types.WikiPageRevision{}))

	ctx := context.Background()
	repo := repository.NewWikiPageRepository(db)
	svc := NewWikiPageService(repo, nil, nil, nil, nil)
	now := time.Now()
	createFolder := func(id, parentID, name, path string, depth int) {
		require.NoError(t, repo.CreateFolder(ctx, &types.WikiFolder{
			ID: id, TenantID: 1, KnowledgeBaseID: "kb-prune", ParentID: parentID,
			Name: name, Path: path, Depth: depth, CreatedAt: now, UpdatedAt: now,
		}))
	}
	createFolder("topic", "", "Topic", "Topic", 1)
	createFolder("empty-leaf", "topic", "Empty", "Topic/Empty", 2)
	createFolder("occupied-leaf", "topic", "Occupied", "Topic/Occupied", 2)
	createFolder("empty-chain", "", "Empty chain", "Empty chain", 1)
	createFolder("empty-chain-leaf", "empty-chain", "Leaf", "Empty chain/Leaf", 2)
	createFolder("unrelated-empty", "", "Keep me", "Keep me", 1)

	require.NoError(t, repo.Create(ctx, &types.WikiPage{
		ID: "page-1", TenantID: 1, KnowledgeBaseID: "kb-prune", Slug: "entity/occupied",
		Title: "Occupied", PageType: types.WikiPageTypeEntity, Status: types.WikiPageStatusPublished,
		FolderID: "occupied-leaf", Version: 1, CreatedAt: now, UpdatedAt: now,
	}))

	deleted, err := svc.PruneEmptyFolderChains(ctx, "kb-prune", []string{"empty-leaf", "empty-chain-leaf"})
	require.NoError(t, err)
	require.ElementsMatch(t, []string{"empty-leaf", "empty-chain-leaf", "empty-chain"}, deleted)

	_, err = repo.GetFolderByID(ctx, "kb-prune", "topic")
	require.NoError(t, err, "ancestor with another occupied child must remain")
	_, err = repo.GetFolderByID(ctx, "kb-prune", "occupied-leaf")
	require.NoError(t, err)
	_, err = repo.GetFolderByID(ctx, "kb-prune", "unrelated-empty")
	require.NoError(t, err, "empty folders outside the affected chains must remain")
}

func TestStripWikiInlineChunkCitations(t *testing.T) {
	input := "[**橡皮障夹**](#)**钳**\n\n夹钳是用于夹持橡皮障夹的专用器械[c003]。手柄便于操作 [c003]。多个来源[c003, c1000]。"
	want := "[**橡皮障夹**](#)**钳**\n\n夹钳是用于夹持橡皮障夹的专用器械。手柄便于操作。多个来源。"

	if got := stripWikiInlineChunkCitations(input); got != want {
		t.Fatalf("stripWikiInlineChunkCitations() = %q, want %q", got, want)
	}
}

func TestStripWikiInlineChunkCitationsPreservesOrdinaryMarkdown(t *testing.T) {
	input := "保留 [citation]、[C003]、[c12] 和 [[concept/c003|页面链接]]。"
	if got := stripWikiInlineChunkCitations(input); got != input {
		t.Fatalf("stripWikiInlineChunkCitations() changed ordinary Markdown: %q", got)
	}
}

func TestUpdateWikiPagePersistsAndClearsAliases(t *testing.T) {
	db, err := gorm.Open(sqlite.Open(fmt.Sprintf("file:%s?mode=memory&cache=shared", t.Name())), &gorm.Config{})
	require.NoError(t, err)
	require.NoError(t, db.AutoMigrate(&types.WikiFolder{}, &types.WikiPage{}, &types.WikiPageRevision{}))

