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

markup/asciidocext/convert.go

@@ -17,26 +17,11 @@
 package asciidocext
 
 import (
-	"bytes"
-	"path/filepath"
-	"strings"
-
-	"github.com/gohugoio/hugo/common/hexec"
 	"github.com/gohugoio/hugo/htesting"
-
-	"github.com/gohugoio/hugo/identity"
-	"github.com/gohugoio/hugo/markup/asciidocext/asciidocext_config"
+	"github.com/gohugoio/hugo/markup/asciidocext/internal"
 	"github.com/gohugoio/hugo/markup/converter"
-	"github.com/gohugoio/hugo/markup/internal"
-	"github.com/gohugoio/hugo/markup/tableofcontents"
-	"golang.org/x/net/html"
 )
 
-/* ToDo: RelPermalink patch for svg posts not working*/
-type pageSubset interface {
-	RelPermalink() string
-}
-
 // Provider is the package entry point.
 var Provider converter.ProviderProvider = provider{}
 
@@ -44,274 +29,16 @@ type provider struct{}
 
 func (p provider) New(cfg converter.ProviderConfig) (converter.Provider, error) {
 	return converter.NewProvider("asciidocext", func(ctx converter.DocumentContext) (converter.Converter, error) {
-		return &asciidocConverter{
-			ctx: ctx,
-			cfg: cfg,
+		return &internal.AsciidocConverter{
+			Ctx: ctx,
+			Cfg: cfg,
 		}, nil
 	}), nil
 }
 
