diff --git a/classes/schema/graph.go b/classes/schema/graph.go
index 221abcc..e39a1bc 100644
--- a/classes/schema/graph.go
+++ b/classes/schema/graph.go
@@ -53,13 +53,6 @@ const (
 	PublisherPerson       = "person"
 )
 
-// LocalTypes are the LocalBusiness types the settings offer (UI-SPEC C20).
-var LocalTypes = []string{
-	"LocalBusiness", "ProfessionalService", "Store", "FoodEstablishment",
-	"HealthAndBeautyBusiness", "MedicalBusiness", "LegalService",
-	"HomeAndConstructionBusiness", "AutomotiveBusiness", "FinancialService",
-}
-
 // Crumb is one breadcrumb: its name, absolute URL and site path.
 type Crumb struct {
 	Name string `json:"name"`
diff --git a/classes/schema/validate.go b/classes/schema/validate.go
new file mode 100644
index 0000000..fa866b2
--- /dev/null
+++ b/classes/schema/validate.go
@@ -0,0 +1,153 @@
+package schema
+
+import "strings"
+
+// The levels of a finding.
+const (
+	LevelRequired    = "required"
+	LevelRecommended = "recommended"
+)
+
+// Finding is one missing property of a node.
+type Finding struct {
+	Level    string `json:"level"`
+	Property string `json:"property"`
+}
+
+// Report is a node with its findings. Rules is false for a type Google has
+// no rich-result rules for (FAQPage, CollectionPage, WebPage, Service …;
+// RESEARCH Pitfall 11): it is checked as valid schema.org only.
+type Report struct {
+	ID       string    `json:"id"`
+	Type     string    `json:"type"`
+	Findings []Finding `json:"findings"`
+	Rules    bool      `json:"rules"`
+}
+
+// rule is the required and recommended properties of a type (Google's
+// structured data documentation, cited in 33-RESEARCH.md).
+type rule struct {
+	required    []string
+	recommended []string
+}
+
+var articleRule = rule{recommended: []string{"author", "datePublished", "dateModified", "headline", "image"}}
+
+var localRule = rule{required: []string{"name", "address"}, recommended: []string{"telephone", "url", "geo", "openingHoursSpecification", "priceRange", "image"}}
+
+// rules lists the types with Google rules; every other type has none.
+var rules = map[string]rule{
+	TypeArticle:        articleRule,
+	TypeBlogPosting:    articleRule,
+	TypeNewsArticle:    articleRule,
+	TypeBreadcrumbList: {required: []string{"itemListElement"}},
+	TypeVideoObject:    {required: []string{"name", "thumbnailUrl", "uploadDate"}, recommended: []string{"description", "embedUrl"}},
+	TypeOrganization:   {recommended: []string{"name", "url", "logo"}},
+	TypePerson:         {required: []string{"name"}, recommended: []string{"url", "image"}},
+	TypeWebSite:        {required: []string{"name", "url"}},
+	TypeProfilePage:    {required: []string{"mainEntity"}},
+}
+
+// localTypes are the LocalBusiness types (UI-SPEC C20), checked with the
+// LocalBusiness rules.
+var localTypes = map[string]bool{
+	"LocalBusiness": true, "ProfessionalService": true, "Store": true,
+	"FoodEstablishment": true, "HealthAndBeautyBusiness": true,
+	"MedicalBusiness": true, "LegalService": true,
+	"HomeAndConstructionBusiness": true, "AutomotiveBusiness": true,
+	"FinancialService": true,
+}
+
+// RulesFor returns the rule of typ and whether Google has rules for it.
+func RulesFor(typ string) (required, recommended []string, ok bool) {
+	if localTypes[typ] {
+		return localRule.required, localRule.recommended, true
+	}
+	r, ok := rules[typ]
+	return r.required, r.recommended, ok
+}
+
+// NodeType is a node's first @type, "" when it has none.
+func NodeType(n map[string]any) string {
+	switch t := n["@type"].(type) {
+	case string:
+		return t
+	case []any:
+		for _, v := range t {
+			if s, ok := v.(string); ok {
+				return s
+			}
+		}
+	case []string:
+		if len(t) > 0 {
+			return t[0]
+		}
+	}
+	return ""
+}
+
+// present reports whether a node property carries a value.
+func present(v any) bool {
+	switch x := v.(type) {
+	case nil:
+		return false
+	case string:
+		return strings.TrimSpace(x) != ""
+	case []any:
+		return len(x) > 0
+	case map[string]any:
+		return len(x) > 0
+	}
+	return true
+}
+
+// ValidateNode checks one node against its type's rules.
+func ValidateNode(n map[string]any) Report {
+	typ := NodeType(n)
+	id, _ := n["@id"].(string)
+	rep := Report{ID: id, Type: typ, Findings: []Finding{}}
+	required, recommended, ok := RulesFor(typ)
+	rep.Rules = ok
+	for _, p := range required {
+		if !present(n[p]) {
+			rep.Findings = append(rep.Findings, Finding{Level: LevelRequired, Property: p})
+		}
+	}
+	if typ == TypeBreadcrumbList {
+		if items, _ := n["itemListElement"].([]any); len(items) > 0 && len(items) < 2 {
+			rep.Findings = append(rep.Findings, Finding{Level: LevelRequired, Property: "itemListElement"})
+		}
+	}
+	for _, p := range recommended {
+		if !present(n[p]) {
+			rep.Findings = append(rep.Findings, Finding{Level: LevelRecommended, Property: p})
+		}
+	}
+	return rep
+}
+
+// Nodes returns the node objects of a graph.
+func Nodes(graph map[string]any) []map[string]any {
+	var out []map[string]any
+	switch list := graph["@graph"].(type) {
+	case []any:
+		for _, raw := range list {
+			if n, ok := raw.(map[string]any); ok {
+				out = append(out, n)
+			}
+		}
+	case []map[string]any:
+		out = append(out, list...)
+	}
+	return out
+}
+
+// Validate checks every node of a graph (D-46): the admin preview, the
+// MCP tool and the publisher preview share it.
+func Validate(graph map[string]any) []Report {
+	out := []Report{}
+	for _, n := range Nodes(graph) {
+		out = append(out, ValidateNode(n))
+	}
+	return out
+}
diff --git a/classes/settings_write.go b/classes/settings_write.go
index c56761e..5a530d2 100644
--- a/classes/settings_write.go
+++ b/classes/settings_write.go
@@ -39,7 +39,51 @@ var SettingsColumns = []string{
 	"noindex_paths", "search_paths", "url_host", "url_slash",
 	"url_lowercase", "links_new_tab", "nofollow_domains",
 	"sponsored_domains", "verify_google", "verify_bing", "verify_yandex",
-	"verify_other", "verify_files", "csv_delimiter",
+	"verify_other", "verify_files", "csv_delimiter", "breadcrumb_home",
+	"publisher_type", "publisher_name", "publisher_logo", "publisher_url",
+	"publisher_email", "publisher_phone", "publisher_same_as",
+	"local_enabled", "local_type", "local_price_range", "local_street",
+	"local_postal_code", "local_city", "local_region", "local_country",
+	"local_latitude", "local_longitude", "local_hours",
+}
+
+// settingsText maps the plain text settings columns to their fields.
