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authorDaniel Baumann <daniel.baumann@progress-linux.org>2024-10-11 10:27:00 +0000
committerDaniel Baumann <daniel.baumann@progress-linux.org>2024-10-11 10:27:00 +0000
commit65aa53fc52ff15efe54df4147564828d535837f8 (patch)
tree31c51dad04fdcca80e6d3043c8bd49d2f1a51f83 /modules/markup/common/footnote.go
parentInitial commit. (diff)
downloadforgejo-upstream.tar.xz
forgejo-upstream.zip
Adding upstream version 8.0.3.HEADupstream/8.0.3upstreamdebian
Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>
Diffstat (limited to 'modules/markup/common/footnote.go')
-rw-r--r--modules/markup/common/footnote.go498
1 files changed, 498 insertions, 0 deletions
diff --git a/modules/markup/common/footnote.go b/modules/markup/common/footnote.go
new file mode 100644
index 00000000..0e75e2ad
--- /dev/null
+++ b/modules/markup/common/footnote.go
@@ -0,0 +1,498 @@
+// Copyright 2019 Yusuke Inuzuka
+// Copyright 2019 The Gitea Authors. All rights reserved.
+// SPDX-License-Identifier: MIT
+
+// Most of what follows is a subtly changed version of github.com/yuin/goldmark/extension/footnote.go
+
+package common
+
+import (
+ "bytes"
+ "fmt"
+ "strconv"
+ "unicode"
+
+ "github.com/yuin/goldmark"
+ "github.com/yuin/goldmark/ast"
+ "github.com/yuin/goldmark/parser"
+ "github.com/yuin/goldmark/renderer"
+ "github.com/yuin/goldmark/renderer/html"
+ "github.com/yuin/goldmark/text"
+ "github.com/yuin/goldmark/util"
+)
+
+// CleanValue will clean a value to make it safe to be an id
+// This function is quite different from the original goldmark function
+// and more closely matches the output from the shurcooL sanitizer
+// In particular Unicode letters and numbers are a lot more than a-zA-Z0-9...
+func CleanValue(value []byte) []byte {
+ value = bytes.TrimSpace(value)
+ rs := bytes.Runes(value)
+ result := make([]rune, 0, len(rs))
+ needsDash := false
+ for _, r := range rs {
+ switch {
+ case unicode.IsLetter(r) || unicode.IsNumber(r) || r == '_':
+ if needsDash && len(result) > 0 {
+ result = append(result, '-')
+ }
+ needsDash = false
+ result = append(result, unicode.ToLower(r))
+ default:
+ needsDash = true
+ }
+ }
+ return []byte(string(result))
+}
+
+// Most of what follows is a subtly changed version of github.com/yuin/goldmark/extension/footnote.go
+
+// A FootnoteLink struct represents a link to a footnote of Markdown
+// (PHP Markdown Extra) text.
+type FootnoteLink struct {
+ ast.BaseInline
+ Index int
+ Name []byte
+}
+
+// Dump implements Node.Dump.
+func (n *FootnoteLink) Dump(source []byte, level int) {
+ m := map[string]string{}
+ m["Index"] = fmt.Sprintf("%v", n.Index)
+ m["Name"] = fmt.Sprintf("%v", n.Name)
+ ast.DumpHelper(n, source, level, m, nil)
+}
+
+// KindFootnoteLink is a NodeKind of the FootnoteLink node.
+var KindFootnoteLink = ast.NewNodeKind("GiteaFootnoteLink")
+
+// Kind implements Node.Kind.
+func (n *FootnoteLink) Kind() ast.NodeKind {
+ return KindFootnoteLink
+}
+
+// NewFootnoteLink returns a new FootnoteLink node.
+func NewFootnoteLink(index int, name []byte) *FootnoteLink {
+ return &FootnoteLink{
+ Index: index,
+ Name: name,
+ }
+}
+
+// A FootnoteBackLink struct represents a link to a footnote of Markdown
+// (PHP Markdown Extra) text.
+type FootnoteBackLink struct {
+ ast.BaseInline
+ Index int
+ Name []byte
+}
+
+// Dump implements Node.Dump.
+func (n *FootnoteBackLink) Dump(source []byte, level int) {
+ m := map[string]string{}
+ m["Index"] = fmt.Sprintf("%v", n.Index)
+ m["Name"] = fmt.Sprintf("%v", n.Name)
+ ast.DumpHelper(n, source, level, m, nil)
+}
+
+// KindFootnoteBackLink is a NodeKind of the FootnoteBackLink node.
+var KindFootnoteBackLink = ast.NewNodeKind("GiteaFootnoteBackLink")
+
+// Kind implements Node.Kind.
+func (n *FootnoteBackLink) Kind() ast.NodeKind {
+ return KindFootnoteBackLink
+}
+
+// NewFootnoteBackLink returns a new FootnoteBackLink node.