-type asciidocResult struct {
-	converter.ResultRender
-	toc *tableofcontents.Fragments
-}
-
-func (r asciidocResult) TableOfContents() *tableofcontents.Fragments {
-	return r.toc
-}
-
-type asciidocConverter struct {
-	ctx converter.DocumentContext
-	cfg converter.ProviderConfig
-}
-
-func (a *asciidocConverter) Convert(ctx converter.RenderContext) (converter.ResultRender, error) {
-	b, err := a.getAsciidocContent(ctx.Src, a.ctx)
-	if err != nil {
-		return nil, err
-	}
-	content, toc, err := a.extractTOC(b)
-	if err != nil {
-		return nil, err
-	}
-	return asciidocResult{
-		ResultRender: converter.Bytes(content),
-		toc:          toc,
-	}, nil
-}
-
-func (a *asciidocConverter) Supports(_ identity.Identity) bool {
-	return false
-}
-
-// getAsciidocContent calls asciidoctor as an external helper
-// to convert AsciiDoc content to HTML.
-func (a *asciidocConverter) getAsciidocContent(src []byte, ctx converter.DocumentContext) ([]byte, error) {
-	if !hasAsciiDoc() {
-		a.cfg.Logger.Errorln("asciidoctor not found in $PATH: Please install.\n",
-			"                 Leaving AsciiDoc content unrendered.")
-		return src, nil
-	}
-
-	args := a.parseArgs(ctx)
-	args = append(args, "-")
-
-	a.cfg.Logger.Infoln("Rendering", ctx.DocumentName, " using asciidoctor args", args, "...")
-
-	return internal.ExternallyRenderContent(a.cfg, ctx, src, asciiDocBinaryName, args)
-}
-
-func (a *asciidocConverter) parseArgs(ctx converter.DocumentContext) []string {
-	cfg := a.cfg.MarkupConfig.AsciidocExt
-	args := []string{}
-
-	args = a.appendArg(args, "-b", cfg.Backend, asciidocext_config.CliDefault.Backend, asciidocext_config.AllowedBackend)
-
-	for _, extension := range cfg.Extensions {
-		if strings.LastIndexAny(extension, `\/.`) > -1 {
-			a.cfg.Logger.Errorln("Unsupported asciidoctor extension was passed in. Extension `" + extension + "` ignored. Only installed asciidoctor extensions are allowed.")
-			continue
-		}
-		args = append(args, "-r", extension)
-	}
-
-	for attributeKey, attributeValue := range cfg.Attributes {
-		if asciidocext_config.DisallowedAttributes[attributeKey] {
-			a.cfg.Logger.Errorln("Unsupported asciidoctor attribute was passed in. Attribute `" + attributeKey + "` ignored.")
-			continue
-		}
-
-		args = append(args, "-a", attributeKey+"="+attributeValue)
-	}
-
-	if cfg.WorkingFolderCurrent {
-		contentDir := filepath.Dir(ctx.Filename)
-		sourceDir := a.cfg.Cfg.GetString("source")
-		destinationDir := a.cfg.Cfg.GetString("destination")
-
-		if destinationDir == "" {
-			a.cfg.Logger.Errorln("markup.asciidocext.workingFolderCurrent requires hugo command option --destination to be set")
-		}
-		if !filepath.IsAbs(destinationDir) && sourceDir != "" {
-			destinationDir = filepath.Join(sourceDir, destinationDir)
-		}
-
-		var outDir string
-		var err error
-
-		file := filepath.Base(ctx.Filename)
-		if a.cfg.Cfg.GetBool("uglyUrls") || file == "_index.adoc" || file == "index.adoc" {
-			outDir, err = filepath.Abs(filepath.Dir(filepath.Join(destinationDir, ctx.DocumentName)))
-		} else {
-			postDir := ""
-			page, ok := ctx.Document.(pageSubset)
-			if ok {
-				postDir = filepath.Base(page.RelPermalink())
-			} else {
-				a.cfg.Logger.Errorln("unable to cast interface to pageSubset")
-			}
-
-			outDir, err = filepath.Abs(filepath.Join(destinationDir, filepath.Dir(ctx.DocumentName), postDir))
-		}
-
-		if err != nil {
-			a.cfg.Logger.Errorln("asciidoctor outDir: ", err)
-		}
-
-		args = append(args, "--base-dir", contentDir, "-a", "outdir="+outDir)
-	}
-
-	if cfg.NoHeaderOrFooter {
-		args = append(args, "--no-header-footer")
-	} else {
-		a.cfg.Logger.Warnln("asciidoctor parameter NoHeaderOrFooter is expected for correct html rendering")
-	}
-
-	if cfg.SectionNumbers {
-		args = append(args, "--section-numbers")
-	}
-
-	if cfg.Verbose {
-		args = append(args, "--verbose")
-	}
-
-	if cfg.Trace {
-		args = append(args, "--trace")
-	}
-
-	args = a.appendArg(args, "--failure-level", cfg.FailureLevel, asciidocext_config.CliDefault.FailureLevel, asciidocext_config.AllowedFailureLevel)
-
-	args = a.appendArg(args, "--safe-mode", cfg.SafeMode, asciidocext_config.CliDefault.SafeMode, asciidocext_config.AllowedSafeMode)
-
-	return args
-}
-
-func (a *asciidocConverter) appendArg(args []string, option, value, defaultValue string, allowedValues map[string]bool) []string {
-	if value != defaultValue {
-		if allowedValues[value] {
-			args = append(args, option, value)
-		} else {
-			a.cfg.Logger.Errorln("Unsupported asciidoctor value `" + value + "` for option " + option + " was passed in and will be ignored.")
-		}
-	}
-	return args
-}
-
-const asciiDocBinaryName = "asciidoctor"
-
-func hasAsciiDoc() bool {
-	return hexec.InPath(asciiDocBinaryName)
-}
-
-// extractTOC extracts the toc from the given src html.
-// It returns the html without the TOC, and the TOC data
-func (a *asciidocConverter) extractTOC(src []byte) ([]byte, *tableofcontents.Fragments, error) {
-	var buf bytes.Buffer
-	buf.Write(src)
-	node, err := html.Parse(&buf)
-	if err != nil {
-		return nil, nil, err
-	}
-	var (
-		f       func(*html.Node) bool
-		toc     *tableofcontents.Fragments
-		toVisit []*html.Node
-	)
-	f = func(n *html.Node) bool {
-		if n.Type == html.ElementNode && n.Data == "div" && attr(n, "id") == "toc" {
-			toc = parseTOC(n)
-			if !a.cfg.MarkupConfig.AsciidocExt.PreserveTOC {
-				n.Parent.RemoveChild(n)
-			}
-			return true
-		}
-		if n.FirstChild != nil {
-			toVisit = append(toVisit, n.FirstChild)
-		}
-		if n.NextSibling != nil && f(n.NextSibling) {
-			return true
-		}
-		for len(toVisit) > 0 {
-			nv := toVisit[0]
-			toVisit = toVisit[1:]
-			if f(nv) {
-				return true
-			}
-		}
-		return false
-	}
-	f(node)
-	if err != nil {
-		return nil, nil, err
-	}
-	buf.Reset()
-	err = html.Render(&buf, node)
-	if err != nil {
-		return nil, nil, err
-	}
-	// ltrim <html><head></head><body> and rtrim </body></html> which are added by html.Render
-	res := buf.Bytes()[25:]
-	res = res[:len(res)-14]
-	return res, toc, nil
-}
-
-// parseTOC returns a TOC root from the given toc Node
-func parseTOC(doc *html.Node) *tableofcontents.Fragments {
-	var (
-		toc tableofcontents.Builder
-		f   func(*html.Node, int, int)
-	)
-	f = func(n *html.Node, row, level int) {
-		if n.Type == html.ElementNode {
-			switch n.Data {
-			case "ul":
-				if level == 0 {
-					row++
-				}
-				level++
-				f(n.FirstChild, row, level)
-			case "li":
-				for c := n.FirstChild; c != nil; c = c.NextSibling {
-					if c.Type != html.ElementNode || c.Data != "a" {
-						continue
-					}
-					href := attr(c, "href")[1:]
-					toc.AddAt(&tableofcontents.Heading{
-						Title: nodeContent(c),
-						ID:    href,
-					}, row, level)
-				}
-				f(n.FirstChild, row, level)
-			}
-		}
-		if n.NextSibling != nil {
-			f(n.NextSibling, row, level)
-		}
-	}
-	f(doc.FirstChild, -1, 0)
-	return toc.Build()
-}
-
-func attr(node *html.Node, key string) string {
-	for _, a := range node.Attr {
-		if a.Key == key {
-			return a.Val
-		}
-	}
-	return ""
-}
-
-func nodeContent(node *html.Node) string {
-	var buf bytes.Buffer
-	for c := node.FirstChild; c != nil; c = c.NextSibling {
-		html.Render(&buf, c)
-	}
-	return buf.String()
-}
-
 // Supports returns whether Asciidoctor is installed on this computer.
 func Supports() bool {
-	hasBin := hasAsciiDoc()
+	hasBin := internal.HasAsciiDoc()
 	if htesting.SupportsAll() {
 		if !hasBin {
 			panic("asciidoctor not installed")