+func settingsText(st *models.Settings) map[string]*string {
+	return map[string]*string{
+		"site_name":           &st.SiteName,
+		"twitter_site":        &st.TwitterSite,
+		"title_template":      &st.TitleTemplate,
+		"home_template":       &st.HomeTemplate,
+		"default_description": &st.DefaultDescription,
+		"default_og_image":    &st.DefaultOGImage,
+		"noindex_paths":       &st.NoindexPaths,
+		"search_paths":        &st.SearchPaths,
+		"url_host":            &st.URLHost,
+		"url_slash":           &st.URLSlash,
+		"verify_google":       &st.VerifyGoogle,
+		"verify_bing":         &st.VerifyBing,
+		"verify_yandex":       &st.VerifyYandex,
+		"csv_delimiter":       &st.CSVDelimiter,
+		"nofollow_domains":    &st.NofollowDomains,
+		"sponsored_domains":   &st.SponsoredDomains,
+		"breadcrumb_home":     &st.BreadcrumbHome,
+		"publisher_type":      &st.PublisherType,
+		"publisher_name":      &st.PublisherName,
+		"publisher_logo":      &st.PublisherLogo,
+		"publisher_url":       &st.PublisherURL,
+		"publisher_email":     &st.PublisherEmail,
+		"publisher_phone":     &st.PublisherPhone,
+		"publisher_same_as":   &st.PublisherSameAs,
+		"local_type":          &st.LocalType,
+		"local_price_range":   &st.LocalPriceRange,
+		"local_street":        &st.LocalStreet,
+		"local_postal_code":   &st.LocalPostalCode,
+		"local_city":          &st.LocalCity,
+		"local_region":        &st.LocalRegion,
+		"local_country":       &st.LocalCountry,
+		"local_latitude":      &st.LocalLatitude,
+		"local_longitude":     &st.LocalLongitude,
+	}
 }
 
 // SettingsValues are the settings row's values keyed by column, for
@@ -67,6 +111,25 @@ func SettingsValues(st models.Settings) map[string]any {
 		"verify_other":        plainValue(st.OtherMeta()),
 		"verify_files":        plainValue(st.Files()),
 		"csv_delimiter":       st.CSVDelimiter,
+		"breadcrumb_home":     st.BreadcrumbHome,
+		"publisher_type":      st.PublisherType,
+		"publisher_name":      st.PublisherName,
+		"publisher_logo":      st.PublisherLogo,
+		"publisher_url":       st.PublisherURL,
+		"publisher_email":     st.PublisherEmail,
+		"publisher_phone":     st.PublisherPhone,
+		"publisher_same_as":   st.PublisherSameAs,
+		"local_enabled":       st.LocalEnabled,
+		"local_type":          st.LocalType,
+		"local_price_range":   st.LocalPriceRange,
+		"local_street":        st.LocalStreet,
+		"local_postal_code":   st.LocalPostalCode,
+		"local_city":          st.LocalCity,
+		"local_region":        st.LocalRegion,
+		"local_country":       st.LocalCountry,
+		"local_latitude":      st.LocalLatitude,
+		"local_longitude":     st.LocalLongitude,
+		"local_hours":         plainValue(st.Hours()),
 	}
 }
 
@@ -93,52 +156,34 @@ func SetSettingsValue(st *models.Settings, column string, v any) error {
 		}
 		return json.Unmarshal(raw, dst)
 	}
+	if field, ok := settingsText(st)[column]; ok {
+		var err error
+		*field, err = text()
+		return err
+	}
 	var err error
 	switch column {
-	case "site_name":
-		st.SiteName, err = text()
-	case "twitter_site":
-		st.TwitterSite, err = text()
-	case "title_template":
-		st.TitleTemplate, err = text()
-	case "home_template":
-		st.HomeTemplate, err = text()
-	case "default_description":
-		st.DefaultDescription, err = text()
-	case "default_og_image":
-		st.DefaultOGImage, err = text()
-	case "noindex_paths":
-		st.NoindexPaths, err = text()
-	case "search_paths":
-		st.SearchPaths, err = text()
-	case "url_host":
-		st.URLHost, err = text()
-	case "url_slash":
-		st.URLSlash, err = text()
-	case "verify_google":
-		st.VerifyGoogle, err = text()
-	case "verify_bing":
-		st.VerifyBing, err = text()
-	case "verify_yandex":
-		st.VerifyYandex, err = text()
-	case "csv_delimiter":
-		st.CSVDelimiter, err = text()
-	case "nofollow_domains":
-		st.NofollowDomains, err = text()
-	case "sponsored_domains":
-		st.SponsoredDomains, err = text()
 	case "url_lowercase":
 		b, ok := v.(bool)
 		if !ok {
 			return fmt.Errorf("golem15.seo: settings %s is not a bool", column)
 		}
 		st.URLLowercase = b
-	case "links_new_tab":
+	case "links_new_tab", "local_enabled":
 		b, ok := v.(bool)
 		if !ok {
 			return fmt.Errorf("golem15.seo: settings %s is not a bool", column)
 		}
-		st.LinksNewTab = b
+		if column == "links_new_tab" {
+			st.LinksNewTab = b
+		} else {
+			st.LocalEnabled = b
+		}
+	case "local_hours":
+		var out []models.OpeningHours
+		if err = list(&out); err == nil {
+			st.LocalHours = lagoon.Jsonable[[]models.OpeningHours]{Data: out, Valid: true}
+		}
 	case "query_params":
 		var out []models.QueryParam
 		if err = list(&out); err == nil {
@@ -216,8 +261,14 @@ func (s *Service) SaveSettings(ctx context.Context, tx *gorm.DB, in SettingsWrit
 	oneOf("url_host", row.URLHost, models.HostKeep, models.HostWWW, models.HostBare)
 	oneOf("url_slash", row.URLSlash, models.SlashKeep, models.SlashAdd, models.SlashDrop)
 	oneOf("csv_delimiter", row.CSVDelimiter, "", ",", ";")
-	if _, sent := in.Values["default_og_image"]; sent && !ValidImageURL(row.DefaultOGImage) {
-		problems["default_og_image"] = append(problems["default_og_image"], models.Problem{Key: errImageURL})
+	for _, column := range []string{"default_og_image", "publisher_logo"} {
+		value := row.DefaultOGImage
+		if column == "publisher_logo" {
+			value = row.PublisherLogo
+		}
+		if _, sent := in.Values[column]; sent && !ValidImageURL(value) {
+			problems[column] = append(problems[column], models.Problem{Key: errImageURL})
+		}
 	}
 	for field, list := range row.Problems() {
 		problems[field] = append(problems[field], list...)
diff --git a/classes/structured.go b/classes/structured.go
index 168c0ff..96603d0 100644
--- a/classes/structured.go
+++ b/classes/structured.go
@@ -2,6 +2,7 @@ package classes
 
 import (
 	"context"
+	"encoding/json"
 	"strconv"
 	"strings"
 
@@ -220,3 +221,50 @@ func (s *Service) structuredData(ctx context.Context, db *gorm.DB, settings mode
 	res.JSONLD = graph
 	return nil
 }
+
+// PublisherPreview is the view model of the settings' P8 partial: the
+// generated publisher node as indented JSON and its findings as lines, or
+// the all-good line.
+type PublisherPreview struct {
+	JSON     string
+	Findings []string
+	AllGood  string
+}
+
+// FindingText renders a finding with the graph copy of the request locale.