+func NewFootnoteBackLink(index int, name []byte) *FootnoteBackLink {
+ return &FootnoteBackLink{
+ Index: index,
+ Name: name,
+ }
+}
+
+// A Footnote struct represents a footnote of Markdown
+// (PHP Markdown Extra) text.
+type Footnote struct {
+ ast.BaseBlock
+ Ref []byte
+ Index int
+ Name []byte
+}
+
+// Dump implements Node.Dump.
+func (n *Footnote) Dump(source []byte, level int) {
+ m := map[string]string{}
+ m["Index"] = strconv.Itoa(n.Index)
+ m["Ref"] = string(n.Ref)
+ m["Name"] = string(n.Name)
+ ast.DumpHelper(n, source, level, m, nil)
+}
+
+// KindFootnote is a NodeKind of the Footnote node.
+var KindFootnote = ast.NewNodeKind("GiteaFootnote")
+
+// Kind implements Node.Kind.
+func (n *Footnote) Kind() ast.NodeKind {
+ return KindFootnote
+}
+
+// NewFootnote returns a new Footnote node.
+func NewFootnote(ref []byte) *Footnote {
+ return &Footnote{
+ Ref: ref,
+ Index: -1,
+ Name: ref,
+ }
+}
+
+// A FootnoteList struct represents footnotes of Markdown
+// (PHP Markdown Extra) text.
+type FootnoteList struct {
+ ast.BaseBlock
+ Count int
+}
+
+// Dump implements Node.Dump.
+func (n *FootnoteList) Dump(source []byte, level int) {
+ m := map[string]string{}
+ m["Count"] = fmt.Sprintf("%v", n.Count)
+ ast.DumpHelper(n, source, level, m, nil)
+}
+
+// KindFootnoteList is a NodeKind of the FootnoteList node.
+var KindFootnoteList = ast.NewNodeKind("GiteaFootnoteList")
+
+// Kind implements Node.Kind.
+func (n *FootnoteList) Kind() ast.NodeKind {
+ return KindFootnoteList
+}
+
+// NewFootnoteList returns a new FootnoteList node.
+func NewFootnoteList() *FootnoteList {
+ return &FootnoteList{
+ Count: 0,
+ }
+}
+
+var footnoteListKey = parser.NewContextKey()
+
+type footnoteBlockParser struct{}
+
+var defaultFootnoteBlockParser = &footnoteBlockParser{}
+
+// NewFootnoteBlockParser returns a new parser.BlockParser that can parse
+// footnotes of the Markdown(PHP Markdown Extra) text.
+func NewFootnoteBlockParser() parser.BlockParser {
+ return defaultFootnoteBlockParser
+}
+
+func (b *footnoteBlockParser) Trigger() []byte {
+ return []byte{'['}
+}
+
+func (b *footnoteBlockParser) Open(parent ast.Node, reader text.Reader, pc parser.Context) (ast.Node, parser.State) {
+ line, segment := reader.PeekLine()
+ pos := pc.BlockOffset()
+ if pos < 0 || line[pos] != '[' {
+ return nil, parser.NoChildren
+ }
+ pos++
+ if pos > len(line)-1 || line[pos] != '^' {
+ return nil, parser.NoChildren
+ }
+ open := pos + 1
+ closure := util.FindClosure(line[pos+1:], '[', ']', false, false) //nolint
+ closes := pos + 1 + closure
+ next := closes + 1
+ if closure > -1 {
+ if next >= len(line) || line[next] != ':' {
+ return nil, parser.NoChildren
+ }
+ } else {
+ return nil, parser.NoChildren
+ }
+ padding := segment.Padding
+ label := reader.Value(text.NewSegment(segment.Start+open-padding, segment.Start+closes-padding))
+ if util.IsBlank(label) {
+ return nil, parser.NoChildren
+ }
+ item := NewFootnote(label)
+
+ pos = next + 1 - padding
+ if pos >= len(line) {
+ reader.Advance(pos)
+ return item, parser.NoChildren
+ }
+ reader.AdvanceAndSetPadding(pos, padding)
+ return item, parser.HasChildren
+}
+
+func (b *footnoteBlockParser) Continue(node ast.Node, reader text.Reader, pc parser.Context) parser.State {
+ line, _ := reader.PeekLine()
+ if util.IsBlank(line) {
+ return parser.Continue | parser.HasChildren
+ }
+ childpos, padding := util.IndentPosition(line, reader.LineOffset(), 4)
+ if childpos < 0 {
+ return parser.Close
+ }
+ reader.AdvanceAndSetPadding(childpos, padding)
+ return parser.Continue | parser.HasChildren
+}
+
+func (b *footnoteBlockParser) Close(node ast.Node, reader text.Reader, pc parser.Context) {
+ var list *FootnoteList
+ if tlist := pc.Get(footnoteListKey); tlist != nil {
+ list = tlist.(*FootnoteList)
+ } else {
+ list = NewFootnoteList()
+ pc.Set(footnoteListKey, list)
+ node.Parent().InsertBefore(node.Parent(), node, list)
+ }
+ node.Parent().RemoveChild(node.Parent(), node)
+ list.AppendChild(list, node)
+}
+
+func (b *footnoteBlockParser) CanInterruptParagraph() bool {
+ return true
+}
+
+func (b *footnoteBlockParser) CanAcceptIndentedLine() bool {
+ return false
+}
+
+type footnoteParser struct{}
+
+var defaultFootnoteParser = &footnoteParser{}
+
+// NewFootnoteParser returns a new parser.InlineParser that can parse
+// footnote links of the Markdown(PHP Markdown Extra) text.