	ctx := context.Background()
	repo := repository.NewWikiPageRepository(db)
	svc := NewWikiPageService(repo, nil, nil, nil, nil)
	page, err := svc.CreatePage(ctx, &types.WikiPage{
		TenantID: 1, KnowledgeBaseID: "kb-alias", Slug: "concept/alias",
		Title: "Alias", Summary: "summary", Content: "content",
		PageType: types.WikiPageTypeConcept, Aliases: types.StringArray{"old"},
	})
	require.NoError(t, err)

	page.Aliases = types.StringArray{"new", "alternate"}
	updated, err := svc.UpdatePage(ctx, page)
	require.NoError(t, err)
	require.Equal(t, types.StringArray{"new", "alternate"}, updated.Aliases)
	require.Equal(t, 2, updated.Version)

	updated.Aliases = types.StringArray{}
	cleared, err := svc.UpdatePage(ctx, updated)
	require.NoError(t, err)
	require.Empty(t, cleared.Aliases)
	require.Equal(t, 3, cleared.Version)

	stored, err := svc.GetPageBySlug(ctx, "kb-alias", "concept/alias")
	require.NoError(t, err)
	require.Empty(t, stored.Aliases)
}

func TestParseOutLinks(t *testing.T) {
	svc := &wikiPageService{}

	tests := []struct {
		name    string
		content string
		want    []string
	}{
		{
			name:    "single link",
			content: "See [[entity/acme-corp]] for details.",
			want:    []string{"entity/acme-corp"},
		},
		{
			name:    "multiple links",
			content: "See [[entity/acme-corp]] and [[concept/rag]] for details.",
			want:    []string{"entity/acme-corp", "concept/rag"},
		},
		{
			name:    "duplicate links deduplicated",
			content: "See [[entity/acme-corp]] and also [[entity/acme-corp]] again.",
			want:    []string{"entity/acme-corp"},
		},
		{
			name:    "pipe syntax: slug|display name",
			content: "See [[entity/acme-corp|Acme Corp]] for details.",
			want:    []string{"entity/acme-corp"},
		},
		{
			name:    "mixed: pipe and bare links",
			content: "See [[entity/acme-corp|Acme Corp]] and [[concept/rag]] here.",
			want:    []string{"entity/acme-corp", "concept/rag"},
		},
		{
			name:    "no links",
			content: "Just plain text without any links.",
			want:    nil,
		},
		{
			name:    "empty content",
			content: "",
			want:    nil,
		},
		{
			name:    "link with spaces normalized",
			content: "See [[Entity/Acme Corp]] for details.",
			want:    []string{"entity/acme-corp"},
		},
		{
			name:    "nested brackets ignored",
			content: "Not a link: [not [a] link]",
			want:    nil,
		},
	}

	for _, tt := range tests {
		t.Run(tt.name, func(t *testing.T) {
			got := svc.parseOutLinks(tt.content)
			if len(got) != len(tt.want) {
				t.Errorf("parseOutLinks() = %v (len %d), want %v (len %d)", got, len(got), tt.want, len(tt.want))
				return
			}
			for i := range got {
				if got[i] != tt.want[i] {
					t.Errorf("parseOutLinks()[%d] = %q, want %q", i, got[i], tt.want[i])
				}
			}
		})
	}
}

func TestRepairContentLinks(t *testing.T) {
	db, err := gorm.Open(sqlite.Open(fmt.Sprintf("file:%s?mode=memory&cache=shared", t.Name())), &gorm.Config{})
	require.NoError(t, err)
	require.NoError(t, db.AutoMigrate(&types.WikiFolder{}, &types.WikiPage{}, &types.WikiPageRevision{}))

	ctx := context.Background()
	repo := repository.NewWikiPageRepository(db)
	svc := NewWikiPageService(repo, nil, nil, nil, nil)
	const kbID = "kb-repair"
	now := time.Now()

	seed := func(slug, title, pageType string) {
		require.NoError(t, repo.Create(ctx, &types.WikiPage{
			ID: uuid.New().String(), TenantID: 1, KnowledgeBaseID: kbID,
			Slug: slug, Title: title, PageType: pageType,
			Status: types.WikiPageStatusPublished, Version: 1,
			CreatedAt: now, UpdatedAt: now,
		}))
	}