+func (s *Service) FindingText(ctx context.Context, typ string, f schema.Finding) string {
+	key := "golem15.seo::lang.graph.recommended"
+	if f.Level == schema.LevelRequired {
+		key = "golem15.seo::lang.graph.required"
+	}
+	return s.PhraseCtx(ctx, key, map[string]string{"property": f.Property, "type": typ})
+}
+
+// PublisherPreview builds P8 from the stored settings in the default
+// locale (UI-SPEC C20).
+func (s *Service) PublisherPreview(ctx context.Context) (PublisherPreview, error) {
+	db, err := s.DB(ctx)
+	if err != nil {
+		return PublisherPreview{}, err
+	}
+	settings, err := LoadSettings(db)
+	if err != nil {
+		return PublisherPreview{}, err
+	}
+	locale := s.DefaultLocale(ctx, db)
+	node := schema.PublisherNode(s.SiteURL(), s.PublisherOf(ctx, db, settings, locale), s.SiteName(ctx, settings, locale))
+	out := PublisherPreview{AllGood: s.PhraseCtx(ctx, "golem15.seo::lang.graph.all_good", nil)}
+	if node == nil {
+		return out, nil
+	}
+	raw, err := json.MarshalIndent(node, "", "  ")
+	if err != nil {
+		return PublisherPreview{}, err
+	}
+	out.JSON = string(raw)
+	rep := schema.ValidateNode(node)
+	for _, f := range rep.Findings {
+		out.Findings = append(out.Findings, s.FindingText(ctx, rep.Type, f))
+	}
+	return out, nil
+}
diff --git a/controllers/api/settings.go b/controllers/api/settings.go
index 35cf545..b88cb3e 100644
--- a/controllers/api/settings.go
+++ b/controllers/api/settings.go
@@ -34,6 +34,25 @@ type UpdateSettingsInput struct {
 	VerifyOther        *[]models.VerifyMeta                `json:"verify_other,omitempty" jsonschema:"other verification meta tags (name, content)"`
 	VerifyFiles        *[]models.VerifyFile                `json:"verify_files,omitempty" jsonschema:"verification files served from the site root (filename, body)"`
 	CSVDelimiter       *string                             `json:"csv_delimiter,omitempty" jsonschema:"the import and export delimiter: , or ;"`
+	BreadcrumbHome     *string                             `json:"breadcrumb_home,omitempty" jsonschema:"the home page name in breadcrumb trails and BreadcrumbList (default locale); empty: Home / Strona główna"`
+	PublisherType      *string                             `json:"publisher_type,omitempty" jsonschema:"who publishes the site in the JSON-LD of every page: organization or person"`
+	PublisherName      *string                             `json:"publisher_name,omitempty" jsonschema:"the publisher name (default locale); empty: the site name"`
+	PublisherLogo      *string                             `json:"publisher_logo,omitempty" jsonschema:"the organisation logo (at least 112x112 px) or the person's photo: a URL or a site path"`
+	PublisherURL       *string                             `json:"publisher_url,omitempty" jsonschema:"the publisher website, an https URL; empty: the site address"`
+	PublisherEmail     *string                             `json:"publisher_email,omitempty" jsonschema:"the publisher contact email"`
+	PublisherPhone     *string                             `json:"publisher_phone,omitempty" jsonschema:"the publisher phone with the country code, e.g. +48 600 000 000"`
+	PublisherSameAs    *string                             `json:"publisher_same_as,omitempty" jsonschema:"profiles elsewhere (sameAs), one https URL per line"`
+	LocalEnabled       *bool                               `json:"local_enabled,omitempty" jsonschema:"publish the organisation as a local business (not for a person)"`
+	LocalType          *string                             `json:"local_type,omitempty" jsonschema:"the local business type: LocalBusiness, ProfessionalService, Store, FoodEstablishment, HealthAndBeautyBusiness, MedicalBusiness, LegalService, HomeAndConstructionBusiness, AutomotiveBusiness or FinancialService"`
+	LocalPriceRange    *string                             `json:"local_price_range,omitempty" jsonschema:"the price range, e.g. 50–200 zł or $$"`
+	LocalStreet        *string                             `json:"local_street,omitempty" jsonschema:"street and number (required for a local business)"`
+	LocalPostalCode    *string                             `json:"local_postal_code,omitempty" jsonschema:"postal code (required for a local business)"`
+	LocalCity          *string                             `json:"local_city,omitempty" jsonschema:"city (required for a local business)"`
+	LocalRegion        *string                             `json:"local_region,omitempty" jsonschema:"region"`
+	LocalCountry       *string                             `json:"local_country,omitempty" jsonschema:"two-letter country code, e.g. PL"`
+	LocalLatitude      *string                             `json:"local_latitude,omitempty" jsonschema:"latitude in decimal degrees (-90 to 90)"`
+	LocalLongitude     *string                             `json:"local_longitude,omitempty" jsonschema:"longitude in decimal degrees (-180 to 180)"`
+	LocalHours         *[]models.OpeningHours              `json:"local_hours,omitempty" jsonschema:"opening hours rows: day (mon … sun), opens and closes in 24-hour HH:MM; two rows split a day, a day without rows is closed"`
 	Types              map[string]classes.TypeSettingWrite `json:"types,omitempty" jsonschema:"per content type key: inject (show the SEO tab), title_template, description_template, robots"`
 }
 
diff --git a/controllers/settings.go b/controllers/settings.go
index 018ac31..b875426 100644
--- a/controllers/settings.go
+++ b/controllers/settings.go
@@ -107,8 +107,8 @@ type stagingView struct {
 }
 
 // PartialData serves the staging callout, shown outside production where
-// every page is noindex whatever the settings say (D-22), and the P3
-// placeholder table.
+// every page is noindex whatever the settings say (D-22), the P3
+// placeholder table and the P8 publisher preview.
 func (c settingsAdminController) PartialData(ctx context.Context, name string, _ any) (any, error) {
 	switch name {
 	case "staging":
@@ -119,6 +119,12 @@ func (c settingsAdminController) PartialData(ctx context.Context, name string, _
 			return nil, err
 		}
 		return svc.Placeholders(ctx), nil
+	case "publisher_preview":
+		svc, err := classes.NewService(appOf(c.app))
+		if err != nil {
+			return nil, err
+		}
+		return svc.PublisherPreview(ctx)
 	}
 	return nil, nil
 }
diff --git a/controllers/settings/_publisher_preview.htm b/controllers/settings/_publisher_preview.htm
new file mode 100644
index 0000000..0c74225
--- /dev/null
+++ b/controllers/settings/_publisher_preview.htm
@@ -0,0 +1,14 @@
+{{- if .Data.JSON -}}
+<div class="summer-markdown">
+<pre>{{ .Data.JSON }}</pre>
+</div>
+{{- end -}}
+{{- range .Data.Findings -}}
+<div class="summer-callout summer-callout--warning" role="status">
+<p class="summer-callout__text">{{ . }}</p>
+</div>
+{{- else -}}
+<div class="summer-callout" role="status">
+<p class="summer-callout__text">{{ .Data.AllGood }}</p>
+</div>
+{{- end -}}
diff --git a/lang/en/lang.yaml b/lang/en/lang.yaml
index 7ae9e79..ad6bbdb 100644
--- a/lang/en/lang.yaml
+++ b/lang/en/lang.yaml
@@ -149,6 +149,73 @@ settings:
     verify_filename_taken: Another verification file already uses this name.
     template_unknown: Unknown placeholder “:placeholder”. Use one from the table below the templates.
     breadcrumb_home_default: "Home"
+    tab_publisher: "Publisher"
+    tab_local: "Local business"
+    breadcrumb_home: "Home page name in breadcrumbs"
+    breadcrumb_home_comment: "The first item of every breadcrumb trail, also in the BreadcrumbList structured data."
