fix #2: add --create-config to create a default config

cmd/io.go

@@ -0,0 +1,52 @@
+/*
+Copyright © 2026 Thomas von Dein
+
+This program is free software: you can redistribute it and/or modify
+it under the terms of the GNU General Public License as published by
+the Free Software Foundation, either version 3 of the License, or
+(at your option) any later version.
+
+This program is distributed in the hope that it will be useful,
+but WITHOUT ANY WARRANTY; without even the implied warranty of
+MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+GNU General Public License for more details.
+
+You should have received a copy of the GNU General Public License
+along with this program. If not, see <http://www.gnu.org/licenses/>.
+*/
+package cmd
+
+import (
+	"fmt"
+	"log"
+	"os"
+)
+
+func FileExists(filename string) bool {
+	info, err := os.Stat(filename)
+
+	if err != nil {
+		// return false on any error
+		return false
+	}
+
+	return !info.IsDir()
+}
+
+func WriteFile(filename string, content []byte) error {
+	var err error
+
+	fd, err := os.OpenFile(filename, os.O_WRONLY|os.O_CREATE|os.O_TRUNC, 0755)
+	if err != nil {
+		return fmt.Errorf("failed to open file %s for writing: %w", filename, err)
+	}
+	defer func() {
+		if err := fd.Close(); err != nil {
+			log.Fatal(err)
+		}
+	}()
+
+	_, err = fd.Write(content)
+
+	return err
+}