950 lines
24 KiB
Go
950 lines
24 KiB
Go
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//
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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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"io"
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"regexp"
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"strings"
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)
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// HTMLFlags control optional behavior of HTML renderer.
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type HTMLFlags int
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// HTML renderer configuration options.
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const (
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HTMLFlagsNone HTMLFlags = 0
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SkipHTML HTMLFlags = 1 << iota // Skip preformatted HTML blocks
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SkipImages // Skip embedded images
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SkipLinks // Skip all links
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Safelink // Only link to trusted protocols
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NofollowLinks // Only link with rel="nofollow"
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NoreferrerLinks // Only link with rel="noreferrer"
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NoopenerLinks // Only link with rel="noopener"
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HrefTargetBlank // Add a blank target
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CompletePage // Generate a complete HTML page
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UseXHTML // Generate XHTML output instead of HTML
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FootnoteReturnLinks // Generate a link at the end of a footnote to return to the source
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Smartypants // Enable smart punctuation substitutions
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SmartypantsFractions // Enable smart fractions (with Smartypants)
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SmartypantsDashes // Enable smart dashes (with Smartypants)
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SmartypantsLatexDashes // Enable LaTeX-style dashes (with Smartypants)
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SmartypantsAngledQuotes // Enable angled double quotes (with Smartypants) for double quotes rendering
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SmartypantsQuotesNBSP // Enable « French guillemets » (with Smartypants)
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TOC // Generate a table of contents
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)
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var (
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htmlTagRe = regexp.MustCompile("(?i)^" + htmlTag)
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)
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const (
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htmlTag = "(?:" + openTag + "|" + closeTag + "|" + htmlComment + "|" +
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processingInstruction + "|" + declaration + "|" + cdata + ")"
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closeTag = "</" + tagName + "\\s*[>]"
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openTag = "<" + tagName + attribute + "*" + "\\s*/?>"
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attribute = "(?:" + "\\s+" + attributeName + attributeValueSpec + "?)"
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attributeValue = "(?:" + unquotedValue + "|" + singleQuotedValue + "|" + doubleQuotedValue + ")"
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attributeValueSpec = "(?:" + "\\s*=" + "\\s*" + attributeValue + ")"
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attributeName = "[a-zA-Z_:][a-zA-Z0-9:._-]*"
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cdata = "<!\\[CDATA\\[[\\s\\S]*?\\]\\]>"
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declaration = "<![A-Z]+" + "\\s+[^>]*>"
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doubleQuotedValue = "\"[^\"]*\""
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htmlComment = "<!---->|<!--(?:-?[^>-])(?:-?[^-])*-->"
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processingInstruction = "[<][?].*?[?][>]"
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singleQuotedValue = "'[^']*'"
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tagName = "[A-Za-z][A-Za-z0-9-]*"
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unquotedValue = "[^\"'=<>`\\x00-\\x20]+"
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)
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// HTMLRendererParameters is a collection of supplementary parameters tweaking
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// the behavior of various parts of HTML renderer.
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type HTMLRendererParameters struct {
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// Prepend this text to each relative URL.
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AbsolutePrefix string
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// Add this text to each footnote anchor, to ensure uniqueness.
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FootnoteAnchorPrefix string
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// Show this text inside the <a> tag for a footnote return link, if the
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// HTML_FOOTNOTE_RETURN_LINKS flag is enabled. If blank, the string
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// <sup>[return]</sup> is used.
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FootnoteReturnLinkContents string
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// If set, add this text to the front of each Heading ID, to ensure
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// uniqueness.
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HeadingIDPrefix string
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// If set, add this text to the back of each Heading ID, to ensure uniqueness.
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HeadingIDSuffix string
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// Increase heading levels: if the offset is 1, <h1> becomes <h2> etc.
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// Negative offset is also valid.
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// Resulting levels are clipped between 1 and 6.
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HeadingLevelOffset int
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Title string // Document title (used if CompletePage is set)
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CSS string // Optional CSS file URL (used if CompletePage is set)
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Icon string // Optional icon file URL (used if CompletePage is set)
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Flags HTMLFlags // Flags allow customizing this renderer's behavior
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}
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// HTMLRenderer 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 NewHTMLRenderer function.
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type HTMLRenderer struct {
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HTMLRendererParameters
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closeTag string // how to end singleton tags: either " />" or ">"
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// Track heading IDs to prevent ID collision in a single generation.
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headingIDs map[string]int
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lastOutputLen int
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disableTags int
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sr *SPRenderer
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}
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const (
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xhtmlClose = " />"
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htmlClose = ">"
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)
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// NewHTMLRenderer creates and configures an HTMLRenderer object, which
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// satisfies the Renderer interface.