+    publisher_type: "Publisher type"
+    publisher_org: "Organisation"
+    publisher_person: "Person (personal site)"
+    publisher_type_comment: "Who publishes the site, in the structured data of every page."
+    publisher_name: "Name"
+    publisher_name_comment: "Empty: the site name."
+    publisher_logo: "Logo or photo"
+    publisher_logo_comment: "Organisation: the logo, at least 112 × 112 px. Person: a photo."
+    publisher_url: "Website"
+    publisher_url_comment: "Empty: the site address."
+    publisher_same_as: "Profiles elsewhere (sameAs)"
+    publisher_same_as_comment: "One address per line: social profiles, Wikipedia, the company register entry."
+    same_as_invalid: "Line :line: use a full address starting with https://."
+    url_invalid: "Use a full address starting with https://."
+    email_invalid: "Enter an email address such as office@example.com."
+    publisher_email: "Contact email"
+    publisher_phone: "Phone"
+    publisher_phone_comment: "With the country code, e.g. +48 600 000 000."
+    publisher_preview: "Generated publisher data"
+    local_enabled: "Publish as a local business"
+    local_enabled_comment: "For a business with an address that customers visit, or with a service area. Not available for a person."
+    local_type: "Kind of business"
+    local_type_local_business: "Local business (general)"
+    local_type_professional_service: "Professional services"
+    local_type_store: "Shop"
+    local_type_food_establishment: "Restaurant or café"
+    local_type_health_and_beauty_business: "Health and beauty"
+    local_type_medical_business: "Medical practice"
+    local_type_legal_service: "Legal services"
+    local_type_home_and_construction_business: "Home and construction"
+    local_type_automotive_business: "Automotive"
+    local_type_financial_service: "Financial services"
+    local_price_range: "Price range"
+    local_price_range_comment: "e.g. 50–200 zł or $$."
+    local_street: "Street and number"
+    local_postal_code: "Postal code"
+    local_city: "City"
+    local_region: "Region"
+    local_country: "Country code"
+    local_country_comment: "Two letters, e.g. PL."
+    local_latitude: "Latitude"
+    local_longitude: "Longitude"
+    local_coordinates_comment: "Decimal degrees, e.g. 52.2297."
+    local_hours: "Opening hours"
+    local_hours_add: "Add opening hours"
+    local_hours_comment: "Add two rows for one day to split it, e.g. 9:00–13:00 and 14:00–18:00. A day without rows is closed."
+    hours_day: "Day"
+    hours_opens: "Opens"
+    hours_closes: "Closes"
+    day_mon: "Monday"
+    day_tue: "Tuesday"
+    day_wed: "Wednesday"
+    day_thu: "Thursday"
+    day_fri: "Friday"
+    day_sat: "Saturday"
+    day_sun: "Sunday"
+    hours_time_comment: "24-hour time, e.g. 09:00."
+    local_person: "A person cannot be a local business. Change the publisher type to Organisation, or turn this off."
+    local_address_required: "A local business needs a street, a postal code and a city."
+    time_invalid: "Use 24-hour time, e.g. 09:00."
+    hours_order: "Closing must come after opening."
+    country_invalid: "Use a two-letter country code, e.g. PL."
+    coordinate_invalid: "Enter decimal degrees: latitude from -90 to 90, longitude from -180 to 180."
 rules:
     new: New URL rule
     list_title: URL rules
@@ -410,3 +477,9 @@ pages:
         one: "Delete :count page from the registry? Its SEO tab is deleted with it."
         other: "Delete :count pages from the registry? Their SEO tabs are deleted with them."
     home_title: Home
+graph:
+    action: "Check structured data"
+    required: "Missing required property “:property” (:type)"
+    recommended: "Missing recommended property “:property” (:type)"
+    no_rules: ":type has no rich-result rules at Google; it is checked as valid schema.org only."
+    all_good: "No problems: every node has its required and recommended properties."
diff --git a/lang/pl/lang.yaml b/lang/pl/lang.yaml
index 797a136..e2223e4 100644
--- a/lang/pl/lang.yaml
+++ b/lang/pl/lang.yaml
@@ -151,6 +151,73 @@ settings:
     verify_filename_taken: Ten plik weryfikacyjny już istnieje.
     template_unknown: Nieznany znacznik „:placeholder”. Użyj jednego z tabeli pod szablonami.
     breadcrumb_home_default: "Strona główna"
+    tab_publisher: "Wydawca"
+    tab_local: "Firma lokalna"
+    breadcrumb_home: "Nazwa strony głównej w ścieżce nawigacji"
+    breadcrumb_home_comment: "Pierwszy element każdej ścieżki nawigacji, także w danych strukturalnych BreadcrumbList."
+    publisher_type: "Typ wydawcy"
+    publisher_org: "Organizacja"
+    publisher_person: "Osoba (strona prywatna)"
+    publisher_type_comment: "Kto wydaje witrynę, w danych strukturalnych każdej strony."
+    publisher_name: "Nazwa"
+    publisher_name_comment: "Puste: nazwa witryny."
+    publisher_logo: "Logo lub zdjęcie"
+    publisher_logo_comment: "Organizacja: logo, co najmniej 112 × 112 px. Osoba: zdjęcie."
+    publisher_url: "Strona internetowa"
+    publisher_url_comment: "Puste: adres witryny."
+    publisher_same_as: "Profile w innych serwisach (sameAs)"
+    publisher_same_as_comment: "Jeden adres w wierszu: profile społecznościowe, Wikipedia, wpis w KRS lub CEIDG."
+    same_as_invalid: "Wiersz :line: wpisz pełny adres zaczynający się od https://."
+    url_invalid: "Wpisz pełny adres zaczynający się od https://."
+    email_invalid: "Wpisz adres e-mail, np. biuro@example.com."
+    publisher_email: "E-mail kontaktowy"
+    publisher_phone: "Telefon"
+    publisher_phone_comment: "Z numerem kierunkowym kraju, np. +48 600 000 000."
+    publisher_preview: "Wygenerowane dane wydawcy"
+    local_enabled: "Publikuj jako firmę lokalną"
+    local_enabled_comment: "Dla firmy z adresem, który odwiedzają klienci, lub z obszarem obsługi. Niedostępne dla osoby."
+    local_type: "Rodzaj działalności"
+    local_type_local_business: "Firma lokalna (ogólnie)"
+    local_type_professional_service: "Usługi profesjonalne"
+    local_type_store: "Sklep"
+    local_type_food_establishment: "Restauracja lub kawiarnia"
+    local_type_health_and_beauty_business: "Zdrowie i uroda"
+    local_type_medical_business: "Praktyka medyczna"
+    local_type_legal_service: "Usługi prawne"
+    local_type_home_and_construction_business: "Dom i budownictwo"
+    local_type_automotive_business: "Motoryzacja"
+    local_type_financial_service: "Usługi finansowe"
+    local_price_range: "Przedział cen"
+    local_price_range_comment: "np. 50–200 zł lub $$."
+    local_street: "Ulica i numer"
+    local_postal_code: "Kod pocztowy"
+    local_city: "Miejscowość"
+    local_region: "Województwo lub region"
+    local_country: "Kod kraju"
+    local_country_comment: "Dwie litery, np. PL."