	// Real summary page (clean UUID slug) + a distractor summary + an entity.
	realSummary := "summary/07a20bb1-a662-47cf-9929-06fb5d5b5b5e"
	seed(realSummary, "Weknora 试错记录.md - Summary", types.WikiPageTypeSummary)
	seed("summary/fcadcaab-e094-4037-b71c-9edfdcdba058", "Another Doc - Summary", types.WikiPageTypeSummary)
	seed("entity/mongodb", "MongoDB", types.WikiPageTypeEntity)

	t.Run("mangled uuid summary link repaired via bigram", func(t *testing.T) {
		// One hex digit inserted into the last group — 404s on exact lookup.
		content := "See [[summary/07a20bb1-a662-47cf-9929-06fb14d5b14b14e|Weknora 试错记录.md - Summary]] for context."
		got, changed, err := svc.RepairContentLinks(ctx, kbID, "synthesis/notes", content)
		require.NoError(t, err)
		require.True(t, changed, "expected the mangled summary link to be rewritten")
		require.Contains(t, got, "[["+realSummary+"|Weknora 试错记录.md - Summary]]")
		require.NotContains(t, got, "06fb14d5b14b14e")
	})

	t.Run("live links untouched", func(t *testing.T) {
		content := "Fine: [[entity/mongodb]] and [[" + realSummary + "]]."
		got, changed, err := svc.RepairContentLinks(ctx, kbID, "synthesis/notes", content)
		require.NoError(t, err)
		require.False(t, changed)
		require.Equal(t, content, got)
	})

	t.Run("unresolvable dead link left as-is, never stripped", func(t *testing.T) {
		// A future entity page that doesn't exist and isn't similar to anything.
		content := "Pending: [[entity/some-brand-new-topic|New Topic]]."
		got, changed, err := svc.RepairContentLinks(ctx, kbID, "synthesis/notes", content)
		require.NoError(t, err)
		require.False(t, changed)
		require.Equal(t, content, got, "unresolvable links must be preserved verbatim, not stripped")
	})
}

func TestNormalizeSlug(t *testing.T) {
	tests := []struct {
		input string
		want  string
	}{
		{"Entity/Acme Corp", "entity/acme-corp"},
		{"  hello  ", "hello"},
		{"UPPER-CASE", "upper-case"},
		{"already-ok", "already-ok"},
		{"", ""},
	}

	for _, tt := range tests {
		t.Run(tt.input, func(t *testing.T) {
			got := normalizeSlug(tt.input)
			if got != tt.want {
				t.Errorf("normalizeSlug(%q) = %q, want %q", tt.input, got, tt.want)
			}
		})
	}
}

func TestNormalizeWikiHierarchyCleansModelCategoryNoise(t *testing.T) {
	page := &types.WikiPage{
		Slug:         "concept/ai-knowledge",
		Title:        "AI时代的知识困境",
		PageType:     types.WikiPageTypeConcept,
		CategoryPath: types.StringArray{"概念/爱护花草", " 实体/标牌 ", "摘要", "生态/平台", "多余层级"},
	}

	normalizeWikiHierarchy(page)

	want := types.StringArray{"爱护花草", "标牌", "生态"}
	if len(page.CategoryPath) != len(want) {
		t.Fatalf("CategoryPath = %v, want %v", page.CategoryPath, want)
	}
	for i := range want {
		if page.CategoryPath[i] != want[i] {
			t.Fatalf("CategoryPath[%d] = %q, want %q; full path=%v", i, page.CategoryPath[i], want[i], page.CategoryPath)
		}
	}
	if page.Depth != 3 {
		t.Fatalf("Depth = %d, want 3", page.Depth)
	}
	if page.WikiPath != "concept/爱护花草/标牌/生态/AI时代的知识困境" {
		t.Fatalf("WikiPath = %q", page.WikiPath)
	}
}

