initial Go port of streamrip

internal/naming/naming.go

@@ -0,0 +1,74 @@
+package naming
+
+import (
+	"fmt"
+	"regexp"
+	"strconv"
+	"strings"
+	"unicode"
+)
+
+type Config struct {
+	RestrictCharacters bool
+	TruncateTo         int
+}
+
+var tokenRe = regexp.MustCompile(`\{([a-z_]+)(?::0?(\d+))?\}`)
+var invalidPathRe = regexp.MustCompile(`[<>:"/\\|?*\x00-\x1F]`)
+
+func FormatTemplate(template string, values map[string]string) string {
+	return tokenRe.ReplaceAllStringFunc(template, func(m string) string {
+		groups := tokenRe.FindStringSubmatch(m)
+		if len(groups) < 2 {
+			return m
+		}
+		key := groups[1]
+		val := values[key]
+		if len(groups) >= 3 && groups[2] != "" {
+			if n, err := strconv.Atoi(val); err == nil {
+				if width, widthErr := strconv.Atoi(groups[2]); widthErr == nil {
+					return fmt.Sprintf("%0*d", width, n)
+				}
+			}
+		}
+		return val
+	})
+}
+
+func CleanName(in string, cfg Config) string {
+	s := strings.TrimSpace(in)
+	s = invalidPathRe.ReplaceAllString(s, "_")
+	if cfg.RestrictCharacters {
+		r := make([]rune, 0, len(s))
+		for _, ch := range s {
+			if ch >= 32 && ch <= 126 {
+				r = append(r, ch)
+			}
+		}
+		s = string(r)
+	}
+	if cfg.TruncateTo > 0 {
+		runes := []rune(s)
+		if len(runes) > cfg.TruncateTo {
+			s = string(runes[:cfg.TruncateTo])
+		}
+	}
+	s = strings.TrimSpace(s)
+	if s == "" {
+		return "Unknown"
+	}
+	return s
+}
+
+func YearFromDate(date string) string {
+	if len(date) >= 4 {
+		prefix := date[:4]
+		for _, ch := range prefix {
+			if !unicode.IsDigit(ch) {
+				return "Unknown"
+			}
+		}
+		return prefix
+	}
+	return "Unknown"
+}

internal/naming/naming_test.go

@@ -0,0 +1,22 @@
+package naming
+
+import "testing"
+
+func TestFormatTemplate(t *testing.T) {
+	got := FormatTemplate("{tracknumber:02}. {artist} - {title}{explicit}", map[string]string{
+		"tracknumber": "3",
+		"artist":      "Fleetwood Mac",
+		"title":       "Dreams",
+		"explicit":    "",
+	})
+	if got != "03. Fleetwood Mac - Dreams" {
+		t.Fatalf("got %q", got)
+	}
+}
+
+func TestCleanName(t *testing.T) {
+	got := CleanName(" Dreams/Live ", Config{RestrictCharacters: false, TruncateTo: 120})
+	if got != "Dreams_Live" {
+		t.Fatalf("got %q", got)
+	}
+}