+    local_latitude: "Szerokość geograficzna"
+    local_longitude: "Długość geograficzna"
+    local_coordinates_comment: "Stopnie dziesiętne, np. 52.2297."
+    local_hours: "Godziny otwarcia"
+    local_hours_add: "Dodaj godziny otwarcia"
+    local_hours_comment: "Dodaj dwa wiersze dla jednego dnia, aby go podzielić, np. 9:00–13:00 i 14:00–18:00. Dzień bez wierszy jest nieczynny."
+    hours_day: "Dzień"
+    hours_opens: "Otwarcie"
+    hours_closes: "Zamknięcie"
+    day_mon: "Poniedziałek"
+    day_tue: "Wtorek"
+    day_wed: "Środa"
+    day_thu: "Czwartek"
+    day_fri: "Piątek"
+    day_sat: "Sobota"
+    day_sun: "Niedziela"
+    hours_time_comment: "Format 24-godzinny, np. 09:00."
+    local_person: "Osoba nie może być firmą lokalną. Zmień typ wydawcy na Organizacja lub wyłącz tę opcję."
+    local_address_required: "Firma lokalna wymaga ulicy, kodu pocztowego i miejscowości."
+    time_invalid: "Użyj formatu 24-godzinnego, np. 09:00."
+    hours_order: "Godzina zamknięcia musi być późniejsza niż otwarcia."
+    country_invalid: "Użyj dwuliterowego kodu kraju, np. PL."
+    coordinate_invalid: "Wpisz stopnie dziesiętne: szerokość od -90 do 90, długość od -180 do 180."
 rules:
     new: Nowa reguła adresu
     list_title: Reguły adresów
@@ -424,3 +491,9 @@ pages:
         many: "Usunąć :count stron z rejestru? Ich zakładki SEO zostaną usunięte."
         other: "Usunąć :count strony z rejestru? Ich zakładki SEO zostaną usunięte."
     home_title: Strona główna
+graph:
+    action: "Sprawdź dane strukturalne"
+    required: "Brak wymaganej właściwości „:property” (:type)"
+    recommended: "Brak zalecanej właściwości „:property” (:type)"
+    no_rules: ":type nie ma reguł wyników z elementami rozszerzonymi w Google; sprawdzana jest tylko poprawność schema.org."
+    all_good: "Brak problemów: każdy węzeł ma wymagane i zalecane właściwości."
diff --git a/models/settings.go b/models/settings.go
index feebbc8..d358edf 100644
--- a/models/settings.go
+++ b/models/settings.go
@@ -2,6 +2,7 @@ package models
 
 import (
 	"fmt"
+	"net/url"
 	"regexp"
 	"strconv"
 	"strings"
@@ -40,8 +41,28 @@ const (
 	errVerifyFilenameTaken   = "golem15.seo::lang.settings.verify_filename_taken"
 	errTemplateUnknown       = "golem15.seo::lang.settings.template_unknown"
 	errDomainInvalid         = "golem15.seo::lang.settings.domain_invalid"
+	errValueInvalid          = "golem15.seo::lang.api.value_invalid"
+	errSameAsInvalid         = "golem15.seo::lang.settings.same_as_invalid"
+	errURLInvalid            = "golem15.seo::lang.settings.url_invalid"
+	errEmailInvalid          = "golem15.seo::lang.settings.email_invalid"
+	errLocalPerson           = "golem15.seo::lang.settings.local_person"
+	errLocalAddress          = "golem15.seo::lang.settings.local_address_required"
+	errTimeInvalid           = "golem15.seo::lang.settings.time_invalid"
+	errHoursOrder            = "golem15.seo::lang.settings.hours_order"
+	errCountryInvalid        = "golem15.seo::lang.settings.country_invalid"
+	errCoordinateInvalid     = "golem15.seo::lang.settings.coordinate_invalid"
 )
 
+// LocalTypes are the LocalBusiness types the settings offer (UI-SPEC C20).
+var LocalTypes = []string{
+	"LocalBusiness", "ProfessionalService", "Store", "FoodEstablishment",
+	"HealthAndBeautyBusiness", "MedicalBusiness", "LegalService",
+	"HomeAndConstructionBusiness", "AutomotiveBusiness", "FinancialService",
+}
+
+// Days are the day codes of the opening hours, Monday first.
+var Days = []string{"mon", "tue", "wed", "thu", "fri", "sat", "sun"}
+
 // QueryParam is one row of the D-07 query-parameter list: a name (a
 // trailing * matches a prefix), its kind, and an optional path pattern the
 // row is limited to.
@@ -174,7 +195,12 @@ func (Settings) Fillable() []string {
 		"noindex_paths", "search_paths", "url_host", "url_slash",
 		"url_lowercase", "verify_google", "verify_bing", "verify_yandex",
 		"verify_other", "verify_files", "links_new_tab", "nofollow_domains",
-		"sponsored_domains",
+		"sponsored_domains", "breadcrumb_home", "publisher_type",
+		"publisher_name", "publisher_logo", "publisher_url", "publisher_email",
+		"publisher_phone", "publisher_same_as", "local_enabled", "local_type",
+		"local_price_range", "local_street", "local_postal_code", "local_city",
+		"local_region", "local_country", "local_latitude", "local_longitude",
+		"local_hours",
 	}
 }
 
@@ -278,6 +304,108 @@ func (s Settings) Problems() map[string][]Problem {
 			out[field] = p
 		}
 	}
+	for field, list := range s.PublisherProblems() {
+		out[field] = append(out[field], list...)
+	}
+	return out
+}
+
+// timePattern is a 24-hour HH:MM time.
+var timePattern = regexp.MustCompile(`^([01][0-9]|2[0-3]):[0-5][0-9]$`)
+
+// countryPattern is a two-letter country code.
+var countryPattern = regexp.MustCompile(`^[A-Za-z]{2}$`)
+
+// HTTPSURL reports whether s is an absolute https URL with a host.
+func HTTPSURL(s string) bool {
+	u, err := url.Parse(strings.TrimSpace(s))
+	return err == nil && u.Scheme == "https" && u.Host != "" && !strings.ContainsAny(s, " \t\n<>\"")
+}
+
+// oneOfList reports whether v is one of list.
+func oneOfList(v string, list []string) bool {
+	for _, item := range list {
+		if v == item {
+			return true
+		}
+	}
+	return false
+}
+
+// PublisherProblems lists the refusals of the Publisher and Local
+// business tabs (UI-SPEC C20, D-45, T-33-25): the publisher type, https
+// sameAs lines (with the line number), the website, the email, a person
+// as a local business, the business's address, country, coordinates and
+// opening hours (local_hours.<i>.opens / .closes).