func TestNormalizeWikiIndexEntryHierarchyCleansModelCategoryNoise(t *testing.T) {
	entry := &types.WikiIndexEntry{
		Slug:         "entity/sign",
		Title:        "爱护花草标牌",
		CategoryPath: types.StringArray{"实体/标牌", "概念", "生态/行为倡导"},
	}

	normalizeWikiIndexEntryHierarchy(entry, types.WikiPageTypeEntity)

	want := types.StringArray{"标牌", "生态", "行为倡导"}
	if len(entry.CategoryPath) != len(want) {
		t.Fatalf("CategoryPath = %v, want %v", entry.CategoryPath, want)
	}
	for i := range want {
		if entry.CategoryPath[i] != want[i] {
			t.Fatalf("CategoryPath[%d] = %q, want %q; full path=%v", i, entry.CategoryPath[i], want[i], entry.CategoryPath)
		}
	}
	if entry.WikiPath != "entity/标牌/生态/行为倡导/爱护花草标牌" {
		t.Fatalf("WikiPath = %q", entry.WikiPath)
	}
}

func TestContainsString(t *testing.T) {
	slice := []string{"a", "b", "c"}
	if !containsString(slice, "b") {
		t.Error("should contain 'b'")
	}
	if containsString(slice, "d") {
		t.Error("should not contain 'd'")
	}
	if containsString(nil, "a") {
		t.Error("nil slice should not contain anything")
	}
}

func TestRemoveString(t *testing.T) {
	slice := types.StringArray{"a", "b", "c", "b"}
	result := removeString(slice, "b")
	if len(result) != 2 {
		t.Errorf("Expected 2 items after removing 'b', got %d: %v", len(result), result)
	}
	if result[0] != "a" || result[1] != "c" {
		t.Errorf("Unexpected result: %v", result)
	}

	// Remove non-existing
	result2 := removeString(slice, "z")
	if len(result2) != 4 {
		t.Errorf("Expected 4 items (nothing removed), got %d", len(result2))
	}
}

// makeGraphFixture builds a small synthetic wiki for GetGraph tests.
//
// Edges (directed):
//
//	hub -> a, hub -> b, hub -> c, hub -> d
//	a   -> hub
//	b   -> hub
//	c   -> d
//	x   -> y   (isolated 2-node cluster, disconnected from hub)
//
// Page types are chosen so type-filter tests can exclude specific nodes.
func makeGraphFixture() []*types.WikiPage {
	return []*types.WikiPage{
		{
			Slug:     "hub",
			Title:    "Hub",
			PageType: types.WikiPageTypeSummary,
			OutLinks: types.StringArray{"a", "b", "c", "d"},
			InLinks:  types.StringArray{"a", "b"},
		},
		{
			Slug:     "a",
			Title:    "A",
			PageType: types.WikiPageTypeEntity,
			OutLinks: types.StringArray{"hub"},
			InLinks:  types.StringArray{"hub"},
		},
		{
			Slug:     "b",
			Title:    "B",
			PageType: types.WikiPageTypeEntity,
			OutLinks: types.StringArray{"hub"},
			InLinks:  types.StringArray{"hub"},
		},
		{
			Slug:     "c",
			Title:    "C",
			PageType: types.WikiPageTypeConcept,
			OutLinks: types.StringArray{"d"},
			InLinks:  types.StringArray{"hub"},
		},
		{
			Slug:     "d",
			Title:    "D",
			PageType: types.WikiPageTypeConcept,
			OutLinks: types.StringArray{},
			InLinks:  types.StringArray{"hub", "c"},
		},
		{
			Slug:     "x",
			Title:    "X",
			PageType: types.WikiPageTypeEntity,
			OutLinks: types.StringArray{"y"},
			InLinks:  types.StringArray{},
		},
		{
			Slug:     "y",
			Title:    "Y",
			PageType: types.WikiPageTypeEntity,
			OutLinks: types.StringArray{},
			InLinks:  types.StringArray{"x"},
		},
	}
}

func nodeSlugs(data *types.WikiGraphData) map[string]bool {
	out := make(map[string]bool, len(data.Nodes))
	for _, n := range data.Nodes {
		out[n.Slug] = true
	}
	return out
}

