/rest/utxos: sort utxos by lastActivity

src/main/java/com/samourai/whirlpool/cli/api/protocol/beans/ApiWallet.java

 package com.samourai.whirlpool.cli.api.protocol.beans;
 
 import com.samourai.whirlpool.client.wallet.beans.WhirlpoolUtxo;
-import com.samourai.whirlpool.client.wallet.beans.WhirlpoolUtxoPriorityComparator;
 import java.util.Collection;
+import java.util.Comparator;
 import java.util.stream.Collectors;
 
 public class ApiWallet {
@@ -10,11 +10,12 @@ public class ApiWallet {
   private long balance;
   private String zpub;
 
-  public ApiWallet(Collection<WhirlpoolUtxo> whirlpoolUtxos, String zpub) {
+  public ApiWallet(
+      Collection<WhirlpoolUtxo> whirlpoolUtxos, String zpub, Comparator<WhirlpoolUtxo> comparator) {
     this.utxos =
         whirlpoolUtxos
             .stream()
-            .sorted(new WhirlpoolUtxoPriorityComparator())
+            .sorted(comparator)
             .map(whirlpoolUtxo -> new ApiUtxo(whirlpoolUtxo))
             .collect(Collectors.toList());
     this.balance =

src/main/java/com/samourai/whirlpool/cli/api/protocol/rest/ApiWalletStateResponse.java

@@ -2,7 +2,6 @@ package com.samourai.whirlpool.cli.api.protocol.rest;
 
 import com.samourai.whirlpool.cli.api.protocol.beans.ApiUtxo;
 import com.samourai.whirlpool.client.wallet.beans.MixOrchestratorState;
-import com.samourai.whirlpool.client.wallet.beans.WhirlpoolUtxoPriorityComparator;
 import com.samourai.whirlpool.client.wallet.beans.WhirlpoolWalletState;
 import java.util.Collection;
 import java.util.stream.Collectors;
@@ -28,7 +27,6 @@ public class ApiWalletStateResponse {
         mixState
             .getUtxosMixing()
             .stream()
-            .sorted(new WhirlpoolUtxoPriorityComparator())
             .map(whirlpoolUtxo -> new ApiUtxo(whirlpoolUtxo))
             .collect(Collectors.toList());
   }

src/main/java/com/samourai/whirlpool/cli/api/protocol/rest/ApiWalletUtxosResponse.java

 package com.samourai.whirlpool.cli.api.protocol.rest;
 
+import com.google.common.primitives.Ints;
 import com.samourai.whirlpool.cli.api.protocol.beans.ApiWallet;
 import com.samourai.whirlpool.client.wallet.WhirlpoolWallet;
+import com.samourai.whirlpool.client.wallet.beans.WhirlpoolUtxo;
+import java.util.Comparator;
+import java8.lang.Longs;
 
 public class ApiWalletUtxosResponse {
   private ApiWallet deposit;
@@ -9,11 +13,34 @@ public class ApiWalletUtxosResponse {
   private ApiWallet postmix;
 
   public ApiWalletUtxosResponse(WhirlpoolWallet whirlpoolWallet) throws Exception {
+    Comparator<WhirlpoolUtxo> comparator =
+        (o1, o2) -> {
+          // last activity first
+          if (o1.getLastActivity() != null || o2.getLastActivity() != null) {
+            if (o1.getLastActivity() != null && o2.getLastActivity() == null) {
+              return -1;
+            }
+            if (o2.getLastActivity() != null && o1.getLastActivity() == null) {
+              return 1;
+            }
+            int compare = Longs.compare(o2.getLastActivity(), o1.getLastActivity());
+            if (compare != 0) {
+              return compare;
+            }
+          }
+
+          // last confirmed
+          return Ints.compare(o1.getUtxo().confirmations, o2.getUtxo().confirmations);
+        };
     this.deposit =
-        new ApiWallet(whirlpoolWallet.getUtxosDeposit(), whirlpoolWallet.getZpubDeposit());
-    this.premix = new ApiWallet(whirlpoolWallet.getUtxosPremix(), whirlpoolWallet.getZpubPremix());
+        new ApiWallet(
+            whirlpoolWallet.getUtxosDeposit(), whirlpoolWallet.getZpubDeposit(), comparator);
+    this.premix =
+        new ApiWallet(
+            whirlpoolWallet.getUtxosPremix(), whirlpoolWallet.getZpubPremix(), comparator);
     this.postmix =
-        new ApiWallet(whirlpoolWallet.getUtxosPostmix(), whirlpoolWallet.getZpubPostmix());
+        new ApiWallet(
+            whirlpoolWallet.getUtxosPostmix(), whirlpoolWallet.getZpubPostmix(), comparator);
   }
 
   public ApiWallet getDeposit() {