Function link

inline.go:232–588

'[': parse a link or an image or a footnote

(p *Markdown, data []byte, offset int)

// '[': parse a link or an image or a footnote
func link(p *Markdown, data []byte, offset int) (int, *Node) {
	// no links allowed inside regular links, footnote, and deferred footnotes
	if p.insideLink && (offset > 0 && data[offset-1] == '[' || len(data)-1 > offset && data[offset+1] == '^') {
		return 0, nil
	}

	var t linkType
	switch {
	// special case: ![^text] == deferred footnote (that follows something with
	// an exclamation point)
	case p.extensions&Footnotes != 0 && len(data)-1 > offset && data[offset+1] == '^':
		t = linkDeferredFootnote
	// ![alt] == image
	case offset >= 0 && data[offset] == '!':
		t = linkImg
		offset++
	// ^[text] == inline footnote
	// [^refId] == deferred footnote
	case p.extensions&Footnotes != 0:
		if offset >= 0 && data[offset] == '^' {
			t = linkInlineFootnote
			offset++
		} else if len(data)-1 > offset && data[offset+1] == '^' {
			t = linkDeferredFootnote
		}
	// [text] == regular link
	default:
		t = linkNormal
	}

	data = data[offset:]

	var (
		i                       = 1
		noteID                  int
		title, link, altContent []byte
		textHasNl               = false
	)

	if t == linkDeferredFootnote {
		i++
	}

	// look for the matching closing bracket
	for level := 1; level > 0 && i < len(data); i++ {
		switch {
		case data[i] == '\n':
			textHasNl = true

		case isBackslashEscaped(data, i):
			continue

		case data[i] == '[':
			level++

		case data[i] == ']':
			level--
			if level <= 0 {