gotosocial/vendor/github.com/yuin/goldmark/parser/html_block.go

229 lines
6.3 KiB
Go

package parser
import (
"bytes"
"regexp"
"strings"
"github.com/yuin/goldmark/ast"
"github.com/yuin/goldmark/text"
"github.com/yuin/goldmark/util"
)
var allowedBlockTags = map[string]bool{
"address": true,
"article": true,
"aside": true,
"base": true,
"basefont": true,
"blockquote": true,
"body": true,
"caption": true,
"center": true,
"col": true,
"colgroup": true,
"dd": true,
"details": true,
"dialog": true,
"dir": true,
"div": true,
"dl": true,
"dt": true,
"fieldset": true,
"figcaption": true,
"figure": true,
"footer": true,
"form": true,
"frame": true,
"frameset": true,
"h1": true,
"h2": true,
"h3": true,
"h4": true,
"h5": true,
"h6": true,
"head": true,
"header": true,
"hr": true,
"html": true,
"iframe": true,
"legend": true,
"li": true,
"link": true,
"main": true,
"menu": true,
"menuitem": true,
"meta": true,
"nav": true,
"noframes": true,
"ol": true,
"optgroup": true,
"option": true,
"p": true,
"param": true,
"search": true,
"section": true,
"summary": true,
"table": true,
"tbody": true,
"td": true,
"tfoot": true,
"th": true,
"thead": true,
"title": true,
"tr": true,
"track": true,
"ul": true,
}
var htmlBlockType1OpenRegexp = regexp.MustCompile(`(?i)^[ ]{0,3}<(script|pre|style|textarea)(?:\s.*|>.*|/>.*|)(?:\r\n|\n)?$`) //nolint:golint,lll
var htmlBlockType1CloseRegexp = regexp.MustCompile(`(?i)^.*</(?:script|pre|style|textarea)>.*`)
var htmlBlockType2OpenRegexp = regexp.MustCompile(`^[ ]{0,3}<!\-\-`)
var htmlBlockType2Close = []byte{'-', '-', '>'}
var htmlBlockType3OpenRegexp = regexp.MustCompile(`^[ ]{0,3}<\?`)
var htmlBlockType3Close = []byte{'?', '>'}
var htmlBlockType4OpenRegexp = regexp.MustCompile(`^[ ]{0,3}<![A-Z]+.*(?:\r\n|\n)?$`)
var htmlBlockType4Close = []byte{'>'}
var htmlBlockType5OpenRegexp = regexp.MustCompile(`^[ ]{0,3}<\!\[CDATA\[`)
var htmlBlockType5Close = []byte{']', ']', '>'}
var htmlBlockType6Regexp = regexp.MustCompile(`^[ ]{0,3}<(?:/[ ]*)?([a-zA-Z]+[a-zA-Z0-9\-]*)(?:[ ].*|>.*|/>.*|)(?:\r\n|\n)?$`) //nolint:golint,lll
var htmlBlockType7Regexp = regexp.MustCompile(`^[ ]{0,3}<(/[ ]*)?([a-zA-Z]+[a-zA-Z0-9\-]*)(` + attributePattern + `*)[ ]*(?:>|/>)[ ]*(?:\r\n|\n)?$`) //nolint:golint,lll
type htmlBlockParser struct {
}
var defaultHTMLBlockParser = &htmlBlockParser{}
// NewHTMLBlockParser return a new BlockParser that can parse html
// blocks.
