package docs

import (
	"os"
	"path/filepath"
	"testing"

	"bookhoard/templates"
)

func TestPlaceDoc(t *testing.T) {
	tests := []struct {
		path    string
		section string
		group   string
		pinned  bool
	}{
		{"index.md", "Getting Started", "", true},
		{"user/user-guide.md", "User Guide", "", true},
		{"user/dashboard.md", "User Guide", "", false},
		{"user/admin-guide.md", "User Guide", "Administration", false},
		{"user/devices/kobo-setup.md", "User Guide", "Devices", false},
		{"developer/api/api-reference.md", "API Reference", "", true},
		{"developer/api/dashboard.md", "API Reference", "", false},
		{"developer/api/authentication/login.md", "API Reference", "Authentication", false},
		{"developer/api/saved-filters/index.md", "API Reference", "Saved Filters", true},
		{"developer/testing.md", "Developer", "", false},
		{"developer/development.md", "Developer", "", true},
		{"developer/scanner/audio-metadata.md", "Developer", "Scanner", false},
		{"contract_pins.md", "Developer", "Reference", false},
		{"FRONTEND_INTEGRATION.md", "Developer", "Reference", false},
		{"development/calibre-opf-implementation.md", "Developer", "Reference", false},
		{"operations/operations.md", "Operations", "", true},
		{"operations/troubleshooting.md", "Operations", "", false},
		{"contributing/contributing.md", "Contributing", "", true},
		{"contributing/development.md", "Contributing", "", false},
	}

	for _, tt := range tests {
		got := placeDoc(tt.path)
		if got.section != tt.section || got.group != tt.group {
			t.Errorf("placeDoc(%q) = (%q, %q), want (%q, %q)",
				tt.path, got.section, got.group, tt.section, tt.group)
		}
		if (got.pin < 0) != tt.pinned {
			t.Errorf("placeDoc(%q) pin = %d, pinned want %v", tt.path, got.pin, tt.pinned)
		}
	}
}

func TestDocTitle(t *testing.T) {
	tests := map[string]string{
		"index.md":                                 "Overview",
		"user/user-guide.md":                       "User Guide",
		"user/devices/koreader-setup.md":           "KOReader Setup",
		"developer/development.md":                 "Developer Portal",
		"developer/api/api-reference.md":           "Overview",
		"developer/api/users/update_profile.md":    "Update Profile",
		"developer/api/book-matching/link_book.md": "Link Book",
		"operations/troubleshooting.md":            "Troubleshooting",
		"contract_pins.md":                         "Contract Pins",
	}
	for path, want := range tests {
		if got := docTitle(path); got != want {
			t.Errorf("docTitle(%q) = %q, want %q", path, got, want)
		}
	}
}

func TestDocURL(t *testing.T) {
	if got := docURL("index.md"); got != "/docs" {
		t.Errorf("docURL(index.md) = %q, want /docs", got)
	}
	if got := docURL("user/sync-guide.md"); got != "/docs/user/sync-guide" {
		t.Errorf("docURL = %q, want /docs/user/sync-guide", got)
	}
}

// buildTestDocs creates a representative docs tree in a temp dir and returns
// a handler over it.
func buildTestDocs(t *testing.T) *DocsHandler {
	t.Helper()
	dir := t.TempDir()
	files := []string{
		"index.md",
		"user/user-guide.md",
		"user/dashboard.md",
		"user/admin-guide.md",
		"user/devices/kobo-setup.md",
		"user/devices/koreader-setup.md",
		"developer/api/api-reference.md",
		"developer/api/authentication/login.md",
		"developer/api/authentication/overview.md",
		"developer/api/saved-filters/index.md",
		"developer/testing.md",
		"operations/troubleshooting.md",
		"contributing/development.md",
		"contract_pins.md",
	}
	for _, f := range files {
		path := filepath.Join(dir, f)
		if err := os.MkdirAll(filepath.Dir(path), 0o755); err != nil {
			t.Fatal(err)
		}
		if err := os.WriteFile(path, []byte("# Test\n"), 0o644); err != nil {
			t.Fatal(err)
		}
	}
	return &DocsHandler{docsFS: os.DirFS(dir), docsPath: dir}
}

func TestBuildNavigation(t *testing.T) {
	h := buildTestDocs(t)

