854 lines
20 KiB
Go
854 lines
20 KiB
Go
//
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// Blackfriday Markdown Processor
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// Available at http://github.com/russross/blackfriday
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//
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// Copyright © 2011 Russ Ross <russ@russross.com>.
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// Distributed under the Simplified BSD License.
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// See README.md for details.
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//
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//
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//
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// HTML rendering backend
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//
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//
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package blackfriday
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import (
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"bytes"
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"fmt"
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"regexp"
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"strconv"
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"strings"
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)
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// Html renderer configuration options.
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const (
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HTML_SKIP_HTML = 1 << iota // skip preformatted HTML blocks
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HTML_SKIP_STYLE // skip embedded <style> elements
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HTML_SKIP_IMAGES // skip embedded images
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HTML_SKIP_LINKS // skip all links
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HTML_SKIP_SCRIPT // skip embedded <script> elements
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HTML_SAFELINK // only link to trusted protocols
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HTML_TOC // generate a table of contents
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HTML_OMIT_CONTENTS // skip the main contents (for a standalone table of contents)
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HTML_COMPLETE_PAGE // generate a complete HTML page
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HTML_GITHUB_BLOCKCODE // use github fenced code rendering rules
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HTML_USE_XHTML // generate XHTML output instead of HTML
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HTML_USE_SMARTYPANTS // enable smart punctuation substitutions
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HTML_SMARTYPANTS_FRACTIONS // enable smart fractions (with HTML_USE_SMARTYPANTS)
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HTML_SMARTYPANTS_LATEX_DASHES // enable LaTeX-style dashes (with HTML_USE_SMARTYPANTS)
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)
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var (
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tags = []string{
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"b",
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"blockquote",
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"code",
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"del",
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"dd",
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"dl",
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"dt",
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"em",
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"h1",
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"h2",
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"h3",
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"h4",
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"h5",
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"h6",
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"i",
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"kbd",
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"li",
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"ol",
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"p",
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"pre",
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"s",
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"sup",
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"sub",
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"strong",
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"strike",
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"ul",
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}
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urlRe = `((https?|ftp):\/\/|\/)[-A-Za-z0-9+&@#\/%?=~_|!:,.;\(\)]+`
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tagWhitelist = regexp.MustCompile(`^(<\/?(` + strings.Join(tags, "|") + `)>|<(br|hr)\s?\/?>)$`)
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anchorClean = regexp.MustCompile(`^(<a\shref="` + urlRe + `"(\stitle="[^"<>]+")?\s?>|<\/a>)$`)
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imgClean = regexp.MustCompile(`^(<img\ssrc="` + urlRe + `"(\swidth="\d{1,3}")?(\sheight="\d{1,3}")?(\salt="[^"<>]*")?(\stitle="[^"<>]*")?\s?\/?>)$`)
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)
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// Html is a type that implements the Renderer interface for HTML output.
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//
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// Do not create this directly, instead use the HtmlRenderer function.
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type Html struct {
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flags int // HTML_* options
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closeTag string // how to end singleton tags: either " />\n" or ">\n"
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title string // document title
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css string // optional css file url (used with HTML_COMPLETE_PAGE)
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// table of contents data
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tocMarker int
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headerCount int
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currentLevel int
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toc *bytes.Buffer
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smartypants *smartypantsRenderer
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}
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const (
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xhtmlClose = " />\n"
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htmlClose = ">\n"
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)
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// HtmlRenderer creates and configures an Html object, which
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// satisfies the Renderer interface.
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//
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// flags is a set of HTML_* options ORed together.
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// title is the title of the document, and css is a URL for the document's
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// stylesheet.
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// title and css are only used when HTML_COMPLETE_PAGE is selected.