func NewHTMLBlockParser() BlockParser {
return defaultHTMLBlockParser
}
func (b *htmlBlockParser) Trigger() []byte {
return []byte{'<'}
}
func (b *htmlBlockParser) Open(parent ast.Node, reader text.Reader, pc Context) (ast.Node, State) {
var node *ast.HTMLBlock
line, segment := reader.PeekLine()
last := pc.LastOpenedBlock().Node
if pos := pc.BlockOffset(); pos < 0 || line[pos] != '<' {
return nil, NoChildren
}
if m := htmlBlockType1OpenRegexp.FindSubmatchIndex(line); m != nil {
node = ast.NewHTMLBlock(ast.HTMLBlockType1)
} else if htmlBlockType2OpenRegexp.Match(line) {
node = ast.NewHTMLBlock(ast.HTMLBlockType2)
} else if htmlBlockType3OpenRegexp.Match(line) {
node = ast.NewHTMLBlock(ast.HTMLBlockType3)
} else if htmlBlockType4OpenRegexp.Match(line) {
node = ast.NewHTMLBlock(ast.HTMLBlockType4)
} else if htmlBlockType5OpenRegexp.Match(line) {
node = ast.NewHTMLBlock(ast.HTMLBlockType5)
} else if match := htmlBlockType7Regexp.FindSubmatchIndex(line); match != nil {
isCloseTag := match[2] > -1 && bytes.Equal(line[match[2]:match[3]], []byte("/"))
hasAttr := match[6] != match[7]
tagName := strings.ToLower(string(line[match[4]:match[5]]))
_, ok := allowedBlockTags[tagName]
if ok {
node = ast.NewHTMLBlock(ast.HTMLBlockType6)
} else if tagName != "script" && tagName != "style" &&
tagName != "pre" && !ast.IsParagraph(last) && !(isCloseTag && hasAttr) { // type 7 can not interrupt paragraph
node = ast.NewHTMLBlock(ast.HTMLBlockType7)
}
}
if node == nil {
if match := htmlBlockType6Regexp.FindSubmatchIndex(line); match != nil {
tagName := string(line[match[2]:match[3]])
_, ok := allowedBlockTags[strings.ToLower(tagName)]
if ok {
node = ast.NewHTMLBlock(ast.HTMLBlockType6)
}
}
}
if node != nil {
reader.Advance(segment.Len() - util.TrimRightSpaceLength(line))
node.Lines().Append(segment)
return node, NoChildren
}
return nil, NoChildren
}
func (b *htmlBlockParser) Continue(node ast.Node, reader text.Reader, pc Context) State {
htmlBlock := node.(*ast.HTMLBlock)
lines := htmlBlock.Lines()
line, segment := reader.PeekLine()
var closurePattern []byte
switch htmlBlock.HTMLBlockType {
case ast.HTMLBlockType1:
if lines.Len() == 1 {
firstLine := lines.At(0)
if htmlBlockType1CloseRegexp.Match(firstLine.Value(reader.Source())) {
return Close
}
}
if htmlBlockType1CloseRegexp.Match(line) {
htmlBlock.ClosureLine = segment
reader.Advance(segment.Len() - util.TrimRightSpaceLength(line))
return Close
}
case ast.HTMLBlockType2:
closurePattern = htmlBlockType2Close
fallthrough
case ast.HTMLBlockType3:
if closurePattern == nil {
closurePattern = htmlBlockType3Close
}
fallthrough
case ast.HTMLBlockType4:
if closurePattern == nil {
closurePattern = htmlBlockType4Close
}
fallthrough
case ast.HTMLBlockType5:
if closurePattern == nil {
closurePattern = htmlBlockType5Close
}
if lines.Len() == 1 {
firstLine := lines.At(0)
if bytes.Contains(firstLine.Value(reader.Source()), closurePattern) {
return Close
}
}
if bytes.Contains(line, closurePattern) {
htmlBlock.ClosureLine = segment
reader.Advance(segment.Len())
return Close
}
case ast.HTMLBlockType6, ast.HTMLBlockType7:
if util.IsBlank(line) {
return Close
}
}
node.Lines().Append(segment)
reader.Advance(segment.Len() - util.TrimRightSpaceLength(line))
return Continue | NoChildren
}
func (b *htmlBlockParser) Close(node ast.Node, reader text.Reader, pc Context) {
// nothing to do
}
func (b *htmlBlockParser) CanInterruptParagraph() bool {
return true
}
func (b *htmlBlockParser) CanAcceptIndentedLine() bool {
return false
}