matrix-prometheus/vendor/maunium.net/go/mautrix/format/mdspoiler.go

166 lines
3.9 KiB
Go

// Copyright (c) 2022 Tulir Asokan
//
// This Source Code Form is subject to the terms of the Mozilla Public
// License, v. 2.0. If a copy of the MPL was not distributed with this
// file, You can obtain one at http://mozilla.org/MPL/2.0/.
package format
import (
"bytes"
"fmt"
stdhtml "html"
"regexp"
"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"
)
var astKindSpoiler = ast.NewNodeKind("Spoiler")
type astSpoiler struct {
ast.BaseInline
reason string
}
func (n *astSpoiler) Dump(source []byte, level int) {
ast.DumpHelper(n, source, level, nil, nil)
}
func (n *astSpoiler) Kind() ast.NodeKind {
return astKindSpoiler
}
type spoilerDelimiterProcessor struct{}
var defaultSpoilerDelimiterProcessor = &spoilerDelimiterProcessor{}
func (p *spoilerDelimiterProcessor) IsDelimiter(b byte) bool {
return b == '|'
}
func (p *spoilerDelimiterProcessor) CanOpenCloser(opener, closer *parser.Delimiter) bool {
return opener.Char == closer.Char
}
func (p *spoilerDelimiterProcessor) OnMatch(consumes int) ast.Node {
return &astSpoiler{}
}
type spoilerParser struct{}
var defaultSpoilerParser = &spoilerParser{}
func newSpoilerParser() parser.InlineParser {
return defaultSpoilerParser
}
func (s *spoilerParser) Trigger() []byte {
return []byte{'|'}
}
var spoilerRegex = regexp.MustCompile(`^\|\|(?:([^|]+?)\|[^|])?`)
var spoilerContextKey = parser.NewContextKey()
type spoilerContext struct {
reason string
segment text.Segment
bottom *parser.Delimiter
}
func (s *spoilerParser) Parse(parent ast.Node, block text.Reader, pc parser.Context) ast.Node {
line, segment := block.PeekLine()
if spoiler, ok := pc.Get(spoilerContextKey).(spoilerContext); ok {
if !bytes.HasPrefix(line, []byte("||")) {
return nil
}
block.Advance(2)
pc.Set(spoilerContextKey, nil)
n := &astSpoiler{
BaseInline: ast.BaseInline{},
reason: spoiler.reason,
}
parser.ProcessDelimiters(spoiler.bottom, pc)
var c ast.Node = spoiler.bottom
for c != nil {
next := c.NextSibling()
parent.RemoveChild(parent, c)
n.AppendChild(n, c)
c = next
}
return n
}
match := spoilerRegex.FindSubmatch(line)
if match == nil {
return nil
}
length := 2
reason := string(match[1])
if len(reason) > 0 {
length += len(match[1]) + 1
}
block.Advance(length)
delim := parser.NewDelimiter(true, false, length, '|', defaultSpoilerDelimiterProcessor)
pc.Set(spoilerContextKey, spoilerContext{
reason: reason,
segment: segment,
bottom: delim,
})
return delim
}
func (s *spoilerParser) CloseBlock(parent ast.Node, pc parser.Context) {
// nothing to do
}
type spoilerHTMLRenderer struct {
html.Config
}
func newSpoilerHTMLRenderer(opts ...html.Option) renderer.NodeRenderer {
r := &spoilerHTMLRenderer{
Config: html.NewConfig(),
}
for _, opt := range opts {
opt.SetHTMLOption(&r.Config)
}
return r
}
func (r *spoilerHTMLRenderer) RegisterFuncs(reg renderer.NodeRendererFuncRegisterer) {
reg.Register(astKindSpoiler, r.renderSpoiler)
}
func (r *spoilerHTMLRenderer) renderSpoiler(w util.BufWriter, source []byte, n ast.Node, entering bool) (ast.WalkStatus, error) {
if entering {
node := n.(*astSpoiler)
if len(node.reason) == 0 {
_, _ = w.WriteString("<span data-mx-spoiler>")
} else {
_, _ = fmt.Fprintf(w, `<span data-mx-spoiler="%s">`, stdhtml.EscapeString(node.reason))
}
} else {
_, _ = w.WriteString("</span>")
}
return ast.WalkContinue, nil
}
type extSpoiler struct{}
// ExtensionSpoiler is an extension that allow you to use spoiler expression like '~~text~~' .
var ExtensionSpoiler = &extSpoiler{}
func (e *extSpoiler) Extend(m goldmark.Markdown) {
m.Parser().AddOptions(parser.WithInlineParsers(
util.Prioritized(newSpoilerParser(), 500),
))
m.Renderer().AddOptions(renderer.WithNodeRenderers(
util.Prioritized(newSpoilerHTMLRenderer(), 500),
))
}