hswg: merge in hasp as a mode

No need to have the two-line header processor in two places.

3 files changed, 61 insertions, 114 deletions

diff --git a/README.adoc b/README.adoc
index 62a7aac..0c0fa23 100644
--- a/README.adoc
+++ b/README.adoc
@@ -189,10 +189,11 @@ An improved replacement for autocutsel in selection synchronization "mode":
 
 Only UTF8_STRING-convertible selections are synchronized.
 
-hasp -- (lib)asciidoc syntax preprocessor
-~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
-Provisional tool to make libasciidoc understand more syntax, namely
-two-line/underlined titles for my Gitea projects.
+hswg -- static website generator
+~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
+Wraps libasciidoc to make it understand more syntax, namely two-line/underlined
+titles, and can be run either as an AsciiDoc processor for my Gitea, or as
+a trivial wiki-like site generator.
 
 ht -- terminal emulator
 ~~~~~~~~~~~~~~~~~~~~~~~
diff --git a/hasp/main.go b/hasp/main.go
deleted file mode 100644
index dd2ba7a..0000000
--- a/hasp/main.go
+++ /dev/null
@@ -1,91 +0,0 @@
-// Program hasp is a preprocessor for libasciidoc to make it understand
-// two-line/underlined titles, intended to be used in Gitea.
-package main
-
-import (
-	"bytes"
-	"encoding/xml"
-	"io"
-	"io/ioutil"
-	"os"
-	"strings"
-	"unicode"
-	"unicode/utf8"
-
-	"github.com/bytesparadise/libasciidoc"
-	"github.com/bytesparadise/libasciidoc/pkg/configuration"
-)
-
-// isTitle returns the title level if the lines seem to form a title,
-// zero otherwise. Input lines may inclide trailing newlines.
-func isTitle(line1, line2 []byte) int {
-	// This is a very naïve method, we should target graphemes (thus at least
-	// NFC normalize the lines first) and account for wide characters.
-	diff := utf8.RuneCount(line1) - utf8.RuneCount(line2)
-	if len(line2) < 2 || diff < -1 || diff > 1 {
-		return 0
-	}
-
-	// "Don't be fooled by back-to-back delimited blocks."
-	// Still gets fooled by other things, though.
-	if bytes.IndexFunc(line1, func(r rune) bool {
-		return unicode.IsLetter(r) || unicode.IsNumber(r)
-	}) < 0 {
-		return 0
-	}
-
-	// The underline must be homogenous.
-	for _, r := range bytes.TrimRight(line2, "\r\n") {
-		if r != line2[0] {
-			return 0
-		}
-	}
-	return 1 + strings.IndexByte("=-~^+", line2[0])
-}
-
-func writeLine(w *io.PipeWriter, cur, next []byte) []byte {
-	if level := isTitle(cur, next); level > 0 {
-		w.Write(append(bytes.Repeat([]byte{'='}, level), ' '))
-		next = nil
-	}
-	w.Write(cur)
-	return next
-}
-
-// ConvertTitles converts AsciiDoc two-line (underlined) titles to single-line.
-func ConvertTitles(w *io.PipeWriter, input []byte) {
-	var last []byte
-	for _, cur := range bytes.SplitAfter(input, []byte{'\n'}) {
-		last = writeLine(w, last, cur)
-	}
-	writeLine(w, last, nil)
-}
-
-func main() {
-	input, err := ioutil.ReadAll(os.Stdin)
-	if err != nil {
-		panic(err)
-	}
-
-	pr, pw := io.Pipe()
-	go func() {
-		defer pw.Close()
-		ConvertTitles(pw, input)
-	}()
-
-	// io.Copy(os.Stdout, pr)
-	// return
-
-	config := configuration.NewConfiguration(
-		configuration.WithHeaderFooter(true))
-	_, err = libasciidoc.ConvertToHTML(pr, os.Stdout, config)
-	if err != nil {
-		// Fallback: output all the text sanitized for direct inclusion.
