Add spendable to notes listing

lib/src/lightclient.rs

@@ -817,6 +817,8 @@ impl LightClient {
         let mut unspent_notes: Vec<JsonValue> = vec![];
         let mut spent_notes  : Vec<JsonValue> = vec![];
         let mut pending_notes: Vec<JsonValue> = vec![];
+        
+        let anchor_height: i32 = self.wallet.read().unwrap().get_anchor_height() as i32;
 
         {
             // Collect Sapling notes
@@ -834,6 +836,7 @@ impl LightClient {
                                 "value"              => nd.note.value,
                                 "is_change"          => nd.is_change,
                                 "address"            => LightWallet::note_address(self.config.hrp_sapling_address(), nd),
+                                "spendable"          => wtx.block <= anchor_height && nd.spent.is_none() && nd.unconfirmed_spent.is_none(),
                                 "spent"              => nd.spent.map(|spent_txid| format!("{}", spent_txid)),
                                 "spent_at_height"    => nd.spent_at_height.map(|h| format!("{}", h)),
                                 "unconfirmed_spent"  => nd.unconfirmed_spent.map(|spent_txid| format!("{}", spent_txid)),

lib/src/lightwallet.rs

@@ -733,6 +733,14 @@ impl LightWallet {
         }
     }
 
+    /// Get the height of the anchor block
+    pub fn get_anchor_height(&self) -> u32 {
+        match self.get_target_height_and_anchor_offset() {
+            Some((height, anchor_offset)) => height - anchor_offset as u32 - 1,
+            None => return 0,
+        }
+    }
+
     pub fn memo_str(memo: &Option<Memo>) -> Option<String> {
         match memo {
             Some(memo) => {
@@ -1003,10 +1011,7 @@ impl LightWallet {
     }
 
     pub fn spendable_zbalance(&self, addr: Option<String>) -> u64 {
-        let anchor_height = match self.get_target_height_and_anchor_offset() {
-            Some((height, anchor_offset)) => height - anchor_offset as u32 - 1,
-            None => return 0,
-        };
+        let anchor_height = self.get_anchor_height();
 
         self.txs
             .read()