feat: refactor app in a separate package

internal/app/questions.go

@@ -0,0 +1,35 @@
+package app
+
+import (
+	"strings"
+
+	"github.com/miekg/dns"
+)
+
+// LoadFallbacks sets fallbacks for options
+// that are not specified by the user but necessary
+// for the resolver.
+func (app *App) LoadFallbacks() {
+	if len(app.QueryFlags.QTypes) == 0 {
+		app.QueryFlags.QTypes = append(app.QueryFlags.QTypes, "A")
+	}
+	if len(app.QueryFlags.QClasses) == 0 {
+		app.QueryFlags.QClasses = append(app.QueryFlags.QClasses, "IN")
+	}
+}
+
+// PrepareQuestions takes a list of query names, query types and query classes
+// and prepare a question for each combination of the above.
+func (app *App) PrepareQuestions() {
+	for _, n := range app.QueryFlags.QNames {
+		for _, t := range app.QueryFlags.QTypes {
+			for _, c := range app.QueryFlags.QClasses {
+				app.Questions = append(app.Questions, dns.Question{
+					Name:   n,
+					Qtype:  dns.StringToType[strings.ToUpper(t)],
+					Qclass: dns.StringToClass[strings.ToUpper(c)],
+				})
+			}
+		}
+	}
+}