// TestComputeGraphSubset_OverviewTruncatesByLinkCount verifies that overview
// mode returns the most-connected nodes first and reports truncation
// honestly in Meta. At 4万 pages this is the path that must NOT return the
// full graph — the cap is what keeps the response size and frontend
// rendering tractable.
func TestComputeGraphSubset_OverviewTruncatesByLinkCount(t *testing.T) {
	pages := makeGraphFixture()
	got, err := computeGraphSubset(pages, &types.WikiGraphRequest{
		Mode:  types.WikiGraphModeOverview,
		Limit: 3,
	})
	if err != nil {
		t.Fatalf("computeGraphSubset: %v", err)
	}

	if len(got.Nodes) != 3 {
		t.Errorf("want 3 nodes, got %d (%v)", len(got.Nodes), nodeSlugs(got))
	}
	slugs := nodeSlugs(got)
	// hub has link_count 6 (4 out + 2 in), must survive the cap.
	if !slugs["hub"] {
		t.Errorf("expected hub to survive the top-3 cap, got %v", slugs)
	}
	if !got.Meta.Truncated {
		t.Errorf("expected Meta.Truncated=true when returned < total")
	}
	if got.Meta.Total != len(pages) {
		t.Errorf("Meta.Total = %d, want %d", got.Meta.Total, len(pages))
	}
	if got.Meta.Returned != len(got.Nodes) {
		t.Errorf("Meta.Returned mismatch: %d vs %d", got.Meta.Returned, len(got.Nodes))
	}

	// Every returned edge must connect two surviving nodes.
	for _, e := range got.Edges {
		if !slugs[e.Source] || !slugs[e.Target] {
			t.Errorf("edge %s->%s references a non-returned node", e.Source, e.Target)
		}
	}
}

func TestComputeGraphSubset_MarksFamiliarSourcePages(t *testing.T) {
	pages := makeGraphFixture()
	pages[0].SourceRefs = types.StringArray{"doc-1|排班手册"}
	pages[1].SourceRefs = types.StringArray{"doc-2"}

	got, err := computeGraphSubset(pages, &types.WikiGraphRequest{
		Mode:                 types.WikiGraphModeOverview,
		Limit:                0,
		FamiliarKnowledgeIDs: []string{"doc-1"},
	})
	if err != nil {
		t.Fatalf("computeGraphSubset: %v", err)
	}
	familiar := map[string]bool{}
	for _, n := range got.Nodes {
		if n.Familiar {
			familiar[n.Slug] = true
		}
	}
	if !familiar["hub"] {
		t.Errorf("hub sources doc-1, want familiar, got %v", familiar)
	}
	if familiar["a"] {
		t.Errorf("a sources a different document, must not light up")
	}
	if got.Meta.FamiliarCount != 1 {
		t.Errorf("FamiliarCount = %d, want 1", got.Meta.FamiliarCount)
	}
}

// TestComputeGraphSubset_OverviewUncapped ensures the Limit<=0 escape hatch
// still works for internal callers (wiki lint) that need every page.
func TestComputeGraphSubset_OverviewUncapped(t *testing.T) {
	pages := makeGraphFixture()
	got, err := computeGraphSubset(pages, &types.WikiGraphRequest{
		Mode:  types.WikiGraphModeOverview,
		Limit: 0,
	})
	if err != nil {
		t.Fatalf("computeGraphSubset: %v", err)
	}
	if len(got.Nodes) != len(pages) {
		t.Errorf("want %d nodes (uncapped), got %d", len(pages), len(got.Nodes))
	}
	if got.Meta.Truncated {
		t.Errorf("expected Meta.Truncated=false when nothing was dropped")
	}
}

