mugit @ b7356aab67e27e0bcf94ab1bdfa9c336aacc39d7

M internal/mdx/relative_link.go

@@ -1,15 +1,18 @@
 package mdx
 
 import (
+	"bytes"
 	"fmt"
 	"net/url"
 	"path"
 	"path/filepath"
+	"regexp"
 	"strings"
 
 	"github.com/yuin/goldmark"
 	"github.com/yuin/goldmark/ast"
 	"github.com/yuin/goldmark/parser"
+	"github.com/yuin/goldmark/renderer"
 	"github.com/yuin/goldmark/text"
 	"github.com/yuin/goldmark/util"
 )
@@ -32,70 +35,118 @@ type relativeLink struct{}
 
 func (e *relativeLink) Extend(m goldmark.Markdown) {
 	m.Parser().AddOptions(
-		parser.WithASTTransformers(
-			util.Prioritized(&relinkTransformer{}, 100),
-		),
+		parser.WithASTTransformers(util.Prioritized(&relinkTransformer{}, 100)),
+	)
+	m.Renderer().AddOptions(
+		renderer.WithNodeRenderers(util.Prioritized(&rawBlockRenderer{}, 100)),
 	)
 }
 
+type rawBlock struct {
+	ast.BaseBlock
+	data []byte
+}
+
+var rawBlockKind = ast.NewNodeKind("RawBlock")
+
+func (r *rawBlock) Kind() ast.NodeKind   { return rawBlockKind }
+func (r *rawBlock) Dump(_ []byte, _ int) {}
+
+type rawBlockRenderer struct{}
+
+func (r *rawBlockRenderer) RegisterFuncs(reg renderer.NodeRendererFuncRegisterer) {
+	reg.Register(rawBlockKind, func(w util.BufWriter, _ []byte, node ast.Node, entering bool) (ast.WalkStatus, error) {
+		if entering {
+			w.Write(node.(*rawBlock).data)
+		}
+		return ast.WalkContinue, nil
+	})
+}
+
 type relinkTransformer struct{}
 
 func (t *relinkTransformer) Transform(node *ast.Document, reader text.Reader, pc parser.Context) {
 	repoName, _ := pc.Get(repoNameKey).(string)
 	baseDir, _ := pc.Get(baseDirKey).(string)
 
-	if repoName == "" {
-		return
-	}
-
 	_ = ast.Walk(node, func(n ast.Node, entering bool) (ast.WalkStatus, error) {
 		if !entering {
 			return ast.WalkContinue, nil
 		}
 
-		var dest *[]byte
 		switch v := n.(type) {
 		case *ast.Image:
-			dest = &v.Destination
+			if rewritten := t.rewriteDest(v.Destination, repoName, baseDir); rewritten != nil {
+				v.Destination = rewritten
+			}
 		case *ast.Link:
-			dest = &v.Destination
-		default:
-			return ast.WalkContinue, nil
+			if rewritten := t.rewriteDest(v.Destination, repoName, baseDir); rewritten != nil {
+				v.Destination = rewritten
+			}
+		case *ast.RawHTML:
+			var buf []byte
+			for i := 0; i < v.Segments.Len(); i++ {
+				buf = append(buf, reader.Value(v.Segments.At(i))...)
+			}
+			updated := t.rewriteSrc(buf, repoName, baseDir)
+			if !bytes.Equal(updated, buf) {
+				str := ast.NewString(updated)
+				str.SetRaw(true)
+				n.Parent().ReplaceChild(n.Parent(), n, str)
+			}
+		case *ast.HTMLBlock:
+			var buf []byte
+			for i := 0; i < v.Lines().Len(); i++ {
+				buf = append(buf, reader.Value(v.Lines().At(i))...)
+			}
+			updated := t.rewriteSrc(buf, repoName, baseDir)
+			if !bytes.Equal(updated, buf) {
+				n.Parent().ReplaceChild(n.Parent(), n, &rawBlock{data: updated})
+			}
 		}
 
-		urlStr := string(*dest)
-
-		// skip absolute URLs
-		if strings.HasPrefix(urlStr, "http://") ||
-			strings.HasPrefix(urlStr, "https://") ||
-			strings.HasPrefix(urlStr, "//") ||
-			strings.HasPrefix(urlStr, "#") ||
-			strings.HasPrefix(urlStr, "mailto:") ||
-			strings.HasPrefix(urlStr, "data:") {
-			return ast.WalkContinue, nil
-		}
+		return ast.WalkContinue, nil
+	})
+}
 
-		urlStr = strings.TrimPrefix(urlStr, "./")
+func (t *relinkTransformer) rewriteDest(dest []byte, repoName, baseDir string) []byte {
+	urlStr := string(dest)
+	if strings.HasPrefix(urlStr, "http://") ||
+		strings.HasPrefix(urlStr, "https://") ||
+		strings.HasPrefix(urlStr, "//") ||
+		strings.HasPrefix(urlStr, "#") ||
+		strings.HasPrefix(urlStr, "mailto:") ||
+		strings.HasPrefix(urlStr, "data:") {
+		return nil
+	}
+	urlStr = strings.TrimPrefix(urlStr, "./")
 
-		var absPath string
-		if after, ok := strings.CutPrefix(urlStr, "/"); ok {
-			absPath = after // abs from repo root
+	var absPath string
+	if after, ok := strings.CutPrefix(urlStr, "/"); ok {
+		absPath = after
+	} else {
+		if baseDir == "" || baseDir == "." {
+			absPath = urlStr
 		} else {
-			// relative to repo location
-			if baseDir == "" || baseDir == "." {
-				absPath = urlStr
-			} else {
-				absPath = path.Join(baseDir, urlStr)
-			}
+			absPath = path.Join(baseDir, urlStr)
 		}
+	}
 
-		absPath = path.Clean(absPath)
-		absPath = strings.TrimPrefix(absPath, "/")
+	absPath = strings.TrimPrefix(path.Clean(absPath), "/")
 
-		// FIXME:hardcoded link
-		*dest = fmt.Appendf(nil, "/%s/blob/HEAD/%s?raw=true",
-			url.PathEscape(repoName), absPath)
+	// FIXME: hardcoded ref and link
+	return fmt.Appendf(nil, "/%s/blob/HEAD/%s?raw=true", url.PathEscape(repoName), absPath)
+}
 
-		return ast.WalkContinue, nil
+var imgSrcRe = regexp.MustCompile(`src="([^"]*)"`)
+
+func (t *relinkTransformer) rewriteSrc(buf []byte, repoName, baseDir string) []byte {
+	return imgSrcRe.ReplaceAllFunc(buf, func(match []byte) []byte {
+		src := imgSrcRe.FindSubmatch(match)[1]
+		rewritten := t.rewriteDest(src, repoName, baseDir)
+		if rewritten == nil {
+			return match
+		}
+		return append([]byte(`src="`), append(rewritten, '"')...)
 	})
 }