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func NewHTMLRenderer(params HTMLRendererParameters) *HTMLRenderer {
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// configure the rendering engine
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closeTag := htmlClose
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if params.Flags&UseXHTML != 0 {
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closeTag = xhtmlClose
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}
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if params.FootnoteReturnLinkContents == "" {
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params.FootnoteReturnLinkContents = `<sup>[return]</sup>`
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}
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return &HTMLRenderer{
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HTMLRendererParameters: params,
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closeTag: closeTag,
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headingIDs: make(map[string]int),
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sr: NewSmartypantsRenderer(params.Flags),
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}
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}
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func isHTMLTag(tag []byte, tagname string) bool {
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found, _ := findHTMLTagPos(tag, tagname)
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return found
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}
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// Look for a character, but ignore it when it's in any kind of quotes, it
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// might be JavaScript
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func skipUntilCharIgnoreQuotes(html []byte, start int, char byte) int {
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inSingleQuote := false
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inDoubleQuote := false
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inGraveQuote := false
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i := start
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for i < len(html) {
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switch {
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case html[i] == char && !inSingleQuote && !inDoubleQuote && !inGraveQuote:
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return i
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case html[i] == '\'':
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inSingleQuote = !inSingleQuote
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case html[i] == '"':
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inDoubleQuote = !inDoubleQuote
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case html[i] == '`':
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inGraveQuote = !inGraveQuote
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}
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i++
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}
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return start
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}
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func findHTMLTagPos(tag []byte, tagname string) (bool, int) {
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i := 0
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if i < len(tag) && tag[0] != '<' {
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return false, -1
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}
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i++
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i = skipSpace(tag, i)
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if i < len(tag) && tag[i] == '/' {
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i++
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}
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i = skipSpace(tag, i)
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j := 0
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for ; i < len(tag); i, j = i+1, j+1 {
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if j >= len(tagname) {
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break
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}
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if strings.ToLower(string(tag[i]))[0] != tagname[j] {
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return false, -1
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}
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}
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if i == len(tag) {
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return false, -1
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}
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rightAngle := skipUntilCharIgnoreQuotes(tag, i, '>')
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if rightAngle >= i {
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return true, rightAngle
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}
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return false, -1
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}
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func skipSpace(tag []byte, i int) int {
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for i < len(tag) && isspace(tag[i]) {
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i++
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}
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return i
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}
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func isRelativeLink(link []byte) (yes bool) {
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// a tag begin with '#'
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if link[0] == '#' {
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return true
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}
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// link begin with '/' but not '//', the second maybe a protocol relative link
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if len(link) >= 2 && link[0] == '/' && link[1] != '/' {
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return true
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}
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// only the root '/'
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if len(link) == 1 && link[0] == '/' {
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return true
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}
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// current directory : begin with "./"
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if bytes.HasPrefix(link, []byte("./")) {
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return true
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}
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// parent directory : begin with "../"