// TestComputeGraphSubset_OverviewTypeFilter ensures the type filter applies
// to the candidate set (not just post-hoc), so "total" reflects the
// filter-aware denominator the frontend shows to the user.
func TestComputeGraphSubset_OverviewTypeFilter(t *testing.T) {
	pages := makeGraphFixture()
	got, err := computeGraphSubset(pages, &types.WikiGraphRequest{
		Mode:  types.WikiGraphModeOverview,
		Types: []string{types.WikiPageTypeEntity},
		Limit: 100,
	})
	if err != nil {
		t.Fatalf("computeGraphSubset: %v", err)
	}
	slugs := nodeSlugs(got)
	// Only entity-typed pages: a, b, x, y.
	for _, expected := range []string{"a", "b", "x", "y"} {
		if !slugs[expected] {
			t.Errorf("expected entity %q to be returned, got %v", expected, slugs)
		}
	}
	for _, forbidden := range []string{"hub", "c", "d"} {
		if slugs[forbidden] {
			t.Errorf("%q should have been filtered out by type, got %v", forbidden, slugs)
		}
	}
	if got.Meta.Total != 4 {
		t.Errorf("Meta.Total should equal entity-typed page count (4), got %d", got.Meta.Total)
	}
}

// TestComputeGraphSubset_EgoDepth1 checks that depth=1 returns center +
// immediate neighbors only, with no transitive hops.
func TestComputeGraphSubset_EgoDepth1(t *testing.T) {
	pages := makeGraphFixture()
	got, err := computeGraphSubset(pages, &types.WikiGraphRequest{
		Mode:   types.WikiGraphModeEgo,
		Center: "hub",
		Depth:  1,
		Limit:  100,
	})
	if err != nil {
		t.Fatalf("computeGraphSubset: %v", err)
	}
	slugs := nodeSlugs(got)
	// hub's direct neighbors: a, b, c, d (out) ∪ a, b (in) = {a, b, c, d} + hub.
	want := []string{"hub", "a", "b", "c", "d"}
	for _, s := range want {
		if !slugs[s] {
			t.Errorf("expected %q in ego depth=1 of hub, got %v", s, slugs)
		}
	}
	// x and y are in a disconnected cluster and must not leak in.
	if slugs["x"] || slugs["y"] {
		t.Errorf("disconnected nodes leaked into ego graph: %v", slugs)
	}
	if got.Meta.Mode != types.WikiGraphModeEgo || got.Meta.Center != "hub" || got.Meta.Depth != 1 {
		t.Errorf("Meta not populated correctly for ego: %+v", got.Meta)
	}
}

// TestComputeGraphSubset_EgoDepth2 checks that an extra hop reaches pages
// only accessible through a one-hop neighbor (c -> d becomes reachable from
// "a" at depth 2 because a -> hub -> c -> d ... wait, that's 3 hops. Use
// a clearer case: from "a", depth=2 should reach hub's neighbors.)
func TestComputeGraphSubset_EgoDepth2ExpandsFrontier(t *testing.T) {
	pages := makeGraphFixture()
	depth1, err := computeGraphSubset(pages, &types.WikiGraphRequest{
		Mode:   types.WikiGraphModeEgo,
		Center: "a",
		Depth:  1,
		Limit:  100,
	})
	if err != nil {
		t.Fatalf("depth=1: %v", err)
	}
	depth2, err := computeGraphSubset(pages, &types.WikiGraphRequest{
		Mode:   types.WikiGraphModeEgo,
		Center: "a",
		Depth:  2,
		Limit:  100,
	})
	if err != nil {
		t.Fatalf("depth=2: %v", err)
	}
	if len(depth2.Nodes) <= len(depth1.Nodes) {
		t.Errorf("depth=2 should expand the frontier beyond depth=1 (%d <= %d)",
			len(depth2.Nodes), len(depth1.Nodes))
	}
	// At depth 2 from "a": a -> hub -> {b, c, d}. So b, c, d must appear.
	slugs := nodeSlugs(depth2)
	for _, s := range []string{"a", "hub", "b", "c", "d"} {
		if !slugs[s] {
			t.Errorf("expected %q at depth=2 from a, got %v", s, slugs)
		}
	}
}

