style(markdown): fix typo in package name

1 files changed, 179 insertions, 0 deletions

diff --git a/markdown/ast_external.go b/markdown/ast_external.go
new file mode 100644
index 0000000..a172b2b
--- /dev/null
+++ b/markdown/ast_external.go
@@ -0,0 +1,179 @@
+package markdown
+
+import (
+	"fmt"
+	"html/template"
+)
+
+type astLink struct {
+	content block
+	href    block
+}
+
+func (a *astLink) Eval() (template.HTML, *ParseError) {
+	content, err := a.content.Eval()
+	if err != nil {
+		return "", err
+	}
+	href, err := a.href.Eval()
+	if err != nil {
+		return "", err
+	}
+	return template.HTML(fmt.Sprintf(`<a href="%s">%s</a>`, href, content)), nil
+}
+
+type astImage struct {
+	alt    block
+	src    block
+	source []*astParagraph
+}
+
+func (a *astImage) Eval() (template.HTML, *ParseError) {
+	alt, err := a.alt.Eval()
+	if err != nil {
+		return "", err
+	}
+	src, err := a.src.Eval()
+	if err != nil {
+		return "", err
+	}
+	if a.source == nil {
+		return template.HTML(fmt.Sprintf(`<figure><img alt="%s" src="%s"></figure>`, alt, src)), nil
+	}
+	var s template.HTML
+	for _, c := range a.source {
+		ct, err := c.Eval()
+		if err != nil {
+			return "", err
+		}
+		s += ct + " "
+	}
+	s = s[:len(s)-1]
+	return template.HTML(fmt.Sprintf(`<figure><img alt="%s" src="%s"><figcaption>%s</figcaption></figure>`, alt, src, s)), nil
+}
+
+func external(lxs *lexers) (block, *ParseError) {
+	tp := lxs.Current().Value
+	if !lxs.Next() {
+		return astLiteral(tp), nil
+	}
+	lxs.Before() // because we call Next
+	var b block
+	var err *ParseError
+	switch tp {
+	case "![":
+		b, err = image(lxs)
+	case "[":
+		b, err = link(lxs)
+	default:
+		b = astLiteral(tp)
+	}
+	return b, err
+}
+
+func link(lxs *lexers) (block, *ParseError) {
+	lk := new(astLink)
+	start := lxs.current
+	content, href, _, ok := parseExternal(lxs, false)
+	if !ok {
+		return reset(lxs, start), nil
+	}
+	lk.content = astLiteral(content)
+	lk.href = astLiteral(href)
+	return lk, nil
+}
+
+func image(lxs *lexers) (block, *ParseError) {
+	img := new(astImage)
+	start := lxs.current
+	alt, src, source, ok := parseExternal(lxs, true)
+	if !ok {
+		return reset(lxs, start), nil
+	}
+	img.alt = astLiteral(alt)
+	img.src = astLiteral(src)
+	img.source = source
+	return img, nil
+}
+
+func parseExternal(lxs *lexers, withSource bool) (string, string, []*astParagraph, bool) {
+	next := false
+	var s string
+	var first string
+	var end string
+	var ps []*astParagraph
+	n := 0
+	fn := func() bool {
+		p, err := paragraph(lxs, true)
+		if err != nil {
+			return false
+		}
+		ps = append(ps, p)
+		n = 0
+		return true
+	}
+	for lxs.Next() && n < 2 {
+		switch lxs.Current().Type {
+		case lexerBreak:
+			if !withSource {
+				return "", "", nil, false
+			}
+			n += len(lxs.Current().Value)
+			if first != "" && end != "" {
+				if !lxs.Next() {
+					return first, end, ps, true
+				}
+				ok := fn()
+				if !ok {
+					return "", "", nil, false
+				}
+				lxs.Before() // because we must parse lexerBreak
+			}
+		case lexerExternal:
+			if first != "" && end != "" {
+				return "", "", nil, false
+			}
+			if n > 0 && (first == "" || end == "") {
+				return "", "", nil, false
+			}
+			n = 0
+			if !next {
+				if lxs.Current().Value != "](" || !lxs.Next() {
+					return "", "", nil, false
+				}
+				lxs.Before() // because we called Next
+				first = s
+				s = ""
+				next = true
+			} else {
+				if lxs.Current().Value != ")" {
+					return "", "", nil, false
+				}
+				if !withSource {
+					return first, s, nil, true
+				}
+				end = s
+				s = ""
+				if lxs.Next() && lxs.Current().Type != lexerBreak {
+					return "", "", nil, false
+				}
+				lxs.Before() // because we called Next
+			}
+		default:
+			if ps != nil {
+				return "", "", nil, false
+			}
+			n = 0
+			s += lxs.Current().Value
+		}
+	}
+	if !withSource {
+		return "", "", nil, false
+	}
+	return first, end, ps, true
+}
+
+func reset(lxs *lexers, start int) block {
+	lxs.current = start
+	return astLiteral(lxs.Current().Value)
+}