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if bytes.HasPrefix(link, []byte("../")) {
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return true
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}
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return false
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}
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func (r *HTMLRenderer) ensureUniqueHeadingID(id string) string {
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for count, found := r.headingIDs[id]; found; count, found = r.headingIDs[id] {
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tmp := fmt.Sprintf("%s-%d", id, count+1)
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if _, tmpFound := r.headingIDs[tmp]; !tmpFound {
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r.headingIDs[id] = count + 1
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id = tmp
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} else {
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id = id + "-1"
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}
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}
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if _, found := r.headingIDs[id]; !found {
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r.headingIDs[id] = 0
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}
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return id
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}
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func (r *HTMLRenderer) addAbsPrefix(link []byte) []byte {
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if r.AbsolutePrefix != "" && isRelativeLink(link) && link[0] != '.' {
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newDest := r.AbsolutePrefix
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if link[0] != '/' {
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newDest += "/"
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}
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newDest += string(link)
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return []byte(newDest)
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}
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return link
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}
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func appendLinkAttrs(attrs []string, flags HTMLFlags, link []byte) []string {
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if isRelativeLink(link) {
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return attrs
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}
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val := []string{}
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if flags&NofollowLinks != 0 {
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val = append(val, "nofollow")
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}
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if flags&NoreferrerLinks != 0 {
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val = append(val, "noreferrer")
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}
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if flags&NoopenerLinks != 0 {
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val = append(val, "noopener")
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}
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if flags&HrefTargetBlank != 0 {
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attrs = append(attrs, "target=\"_blank\"")
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}
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if len(val) == 0 {
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return attrs
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}
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attr := fmt.Sprintf("rel=%q", strings.Join(val, " "))
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return append(attrs, attr)
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}
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func isMailto(link []byte) bool {
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return bytes.HasPrefix(link, []byte("mailto:"))
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}
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func needSkipLink(flags HTMLFlags, dest []byte) bool {
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if flags&SkipLinks != 0 {
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return true
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}
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return flags&Safelink != 0 && !isSafeLink(dest) && !isMailto(dest)
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}
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func isSmartypantable(node *Node) bool {
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pt := node.Parent.Type
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return pt != Link && pt != CodeBlock && pt != Code
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}
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func appendLanguageAttr(attrs []string, info []byte) []string {
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if len(info) == 0 {
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return attrs
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}
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endOfLang := bytes.IndexAny(info, "\t ")
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if endOfLang < 0 {
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endOfLang = len(info)
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}
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return append(attrs, fmt.Sprintf("class=\"language-%s\"", info[:endOfLang]))
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}
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func (r *HTMLRenderer) tag(w io.Writer, name []byte, attrs []string) {
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w.Write(name)
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if len(attrs) > 0 {
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w.Write(spaceBytes)
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w.Write([]byte(strings.Join(attrs, " ")))
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}
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w.Write(gtBytes)
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r.lastOutputLen = 1
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}
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func footnoteRef(prefix string, node *Node) []byte {
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urlFrag := prefix + string(slugify(node.Destination))
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anchor := fmt.Sprintf(`<a href="#fn:%s">%d</a>`, urlFrag, node.NoteID)
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return []byte(fmt.Sprintf(`<sup class="footnote-ref" id="fnref:%s">%s</sup>`, urlFrag, anchor))
