fix finding the earliest transaction by date

[mobile-ledger.git] / app / src / main / java / net / ktnx / mobileledger / async / TransactionDateFinder.java

diff --git a/app/src/main/java/net/ktnx/mobileledger/async/TransactionDateFinder.java b/app/src/main/java/net/ktnx/mobileledger/async/TransactionDateFinder.java
index e90a2ae32381032b6dcff00386ed3dce4e8a621f..2bce07e1ca08fc4218aa7aba911491c9fc2c5c87 100644 (file)
--- a/app/src/main/java/net/ktnx/mobileledger/async/TransactionDateFinder.java
+++ b/app/src/main/java/net/ktnx/mobileledger/async/TransactionDateFinder.java
@@ -1,5 +1,5 @@
 /*
- * Copyright © 2020 Damyan Ivanov.
+ * Copyright © 2021 Damyan Ivanov.
  * This file is part of MoLe.
  * MoLe is free software: you can distribute it and/or modify it
  * under the term of the GNU General Public License as published by
@@ -24,6 +24,8 @@ import net.ktnx.mobileledger.ui.MainModel;
 import net.ktnx.mobileledger.utils.Logger;
 import net.ktnx.mobileledger.utils.SimpleDate;
 
+import org.jetbrains.annotations.NotNull;
+
 import java.util.Collections;
 import java.util.Comparator;
 import java.util.List;
@@ -46,8 +48,9 @@ public class TransactionDateFinder extends AsyncTask<TransactionDateFinder.Param
         List<TransactionListItem> transactions = Objects.requireNonNull(
                 param[0].model.getDisplayedTransactions()
                               .getValue());
+        final int transactionCount = transactions.size();
         Logger.debug("go-to-date",
-                String.format(Locale.US, "List contains %d transactions", transactions.size()));
+                String.format(Locale.US, "List contains %d transactions", transactionCount));
 
         TransactionListItem target = new TransactionListItem(date, true);
         int found =
@@ -55,13 +58,13 @@ public class TransactionDateFinder extends AsyncTask<TransactionDateFinder.Param
         if (found >= 0)
             return found;
         else
-            return 1 - found;
+            return -1 - found;
     }
 
     public static class Params {
-        public MainModel model;
-        public SimpleDate date;
-        public Params(MainModel model, SimpleDate date) {
+        public final MainModel model;
+        public final SimpleDate date;
+        public Params(@NotNull MainModel model, @NotNull SimpleDate date) {
             this.model = model;
             this.date = date;
         }
@@ -69,21 +72,27 @@ public class TransactionDateFinder extends AsyncTask<TransactionDateFinder.Param
 
     static class TransactionListItemComparator implements Comparator<TransactionListItem> {
         @Override
-        public int compare(TransactionListItem a, TransactionListItem b) {
+        public int compare(@NotNull TransactionListItem a, @NotNull TransactionListItem b) {
+            final TransactionListItem.Type aType = a.getType();
+            if (aType == TransactionListItem.Type.HEADER)
+                return +1;
+            final TransactionListItem.Type bType = b.getType();
+            if (bType == TransactionListItem.Type.HEADER)
+                return -1;
             final SimpleDate aDate = a.getDate();
             final SimpleDate bDate = b.getDate();
             int res = aDate.compareTo(bDate);
             if (res != 0)
                 return -res;    // transactions are reverse sorted by date
 
-            if (a.getType() == TransactionListItem.Type.DELIMITER) {
-                if (b.getType() == TransactionListItem.Type.DELIMITER)
+            if (aType == TransactionListItem.Type.DELIMITER) {
+                if (bType == TransactionListItem.Type.DELIMITER)
                     return 0;
                 else
                     return -1;
             }
             else {
-                if (b.getType() == TransactionListItem.Type.DELIMITER)
+                if (bType == TransactionListItem.Type.DELIMITER)
                     return +1;
                 else
                     return 0;