+func (s Settings) PublisherProblems() map[string][]Problem {
+	out := map[string][]Problem{}
+	add := func(field string, p Problem) { out[field] = append(out[field], p) }
+	if s.PublisherType != "" && !oneOfList(s.PublisherType, []string{PublisherOrganization, PublisherPerson}) {
+		add("publisher_type", Problem{Key: errValueInvalid})
+	}
+	n := 0
+	for _, line := range strings.Split(strings.ReplaceAll(s.PublisherSameAs, "\r\n", "\n"), "\n") {
+		n++
+		if v := strings.TrimSpace(line); v != "" && !HTTPSURL(v) {
+			add("publisher_same_as", Problem{Key: errSameAsInvalid, Params: map[string]string{"line": strconv.Itoa(n)}})
+			break
+		}
+	}
+	if v := strings.TrimSpace(s.PublisherURL); v != "" && !HTTPSURL(v) {
+		add("publisher_url", Problem{Key: errURLInvalid})
+	}
+	if v := strings.TrimSpace(s.PublisherEmail); v != "" {
+		local, domain, ok := strings.Cut(v, "@")
+		if !ok || local == "" || !strings.Contains(domain, ".") || strings.ContainsAny(v, " <>\"") {
+			add("publisher_email", Problem{Key: errEmailInvalid})
+		}
+	}
+	if !s.LocalEnabled {
+		return out
+	}
+	if s.PublisherType == PublisherPerson {
+		add("local_enabled", Problem{Key: errLocalPerson})
+	}
+	if s.LocalType != "" && !oneOfList(s.LocalType, LocalTypes) {
+		add("local_type", Problem{Key: errValueInvalid})
+	}
+	if strings.TrimSpace(s.LocalStreet) == "" || strings.TrimSpace(s.LocalPostalCode) == "" || strings.TrimSpace(s.LocalCity) == "" {
+		for field, v := range map[string]string{"local_street": s.LocalStreet, "local_postal_code": s.LocalPostalCode, "local_city": s.LocalCity} {
+			if strings.TrimSpace(v) == "" {
+				add(field, Problem{Key: errLocalAddress})
+			}
+		}
+	}
+	if v := strings.TrimSpace(s.LocalCountry); v != "" && !countryPattern.MatchString(v) {
+		add("local_country", Problem{Key: errCountryInvalid})
+	}
+	coordinate := func(field, v string, limit float64) {
+		if v = strings.TrimSpace(v); v == "" {
+			return
+		}
+		f, err := strconv.ParseFloat(strings.ReplaceAll(v, ",", "."), 64)
+		if err != nil || f < -limit || f > limit {
+			add(field, Problem{Key: errCoordinateInvalid})
+		}
+	}
+	coordinate("local_latitude", s.LocalLatitude, 90)
+	coordinate("local_longitude", s.LocalLongitude, 180)
+	for i, h := range s.Hours() {
+		base := fmt.Sprintf("local_hours.%d.", i)
+		if !oneOfList(h.Day, Days) {
+			add(base+"day", Problem{Key: errValueInvalid})
+		}
+		okOpens, okCloses := timePattern.MatchString(h.Opens), timePattern.MatchString(h.Closes)
+		if !okOpens {
+			add(base+"opens", Problem{Key: errTimeInvalid})
+		}
+		if !okCloses {
+			add(base+"closes", Problem{Key: errTimeInvalid})
+		}
+		if okOpens && okCloses && h.Closes <= h.Opens {
+			add(base+"closes", Problem{Key: errHoursOrder})
+		}
+	}
 	return out
 }
 
diff --git a/models/settings/fields.yaml b/models/settings/fields.yaml
index 356d430..80e708a 100644
--- a/models/settings/fields.yaml
+++ b/models/settings/fields.yaml
@@ -2,9 +2,9 @@
 #  Form Field Definitions
 # ===================================
 #
-# SEO settings (UI-SPEC C11): General, one tab per content type (added by
-# the plugin's form extension after General), Indexing, Addresses, Links
-# (UI-SPEC C20) and Verification.
+# SEO settings (UI-SPEC C11, C20): General, one tab per content type (added
+# by the plugin's form extension after General), Indexing, Addresses,
+# Links, Publisher, Local business and Verification.
 
 fields:
     _staging:
@@ -27,6 +27,13 @@ fields:
         span: right
         tab: golem15.seo::lang.settings.tab_general
 
+    breadcrumb_home:
+        label: golem15.seo::lang.settings.breadcrumb_home
+        comment: golem15.seo::lang.settings.breadcrumb_home_comment
+        type: mltext
+        span: right
+        tab: golem15.seo::lang.settings.tab_general
+
     title_template:
         label: golem15.seo::lang.settings.title_template
         comment: golem15.seo::lang.settings.title_template_comment
@@ -163,6 +170,215 @@ fields:
         span: right
         tab: golem15.seo::lang.settings.tab_links
 
+    publisher_type:
+        label: golem15.seo::lang.settings.publisher_type
+        comment: golem15.seo::lang.settings.publisher_type_comment
+        type: dropdown
+        span: left
+        default: organization
+        options:
+            organization: golem15.seo::lang.settings.publisher_org
+            person: golem15.seo::lang.settings.publisher_person
+        tab: golem15.seo::lang.settings.tab_publisher
+
+    publisher_name:
+        label: golem15.seo::lang.settings.publisher_name
+        comment: golem15.seo::lang.settings.publisher_name_comment
+        type: mltext
+        span: right
+        tab: golem15.seo::lang.settings.tab_publisher
+
+    publisher_logo:
+        label: golem15.seo::lang.settings.publisher_logo
+        comment: golem15.seo::lang.settings.publisher_logo_comment
+        type: seoimage
+        span: full
+        tab: golem15.seo::lang.settings.tab_publisher
+
+    publisher_url:
+        label: golem15.seo::lang.settings.publisher_url
+        comment: golem15.seo::lang.settings.publisher_url_comment
+        type: text
+        span: left
+        tab: golem15.seo::lang.settings.tab_publisher
+
+    publisher_email:
+        label: golem15.seo::lang.settings.publisher_email
+        type: text
+        span: right
+        tab: golem15.seo::lang.settings.tab_publisher
+
+    publisher_phone:
+        label: golem15.seo::lang.settings.publisher_phone
+        comment: golem15.seo::lang.settings.publisher_phone_comment
+        type: text
+        span: left
+        tab: golem15.seo::lang.settings.tab_publisher
+
+    publisher_same_as:
+        label: golem15.seo::lang.settings.publisher_same_as
+        comment: golem15.seo::lang.settings.publisher_same_as_comment
+        type: textarea
+        size: small
+        span: full
+        tab: golem15.seo::lang.settings.tab_publisher
+
+    _publisher_preview:
+        label: golem15.seo::lang.settings.publisher_preview
+        type: partial
+        path: publisher_preview
+        span: full
+        context: update
+        tab: golem15.seo::lang.settings.tab_publisher
+
+    local_enabled:
+        label: golem15.seo::lang.settings.local_enabled
+        comment: golem15.seo::lang.settings.local_enabled_comment
+        type: switch
+        span: full
+        default: false
+        tab: golem15.seo::lang.settings.tab_local
+
+    local_type:
+        label: golem15.seo::lang.settings.local_type
+        type: dropdown
+        span: left
+        default: LocalBusiness
+        options:
+            LocalBusiness: golem15.seo::lang.settings.local_type_local_business
+            ProfessionalService: golem15.seo::lang.settings.local_type_professional_service
+            Store: golem15.seo::lang.settings.local_type_store
+            FoodEstablishment: golem15.seo::lang.settings.local_type_food_establishment
+            HealthAndBeautyBusiness: golem15.seo::lang.settings.local_type_health_and_beauty_business
+            MedicalBusiness: golem15.seo::lang.settings.local_type_medical_business
+            LegalService: golem15.seo::lang.settings.local_type_legal_service
+            HomeAndConstructionBusiness: golem15.seo::lang.settings.local_type_home_and_construction_business
+            AutomotiveBusiness: golem15.seo::lang.settings.local_type_automotive_business
+            FinancialService: golem15.seo::lang.settings.local_type_financial_service
+        tab: golem15.seo::lang.settings.tab_local
+        trigger:
+            action: hide
+            field: local_enabled
+            condition: unchecked
+
+    local_price_range:
+        label: golem15.seo::lang.settings.local_price_range