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}
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func footnoteItem(prefix string, slug []byte) []byte {
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return []byte(fmt.Sprintf(`<li id="fn:%s%s">`, prefix, slug))
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}
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func footnoteReturnLink(prefix, returnLink string, slug []byte) []byte {
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const format = ` <a class="footnote-return" href="#fnref:%s%s">%s</a>`
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return []byte(fmt.Sprintf(format, prefix, slug, returnLink))
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}
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func itemOpenCR(node *Node) bool {
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if node.Prev == nil {
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return false
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}
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ld := node.Parent.ListData
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return !ld.Tight && ld.ListFlags&ListTypeDefinition == 0
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}
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func skipParagraphTags(node *Node) bool {
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grandparent := node.Parent.Parent
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if grandparent == nil || grandparent.Type != List {
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return false
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}
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tightOrTerm := grandparent.Tight || node.Parent.ListFlags&ListTypeTerm != 0
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return grandparent.Type == List && tightOrTerm
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}
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func cellAlignment(align CellAlignFlags) string {
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switch align {
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case TableAlignmentLeft:
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return "left"
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case TableAlignmentRight:
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return "right"
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case TableAlignmentCenter:
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return "center"
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default:
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return ""
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}
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}
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func (r *HTMLRenderer) out(w io.Writer, text []byte) {
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if r.disableTags > 0 {
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w.Write(htmlTagRe.ReplaceAll(text, []byte{}))
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|
} else {
|
||
|
|
w.Write(text)
|
||
|
|
}
|
||
|
|
r.lastOutputLen = len(text)
|
||
|
|
}
|
||
|
|
|
||
|
|
func (r *HTMLRenderer) cr(w io.Writer) {
|
||
|
|
if r.lastOutputLen > 0 {
|
||
|
|
r.out(w, nlBytes)
|
||
|
|
}
|
||
|
|
}
|
||
|
|
|
||
|
|
var (
|
||
|
|
nlBytes = []byte{'\n'}
|
||
|
|
gtBytes = []byte{'>'}
|
||
|
|
spaceBytes = []byte{' '}
|
||
|
|
)
|
||
|
|
|
||
|
|
var (
|
||
|
|
brTag = []byte("<br>")
|
||
|
|
brXHTMLTag = []byte("<br />")
|
||
|
|
emTag = []byte("<em>")
|
||
|
|
emCloseTag = []byte("</em>")
|
||
|
|
strongTag = []byte("<strong>")
|
||
|
|
strongCloseTag = []byte("</strong>")
|
||
|
|
delTag = []byte("<del>")
|
||
|
|
delCloseTag = []byte("</del>")
|
||
|
|
ttTag = []byte("<tt>")
|
||
|
|
ttCloseTag = []byte("</tt>")
|
||
|
|
aTag = []byte("<a")
|
||
|
|
aCloseTag = []byte("</a>")
|
||
|
|
preTag = []byte("<pre>")
|
||
|
|
preCloseTag = []byte("</pre>")
|
||
|
|
codeTag = []byte("<code>")
|
||
|
|
codeCloseTag = []byte("</code>")
|
||
|
|
pTag = []byte("<p>")
|
||
|
|
pCloseTag = []byte("</p>")
|
||
|
|
blockquoteTag = []byte("<blockquote>")
|
||
|
|
blockquoteCloseTag = []byte("</blockquote>")
|
||
|
|
hrTag = []byte("<hr>")
|
||
|
|
hrXHTMLTag = []byte("<hr />")
|
||
|
|
ulTag = []byte("<ul>")
|
||
|
|
ulCloseTag = []byte("</ul>")
|
||
|
|
olTag = []byte("<ol>")
|
||
|
|
olCloseTag = []byte("</ol>")
|
||
|
|
dlTag = []byte("<dl>")
|
||
|
|
dlCloseTag = []byte("</dl>")
|
||
|
|
liTag = []byte("<li>")
|
||
|
|
liCloseTag = []byte("</li>")
|
||
|
|
ddTag = []byte("<dd>")
|
||
|
|
ddCloseTag = []byte("</dd>")
|
||
|
|
dtTag = []byte("<dt>")
|
||
|
|
dtCloseTag = []byte("</dt>")
|
||
|
|
tableTag = []byte("<table>")
|
||
|
|
tableCloseTag = []byte("</table>")
|
||
|
|
tdTag = []byte("<td")
|
||
|
|
tdCloseTag = []byte("</td>")
|
||
|
|
thTag = []byte("<th")
|
||
|
|
thCloseTag = []byte("</th>")
|
||
|
|
theadTag = []byte("<thead>")
|
||
|
|
theadCloseTag = []byte("</thead>")
|
||
|
|
tbodyTag = []byte("<tbody>")
|
||
|
|
tbodyCloseTag = []byte("</tbody>")
|
||
|
|
trTag = []byte("<tr>")
|
||
|
|
trCloseTag = []byte("</tr>")
|
||
|
|
h1Tag = []byte("<h1")
|
||
|
|
h1CloseTag = []byte("</h1>")
|
||
|
|
h2Tag = []byte("<h2")
|
||
|
|
h2CloseTag = []byte("</h2>")
|
||
|
|
h3Tag = []byte("<h3")
|
||
|
|
h3CloseTag = []byte("</h3>")
|
||
|
|
h4Tag = []byte("<h4")
|
||
|
|
h4CloseTag = []byte("</h4>")
|
||
|
|
h5Tag = []byte("<h5")
|
||
|
|
h5CloseTag = []byte("</h5>")
|
||
|
|
h6Tag = []byte("<h6")
|
||
|
|
h6CloseTag = []byte("</h6>")
|
||
|
|
|
||
|
|
footnotesDivBytes = []byte("\n<div class=\"footnotes\">\n\n")
|
||
|
|
footnotesCloseDivBytes = []byte("\n</div>\n")
|
||
|
|
)
|
||
|
|
|
||
|
|
func headingTagsFromLevel(level int) ([]byte, []byte) {
|
||
|
|
if level <= 1 {
|
||
|
|
return h1Tag, h1CloseTag
|
||
|
|
}
|
||
|
|
switch level {
|
||
|
|
case 2:
|
||
|
|
return h2Tag, h2CloseTag
|
||
|
|
case 3:
|
||
|
|
return h3Tag, h3CloseTag
|
||
|
|
case 4:
|
||
|
|
return h4Tag, h4CloseTag
|
||
|
|
case 5:
|
||
|
|
return h5Tag, h5CloseTag
|
||
|
|
}
|
||
|
|
return h6Tag, h6CloseTag
|
||
|
|
}
|
||
|
|
|
||
|
|
func (r *HTMLRenderer) outHRTag(w io.Writer) {
|
||
|
|
if r.Flags&UseXHTML == 0 {
|
||
|
|
r.out(w, hrTag)
|
||
|
|
} else {
|
||
|
|
r.out(w, hrXHTMLTag)
|
||
|
|
}
|
||
|
|
}
|
||
|
|
|
||
|
|
// RenderNode is a default renderer of a single node of a syntax tree. For
|
||
|
|
// block nodes it will be called twice: first time with entering=true, second
|
||
|
|
// time with entering=false, so that it could know when it's working on an open
|
||
|
|
// tag and when on close. It writes the result to w.
|
||
|
|
//
|
||
|
|
// The return value is a way to tell the calling walker to adjust its walk
|
||
|
|
// pattern: e.g. it can terminate the traversal by returning Terminate. Or it
|
||
|
|
// can ask the walker to skip a subtree of this node by returning SkipChildren.
|
||
|
|
// The typical behavior is to return GoToNext, which asks for the usual
|
||
|
|
// traversal to the next node.
