forgejo-federation/modules/markup/common/footnote.go
Earl Warren 7b79294684
[GITEA] Revert "Make user-content-* consistent with github (#26388)"
Refs: https://codeberg.org/forgejo/forgejo/issues/1943

This reverts commit d41aee1d1e.

(cherry picked from commit d29ec91e91362b0657edee631f12cf1d55ba7a2c)
(cherry picked from commit a0f5a9750e81c5e3992365f61b8cb9ab99413139)
(cherry picked from commit 26bfc3bc14b7f07d11819b11251c716a8cf7eaf1)
(cherry picked from commit 59f57a1bc9d97d76319a6e2d8b7a336a9a480bb4)
(cherry picked from commit ce3b73a033d6f8b617b01f4f9fb33d70abf714aa)
(cherry picked from commit 2c426c28af18b69305bc8d71c389f21432fd8c3d)
(cherry picked from commit 155a08bca71cb90e753b73cbcd522e4f5064d980)
(cherry picked from commit 8934fd895c875135b4eb41dc2a1e2e456faf10da)
2024-02-05 16:09:41 +01:00

498 lines
13 KiB
Go

// 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),
))
}