Create pages from _content.gotmpl

Closes #12427
Closes #12485
Closes #6310
Closes #5074

media/config.go

@@ -14,13 +14,14 @@
 package media
 
 import (
-	"errors"
 	"fmt"
+	"path/filepath"
 	"reflect"
 	"sort"
 	"strings"
 
 	"github.com/gohugoio/hugo/common/maps"
+	"github.com/gohugoio/hugo/common/paths"
 	"github.com/gohugoio/hugo/config"
 
 	"github.com/mitchellh/mapstructure"
@@ -31,6 +32,11 @@ import (
 var DefaultTypes Types
 
 func init() {
+	// Apply delimiter to all.
+	for _, m := range defaultMediaTypesConfig {
+		m.(map[string]any)["delimiter"] = "."
+	}
+
 	ns, err := DecodeTypes(nil)
 	if err != nil {
 		panic(err)
@@ -39,17 +45,122 @@ func init() {
 
 	// Initialize the Builtin types with values from DefaultTypes.
 	v := reflect.ValueOf(&Builtin).Elem()
+
 	for i := 0; i < v.NumField(); i++ {
 		f := v.Field(i)
+		fieldName := v.Type().Field(i).Name
 		builtinType := f.Interface().(Type)
+		if builtinType.Type == "" {
+			panic(fmt.Errorf("builtin type %q is empty", fieldName))
+		}
 		defaultType, found := DefaultTypes.GetByType(builtinType.Type)
 		if !found {
-			panic(errors.New("missing default type for builtin type: " + builtinType.Type))
+			panic(fmt.Errorf("missing default type for field builtin type: %q", fieldName))
 		}
 		f.Set(reflect.ValueOf(defaultType))
 	}
 }
 
+func init() {
+	DefaultContentTypes = ContentTypes{
+		HTML:             Builtin.HTMLType,
+		Markdown:         Builtin.MarkdownType,
+		AsciiDoc:         Builtin.AsciiDocType,
+		Pandoc:           Builtin.PandocType,
+		ReStructuredText: Builtin.ReStructuredTextType,
+		EmacsOrgMode:     Builtin.EmacsOrgModeType,
+	}
+
+	DefaultContentTypes.init()
+}
+
+var DefaultContentTypes ContentTypes
+
+// ContentTypes holds the media types that are considered content in Hugo.
+type ContentTypes struct {
+	HTML             Type
+	Markdown         Type
+	AsciiDoc         Type
+	Pandoc           Type
+	ReStructuredText Type
+	EmacsOrgMode     Type
+
+	// Created in init().
+	types        Types
+	extensionSet map[string]bool
+}
+
+func (t *ContentTypes) init() {
+	t.types = Types{t.HTML, t.Markdown, t.AsciiDoc, t.Pandoc, t.ReStructuredText, t.EmacsOrgMode}
+	t.extensionSet = make(map[string]bool)
+	for _, mt := range t.types {
+		for _, suffix := range mt.Suffixes() {
+			t.extensionSet[suffix] = true
+		}
+	}
+}
+
+func (t ContentTypes) IsContentSuffix(suffix string) bool {
+	return t.extensionSet[suffix]
+}
+
+// IsContentFile returns whether the given filename is a content file.
+func (t ContentTypes) IsContentFile(filename string) bool {
+	return t.IsContentSuffix(strings.TrimPrefix(filepath.Ext(filename), "."))
+}
+
+// IsIndexContentFile returns whether the given filename is an index content file.
+func (t ContentTypes) IsIndexContentFile(filename string) bool {
+	if !t.IsContentFile(filename) {
+		return false
+	}
+
+	base := filepath.Base(filename)
+
+	return strings.HasPrefix(base, "index.") || strings.HasPrefix(base, "_index.")
+}
+
+// IsHTMLSuffix returns whether the given suffix is a HTML media type.
+func (t ContentTypes) IsHTMLSuffix(suffix string) bool {
+	for _, s := range t.HTML.Suffixes() {
+		if s == suffix {
+			return true
+		}
+	}
+	return false
+}
+
+// Types is a slice of media types.
+func (t ContentTypes) Types() Types {
+	return t.types
+}
+
+// FromTypes creates a new ContentTypes updated with the values from the given Types.
+func (t ContentTypes) FromTypes(types Types) ContentTypes {
+	if tt, ok := types.GetByType(t.HTML.Type); ok {
+		t.HTML = tt
+	}
+	if tt, ok := types.GetByType(t.Markdown.Type); ok {
+		t.Markdown = tt
+	}
+	if tt, ok := types.GetByType(t.AsciiDoc.Type); ok {
+		t.AsciiDoc = tt
+	}
+	if tt, ok := types.GetByType(t.Pandoc.Type); ok {
+		t.Pandoc = tt
+	}
+	if tt, ok := types.GetByType(t.ReStructuredText.Type); ok {
+		t.ReStructuredText = tt
+	}
+	if tt, ok := types.GetByType(t.EmacsOrgMode.Type); ok {
+		t.EmacsOrgMode = tt
+	}
+
+	t.init()
+
+	return t
+}
+
 // Hold the configuration for a given media type.
 type MediaTypeConfig struct {
 	// The file suffixes used for this media type.
@@ -105,3 +216,10 @@ func DecodeTypes(in map[string]any) (*config.ConfigNamespace[map[string]MediaTyp
 	}
 	return ns, nil
 }
+
+// TODO(bep) get rid of this.
+var DefaultPathParser = &paths.PathParser{
+	IsContentExt: func(ext string) bool {
+		return DefaultContentTypes.IsContentSuffix(ext)
+	},
+}