	// Current page: a device setup guide → User Guide section and its
	// Devices group must render expanded; everything else collapsed.
	nav := h.BuildNavigation("/docs/user/devices/kobo-setup")
	if len(nav.Sections) == 0 {
		t.Fatal("no sections built")
	}

	wantOrder := []string{"Getting Started", "User Guide", "API Reference", "Developer", "Operations", "Contributing"}
	for i, want := range wantOrder {
		if nav.Sections[i].Title != want {
			t.Fatalf("section %d = %q, want %q", i, nav.Sections[i].Title, want)
		}
	}

	getting := nav.Sections[0]
	if getting.Collapsed {
		t.Error("Getting Started should be expanded (root overview pinned)")
	}
	if len(getting.Items) != 1 || getting.Items[0].Title != "Overview" || getting.Items[0].URL != "/docs" {
		t.Errorf("Getting Started items = %+v, want single Overview → /docs", getting.Items)
	}

	userGuide := nav.Sections[1]
	if userGuide.Collapsed {
		t.Error("User Guide should be expanded: it contains the current page")
	}
	if len(userGuide.Items) != 2 || userGuide.Items[0].Title != "User Guide" {
		t.Errorf("User Guide direct items = %+v, want User Guide pinned first", userGuide.Items)
	}
	var devices *templates.NavGroup
	for i := range userGuide.Groups {
		if userGuide.Groups[i].Title == "Devices" {
			devices = &userGuide.Groups[i]
		}
	}
	if devices == nil {
		t.Fatal("User Guide has no Devices group")
	}
	if devices.Collapsed {
		t.Error("Devices group should be expanded: it contains the current page")
	}
	if len(devices.Items) != 2 || devices.Items[0].Title != "Kobo Setup" {
		t.Errorf("Devices items = %+v, want Kobo Setup + KOReader Setup", devices.Items)
	}

	// Everything else starts collapsed.
	for _, s := range nav.Sections[2:] {
		if !s.Collapsed {
			t.Errorf("section %q should be collapsed (current page is elsewhere)", s.Title)
		}
	}

	// API Reference: subdirectory groups with the index page as Overview.
	api := nav.Sections[2]
	if len(api.Groups) != 2 {
		t.Fatalf("API Reference groups = %d, want 2 (Authentication, Saved Filters)", len(api.Groups))
	}
	if api.Groups[0].Title != "Authentication" || len(api.Groups[0].Items) != 2 {
		t.Errorf("Authentication group = %+v", api.Groups[0])
	}
	saved := api.Groups[1]
	if saved.Title != "Saved Filters" || len(saved.Items) != 1 || saved.Items[0].Title != "Overview" {
		t.Errorf("Saved Filters group = %+v, want single Overview item", saved)
	}
	if !saved.Collapsed {
		t.Error("Saved Filters group should be collapsed on an unrelated page")
	}

	// Stray root files land in Developer → Reference.
	dev := nav.Sections[3]
	if len(dev.Groups) != 1 || dev.Groups[0].Title != "Reference" {
		t.Errorf("Developer groups = %+v, want Reference", dev.Groups)
	}
}

func TestBuildNavigationNothingCurrent(t *testing.T) {
	h := buildTestDocs(t)
	nav := h.BuildNavigation("/docs/nonexistent")
	open := 0
	for _, s := range nav.Sections {
		if !s.Collapsed {
			open++
		}
	}
	if open != 1 {
		t.Errorf("expected exactly one section open on a 404 path, got %d", open)
	}
	if nav.Sections[0].Collapsed {
		t.Error("fallback should open the first section")
	}
}