export: allow to import a backup from a simple descriptor

liana-gui/src/backup.rs

@@ -1,7 +1,10 @@
 use chrono::{Duration, Utc};
-use liana::miniscript::{
-    self,
-    bitcoin::{bip32::Fingerprint, Network, Txid},
+use liana::{
+    descriptors::LianaDescriptor,
+    miniscript::{
+        self,
+        bitcoin::{bip32::Fingerprint, Network, Txid},
+    },
 };
 use lianad::{
     bip329,
@@ -111,6 +114,23 @@ impl Debug for Backup {
 }
 
 impl Backup {
+    /// Create a Backup from a descriptor
+    ///
+    /// # Arguments
+    /// * `descriptor` - the descriptor
+    /// * `network` - the network
+    pub fn from_descriptor(descriptor: LianaDescriptor, network: Network) -> Self {
+        let account = Account::new(descriptor.to_string());
+        Backup {
+            name: None,
+            alias: None,
+            accounts: vec![account],
+            network,
+            date: None,
+            proprietary: Default::default(),
+            version: default_version(),
+        }
+    }
     /// Create a Backup from the Installer context
     ///
     /// # Arguments

liana-gui/src/export.rs

@@ -246,7 +246,7 @@ pub enum Progress {
     WalletFromBackup(
         (
             LianaDescriptor,
-            Network,
+            Option<Network>,
             HashMap<Fingerprint, settings::KeySetting>,
             Backup,
         ),
@@ -1045,13 +1045,33 @@ pub async fn wallet_from_backup(
 
     let backup: Result<Backup, _> = serde_json::from_str(&backup_str);
     let backup = match backup {
-        Ok(psbt) => psbt,
+        Ok(b) => b,
         Err(e) => {
-            return Err(Error::BackupImport(format!("{:?}", e)));
+            // try to import as bare descriptor
+            let descr = LianaDescriptor::from_str(&backup_str);
+            match descr {
+                Ok(descr) => {
+                    let network = if descr.all_xpubs_net_is(Network::Bitcoin) {
+                        Network::Bitcoin
+                    } else {
+                        Network::Signet
+                    };
+                    Backup::from_descriptor(descr, network)
+                }
+                Err(e2) => {
+                    return Err(Error::BackupImport(format!(
+                        "A backup or descriptor file is expected: {e}, {e2}"
+                    )));
+                }
+            }
         }
     };
 
-    let network = backup.network;
+    let network = if backup.network == Network::Bitcoin {
+        Some(backup.network)
+    } else {
+        None
+    };
 
     let account = match backup.accounts.len() {
         0 => {

liana-gui/src/installer/step/descriptor/mod.rs

@@ -120,12 +120,26 @@ impl Step for ImportDescriptor {
             }
             Message::ImportExport(ImportExportMessage::Progress(Progress::WalletFromBackup(r))) => {
                 let (descriptor, network, aliases, backup) = r;
-                if self.network == network {
-                    self.imported_backup = Some(backup);
-                    self.imported_descriptor.value = descriptor.to_string();
-                    self.imported_aliases = Some(aliases);
+                if let Some(n) = network {
+                    if self.network == n {
+                        self.imported_backup = Some(backup);
+                        self.imported_descriptor.value = descriptor.to_string();
+                        self.imported_aliases = Some(aliases);
+                    } else {
+                        self.error =
+                            Some("Backup network do not match the selected network!".into());
+                    }
                 } else {
-                    self.error = Some("Backup network do not match the selected network!".into());
+                    // The backup have been inferred from a bare descriptor, we check whether
+                    // the descriptor match any test network
+                    if self.network != Network::Bitcoin {
+                        self.imported_backup = Some(backup);
+                        self.imported_descriptor.value = descriptor.to_string();
+                        self.imported_aliases = Some(aliases);
+                    } else {
+                        self.error =
+                            Some("Backup network do not match the selected network!".into());
+                    }
                 }
             }
             Message::ImportExport(m) => {