feat(markdown): support list

1 files changed, 77 insertions, 0 deletions

diff --git a/mardown/ast_list.go b/mardown/ast_list.go
new file mode 100644
index 0000000..39be70c
--- /dev/null
+++ b/mardown/ast_list.go
@@ -0,0 +1,77 @@
+package mardown
+
+import (
+	"fmt"
+	"html/template"
+	"regexp"
+)
+
+var regexOrdered = regexp.MustCompile(`\d+\.`)
+
+type listType string
+
+const (
+	listUnordered listType = "ul"
+	listOrdered   listType = "ol"
+)
+
+type astList struct {
+	tag     listType
+	content []*astParagraph
+}
+
+func (a *astList) Eval() (template.HTML, error) {
+	var content template.HTML
+	for _, c := range a.content {
+		ct, err := c.Eval()
+		if err != nil {
+			return "", err
+		}
+		content += template.HTML(fmt.Sprintf("<li>%s</li>", trimSpace(ct)))
+	}
+	return template.HTML(fmt.Sprintf("<%s>%s</%s>", a.tag, content, a.tag)), nil
+}
+
+func list(lxs *lexers) (block, error) {
+	tree := new(astList)
+	current := lxs.Current().Value
+	tree.tag = detectListType(current)
+	if len(tree.tag) == 0 {
+		return paragraph(lxs, false)
+	}
+	n := 0
+	for lxs.Next() && n < 2 {
+		switch lxs.Current().Type {
+		case lexerBreak:
+			n++
+		case lexerList:
+			n = 0
+			tp := detectListType(lxs.Current().Value)
+			if tp != tree.tag {
+				lxs.Before() // because we dit not use it
+				return tree, nil
+			}
+		default:
+			n = 0
+			c, err := paragraph(lxs, true)
+			if err != nil {
+				return nil, err
+			}
+			tree.content = append(tree.content, c)
+		}
+	}
+	return tree, nil
+}
+
+func detectListType(val string) listType {
+	if []rune(val)[0] == '-' {
+		if len(val) > 1 {
+			return ""
+		}
+		return listUnordered
+	}
+	if !regexOrdered.MatchString(val) {
+		return ""
+	}
+	return listOrdered
+}