|
||
|
|
func (r *HTMLRenderer) RenderNode(w io.Writer, node *Node, entering bool) WalkStatus {
|
||
|
|
attrs := []string{}
|
||
|
|
switch node.Type {
|
||
|
|
case Text:
|
||
|
|
if r.Flags&Smartypants != 0 {
|
||
|
|
var tmp bytes.Buffer
|
||
|
|
escapeHTML(&tmp, node.Literal)
|
||
|
|
r.sr.Process(w, tmp.Bytes())
|
||
|
|
} else {
|
||
|
|
if node.Parent.Type == Link {
|
||
|
|
escLink(w, node.Literal)
|
||
|
|
} else {
|
||
|
|
escapeHTML(w, node.Literal)
|
||
|
|
}
|
||
|
|
}
|
||
|
|
case Softbreak:
|
||
|
|
r.cr(w)
|
||
|
|
// TODO: make it configurable via out(renderer.softbreak)
|
||
|
|
case Hardbreak:
|
||
|
|
if r.Flags&UseXHTML == 0 {
|
||
|
|
r.out(w, brTag)
|
||
|
|
} else {
|
||
|
|
r.out(w, brXHTMLTag)
|
||
|
|
}
|
||
|
|
r.cr(w)
|
||
|
|
case Emph:
|
||
|
|
if entering {
|
||
|
|
r.out(w, emTag)
|
||
|
|
} else {
|
||
|
|
r.out(w, emCloseTag)
|
||
|
|
}
|
||
|
|
case Strong:
|
||
|
|
if entering {
|
||
|
|
r.out(w, strongTag)
|
||
|
|
} else {
|
||
|
|
r.out(w, strongCloseTag)
|
||
|
|
}
|
||
|
|
case Del:
|
||
|
|
if entering {
|
||
|
|
r.out(w, delTag)
|
||
|
|
} else {
|
||
|
|
r.out(w, delCloseTag)
|
||
|
|
}
|
||
|
|
case HTMLSpan:
|
||
|
|
if r.Flags&SkipHTML != 0 {
|
||
|
|
break
|
||
|
|
}
|
||
|
|
r.out(w, node.Literal)
|
||
|
|
case Link:
|
||
|
|
// mark it but don't link it if it is not a safe link: no smartypants
|
||
|
|
dest := node.LinkData.Destination
|
||
|
|
if needSkipLink(r.Flags, dest) {
|
||
|
|
if entering {
|
||
|
|
r.out(w, ttTag)
|
||
|
|
} else {
|
||
|
|
r.out(w, ttCloseTag)
|
||
|
|
}
|
||
|
|
} else {
|
||
|
|
if entering {
|
||
|
|
dest = r.addAbsPrefix(dest)
|
||
|
|
var hrefBuf bytes.Buffer
|
||
|
|
hrefBuf.WriteString("href=\"")
|
||
|
|
escLink(&hrefBuf, dest)
|
||
|
|
hrefBuf.WriteByte('"')
|
||
|
|
attrs = append(attrs, hrefBuf.String())
|
||
|
|
if node.NoteID != 0 {
|
||
|
|
r.out(w, footnoteRef(r.FootnoteAnchorPrefix, node))
|
||
|
|
break
|
||
|
|
}
|
||
|
|
attrs = appendLinkAttrs(attrs, r.Flags, dest)
|
||
|
|
if len(node.LinkData.Title) > 0 {
|
||
|
|
var titleBuff bytes.Buffer
|
||
|
|
titleBuff.WriteString("title=\"")
|
||
|
|
escapeHTML(&titleBuff, node.LinkData.Title)
|
||
|
|
titleBuff.WriteByte('"')
|
||
|
|
attrs = append(attrs, titleBuff.String())
|
||
|
|
}
|
||
|
|
r.tag(w, aTag, attrs)
|
||
|
|
} else {
|
||
|
|
if node.NoteID != 0 {
|
||
|
|
break
|
||
|
|
}
|
||
|
|
r.out(w, aCloseTag)
|
||
|
|
}
|
||
|
|
}
|
||
|
|
case Image:
|
||
|
|
if r.Flags&SkipImages != 0 {
|
||
|
|
return SkipChildren
|
||
|
|
}
|
||
|
|
if entering {
|
||
|
|
dest := node.LinkData.Destination
|
||
|
|
dest = r.addAbsPrefix(dest)
|
||
|
|
if r.disableTags == 0 {
|
||
|
|
//if options.safe && potentiallyUnsafe(dest) {
|
||
|
|
//out(w, `<img src="" alt="`)
|
||
|
|
//} else {
|
||
|
|
r.out(w, []byte(`<img src="`))
|
||
|
|
escLink(w, dest)
|
||
|
|
r.out(w, []byte(`" alt="`))
|
||
|
|
//}
|
||
|
|
}
|
||
|
|
r.disableTags++
|
||
|
|
} else {
|
||
|
|
r.disableTags--
|
||
|
|
if r.disableTags == 0 {
|
||
|
|
if node.LinkData.Title != nil {
|
||
|
|
r.out(w, []byte(`" title="`))
|
||
|
|
escapeHTML(w, node.LinkData.Title)
|
||
|
|
}
|
||
|
|
r.out(w, []byte(`" />`))
|
||
|
|
}
|
||
|
|
}
|
||
|
|
case Code:
|
||
|
|
r.out(w, codeTag)
|
||
|
|
escapeHTML(w, node.Literal)
|
||
|
|
r.out(w, codeCloseTag)
|
||
|
|
case Document:
|
||
|
|
break
|
||
|
|
case Paragraph:
|
||
|
|
if skipParagraphTags(node) {
|
||
|
|
break
|
||
|
|
}
|
||
|
|
if entering {
|
||
|
|
// TODO: untangle this clusterfuck about when the newlines need
|
||
|
|
// to be added and when not.