+func NewFootnoteParser() parser.InlineParser {
+ return defaultFootnoteParser
+}
+
+func (s *footnoteParser) Trigger() []byte {
+ // footnote syntax probably conflict with the image syntax.
+ // So we need trigger this parser with '!'.
+ return []byte{'!', '['}
+}
+
+func (s *footnoteParser) Parse(parent ast.Node, block text.Reader, pc parser.Context) ast.Node {
+ line, segment := block.PeekLine()
+ pos := 1
+ if len(line) > 0 && line[0] == '!' {
+ pos++
+ }
+ if pos >= len(line) || line[pos] != '^' {
+ return nil
+ }
+ pos++
+ if pos >= len(line) {
+ return nil
+ }
+ open := pos
+ closure := util.FindClosure(line[pos:], '[', ']', false, false) //nolint
+ if closure < 0 {
+ return nil
+ }
+ closes := pos + closure
+ value := block.Value(text.NewSegment(segment.Start+open, segment.Start+closes))
+ block.Advance(closes + 1)
+
+ var list *FootnoteList
+ if tlist := pc.Get(footnoteListKey); tlist != nil {
+ list = tlist.(*FootnoteList)
+ }
+ if list == nil {
+ return nil
+ }
+ index := 0
+ name := []byte{}
+ for def := list.FirstChild(); def != nil; def = def.NextSibling() {
+ d := def.(*Footnote)
+ if bytes.Equal(d.Ref, value) {
+ if d.Index < 0 {
+ list.Count++
+ d.Index = list.Count
+ val := CleanValue(d.Name)
+ if len(val) == 0 {
+ val = []byte(strconv.Itoa(d.Index))
+ }
+ d.Name = pc.IDs().Generate(val, KindFootnote)
+ }
+ index = d.Index
+ name = d.Name
+ break
+ }
+ }
+ if index == 0 {
+ return nil
+ }
+
+ return NewFootnoteLink(index, name)
+}
+
+type footnoteASTTransformer struct{}
+
+var defaultFootnoteASTTransformer = &footnoteASTTransformer{}
+
+// NewFootnoteASTTransformer returns a new parser.ASTTransformer that
+// insert a footnote list to the last of the document.
+func NewFootnoteASTTransformer() parser.ASTTransformer {
+ return defaultFootnoteASTTransformer
+}
+
+func (a *footnoteASTTransformer) Transform(node *ast.Document, reader text.Reader, pc parser.Context) {
+ var list *FootnoteList
+ if tlist := pc.Get(footnoteListKey); tlist != nil {
+ list = tlist.(*FootnoteList)
+ } else {
+ return
+ }
+ pc.Set(footnoteListKey, nil)
+ for footnote := list.FirstChild(); footnote != nil; {
+ container := footnote
+ next := footnote.NextSibling()
+ if fc := container.LastChild(); fc != nil && ast.IsParagraph(fc) {
+ container = fc
+ }
+ footnoteNode := footnote.(*Footnote)
+ index := footnoteNode.Index
+ name := footnoteNode.Name
+ if index < 0 {
+ list.RemoveChild(list, footnote)
+ } else {
+ container.AppendChild(container, NewFootnoteBackLink(index, name))
+ }
+ footnote = next
+ }
+ list.SortChildren(func(n1, n2 ast.Node) int {
+ if n1.(*Footnote).Index < n2.(*Footnote).Index {
+ return -1
+ }
+ return 1
+ })
+ if list.Count <= 0 {
+ list.Parent().RemoveChild(list.Parent(), list)
+ return
+ }
+
+ node.AppendChild(node, list)
+}
+
+// FootnoteHTMLRenderer is a renderer.NodeRenderer implementation that
+// renders FootnoteLink nodes.
+type FootnoteHTMLRenderer struct {
+ html.Config
+}
+
+// NewFootnoteHTMLRenderer returns a new FootnoteHTMLRenderer.