-		os.Stdout.WriteString("<pre>")
-		for _, line := range bytes.Split(input, []byte{'\n'}) {
-			xml.EscapeText(os.Stdout, line)
-			os.Stdout.WriteString("\n")
-		}
-		os.Stdout.WriteString("</pre>")
-	}
-}
diff --git a/hswg/main.go b/hswg/main.go
index 595bb4a..2a46c6e 100644
--- a/hswg/main.go
+++ b/hswg/main.go
@@ -4,6 +4,7 @@ package main
 
 import (
 	"bytes"
+	"encoding/xml"
 	"fmt"
 	"io"
 	"io/ioutil"
@@ -67,6 +68,41 @@ func ConvertTitles(w *io.PipeWriter, input []byte) {
 	writeLine(w, last, nil)
 }
 
+// Render converts an io.Reader with an AsciiDoc document to HTML. So long as
+// the file could be read at all, it will always return a non-empty document.
+func Render(doc io.Reader, config configuration.Configuration) (
+	html *bytes.Buffer, meta types.Metadata, err error) {
+	html = bytes.NewBuffer(nil)
+
+	var input []byte
+	if input, err = ioutil.ReadAll(doc); err != nil {
+		return
+	}
+
+	pr, pw := io.Pipe()
+	go func() {
+		defer pw.Close()
+		ConvertTitles(pw, input)
+	}()
+
+	// io.Copy(os.Stdout, pr)
+	// return
+
+	meta, err = libasciidoc.ConvertToHTML(pr, html, config)
+	if err != nil {
+		// Fallback: output all the text sanitized for direct inclusion.
+		html.Reset()
+
+		_, _ = html.WriteString("<pre>")
+		for _, line := range bytes.Split(input, []byte{'\n'}) {
+			_ = xml.EscapeText(html, line)
+			_, _ = html.WriteString("\n")
+		}
+		_, _ = html.WriteString("</pre>")
+	}
+	return
+}
+
 // entry contains all context information about a single page.
 type entry struct {
 	path      string         // path
@@ -106,7 +142,23 @@ func expand(m *map[string]*entry, name string, chunk []byte) []byte {
 	})
 }
 
+func singleFile() {
+	html, meta, err := Render(os.Stdin, configuration.NewConfiguration())
+	if err != nil {
+		log.Println(err)
+	} else if meta.Title != "" {
+		_, _ = os.Stdout.WriteString("<h1>")
+		_ = xml.EscapeText(os.Stdout, []byte(meta.Title))
+		_, _ = os.Stdout.WriteString("</h1>\n")
+	}
+	_, _ = io.Copy(os.Stdout, html)
+}
+
 func main() {
+	if len(os.Args) < 2 {
+		singleFile()
+		return
+	}
 	if len(os.Args) < 3 {
 		log.Fatalf("usage: %s TEMPLATE GLOB...\n", os.Args[0])
 	}
@@ -146,32 +198,17 @@ func main() {
 			e.mtime = i.ModTime()
 		}
 
-		input, err := ioutil.ReadAll(f)
-		if err != nil {
-			log.Fatalln(err)
-		}
-
-		pr, pw := io.Pipe()
-		go func() {
-			defer pw.Close()
-			ConvertTitles(pw, input)
-		}()
-
-		config := configuration.NewConfiguration(
-			configuration.WithHeaderFooter(false),
+		var html *bytes.Buffer
+		if html, e.metadata, err = Render(f, configuration.NewConfiguration(
 			configuration.WithFilename(e.path),
 			configuration.WithLastUpdated(e.mtime),
-		)
-
-		buf := bytes.NewBuffer(nil)
-		e.metadata, err = libasciidoc.ConvertToHTML(pr, buf, config)
-		if err != nil {
+		)); err != nil {
 			log.Fatalln(err)
 		}
 
 		// Expand LinkWords anywhere between <tags>.
 		// We want something like the inverse of Regexp.ReplaceAllStringFunc.
-		raw, last, expanded := buf.Bytes(), 0, bytes.NewBuffer(nil)
+		raw, last, expanded := html.Bytes(), 0, bytes.NewBuffer(nil)
 		for _, where := range tagRE.FindAllIndex(raw, -1) {
 			_, _ = expanded.Write(expand(&entries, name, raw[last:where[0]]))
 			_, _ = expanded.Write(raw[where[0]:where[1]])