|
||
|
|
if node.Prev != nil {
|
||
|
|
switch node.Prev.Type {
|
||
|
|
case HTMLBlock, List, Paragraph, Heading, CodeBlock, BlockQuote, HorizontalRule:
|
||
|
|
r.cr(w)
|
||
|
|
}
|
||
|
|
}
|
||
|
|
if node.Parent.Type == BlockQuote && node.Prev == nil {
|
||
|
|
r.cr(w)
|
||
|
|
}
|
||
|
|
r.out(w, pTag)
|
||
|
|
} else {
|
||
|
|
r.out(w, pCloseTag)
|
||
|
|
if !(node.Parent.Type == Item && node.Next == nil) {
|
||
|
|
r.cr(w)
|
||
|
|
}
|
||
|
|
}
|
||
|
|
case BlockQuote:
|
||
|
|
if entering {
|
||
|
|
r.cr(w)
|
||
|
|
r.out(w, blockquoteTag)
|
||
|
|
} else {
|
||
|
|
r.out(w, blockquoteCloseTag)
|
||
|
|
r.cr(w)
|
||
|
|
}
|
||
|
|
case HTMLBlock:
|
||
|
|
if r.Flags&SkipHTML != 0 {
|
||
|
|
break
|
||
|
|
}
|
||
|
|
r.cr(w)
|
||
|
|
r.out(w, node.Literal)
|
||
|
|
r.cr(w)
|
||
|
|
case Heading:
|
||
|
|
headingLevel := r.HTMLRendererParameters.HeadingLevelOffset + node.Level
|
||
|
|
openTag, closeTag := headingTagsFromLevel(headingLevel)
|
||
|
|
if entering {
|
||
|
|
if node.IsTitleblock {
|
||
|
|
attrs = append(attrs, `class="title"`)
|
||
|
|
}
|
||
|
|
if node.HeadingID != "" {
|
||
|
|
id := r.ensureUniqueHeadingID(node.HeadingID)
|
||
|
|
if r.HeadingIDPrefix != "" {
|
||
|
|
id = r.HeadingIDPrefix + id
|
||
|
|
}
|
||
|
|
if r.HeadingIDSuffix != "" {
|
||
|
|
id = id + r.HeadingIDSuffix
|
||
|
|
}
|
||
|
|
attrs = append(attrs, fmt.Sprintf(`id="%s"`, id))
|
||
|
|
}
|
||
|
|
r.cr(w)
|
||
|
|
r.tag(w, openTag, attrs)
|
||
|
|
} else {
|
||
|
|
r.out(w, closeTag)
|
||
|
|
if !(node.Parent.Type == Item && node.Next == nil) {
|
||
|
|
r.cr(w)
|
||
|
|
}
|
||
|
|
}
|
||
|
|
case HorizontalRule:
|
||
|
|
r.cr(w)
|
||
|
|
r.outHRTag(w)
|
||
|
|
r.cr(w)
|
||
|
|
case List:
|
||
|
|
openTag := ulTag
|
||
|
|
closeTag := ulCloseTag
|
||
|
|
if node.ListFlags&ListTypeOrdered != 0 {
|
||
|
|
openTag = olTag
|
||
|
|
closeTag = olCloseTag
|
||
|
|
}
|
||
|
|
if node.ListFlags&ListTypeDefinition != 0 {
|
||
|
|
openTag = dlTag
|
||
|
|
closeTag = dlCloseTag
|
||
|
|
}
|
||
|
|
if entering {
|
||
|
|
if node.IsFootnotesList {
|
||
|
|
r.out(w, footnotesDivBytes)
|
||
|
|
r.outHRTag(w)
|
||
|
|
r.cr(w)
|
||
|
|
}
|
||
|
|
r.cr(w)
|
||
|
|
if node.Parent.Type == Item && node.Parent.Parent.Tight {
|
||
|
|
r.cr(w)
|
||
|
|
}
|
||
|
|
r.tag(w, openTag[:len(openTag)-1], attrs)
|
||
|
|
r.cr(w)
|
||
|
|
} else {
|
||
|
|
r.out(w, closeTag)
|
||
|
|
//cr(w)
|
||
|
|
//if node.parent.Type != Item {
|
||
|
|
// cr(w)
|
||
|
|
//}
|
||
|
|
if node.Parent.Type == Item && node.Next != nil {
|
||
|
|
r.cr(w)
|
||
|
|
}
|
||
|
|
if node.Parent.Type == Document || node.Parent.Type == BlockQuote {
|
||
|
|
r.cr(w)
|
||
|
|
}
|
||
|
|
if node.IsFootnotesList {
|
||
|
|
r.out(w, footnotesCloseDivBytes)
|
||
|
|
}
|
||
|
|
}
|
||
|
|
case Item:
|
||
|
|
openTag := liTag
|
||
|
|
closeTag := liCloseTag
|
||
|
|
if node.ListFlags&ListTypeDefinition != 0 {
|
||
|
|
openTag = ddTag