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func HtmlRenderer(flags int, title string, css string) Renderer {
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// configure the rendering engine
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closeTag := htmlClose
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if flags&HTML_USE_XHTML != 0 {
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closeTag = xhtmlClose
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}
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return &Html{
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flags: flags,
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closeTag: closeTag,
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title: title,
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css: css,
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headerCount: 0,
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currentLevel: 0,
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toc: new(bytes.Buffer),
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smartypants: smartypants(flags),
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}
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}
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func attrEscape(out *bytes.Buffer, src []byte) {
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org := 0
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for i, ch := range src {
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// using if statements is a bit faster than a switch statement.
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// as the compiler improves, this should be unnecessary
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// this is only worthwhile because attrEscape is the single
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// largest CPU user in normal use
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if ch == '"' {
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if i > org {
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// copy all the normal characters since the last escape
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out.Write(src[org:i])
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}
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org = i + 1
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out.WriteString(""")
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continue
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}
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if ch == '&' {
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if i > org {
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out.Write(src[org:i])
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}
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org = i + 1
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out.WriteString("&")
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continue
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}
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if ch == '<' {
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if i > org {
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out.Write(src[org:i])
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}
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org = i + 1
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out.WriteString("<")
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continue
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}
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if ch == '>' {
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if i > org {
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out.Write(src[org:i])
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}
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org = i + 1
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out.WriteString(">")
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continue
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}
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}
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if org < len(src) {
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out.Write(src[org:])
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}
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}
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func (options *Html) GetFlags() int {
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return options.flags
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}
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func (options *Html) Header(out *bytes.Buffer, text func() bool, level int) {
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marker := out.Len()
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doubleSpace(out)
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if options.flags&HTML_TOC != 0 {
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// headerCount is incremented in htmlTocHeader
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out.WriteString(fmt.Sprintf("<h%d id=\"toc_%d\">", level, options.headerCount))
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} else {
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out.WriteString(fmt.Sprintf("<h%d>", level))
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}
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tocMarker := out.Len()
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if !text() {
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out.Truncate(marker)
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return
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}
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// are we building a table of contents?
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if options.flags&HTML_TOC != 0 {
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options.TocHeader(out.Bytes()[tocMarker:], level)
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}
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out.WriteString(fmt.Sprintf("</h%d>\n", level))
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}
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func (options *Html) BlockHtml(out *bytes.Buffer, text []byte) {
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if options.flags&HTML_SKIP_HTML != 0 {
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return
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}
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doubleSpace(out)
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out.Write(text)
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out.WriteByte('\n')
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}
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func (options *Html) HRule(out *bytes.Buffer) {
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doubleSpace(out)
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out.WriteString("<hr")
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out.WriteString(options.closeTag)
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}
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func (options *Html) BlockCode(out *bytes.Buffer, text []byte, lang string) {
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if options.flags&HTML_GITHUB_BLOCKCODE != 0 {
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options.BlockCodeGithub(out, text, lang)
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} else {
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options.BlockCodeNormal(out, text, lang)
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}
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}
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func (options *Html) BlockCodeNormal(out *bytes.Buffer, text []byte, lang string) {
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doubleSpace(out)
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// parse out the language names/classes
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count := 0
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for _, elt := range strings.Fields(lang) {
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if elt[0] == '.' {
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elt = elt[1:]
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}
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if len(elt) == 0 {
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continue
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}
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if count == 0 {
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out.WriteString("<pre><code class=\"")
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} else {
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out.WriteByte(' ')
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}
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attrEscape(out, []byte(elt))
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count++
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}
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if count == 0 {
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out.WriteString("<pre><code>")
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} else {
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out.WriteString("\">")
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}
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attrEscape(out, text)
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out.WriteString("</code></pre>\n")
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}
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// GitHub style code block:
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//
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// <pre lang="LANG"><code>
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// ...
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// </code></pre>
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//
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// Unlike other parsers, we store the language identifier in the <pre>,
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// and don't let the user generate custom classes.
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//
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// The language identifier in the <pre> block gets postprocessed and all
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// the code inside gets syntax highlighted with Pygments. This is much safer
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// than letting the user specify a CSS class for highlighting.
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//
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// Note that we only generate HTML for the first specifier.
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// E.g.
