Feat: Perfect privacy support (#606)

internal/updater/providers/perfectprivacy/filename.go

@@ -0,0 +1,20 @@
+package perfectprivacy
+
+import (
+	"strings"
+	"unicode"
+)
+
+func parseFilename(fileName string) (city string) {
+	const suffix = ".conf"
+	s := strings.TrimSuffix(fileName, suffix)
+
+	for i, r := range s {
+		if unicode.IsDigit(r) {
+			s = s[:i]
+			break
+		}
+	}
+
+	return s
+}