parse out isbn from refs

1 files changed, 37 insertions, 34 deletions

diff --git a/skate/schema.go b/skate/schema.go
index 6c96bb8..6f872eb 100644
--- a/skate/schema.go
+++ b/skate/schema.go
@@ -47,45 +47,48 @@ func RefToRelease(ref *Ref) (*Release, error) {
 		contribs[i].RawName = name
 	}
 	release.Contribs = contribs
-	// XXX: Find ISBN in unstructured. Might be expensive, do we need a flag?
-	unlo := strings.ToLower(ref.Biblio.Unstructured)
-	if strings.Contains(unlo, "isbn") {
-		// ISBN: 10: 0137822693, pp: 373
-		// Robotec, E. (1996). Scorbot ER VII, User's Manual, Eshed Robotec,
-		// ISBN9652910333. Shannon, C. (1948). A Mathematical Theory of
-		// Communication. The Bell System Technical Journal. July; October,
-		// Vol. 27, pp. 379-423; 623-656.
-		// Artech House, ISBN: 978-1-60807-201-9, 2011.
-		// ...
-		var (
-			candidates10 = isbn10Regex.FindAllString(ref.Biblio.Unstructured, -1)
-			candidates13 = isbn13Regex.FindAllString(ref.Biblio.Unstructured, -1)
-			valid        = set.New()
-		)
-		for _, v := range append(candidates10, candidates13...) {
-			var u []rune
-			for _, c := range v {
-				if c >= '0' && c <= '9' || c == 'x' || c == 'X' {
-					u = append(u, c)
-				}
+	if strings.Contains(strings.ToLower(ref.Biblio.Unstructured), "isbn") {
+		release.ExtIDs.ISBN = parseIsbn(ref.Biblio.Unstructured)
+	}
+	return &release, nil
+}
+
+// parseIsbn tries to find and validate ISBN from unstrucuted data.
+func parseIsbn(s string) []string {
+	// ISBN: 10: 0137822693, pp: 373
+	// Robotec, E. (1996). Scorbot ER VII, User's Manual, Eshed Robotec,
+	// ISBN9652910333. Shannon, C. (1948). A Mathematical Theory of
+	// Communication. The Bell System Technical Journal. July; October,
+	// Vol. 27, pp. 379-423; 623-656.
+	// Artech House, ISBN: 978-1-60807-201-9, 2011.
+	// ...
+	var (
+		candidates10 = isbn10Regex.FindAllString(s, -1)
+		candidates13 = isbn13Regex.FindAllString(s, -1)
+		valid        = set.New()
+	)
+	for _, v := range append(candidates10, candidates13...) {
+		var u []rune
+		for _, c := range v {
+			if c >= '0' && c <= '9' || c == 'x' || c == 'X' {
+				u = append(u, c)
 			}
-			s := string(u)
-			if !isbn.Validate(s) {
+		}
+		s := string(u)
+		if !isbn.Validate(s) {
+			continue
+		}
+		if len(s) < 12 {
+			w, err := isbn.To13(s)
+			if err != nil {
 				continue
 			}
-			if len(s) < 12 {
-				w, err := isbn.To13(s)
-				if err != nil {
-					continue
-				}
-				valid.Add(w)
-			} else {
-				valid.Add(s)
-			}
+			valid.Add(w)
+		} else {
+			valid.Add(s)
 		}
-		release.ExtIDs.ISBN = valid.Slice()
 	}
-	return &release, nil
+	return valid.Slice()
 }
 
 // Ref is a reference document, can be very partial.