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// ~~~~ {.python .numbered} => <pre lang="python"><code>
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func (options *Html) BlockCodeGithub(out *bytes.Buffer, text []byte, lang string) {
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doubleSpace(out)
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// parse out the language name
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count := 0
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for _, elt := range strings.Fields(lang) {
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if elt[0] == '.' {
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elt = elt[1:]
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}
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if len(elt) == 0 {
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continue
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}
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out.WriteString("<pre lang=\"")
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attrEscape(out, []byte(elt))
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out.WriteString("\"><code>")
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count++
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break
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}
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if count == 0 {
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out.WriteString("<pre><code>")
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}
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attrEscape(out, text)
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out.WriteString("</code></pre>\n")
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}
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func (options *Html) BlockQuote(out *bytes.Buffer, text []byte) {
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doubleSpace(out)
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out.WriteString("<blockquote>\n")
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out.Write(text)
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out.WriteString("</blockquote>\n")
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}
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func (options *Html) Table(out *bytes.Buffer, header []byte, body []byte, columnData []int) {
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doubleSpace(out)
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out.WriteString("<table>\n<thead>\n")
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out.Write(header)
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out.WriteString("</thead>\n\n<tbody>\n")
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out.Write(body)
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out.WriteString("</tbody>\n</table>\n")
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}
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func (options *Html) TableRow(out *bytes.Buffer, text []byte) {
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doubleSpace(out)
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out.WriteString("<tr>\n")
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out.Write(text)
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out.WriteString("\n</tr>\n")
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}
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func (options *Html) TableHeaderCell(out *bytes.Buffer, text []byte, align int) {
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doubleSpace(out)
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switch align {
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case TABLE_ALIGNMENT_LEFT:
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out.WriteString("<th align=\"left\">")
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case TABLE_ALIGNMENT_RIGHT:
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out.WriteString("<th align=\"right\">")
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case TABLE_ALIGNMENT_CENTER:
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out.WriteString("<th align=\"center\">")
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default:
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out.WriteString("<th>")
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}
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out.Write(text)
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out.WriteString("</th>")
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}
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func (options *Html) TableCell(out *bytes.Buffer, text []byte, align int) {
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doubleSpace(out)
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switch align {
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case TABLE_ALIGNMENT_LEFT:
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out.WriteString("<td align=\"left\">")
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case TABLE_ALIGNMENT_RIGHT:
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out.WriteString("<td align=\"right\">")
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case TABLE_ALIGNMENT_CENTER:
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out.WriteString("<td align=\"center\">")