// TestComputeGraphSubset_EgoRejectsMissingCenter ensures we fail fast
// rather than returning an empty graph when the caller points at a
// non-existent slug — an empty result here would look identical to "your
// wiki has no links to that page" and hide the real bug.
func TestComputeGraphSubset_EgoRejectsMissingCenter(t *testing.T) {
	pages := makeGraphFixture()
	_, err := computeGraphSubset(pages, &types.WikiGraphRequest{
		Mode:   types.WikiGraphModeEgo,
		Center: "does-not-exist",
		Depth:  1,
		Limit:  100,
	})
	if err == nil {
		t.Fatalf("expected error for missing center slug")
	}
}

func TestFindPagesByNormalizedTitleMatchesWhitespace(t *testing.T) {
	db, err := gorm.Open(sqlite.Open(fmt.Sprintf("file:%s?mode=memory&cache=shared", t.Name())), &gorm.Config{})
	require.NoError(t, err)
	require.NoError(t, db.AutoMigrate(&types.WikiFolder{}, &types.WikiPage{}, &types.WikiPageRevision{}))

	ctx := context.Background()
	repo := repository.NewWikiPageRepository(db)
	svc := NewWikiPageService(repo, nil, nil, nil, nil)
	now := time.Now()
	require.NoError(t, repo.Create(ctx, &types.WikiPage{
		ID: "page-kong", TenantID: 1, KnowledgeBaseID: "kb-id", Slug: "entity/confucius",
		Title: "孔 子", PageType: types.WikiPageTypeEntity, Status: types.WikiPageStatusPublished,
		Version: 1, CreatedAt: now, UpdatedAt: now,
	}))
	require.NoError(t, repo.Create(ctx, &types.WikiPage{
		ID: "page-fable", TenantID: 1, KnowledgeBaseID: "kb-id", Slug: "concept/yuyan",
		Title: "《寓言》", PageType: types.WikiPageTypeConcept, Status: types.WikiPageStatusPublished,
		Version: 1, CreatedAt: now, UpdatedAt: now,
	}))

	pages, err := svc.FindPagesByNormalizedTitle(ctx, "kb-id", types.WikiPageTypeEntity, "孔子")
	require.NoError(t, err)
	require.Len(t, pages, 1)
	require.Equal(t, "entity/confucius", pages[0].Slug)

	none, err := svc.FindPagesByNormalizedTitle(ctx, "kb-id", types.WikiPageTypeConcept, "寓言")
	require.NoError(t, err)
	require.Empty(t, none, "punctuation-significant titles must stay distinct")

	require.NoError(t, repo.Create(ctx, &types.WikiPage{
		ID: "page-mencius", TenantID: 1, KnowledgeBaseID: "kb-id", Slug: "entity/mencius",
		Title: "孟子", PageType: types.WikiPageTypeEntity, Status: types.WikiPageStatusPublished,
		Version: 1, CreatedAt: now, UpdatedAt: now,
	}))
	batched, err := svc.FindPagesByNormalizedTitles(ctx, "kb-id", types.WikiPageTypeEntity, []string{"孔子", "孟子", "孔子"})
	require.NoError(t, err)
	require.Len(t, batched, 2)
	slugs := []string{batched[0].Slug, batched[1].Slug}
	require.ElementsMatch(t, []string{"entity/confucius", "entity/mencius"}, slugs)
}