feat(key-wallet): reserve receive addresses on hand-out

key-wallet-ffi/src/address_pool.rs

@@ -264,9 +264,9 @@ fn address_info_to_ffi(info: &AddressInfo) -> FFIAddressInfo {
         public_key_len,
         index: info.index,
         path: path_str,
-        used: info.used,
+        used: info.is_used(),
         generated_at: info.generated_at,
-        used_at: info.used_at.unwrap_or(0),
+        used_at: info.used_at().unwrap_or(0),
         tx_count: info.tx_count,
         total_received: info.total_received,
         total_sent: info.total_sent,
@@ -879,6 +879,7 @@ pub unsafe extern "C" fn address_info_array_free(infos: *mut *mut FFIAddressInfo
 mod tests {
     use super::*;
     use dash_network::ffi::FFINetwork;
+    use key_wallet::managed_account::address_pool::AddressState;
 
     #[test]
     fn test_address_pool_type_values() {
@@ -914,9 +915,8 @@ mod tests {
             public_key: Some(PublicKeyType::ECDSA(vec![0x02, 0x03, 0x04])),
             index: 0,
             path: test_path,
-            used: false,
+            state: AddressState::Available,
             generated_at: 1234567890,
-            used_at: None,
             tx_count: 0,
             total_received: 0,
             total_sent: 0,

key-wallet-ffi/src/error.rs

@@ -250,9 +250,10 @@ impl From<key_wallet::Error> for FFIError {
             Error::InvalidNetwork => FFIErrorCode::InvalidNetwork,
             Error::InvalidAddress(_) => FFIErrorCode::InvalidAddress,
             Error::Serialization(_) => FFIErrorCode::SerializationError,
-            Error::WatchOnly | Error::CoinJoinNotEnabled | Error::NoKeySource => {
-                FFIErrorCode::InvalidState
-            }
+            Error::InvalidState(_)
+            | Error::WatchOnly
+            | Error::CoinJoinNotEnabled
+            | Error::NoKeySource => FFIErrorCode::InvalidState,
             Error::Bip32(_)
             | Error::Slip10(_)
             | Error::BLS(_)

key-wallet-manager/src/events.rs

@@ -434,7 +434,7 @@ mod project_derived_addresses_tests {
     use super::*;
     use key_wallet::account::StandardAccountType;
     use key_wallet::bip32::{ChildNumber, DerivationPath};
-    use key_wallet::managed_account::address_pool::AddressInfo;
+    use key_wallet::managed_account::address_pool::{AddressInfo, AddressState};
     use std::collections::BTreeMap;
 
     /// Compressed encoding of the secp256k1 generator point (G).
@@ -488,9 +488,8 @@ mod project_derived_addresses_tests {
                 public_key: Some(PublicKeyType::ECDSA(pubkey_bytes)),
                 index,
                 path,
-                used: false,
+                state: AddressState::Available,
                 generated_at: 0,
-                used_at: None,
                 tx_count: 0,
                 total_received: 0,
                 total_sent: 0,

key-wallet/src/error.rs

@@ -37,6 +37,8 @@ pub enum Error {
     Serialization(String),
     /// Invalid parameter
     InvalidParameter(String),
+    /// Internal invariant violated (inconsistent wallet state)
+    InvalidState(String),
     /// Watch-only wallet (no private keys available)
     WatchOnly,
     /// No key source available for address derivation
@@ -61,6 +63,7 @@ impl fmt::Display for Error {
             Error::CoinJoinNotEnabled => write!(f, "CoinJoin not enabled for this account"),
             Error::Serialization(s) => write!(f, "Serialization error: {}", s),
             Error::InvalidParameter(s) => write!(f, "Invalid parameter: {}", s),
+            Error::InvalidState(s) => write!(f, "Invalid state: {}", s),
             Error::WatchOnly => write!(f, "Watch-only wallet: private keys not available"),
             Error::NoKeySource => write!(f, "No key source available for address derivation"),
         }