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default:
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out.WriteString("<td>")
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}
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out.Write(text)
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out.WriteString("</td>")
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}
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func (options *Html) Footnotes(out *bytes.Buffer, text func() bool) {
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out.WriteString("<div class=\"footnotes\">\n")
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options.HRule(out)
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options.List(out, text, LIST_TYPE_ORDERED)
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out.WriteString("</div>\n")
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}
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func (options *Html) FootnoteItem(out *bytes.Buffer, name, text []byte, flags int) {
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if flags&LIST_ITEM_CONTAINS_BLOCK != 0 || flags&LIST_ITEM_BEGINNING_OF_LIST != 0 {
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doubleSpace(out)
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}
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out.WriteString(`<li id="fn:`)
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out.Write(slugify(name))
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out.WriteString(`">`)
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out.Write(text)
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out.WriteString("</li>\n")
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}
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func (options *Html) List(out *bytes.Buffer, text func() bool, flags int) {
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marker := out.Len()
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doubleSpace(out)
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if flags&LIST_TYPE_ORDERED != 0 {
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out.WriteString("<ol>")
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} else {
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out.WriteString("<ul>")
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}
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if !text() {
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out.Truncate(marker)
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return
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}
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if flags&LIST_TYPE_ORDERED != 0 {
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out.WriteString("</ol>\n")
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} else {
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out.WriteString("</ul>\n")
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}
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}
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func (options *Html) ListItem(out *bytes.Buffer, text []byte, flags int) {
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if flags&LIST_ITEM_CONTAINS_BLOCK != 0 || flags&LIST_ITEM_BEGINNING_OF_LIST != 0 {
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doubleSpace(out)
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}
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out.WriteString("<li>")
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out.Write(text)
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out.WriteString("</li>\n")
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}
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func (options *Html) Paragraph(out *bytes.Buffer, text func() bool) {
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marker := out.Len()
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doubleSpace(out)
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out.WriteString("<p>")
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if !text() {
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out.Truncate(marker)
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return
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}
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out.WriteString("</p>\n")
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}
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func (options *Html) AutoLink(out *bytes.Buffer, link []byte, kind int) {
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if options.flags&HTML_SAFELINK != 0 && !isSafeLink(link) && kind != LINK_TYPE_EMAIL {
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// mark it but don't link it if it is not a safe link: no smartypants
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out.WriteString("<tt>")
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attrEscape(out, link)
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out.WriteString("</tt>")
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return
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}
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out.WriteString("<a href=\"")
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if kind == LINK_TYPE_EMAIL {
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out.WriteString("mailto:")
