Restructure directory layout: org subpackage

org/headline.go

@@ -0,0 +1,69 @@
+package org
+
+import (
+	"regexp"
+	"strings"
+	"unicode"
+)
+
+type Headline struct {
+	Lvl      int
+	Status   string
+	Priority string
+	Title    []Node
+	Tags     []string
+	Children []Node
+}
+
+var headlineRegexp = regexp.MustCompile(`^([*]+)\s+(.*)`)
+var tagRegexp = regexp.MustCompile(`(.*?)\s*(:[A-Za-z0-9@#%:]+:\s*$)`)
+
+func lexHeadline(line string) (token, bool) {
+	if m := headlineRegexp.FindStringSubmatch(line); m != nil {
+		return token{"headline", 0, m[2], m}, true
+	}
+	return nilToken, false
+}
+
+func (d *Document) todoKeywords() []string {
+	return strings.FieldsFunc(d.Get("TODO"), func(r rune) bool {
+		return unicode.IsSpace(r) || r == '|'
+	})
+}
+
+func (d *Document) parseHeadline(i int, parentStop stopFn) (int, Node) {
+	t, headline := d.tokens[i], Headline{}
+	headline.Lvl = len(t.matches[1])
+	text := t.content
+
+	for _, k := range d.todoKeywords() {
+		if strings.HasPrefix(text, k) && len(text) > len(k) && unicode.IsSpace(rune(text[len(k)])) {
+			headline.Status = k
+			text = text[len(k)+1:]
+			break
+		}
+	}
+
+	if len(text) >= 3 && text[0:2] == "[#" && strings.Contains("ABC", text[2:3]) && text[3] == ']' {
+		headline.Priority = text[2:3]
+		text = strings.TrimSpace(text[4:])
+	}
+
+	if m := tagRegexp.FindStringSubmatch(text); m != nil {
+		text = m[1]
+		headline.Tags = strings.FieldsFunc(m[2], func(r rune) bool { return r == ':' })
+	}
+
+	headline.Title = d.parseInline(text)
+
+	stop := func(d *Document, i int) bool {
+		return parentStop(d, i) || d.tokens[i].kind == "headline" && d.tokens[i].lvl <= headline.Lvl
+	}
+	consumed, nodes := d.parseMany(i+1, stop)
+	headline.Children = nodes
+
+	if headline.Lvl == 1 && text == d.Footnotes.Title && d.Footnotes.ExcludeHeading {
+		return consumed + 1, nil
+	}
+	return consumed + 1, headline
+}