+func NewFootnoteHTMLRenderer(opts ...html.Option) renderer.NodeRenderer {
+ r := &FootnoteHTMLRenderer{
+ Config: html.NewConfig(),
+ }
+ for _, opt := range opts {
+ opt.SetHTMLOption(&r.Config)
+ }
+ return r
+}
+
+// RegisterFuncs implements renderer.NodeRenderer.RegisterFuncs.
+func (r *FootnoteHTMLRenderer) RegisterFuncs(reg renderer.NodeRendererFuncRegisterer) {
+ reg.Register(KindFootnoteLink, r.renderFootnoteLink)
+ reg.Register(KindFootnoteBackLink, r.renderFootnoteBackLink)
+ reg.Register(KindFootnote, r.renderFootnote)
+ reg.Register(KindFootnoteList, r.renderFootnoteList)
+}
+
+func (r *FootnoteHTMLRenderer) renderFootnoteLink(w util.BufWriter, source []byte, node ast.Node, entering bool) (ast.WalkStatus, error) {
+ if entering {
+ n := node.(*FootnoteLink)
+ is := strconv.Itoa(n.Index)
+ _, _ = w.WriteString(`<sup id="fnref:`)
+ _, _ = w.Write(n.Name)
+ _, _ = w.WriteString(`"><a href="#fn:`)
+ _, _ = w.Write(n.Name)
+ _, _ = w.WriteString(`" class="footnote-ref" role="doc-noteref">`)
+ _, _ = w.WriteString(is)
+ _, _ = w.WriteString(`</a></sup>`)
+ }
+ return ast.WalkContinue, nil
+}
+
+func (r *FootnoteHTMLRenderer) renderFootnoteBackLink(w util.BufWriter, source []byte, node ast.Node, entering bool) (ast.WalkStatus, error) {
+ if entering {
+ n := node.(*FootnoteBackLink)
+ _, _ = w.WriteString(` <a href="#fnref:`)
+ _, _ = w.Write(n.Name)
+ _, _ = w.WriteString(`" class="footnote-backref" role="doc-backlink">`)
+ _, _ = w.WriteString("&#x21a9;&#xfe0e;")
+ _, _ = w.WriteString(`</a>`)
+ }
+ return ast.WalkContinue, nil
+}
+
+func (r *FootnoteHTMLRenderer) renderFootnote(w util.BufWriter, source []byte, node ast.Node, entering bool) (ast.WalkStatus, error) {
+ n := node.(*Footnote)
+ if entering {
+ _, _ = w.WriteString(`<li id="fn:`)
+ _, _ = w.Write(n.Name)
+ _, _ = w.WriteString(`" role="doc-endnote"`)
+ if node.Attributes() != nil {
+ html.RenderAttributes(w, node, html.ListItemAttributeFilter)
+ }
+ _, _ = w.WriteString(">\n")
+ } else {
+ _, _ = w.WriteString("</li>\n")
+ }
+ return ast.WalkContinue, nil
+}
+
+func (r *FootnoteHTMLRenderer) renderFootnoteList(w util.BufWriter, source []byte, node ast.Node, entering bool) (ast.WalkStatus, error) {
+ tag := "div"
+ if entering {
+ _, _ = w.WriteString("<")
+ _, _ = w.WriteString(tag)
+ _, _ = w.WriteString(` class="footnotes" role="doc-endnotes"`)
+ if node.Attributes() != nil {
+ html.RenderAttributes(w, node, html.GlobalAttributeFilter)
+ }
+ _ = w.WriteByte('>')
+ if r.Config.XHTML {
+ _, _ = w.WriteString("\n<hr />\n")
+ } else {
+ _, _ = w.WriteString("\n<hr>\n")
+ }
+ _, _ = w.WriteString("<ol>\n")
+ } else {
+ _, _ = w.WriteString("</ol>\n")
+ _, _ = w.WriteString("</")
+ _, _ = w.WriteString(tag)
+ _, _ = w.WriteString(">\n")
+ }
+ return ast.WalkContinue, nil
+}
+
+type footnoteExtension struct{}
+
+// FootnoteExtension represents the Gitea Footnote
+var FootnoteExtension = &footnoteExtension{}
+
+// Extend extends the markdown converter with the Gitea Footnote parser
+func (e *footnoteExtension) Extend(m goldmark.Markdown) {
+ m.Parser().AddOptions(
+ parser.WithBlockParsers(
+ util.Prioritized(NewFootnoteBlockParser(), 999),
+ ),
+ parser.WithInlineParsers(
+ util.Prioritized(NewFootnoteParser(), 101),
+ ),
+ parser.WithASTTransformers(
+ util.Prioritized(NewFootnoteASTTransformer(), 999),
+ ),
+ )
+ m.Renderer().AddOptions(renderer.WithNodeRenderers(
+ util.Prioritized(NewFootnoteHTMLRenderer(), 500),
+ ))
+}