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}
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attrEscape(out, link)
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out.WriteString("\">")
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// Pretty print: if we get an email address as
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// an actual URI, e.g. `mailto:foo@bar.com`, we don't
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// want to print the `mailto:` prefix
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switch {
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case bytes.HasPrefix(link, []byte("mailto://")):
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attrEscape(out, link[len("mailto://"):])
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case bytes.HasPrefix(link, []byte("mailto:")):
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attrEscape(out, link[len("mailto:"):])
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default:
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attrEscape(out, link)
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}
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out.WriteString("</a>")
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}
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func (options *Html) CodeSpan(out *bytes.Buffer, text []byte) {
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out.WriteString("<code>")
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attrEscape(out, text)
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out.WriteString("</code>")
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}
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func (options *Html) DoubleEmphasis(out *bytes.Buffer, text []byte) {
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out.WriteString("<strong>")
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out.Write(text)
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out.WriteString("</strong>")
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}
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func (options *Html) Emphasis(out *bytes.Buffer, text []byte) {
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if len(text) == 0 {
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return
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}
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out.WriteString("<em>")
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out.Write(text)
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out.WriteString("</em>")
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}
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func (options *Html) Image(out *bytes.Buffer, link []byte, title []byte, alt []byte) {
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if options.flags&HTML_SKIP_IMAGES != 0 {
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return
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}
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out.WriteString("<img src=\"")
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attrEscape(out, link)
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out.WriteString("\" alt=\"")
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if len(alt) > 0 {
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attrEscape(out, alt)
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}
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if len(title) > 0 {
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out.WriteString("\" title=\"")
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attrEscape(out, title)
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}
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out.WriteByte('"')
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out.WriteString(options.closeTag)
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return
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}
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func (options *Html) LineBreak(out *bytes.Buffer) {
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out.WriteString("<br")
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out.WriteString(options.closeTag)
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}
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func (options *Html) Link(out *bytes.Buffer, link []byte, title []byte, content []byte) {
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if options.flags&HTML_SKIP_LINKS != 0 {
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// write the link text out but don't link it, just mark it with typewriter font
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out.WriteString("<tt>")
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attrEscape(out, content)
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out.WriteString("</tt>")
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return
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}
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if options.flags&HTML_SAFELINK != 0 && !isSafeLink(link) {
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// write the link text out but don't link it, just mark it with typewriter font
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out.WriteString("<tt>")