|
||
|
|
closeTag = ddCloseTag
|
||
|
|
}
|
||
|
|
if node.ListFlags&ListTypeTerm != 0 {
|
||
|
|
openTag = dtTag
|
||
|
|
closeTag = dtCloseTag
|
||
|
|
}
|
||
|
|
if entering {
|
||
|
|
if itemOpenCR(node) {
|
||
|
|
r.cr(w)
|
||
|
|
}
|
||
|
|
if node.ListData.RefLink != nil {
|
||
|
|
slug := slugify(node.ListData.RefLink)
|
||
|
|
r.out(w, footnoteItem(r.FootnoteAnchorPrefix, slug))
|
||
|
|
break
|
||
|
|
}
|
||
|
|
r.out(w, openTag)
|
||
|
|
} else {
|
||
|
|
if node.ListData.RefLink != nil {
|
||
|
|
slug := slugify(node.ListData.RefLink)
|
||
|
|
if r.Flags&FootnoteReturnLinks != 0 {
|
||
|
|
r.out(w, footnoteReturnLink(r.FootnoteAnchorPrefix, r.FootnoteReturnLinkContents, slug))
|
||
|
|
}
|
||
|
|
}
|
||
|
|
r.out(w, closeTag)
|
||
|
|
r.cr(w)
|
||
|
|
}
|
||
|
|
case CodeBlock:
|
||
|
|
attrs = appendLanguageAttr(attrs, node.Info)
|
||
|
|
r.cr(w)
|
||
|
|
r.out(w, preTag)
|
||
|
|
r.tag(w, codeTag[:len(codeTag)-1], attrs)
|
||
|
|
escapeHTML(w, node.Literal)
|
||
|
|
r.out(w, codeCloseTag)
|
||
|
|
r.out(w, preCloseTag)
|
||
|
|
if node.Parent.Type != Item {
|
||
|
|
r.cr(w)
|
||
|
|
}
|
||
|
|
case Table:
|
||
|
|
if entering {
|
||
|
|
r.cr(w)
|
||
|
|
r.out(w, tableTag)
|
||
|
|
} else {
|
||
|
|
r.out(w, tableCloseTag)
|
||
|
|
r.cr(w)
|
||
|
|
}
|
||
|
|
case TableCell:
|
||
|
|
openTag := tdTag
|
||
|
|
closeTag := tdCloseTag
|
||
|
|
if node.IsHeader {
|
||
|
|
openTag = thTag
|
||
|
|
closeTag = thCloseTag
|
||
|
|
}
|
||
|
|
if entering {
|
||
|
|
align := cellAlignment(node.Align)
|
||
|
|
if align != "" {
|
||
|
|
attrs = append(attrs, fmt.Sprintf(`align="%s"`, align))
|
||
|
|
}
|
||
|
|
if node.Prev == nil {
|
||
|
|
r.cr(w)
|
||
|
|
}
|
||
|
|
r.tag(w, openTag, attrs)
|
||
|
|
} else {
|
||
|
|
r.out(w, closeTag)
|
||
|
|
r.cr(w)
|
||
|
|
}
|
||
|
|
case TableHead:
|
||
|
|
if entering {
|
||
|
|
r.cr(w)
|
||
|
|
r.out(w, theadTag)
|
||
|
|
} else {
|
||
|
|
r.out(w, theadCloseTag)
|
||
|
|
r.cr(w)
|
||
|
|
}
|
||
|
|
case TableBody:
|
||
|
|
if entering {
|
||
|
|
r.cr(w)
|
||
|
|
r.out(w, tbodyTag)
|
||
|
|
// XXX: this is to adhere to a rather silly test. Should fix test.
|
||
|
|
if node.FirstChild == nil {
|
||
|
|
r.cr(w)
|
||
|
|
}
|
||
|
|
} else {
|
||
|
|
r.out(w, tbodyCloseTag)
|
||
|
|
r.cr(w)
|
||
|
|
}
|
||
|
|
case TableRow:
|
||
|
|
if entering {
|
||
|
|
r.cr(w)
|
||
|
|
r.out(w, trTag)
|
||
|
|
} else {
|
||
|
|
r.out(w, trCloseTag)
|
||
|
|
r.cr(w)
|
||
|
|
}
|
||
|
|
default:
|
||
|
|
panic("Unknown node type " + node.Type.String())
|
||
|
|
}
|
||
|
|
return GoToNext
|
||
|
|
}
|
||
|
|
|
||
|
|
// RenderHeader writes HTML document preamble and TOC if requested.
|
||
|
|
func (r *HTMLRenderer) RenderHeader(w io.Writer, ast *Node) {
|
||
|
|
r.writeDocumentHeader(w)
|
||
|
|
if r.Flags&TOC != 0 {
|
||
|
|
r.writeTOC(w, ast)
|
||
|
|
}
|
||
|
|
}
|
||
|
|
|
||
|
|
// RenderFooter writes HTML document footer.