+        comment: golem15.seo::lang.settings.local_price_range_comment
+        type: text
+        span: right
+        tab: golem15.seo::lang.settings.tab_local
+        trigger:
+            action: hide
+            field: local_enabled
+            condition: unchecked
+
+    local_street:
+        label: golem15.seo::lang.settings.local_street
+        type: text
+        span: full
+        tab: golem15.seo::lang.settings.tab_local
+        trigger:
+            action: hide
+            field: local_enabled
+            condition: unchecked
+
+    local_postal_code:
+        label: golem15.seo::lang.settings.local_postal_code
+        type: text
+        span: left
+        tab: golem15.seo::lang.settings.tab_local
+        trigger:
+            action: hide
+            field: local_enabled
+            condition: unchecked
+
+    local_city:
+        label: golem15.seo::lang.settings.local_city
+        type: text
+        span: right
+        tab: golem15.seo::lang.settings.tab_local
+        trigger:
+            action: hide
+            field: local_enabled
+            condition: unchecked
+
+    local_region:
+        label: golem15.seo::lang.settings.local_region
+        type: text
+        span: left
+        tab: golem15.seo::lang.settings.tab_local
+        trigger:
+            action: hide
+            field: local_enabled
+            condition: unchecked
+
+    local_country:
+        label: golem15.seo::lang.settings.local_country
+        comment: golem15.seo::lang.settings.local_country_comment
+        type: text
+        span: right
+        tab: golem15.seo::lang.settings.tab_local
+        trigger:
+            action: hide
+            field: local_enabled
+            condition: unchecked
+
+    local_latitude:
+        label: golem15.seo::lang.settings.local_latitude
+        comment: golem15.seo::lang.settings.local_coordinates_comment
+        type: text
+        span: left
+        tab: golem15.seo::lang.settings.tab_local
+        trigger:
+            action: hide
+            field: local_enabled
+            condition: unchecked
+
+    local_longitude:
+        label: golem15.seo::lang.settings.local_longitude
+        comment: golem15.seo::lang.settings.local_coordinates_comment
+        type: text
+        span: right
+        tab: golem15.seo::lang.settings.tab_local
+        trigger:
+            action: hide
+            field: local_enabled
+            condition: unchecked
+
+    local_hours:
+        label: golem15.seo::lang.settings.local_hours
+        comment: golem15.seo::lang.settings.local_hours_comment
+        type: repeater
+        prompt: golem15.seo::lang.settings.local_hours_add
+        titleFrom: day
+        span: full
+        tab: golem15.seo::lang.settings.tab_local
+        form:
+            fields:
+                day:
+                    label: golem15.seo::lang.settings.hours_day
+                    type: dropdown
+                    span: left
+                    default: mon
+                    options:
+                        mon: golem15.seo::lang.settings.day_mon
+                        tue: golem15.seo::lang.settings.day_tue
+                        wed: golem15.seo::lang.settings.day_wed
+                        thu: golem15.seo::lang.settings.day_thu
+                        fri: golem15.seo::lang.settings.day_fri
+                        sat: golem15.seo::lang.settings.day_sat
+                        sun: golem15.seo::lang.settings.day_sun
+                opens:
+                    label: golem15.seo::lang.settings.hours_opens
+                    comment: golem15.seo::lang.settings.hours_time_comment
+                    type: text
+                    span: left
+                closes:
+                    label: golem15.seo::lang.settings.hours_closes
+                    comment: golem15.seo::lang.settings.hours_time_comment
+                    type: text
+                    span: right
+
     verify_google:
         label: golem15.seo::lang.settings.verify_google
         comment: golem15.seo::lang.settings.verify_code_comment
diff --git a/settings_test.go b/settings_test.go
index 94a9761..417365b 100644
--- a/settings_test.go
+++ b/settings_test.go
@@ -31,7 +31,7 @@ func TestSettingsTypeTabs(t *testing.T) {
 		env := bootEnv(t)
 		token := env.admin(t, true)
 		fields := env.formSchema(t, token, "golem15/seo/settings")
-		if got, want := strings.Join(tabsOf(fields), " | "), "General | Page | Tags | Notes | Site page | Indexing | Addresses | Links | Verification"; got != want {
+		if got, want := strings.Join(tabsOf(fields), " | "), "General | Page | Tags | Notes | Site page | Indexing | Addresses | Links | Publisher | Local business | Verification"; got != want {
 			t.Fatalf("settings tabs = %q, want %q", got, want)
 		}
 		findField(t, fields, "type_acme_page_inject")
@@ -81,7 +81,7 @@ func TestSettingsTypeTabs(t *testing.T) {
 	t.Run("no other content types", func(t *testing.T) {
 		env := bootPlugins(t, []string{"golem15.seo"})
 		token := env.admin(t, true)
-		if got, want := strings.Join(tabsOf(env.formSchema(t, token, "golem15/seo/settings")), " | "), "General | Site page | Indexing | Addresses | Links | Verification"; got != want {
+		if got, want := strings.Join(tabsOf(env.formSchema(t, token, "golem15/seo/settings")), " | "), "General | Site page | Indexing | Addresses | Links | Publisher | Local business | Verification"; got != want {
 			t.Fatalf("settings tabs = %q, want %q", got, want)
 		}
 	})
diff --git a/structured_data_test.go b/structured_data_test.go
index 5e16357..26614ba 100644
--- a/structured_data_test.go
+++ b/structured_data_test.go
@@ -3,6 +3,8 @@ package seo_test
 import (
 	"context"
 	"encoding/json"
+	"net/http"
+	"net/http/httptest"
 	"strings"
 	"sync"
 	"testing"
@@ -365,3 +367,113 @@ func crumbNames(res map[string]any) string {
 	}
 	return strings.Join(names, " > ")
 }
+
+// refusal asserts a 422 save answer naming field with message.
+func refusal(t *testing.T, rec *httptest.ResponseRecorder, field, message string) {
+	t.Helper()
+	body := rec.Body.String()
+	if rec.Code != http.StatusUnprocessableEntity || !strings.Contains(body, `"`+field+`"`) || !strings.Contains(body, message) {
+		t.Fatalf("save = %d %s, want 422 on %s with %q", rec.Code, body, field, message)
+	}
+}
+
+// TestPublisherSettings covers the Publisher and Local business tabs
+// (UI-SPEC C20, D-45, D-03): the saved values, every C20 refusal (422) in
+// the admin and the API, the local business node and the P8 preview.
+func TestPublisherSettings(t *testing.T) {
+	env := bootBlog(t)
+	token := env.admin(t, true)
+	fields := env.formSchema(t, token, "golem15/seo/settings")
+	for _, name := range []string{"breadcrumb_home", "publisher_type", "publisher_name", "publisher_logo", "publisher_same_as", "local_enabled", "local_hours", "_publisher_preview"} {
+		findField(t, fields, name)
+	}
+	settings := adminAPI("/golem15/seo/settings/1")
+	env.expect(t, http.StatusOK, http.MethodPut, settings, token, map[string]any{
+		"publisher_type": "organization", "publisher_name": "Acme Sp. z o.o.", "publisher_url": "https://acme.example.test/",
+		"publisher_email": "office@acme.example.test", "publisher_phone": "+48 600 000 000",
+		"publisher_same_as": "https://www.facebook.com/acme\nhttps://pl.wikipedia.org/wiki/Acme",
+	})
+	show := env.expect(t, http.StatusOK, http.MethodGet, "/_seo/api/v1/settings", token, nil).Body.String()
+	for _, want := range []string{`"publisher_name":"Acme Sp. z o.o."`, `"publisher_phone":"+48 600 000 000"`, `"local_enabled":false`} {
+		if !jsonContains(show, want) {
+			t.Fatalf("settings lack %s: %s", want, show)
+		}
+	}
+
+	// P8 without a logo: the node and a recommended-logo warning.
