Create a struct with all of Hugo's config options

Primary motivation is documentation, but it will also hopefully simplify the code.

Also,

* Lower case the default output format names; this is in line with the custom ones (map keys) and how
it's treated all the places. This avoids doing `stringds.EqualFold` everywhere.

Closes #10896
Closes #10620

hugolib/page__meta.go

@@ -116,7 +116,7 @@ type pageMeta struct {
 	sections []string
 
 	// Sitemap overrides from front matter.
-	sitemap config.Sitemap
+	sitemap config.SitemapConfig
 
 	s *Site
 
@@ -139,24 +139,8 @@ func (p *pageMeta) Author() page.Author {
 }
 
 func (p *pageMeta) Authors() page.AuthorList {
-	helpers.Deprecated(".Authors", "Use taxonomies.", false)
-	authorKeys, ok := p.params["authors"]
-	if !ok {
-		return page.AuthorList{}
-	}
-	authors := authorKeys.([]string)
-	if len(authors) < 1 || len(p.s.Info.Authors) < 1 {
-		return page.AuthorList{}
-	}
-
-	al := make(page.AuthorList)
-	for _, author := range authors {
-		a, ok := p.s.Info.Authors[author]
-		if ok {
-			al[author] = a
-		}
-	}
-	return al
+	helpers.Deprecated(".Authors", "Use taxonomies.", true)
+	return nil
 }
 
 func (p *pageMeta) BundleType() files.ContentClass {
@@ -224,7 +208,7 @@ func (p *pageMeta) IsPage() bool {
 // This method is also implemented on SiteInfo.
 // TODO(bep) interface
 func (p *pageMeta) Param(key any) (any, error) {
-	return resource.Param(p, p.s.Info.Params(), key)
+	return resource.Param(p, p.s.Params(), key)
 }
 
 func (p *pageMeta) Params() maps.Params {
@@ -298,7 +282,7 @@ func (p *pageMeta) SectionsPath() string {
 	return path.Join(p.SectionsEntries()...)
 }
 
-func (p *pageMeta) Sitemap() config.Sitemap {
+func (p *pageMeta) Sitemap() config.SitemapConfig {
 	return p.sitemap
 }
 
@@ -502,17 +486,19 @@ func (pm *pageMeta) setMetadata(parentBucket *pagesMapBucket, p *pageState, fron
 			}
 		case "outputs":
 			o := cast.ToStringSlice(v)
+			// lower case names:
+			for i, s := range o {
+				o[i] = strings.ToLower(s)
+			}
 			if len(o) > 0 {
 				// Output formats are explicitly set in front matter, use those.
-				outFormats, err := p.s.outputFormatsConfig.GetByNames(o...)
-
+				outFormats, err := p.s.conf.OutputFormats.Config.GetByNames(o...)
 				if err != nil {
 					p.s.Log.Errorf("Failed to resolve output formats: %s", err)
 				} else {
 					pm.configuredOutputFormats = outFormats
 					pm.params[loki] = outFormats
 				}
-
 			}
 		case "draft":
 			draft = new(bool)
@@ -536,7 +522,10 @@ func (pm *pageMeta) setMetadata(parentBucket *pagesMapBucket, p *pageState, fron
 			}
 			pm.params[loki] = pm.aliases
 		case "sitemap":
-			p.m.sitemap = config.DecodeSitemap(p.s.siteCfg.sitemap, maps.ToStringMap(v))
+			p.m.sitemap, err = config.DecodeSitemap(p.s.conf.Sitemap, maps.ToStringMap(v))
+			if err != nil {
+				return fmt.Errorf("failed to decode sitemap config in front matter: %s", err)
+			}
 			pm.params[loki] = p.m.sitemap
 			sitemapSet = true
 		case "iscjklanguage":
@@ -575,7 +564,6 @@ func (pm *pageMeta) setMetadata(parentBucket *pagesMapBucket, p *pageState, fron
 				break
 			}
 			fallthrough
-
 		default:
 			// If not one of the explicit values, store in Params
 			switch vv := v.(type) {
@@ -601,6 +589,7 @@ func (pm *pageMeta) setMetadata(parentBucket *pagesMapBucket, p *pageState, fron
 				} else {
 					pm.params[loki] = []string{}
 				}
+
 			default:
 				pm.params[loki] = vv
 			}
@@ -608,7 +597,7 @@ func (pm *pageMeta) setMetadata(parentBucket *pagesMapBucket, p *pageState, fron
 	}
 
 	if !sitemapSet {
-		pm.sitemap = p.s.siteCfg.sitemap
+		pm.sitemap = p.s.conf.Sitemap
 	}
 
 	pm.markup = p.s.ContentSpec.ResolveMarkup(pm.markup)
@@ -625,7 +614,7 @@ func (pm *pageMeta) setMetadata(parentBucket *pagesMapBucket, p *pageState, fron
 
 	if isCJKLanguage != nil {
 		pm.isCJKLanguage = *isCJKLanguage
-	} else if p.s.siteCfg.hasCJKLanguage && p.source.parsed != nil {
+	} else if p.s.conf.HasCJKLanguage && p.source.parsed != nil {
 		if cjkRe.Match(p.source.parsed.Input()) {
 			pm.isCJKLanguage = true
 		} else {
@@ -692,7 +681,7 @@ func (p *pageMeta) applyDefaultValues(n *contentNode) error {
 	if p.title == "" && p.f.IsZero() {
 		switch p.Kind() {
 		case page.KindHome:
-			p.title = p.s.Info.title
+			p.title = p.s.Title()
 		case page.KindSection:
 			var sectionName string
 			if n != nil {
@@ -702,7 +691,7 @@ func (p *pageMeta) applyDefaultValues(n *contentNode) error {
 			}
 
 			sectionName = helpers.FirstUpper(sectionName)
-			if p.s.Cfg.GetBool("pluralizeListTitles") {
+			if p.s.conf.PluralizeListTitles {
 				p.title = flect.Pluralize(sectionName)
 			} else {
 				p.title = sectionName
@@ -710,9 +699,9 @@ func (p *pageMeta) applyDefaultValues(n *contentNode) error {
 		case page.KindTerm:
 			// TODO(bep) improve
 			key := p.sections[len(p.sections)-1]
-			p.title = strings.Replace(p.s.titleFunc(key), "-", " ", -1)
+			p.title = strings.Replace(p.s.conf.C.CreateTitle(key), "-", " ", -1)
 		case page.KindTaxonomy:
-			p.title = p.s.titleFunc(p.sections[0])
+			p.title = p.s.conf.C.CreateTitle(p.sections[0])
 		case kind404:
 			p.title = "404 Page not found"
 
@@ -775,8 +764,7 @@ func (m *pageMeta) outputFormats() output.Formats {
 	if len(m.configuredOutputFormats) > 0 {
 		return m.configuredOutputFormats
 	}
-
-	return m.s.outputFormats[m.Kind()]
+	return m.s.conf.C.KindOutputFormats[m.Kind()]
 }
 
 func (p *pageMeta) Slug() string {