|
||
|
|
func (r *HTMLRenderer) RenderFooter(w io.Writer, ast *Node) {
|
||
|
|
if r.Flags&CompletePage == 0 {
|
||
|
|
return
|
||
|
|
}
|
||
|
|
io.WriteString(w, "\n</body>\n</html>\n")
|
||
|
|
}
|
||
|
|
|
||
|
|
func (r *HTMLRenderer) writeDocumentHeader(w io.Writer) {
|
||
|
|
if r.Flags&CompletePage == 0 {
|
||
|
|
return
|
||
|
|
}
|
||
|
|
ending := ""
|
||
|
|
if r.Flags&UseXHTML != 0 {
|
||
|
|
io.WriteString(w, "<!DOCTYPE html PUBLIC \"-//W3C//DTD XHTML 1.0 Transitional//EN\" ")
|
||
|
|
io.WriteString(w, "\"http://www.w3.org/TR/xhtml1/DTD/xhtml1-transitional.dtd\">\n")
|
||
|
|
io.WriteString(w, "<html xmlns=\"http://www.w3.org/1999/xhtml\">\n")
|
||
|
|
ending = " /"
|
||
|
|
} else {
|
||
|
|
io.WriteString(w, "<!DOCTYPE html>\n")
|
||
|
|
io.WriteString(w, "<html>\n")
|
||
|
|
}
|
||
|
|
io.WriteString(w, "<head>\n")
|
||
|
|
io.WriteString(w, " <title>")
|
||
|
|
if r.Flags&Smartypants != 0 {
|
||
|
|
r.sr.Process(w, []byte(r.Title))
|
||
|
|
} else {
|
||
|
|
escapeHTML(w, []byte(r.Title))
|
||
|
|
}
|
||
|
|
io.WriteString(w, "</title>\n")
|
||
|
|
io.WriteString(w, " <meta name=\"GENERATOR\" content=\"Blackfriday Markdown Processor v")
|
||
|
|
io.WriteString(w, Version)
|
||
|
|
io.WriteString(w, "\"")
|
||
|
|
io.WriteString(w, ending)
|
||
|
|
io.WriteString(w, ">\n")
|
||
|
|
io.WriteString(w, " <meta charset=\"utf-8\"")
|
||
|
|
io.WriteString(w, ending)
|
||
|
|
io.WriteString(w, ">\n")
|
||
|
|
if r.CSS != "" {
|
||
|
|
io.WriteString(w, " <link rel=\"stylesheet\" type=\"text/css\" href=\"")
|
||
|
|
escapeHTML(w, []byte(r.CSS))
|
||
|
|
io.WriteString(w, "\"")
|
||
|
|
io.WriteString(w, ending)
|
||
|
|
io.WriteString(w, ">\n")
|
||
|
|
}
|
||
|
|
if r.Icon != "" {
|
||
|
|
io.WriteString(w, " <link rel=\"icon\" type=\"image/x-icon\" href=\"")
|
||
|
|
escapeHTML(w, []byte(r.Icon))
|
||
|
|
io.WriteString(w, "\"")
|
||
|
|
io.WriteString(w, ending)
|
||
|
|
io.WriteString(w, ">\n")
|
||
|
|
}
|
||
|
|
io.WriteString(w, "</head>\n")
|
||
|
|
io.WriteString(w, "<body>\n\n")
|
||
|
|
}
|
||
|
|
|
||
|
|
func (r *HTMLRenderer) writeTOC(w io.Writer, ast *Node) {
|
||
|
|
buf := bytes.Buffer{}
|
||
|
|
|
||
|
|
inHeading := false
|
||
|
|
tocLevel := 0
|
||
|
|
headingCount := 0
|
||
|
|
|
||
|
|
ast.Walk(func(node *Node, entering bool) WalkStatus {
|
||
|
|
if node.Type == Heading && !node.HeadingData.IsTitleblock {
|
||
|
|
inHeading = entering
|
||
|
|
if entering {
|
||
|
|
node.HeadingID = fmt.Sprintf("toc_%d", headingCount)
|
||
|
|
if node.Level == tocLevel {
|
||
|
|
buf.WriteString("</li>\n\n<li>")
|
||
|
|
} else if node.Level < tocLevel {
|
||
|
|
for node.Level < tocLevel {
|
||
|
|
tocLevel--
|
||
|
|
buf.WriteString("</li>\n</ul>")
|
||
|
|
}
|
||
|
|
buf.WriteString("</li>\n\n<li>")
|
||
|
|
} else {
|
||
|
|
for node.Level > tocLevel {
|
||
|
|
tocLevel++
|
||
|
|
buf.WriteString("\n<ul>\n<li>")
|
||
|
|
}
|
||
|
|
}
|
||
|
|
|
||
|
|
fmt.Fprintf(&buf, `<a href="#toc_%d">`, headingCount)
|
||
|
|
headingCount++
|
||
|
|
} else {
|
||
|
|
buf.WriteString("</a>")
|
||
|
|
}
|
||
|
|
return GoToNext
|
||
|
|
}
|
||
|
|
|
||
|
|
if inHeading {
|
||
|
|
return r.RenderNode(&buf, node, entering)
|
||
|
|
}
|
||
|
|
|
||
|
|
return GoToNext
|
||
|
|
})
|
||
|
|
|
||
|
|
for ; tocLevel > 0; tocLevel-- {
|
||
|
|
buf.WriteString("</li>\n</ul>")
|
||
|
|
}
|
||
|
|
|
||
|
|
if buf.Len() > 0 {
|
||
|
|
io.WriteString(w, "<nav>\n")
|
||
|
|
w.Write(buf.Bytes())
|
||
|
|
io.WriteString(w, "\n\n</nav>\n")
|
||
|
|
}
|
||
|
|
r.lastOutputLen = buf.Len()
|
||
|
|
}
|