Implemented decrypt command (fixes #2)

src/calanonsync/settings.go

@@ -6,7 +6,6 @@ import (
 	"crypto/rand"
 	"encoding/base64"
 	"encoding/json"
-	"fmt"
 	"github.com/spf13/cobra"
 	"golang.org/x/crypto/ssh/terminal"
 	"io"
@@ -192,8 +191,30 @@ func runSettingsEncryption(cmd *cobra.Command, args []string) {
 	if err != nil {
 		panic(err)
 	}
+
+	log.Println("Settings encrypted")
 }
 
 func runSettingsDecryption(cmd *cobra.Command, args []string) {
-	fmt.Println("Decrypt")
+	s := LoadSettings()
+
+	// Rewrite the settings file.
+	f, err := os.OpenFile(settingsName, os.O_WRONLY|os.O_TRUNC, 0600)
+	if err != nil {
+		log.Fatalf("Could not rewrite settings: %s\n", err)
+	}
+	defer f.Close()
+	e := json.NewEncoder(f)
+	e.SetIndent("", "  ")
+	err = e.Encode(&s)
+	if err != nil {
+		panic(err)
+	}
+
+	err = os.Remove(keyName)
+	if err != nil {
+		log.Fatalf("Could not remove key file: %s\n", err)
+	}
+
+	log.Println("Settings decrypted")
 }