+	preview := env.expect(t, http.StatusOK, http.MethodGet, adminAPI("/golem15/seo/settings/partials/publisher_preview?id=1"), token, nil).Body.String()
+	if !strings.Contains(preview, "Acme Sp. z o.o.") || !strings.Contains(preview, `Missing recommended property “logo” (Organization)`) {
+		t.Fatalf("P8 = %s", preview)
+	}
+	env.expect(t, http.StatusOK, http.MethodPut, settings, token, map[string]any{"publisher_logo": "/media/logo.png"})
+	preview = env.expect(t, http.StatusOK, http.MethodGet, adminAPI("/golem15/seo/settings/partials/publisher_preview?id=1"), token, nil).Body.String()
+	if !strings.Contains(preview, "No problems") || strings.Contains(preview, "Missing") {
+		t.Fatalf("P8 with a logo = %s", preview)
+	}
+
+	// The C20 refusals, in the admin form.
+	refusal(t, env.call(t, http.MethodPut, settings, token, map[string]any{"publisher_same_as": "https://ok.example.test\nx.pl"}), "publisher_same_as", "Line 2: use a full address starting with https://.")
+	refusal(t, env.call(t, http.MethodPut, settings, token, map[string]any{"publisher_same_as": "x.pl"}), "publisher_same_as", "Line 1: use a full address")
+	refusal(t, env.call(t, http.MethodPut, settings, token, map[string]any{"publisher_type": "person", "local_enabled": true, "local_street": "Prosta 1", "local_postal_code": "00-001", "local_city": "Warszawa"}), "local_enabled", "A person cannot be a local business.")
+	local := map[string]any{"publisher_type": "organization", "local_enabled": true, "local_street": "Prosta 1", "local_postal_code": "00-001", "local_city": "Warszawa"}
+	with := func(k string, v any) map[string]any {
+		out := map[string]any{}
+		for key, value := range local {
+			out[key] = value
+		}
+		out[k] = v
+		return out
+	}
+	refusal(t, env.call(t, http.MethodPut, settings, token, with("local_street", "")), "local_street", "A local business needs a street, a postal code and a city.")
+	refusal(t, env.call(t, http.MethodPut, settings, token, with("local_hours", []map[string]any{{"day": "mon", "opens": "9:00", "closes": "17:00"}})), "local_hours.0.opens", "Use 24-hour time, e.g. 09:00.")
+	refusal(t, env.call(t, http.MethodPut, settings, token, with("local_hours", []map[string]any{{"day": "mon", "opens": "17:00", "closes": "09:00"}})), "local_hours.0.closes", "Closing must come after opening.")
+	refusal(t, env.call(t, http.MethodPut, settings, token, with("local_country", "POL")), "local_country", "Use a two-letter country code, e.g. PL.")
+	refusal(t, env.call(t, http.MethodPut, settings, token, with("local_latitude", "91")), "local_latitude", "Enter decimal degrees")
+	// The same checks through the API (MCP seo_update_settings).
+	refusal(t, env.call(t, http.MethodPut, "/_seo/api/v1/settings", token, map[string]any{"local_enabled": true, "publisher_type": "person"}), "local_enabled", "A person cannot be a local business.")
+	refusal(t, env.call(t, http.MethodPut, "/_seo/api/v1/settings", token, map[string]any{"publisher_same_as": "x.pl"}), "publisher_same_as", "Line 1: use a full address")
+
+	// A valid local business: the publisher node becomes its type with
+	// the address, geo, opening hours and price range.
+	env.expect(t, http.StatusOK, http.MethodPut, "/_seo/api/v1/settings", token, map[string]any{
+		"local_enabled": true, "local_type": "FoodEstablishment", "local_street": "Prosta 1", "local_postal_code": "00-001",
+		"local_city": "Warszawa", "local_country": "pl", "local_latitude": "52.2297", "local_longitude": "21.0122",
+		"local_price_range": "$$", "local_hours": []map[string]any{{"day": "mon", "opens": "09:00", "closes": "13:00"}, {"day": "mon", "opens": "14:00", "closes": "18:00"}},
+	})
+	nodes := graphNodes(t, env.resolve(t, "/"))
+	biz := nodes["FoodEstablishment"]
+	if biz == nil || biz["@id"] != siteURL+"/#organization" || biz["priceRange"] != "$$" || biz["telephone"] != "+48 600 000 000" {
+		t.Fatalf("local business node = %v", nodes)
+	}
+	if got := asJSON(t, biz["address"]); got != `{"@type":"PostalAddress","addressCountry":"PL","addressLocality":"Warszawa","postalCode":"00-001","streetAddress":"Prosta 1"}` {
+		t.Fatalf("address = %s", got)
+	}
+	if got := asJSON(t, biz["geo"]); got != `{"@type":"GeoCoordinates","latitude":52.2297,"longitude":21.0122}` {
+		t.Fatalf("geo = %s", got)
+	}
+	if hours, _ := biz["openingHoursSpecification"].([]any); len(hours) != 2 || hours[1].(map[string]any)["opens"] != "14:00" || hours[0].(map[string]any)["dayOfWeek"] != "Monday" {
+		t.Fatalf("hours = %v", biz["openingHoursSpecification"])
+	}
+	if got := asJSON(t, biz["sameAs"]); got != `["https://www.facebook.com/acme","https://pl.wikipedia.org/wiki/Acme"]` {
+		t.Fatalf("sameAs = %s", got)
+	}
+	if biz["url"] != "https://acme.example.test/" || asJSON(t, biz["logo"]) != `{"@id":"https://www.example.test/#logo","@type":"ImageObject","contentUrl":"https://www.example.test/media/logo.png","url":"https://www.example.test/media/logo.png"}` {
+		t.Fatalf("url/logo = %v %v", biz["url"], biz["logo"])
+	}
+
+	// A person publisher: #person, no local business.
+	env.expect(t, http.StatusOK, http.MethodPut, "/_seo/api/v1/settings", token, map[string]any{"local_enabled": false, "publisher_type": "person", "publisher_name": "Jan Kowalski"})
+	nodes = graphNodes(t, env.resolve(t, "/"))
+	if p := nodes["Person"]; p == nil || p["@id"] != siteURL+"/#person" || p["name"] != "Jan Kowalski" || idOf(nodes["WebSite"]["publisher"]) != siteURL+"/#person" {
+		t.Fatalf("person publisher = %v", nodes)
+	}
+
+	// The home crumb name.
+	if got := crumbNames(env.resolve(t, "/blog/solo")); got != "Home > Solo" {
+		t.Fatalf("default home crumb trail = %s", got)
+	}
+	env.expect(t, http.StatusOK, http.MethodPut, settings, token, map[string]any{"breadcrumb_home": "Start"})
+	if got := crumbNames(env.resolve(t, "/blog/solo")); got != "Start > Solo" {
+		t.Fatalf("home crumb trail = %s", got)
+	}
+}