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, "section": true, "source": 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)(?:\s.*|>.*|/>.*|)\n?$`) var htmlBlockType1CloseRegexp = regexp.MustCompile(`(?i)^.*</(?:script|pre|style)>.*`) var htmlBlockType2OpenRegexp = regexp.MustCompile(`^[ ]{0,3}<!\-\-`) var htmlBlockType2Close = []byte{'-', '-', '>'} var htmlBlockType3OpenRegexp = regexp.MustCompile(`^[ ]{0,3}<\?`) var htmlBlockType3Close = []byte{'?', '>'} var htmlBlockType4OpenRegexp = regexp.MustCompile(`^[ ]{0,3}<![A-Z]+.*\n?$`) var htmlBlockType4Close = []byte{'>'} var htmlBlockType5OpenRegexp = regexp.MustCompile(`^[ ]{0,3}<\!\[CDATA\[`) var htmlBlockType5Close = []byte{']', ']', '>'} var htmlBlockType6Regexp = regexp.MustCompile(`^[ ]{0,3}</?([a-zA-Z0-9]+)(?:\s.*|>.*|/>.*|)\n?$`) var htmlBlockType7Regexp = regexp.MustCompile(`^[ ]{0,3}<(/)?([a-zA-Z0-9\-]+)(` + attributePattern + `*)(:?>|/>)\s*\n?$`) 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() - 1) 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() - 1) 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() - 1) return Close } case ast.HTMLBlockType6, ast.HTMLBlockType7: if util.IsBlank(line) { return Close } } node.Lines().Append(segment) reader.Advance(segment.Len() - 1) 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 }