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attrEscape(out, content)
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out.WriteString("</tt>")
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return
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}
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out.WriteString("<a href=\"")
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attrEscape(out, link)
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if len(title) > 0 {
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out.WriteString("\" title=\"")
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attrEscape(out, title)
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}
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out.WriteString("\">")
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out.Write(content)
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out.WriteString("</a>")
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return
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}
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func (options *Html) RawHtmlTag(out *bytes.Buffer, text []byte) {
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if options.flags&HTML_SKIP_HTML != 0 {
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return
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}
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if options.flags&HTML_SKIP_STYLE != 0 && isHtmlTag(text, "style") {
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return
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}
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if options.flags&HTML_SKIP_LINKS != 0 && isHtmlTag(text, "a") {
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return
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}
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if options.flags&HTML_SKIP_IMAGES != 0 && isHtmlTag(text, "img") {
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return
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}
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if options.flags&HTML_SKIP_SCRIPT != 0 && isHtmlTag(text, "script") {
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return
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}
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out.Write(text)
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}
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func (options *Html) TripleEmphasis(out *bytes.Buffer, text []byte) {
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out.WriteString("<strong><em>")
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out.Write(text)
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out.WriteString("</em></strong>")
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}
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|
|
func (options *Html) StrikeThrough(out *bytes.Buffer, text []byte) {
|
|
out.WriteString("<del>")
|
|
out.Write(text)
|
|
out.WriteString("</del>")
|
|
}
|
|
|
|
func (options *Html) FootnoteRef(out *bytes.Buffer, ref []byte, id int) {
|
|
slug := slugify(ref)
|
|
out.WriteString(`<sup class="footnote-ref" id="fnref:`)
|
|
out.Write(slug)
|
|
out.WriteString(`"><a rel="footnote" href="#fn:`)
|
|
out.Write(slug)
|
|
out.WriteString(`">`)
|
|
out.WriteString(strconv.Itoa(id))
|
|
out.WriteString(`</a></sup>`)
|
|
}
|
|
|
|
func (options *Html) Entity(out *bytes.Buffer, entity []byte) {
|
|
out.Write(entity)
|
|
}
|
|
|
|
func (options *Html) NormalText(out *bytes.Buffer, text []byte) {
|
|
if options.flags&HTML_USE_SMARTYPANTS != 0 {
|
|
options.Smartypants(out, text)
|
|
} else {
|
|
attrEscape(out, text)
|
|
}
|
|
}
|
|
|
|
func (options *Html) Smartypants(out *bytes.Buffer, text []byte) {
|
|
smrt := smartypantsData{false, false}
|
|
|
|
// first do normal entity escaping
|
|
var escaped bytes.Buffer
|
|
attrEscape(&escaped, text)
|
|
text = escaped.Bytes()
|
|
|
|
mark := 0
|
|
for i := 0; i < len(text); i++ {
|
|
if action := options.smartypants[text[i]]; action != nil {
|
|
if i > mark {
|
|
out.Write(text[mark:i])
|
|
}
|
|
|
|
previousChar := byte(0)
|
|
if i > 0 {
|
|
previousChar = text[i-1]
|
|
}
|
|
i += action(out, &smrt, previousChar, text[i:])
|
|
mark = i + 1
|
|
}
|
|
}
|
|
|
|
if mark < len(text) {
|
|
out.Write(text[mark:])
|
|
}
|
|
}
|
|
|
|
func (options *Html) DocumentHeader(out *bytes.Buffer) {
|
|
if options.flags&HTML_COMPLETE_PAGE == 0 {
|
|
return
|
|
}
|
|
|
|
ending := ""
|
|
if options.flags&HTML_USE_XHTML != 0 {
|
|
out.WriteString("<!DOCTYPE html PUBLIC \"-//W3C//DTD XHTML 1.0 Transitional//EN\" ")
|
|
out.WriteString("\"http://www.w3.org/TR/xhtml1/DTD/xhtml1-transitional.dtd\">\n")
|
|
out.WriteString("<html xmlns=\"http://www.w3.org/1999/xhtml\">\n")
|
|
ending = " /"
|
|
} else {
|
|
out.WriteString("<!DOCTYPE html>\n")
|
|
out.WriteString("<html>\n")
|
|
}
|
|
out.WriteString("<head>\n")
|
|
out.WriteString(" <title>")
|
|
options.NormalText(out, []byte(options.title))
|
|
out.WriteString("</title>\n")
|
|
out.WriteString(" <meta name=\"GENERATOR\" content=\"Blackfriday Markdown Processor v")
|
|
out.WriteString(VERSION)
|
|
out.WriteString("\"")
|
|
out.WriteString(ending)
|
|
out.WriteString(">\n")
|
|
out.WriteString(" <meta charset=\"utf-8\"")
|
|
out.WriteString(ending)
|
|
out.WriteString(">\n")
|
|
if options.css != "" {
|
|
out.WriteString(" <link rel=\"stylesheet\" type=\"text/css\" href=\"")
|
|
attrEscape(out, []byte(options.css))
|
|
out.WriteString("\"")
|
|
out.WriteString(ending)
|
|
out.WriteString(">\n")
|
|
}
|
|
out.WriteString("</head>\n")
|
|
out.WriteString("<body>\n")
|
|
|
|
options.tocMarker = out.Len()
|
|
}
|
|
|
|
func (options *Html) DocumentFooter(out *bytes.Buffer) {
|
|
// finalize and insert the table of contents
|
|
if options.flags&HTML_TOC != 0 {
|
|
options.TocFinalize()
|
|
|
|
// now we have to insert the table of contents into the document
|
|
var temp bytes.Buffer
|
|
|
|
// start by making a copy of everything after the document header
|
|
temp.Write(out.Bytes()[options.tocMarker:])
|
|
|
|
// now clear the copied material from the main output buffer
|
|
out.Truncate(options.tocMarker)
|
|
|
|
// corner case spacing issue
|
|
if options.flags&HTML_COMPLETE_PAGE != 0 {
|
|
out.WriteByte('\n')
|
|
}
|
|
|
|
// insert the table of contents
|
|
out.WriteString("<nav>\n")
|
|
out.Write(options.toc.Bytes())
|
|
out.WriteString("</nav>\n")
|
|
|
|
// corner case spacing issue
|
|
if options.flags&HTML_COMPLETE_PAGE == 0 && options.flags&HTML_OMIT_CONTENTS == 0 {
|
|
out.WriteByte('\n')
|
|
}
|
|
|
|
// write out everything that came after it
|
|
if options.flags&HTML_OMIT_CONTENTS == 0 {
|
|
out.Write(temp.Bytes())
|
|
}
|
|
}
|
|
|
|
if options.flags&HTML_COMPLETE_PAGE != 0 {
|
|
out.WriteString("\n</body>\n")
|
|
out.WriteString("</html>\n")
|
|
}
|
|
|
|
}
|
|
|
|
func (options *Html) TocHeader(text []byte, level int) {
|
|
for level > options.currentLevel {
|
|
switch {
|
|
case bytes.HasSuffix(options.toc.Bytes(), []byte("</li>\n")):
|
|
// this sublist can nest underneath a header
|
|
size := options.toc.Len()
|
|
options.toc.Truncate(size - len("</li>\n"))
|
|
|
|
case options.currentLevel > 0:
|
|
options.toc.WriteString("<li>")
|
|
}
|
|
if options.toc.Len() > 0 {
|
|
options.toc.WriteByte('\n')
|
|
}
|
|
options.toc.WriteString("<ul>\n")
|
|
options.currentLevel++
|
|
}
|
|
|
|
for level < options.currentLevel {
|
|
options.toc.WriteString("</ul>")
|
|
if options.currentLevel > 1 {
|
|
options.toc.WriteString("</li>\n")
|
|
}
|
|
options.currentLevel--
|
|
}
|
|
|
|
options.toc.WriteString("<li><a href=\"#toc_")
|
|
options.toc.WriteString(strconv.Itoa(options.headerCount))
|
|
options.toc.WriteString("\">")
|
|
options.headerCount++
|
|
|
|
options.toc.Write(text)
|
|
|
|
options.toc.WriteString("</a></li>\n")
|
|
}
|
|
|
|
func (options *Html) TocFinalize() {
|
|
for options.currentLevel > 1 {
|
|
options.toc.WriteString("</ul></li>\n")
|
|
options.currentLevel--
|
|
}
|
|
|
|
if options.currentLevel > 0 {
|
|
options.toc.WriteString("</ul>\n")
|
|
}
|
|
}
|
|
|
|
func isHtmlTag(tag []byte, tagname string) bool {
|
|
found, _ := findHtmlTagPos(tag, tagname)
|
|
return found
|
|
}
|
|
|
|
// Look for a character, but ignore it when it's in any kind of quotes, it
|
|
// might be JavaScript
|
|
func skipUntilCharIgnoreQuotes(html []byte, start int, char byte) int {
|
|
inSingleQuote := false
|
|
inDoubleQuote := false
|
|
inGraveQuote := false
|
|
i := start
|
|
for i < len(html) {
|
|
switch {
|
|
case html[i] == char && !inSingleQuote && !inDoubleQuote && !inGraveQuote:
|
|
return i
|
|
case html[i] == '\'':
|
|
inSingleQuote = !inSingleQuote
|
|
case html[i] == '"':
|
|
inDoubleQuote = !inDoubleQuote
|
|
case html[i] == '`':
|
|
inGraveQuote = !inGraveQuote
|
|
}
|
|
i++
|
|
}
|
|
return start
|
|
}
|
|
|
|
func findHtmlTagPos(tag []byte, tagname string) (bool, int) {
|
|
i := 0
|
|
if i < len(tag) && tag[0] != '<' {
|
|
return false, -1
|
|
}
|
|
i++
|
|
i = skipSpace(tag, i)
|
|
|
|
if i < len(tag) && tag[i] == '/' {
|
|
i++
|
|
}
|
|
|
|
i = skipSpace(tag, i)
|
|
j := 0
|
|
for ; i < len(tag); i, j = i+1, j+1 {
|
|
if j >= len(tagname) {
|
|
break
|
|
}
|
|
|
|
if strings.ToLower(string(tag[i]))[0] != tagname[j] {
|
|
return false, -1
|
|
}
|
|
}
|
|
|
|
if i == len(tag) {
|
|
return false, -1
|
|
}
|
|
|
|
rightAngle := skipUntilCharIgnoreQuotes(tag, i, '>')
|
|
if rightAngle > i {
|
|
return true, rightAngle
|
|
}
|
|
|
|
return false, -1
|
|
}
|
|
|
|
func sanitizeHtml(html []byte) []byte {
|
|
var result []byte
|
|
for string(html) != "" {
|
|
skip, tag, rest := findHtmlTag(html)
|
|
html = rest
|
|
result = append(result, skip...)
|
|
result = append(result, sanitizeTag(tag)...)
|
|
}
|
|
return append(result, []byte("\n")...)
|
|
}
|
|
|
|
func sanitizeTag(tag []byte) []byte {
|
|
if tagWhitelist.Match(tag) || anchorClean.Match(tag) || imgClean.Match(tag) {
|
|
return tag
|
|
} else {
|
|
return []byte("")
|
|
}
|
|
}
|
|
|
|
func skipUntilChar(text []byte, start int, char byte) int {
|
|
i := start
|
|
for i < len(text) && text[i] != char {
|
|
i++
|
|
}
|
|
return i
|
|
}
|
|
|
|
func findHtmlTag(html []byte) (skip, tag, rest []byte) {
|
|
start := skipUntilChar(html, 0, '<')
|
|
rightAngle := skipUntilCharIgnoreQuotes(html, start, '>')
|
|
if rightAngle > start {
|
|
skip = html[0:start]
|
|
tag = html[start : rightAngle+1]
|
|
rest = html[rightAngle+1:]
|
|
return
|
|
}
|
|
|
|
return []byte(""), []byte(""), []byte("")
|
|
}
|
|
|
|
func skipSpace(tag []byte, i int) int {
|
|
for i < len(tag) && isspace(tag[i]) {
|
|
i++
|
|
}
|
|
return i
|
|
}
|
|
|
|
func doubleSpace(out *bytes.Buffer) {
|
|
if out.Len() > 0 {
|
|
out.WriteByte('\n')
|
|
}
|
|
}
|