5 files changed, 129 insertions, 6 deletions

diff --git a/service/src/main/java/market/guess/service/LocalGuessMarketContext.java b/service/src/main/java/market/guess/service/LocalGuessMarketContext.java
index f04324b..c85dadf 100644
--- a/service/src/main/java/market/guess/service/LocalGuessMarketContext.java
+++ b/service/src/main/java/market/guess/service/LocalGuessMarketContext.java
@@ -3,10 +3,10 @@ package market.guess.service;
 import java.math.BigDecimal;
 import java.time.Instant;
 import market.guess.api.GuessMarketContext;
-import market.guess.api.PurchaseReceiptDTO;
 import market.guess.api.Result;
-import market.guess.api.TradeRowDTO;
 import market.guess.model.event.EventDetailDTO;
+import market.guess.model.market.PurchaseReceiptDTO;
+import market.guess.model.market.TradeRowDTO;
 import market.guess.service.catalog.infrastructure.MarketContext;
 import market.guess.service.domain.Order;
 import market.guess.service.fulfillment.FulfillmentContext;
diff --git a/service/src/main/java/market/guess/service/catalog/infrastructure/adapter/LedgerMapper.java b/service/src/main/java/market/guess/service/catalog/infrastructure/adapter/LedgerMapper.java
new file mode 100644
index 0000000..5a46540
--- /dev/null
+++ b/service/src/main/java/market/guess/service/catalog/infrastructure/adapter/LedgerMapper.java
@@ -0,0 +1,10 @@
+package market.guess.service.catalog.infrastructure.adapter;
+
+import market.guess.model.ledger.LedgerDTO;
+import market.guess.service.ledger.Ledger;
+import org.mapstruct.Mapper;
+
+@Mapper
+public interface LedgerMapper {
+  LedgerDTO ledgerToLedgerDTO(Ledger ledger);
+}
diff --git a/service/src/main/java/market/guess/service/domain/Event.java b/service/src/main/java/market/guess/service/domain/Event.java
index 1e17457..4517a4e 100644
--- a/service/src/main/java/market/guess/service/domain/Event.java
+++ b/service/src/main/java/market/guess/service/domain/Event.java
@@ -4,13 +4,13 @@ import java.math.BigDecimal;
 import java.time.Instant;
 import java.util.ArrayList;
 import java.util.List;
-import market.guess.api.MarketDTO;
-import market.guess.api.MarketStateDTO;
-import market.guess.api.TradeRowDTO;
 import market.guess.model.event.CommissionTiming;
 import market.guess.model.event.EventStatus;
 import market.guess.model.event.EventSummaryDTO;
 import market.guess.model.ledger.LedgerType;
+import market.guess.model.market.MarketDTO;
+import market.guess.model.market.MarketStateDTO;
+import market.guess.model.market.TradeRowDTO;
 import market.guess.service.helpers.BigDecimalOptions;
 import market.guess.service.helpers.InstantOptions;
 import market.guess.service.ledger.Ledger;
diff --git a/service/src/main/java/market/guess/service/domain/Market.java b/service/src/main/java/market/guess/service/domain/Market.java
index 3ff7e2d..c5960e3 100644
--- a/service/src/main/java/market/guess/service/domain/Market.java
+++ b/service/src/main/java/market/guess/service/domain/Market.java
@@ -1,7 +1,7 @@
 package market.guess.service.domain;
 
 import java.math.BigDecimal;
-import market.guess.api.MarketDTO;
+import market.guess.model.market.MarketDTO;
 
 public final class Market {
   private final String key;
diff --git a/service/src/test/java/market/guess/service/catalog/infrastructure/adapter/LedgerMapperTest.java b/service/src/test/java/market/guess/service/catalog/infrastructure/adapter/LedgerMapperTest.java
new file mode 100644
index 0000000..976442c
--- /dev/null
+++ b/service/src/test/java/market/guess/service/catalog/infrastructure/adapter/LedgerMapperTest.java
@@ -0,0 +1,113 @@
+package market.guess.service.catalog.infrastructure.adapter;
+
+import static org.junit.Assert.assertEquals;
+import static org.junit.Assert.assertFalse;
+import static org.junit.Assert.assertNull;
+import static org.junit.Assert.assertTrue;
+
+import java.math.BigDecimal;
+import java.time.Instant;
+import java.util.List;
+import market.guess.model.ledger.LedgerDTO;
+import market.guess.model.ledger.LedgerEntryDTO;
+import market.guess.model.ledger.LedgerType;
+import market.guess.service.ledger.Ledger;
+import market.guess.service.ledger.LedgerEntry;
+import org.junit.Test;
+import org.mapstruct.factory.Mappers;
+
+public class LedgerMapperTest {
+
+  private final LedgerMapper mapper = Mappers.getMapper(LedgerMapper.class);
+
+  @Test
+  public void nullLedgerMapsToNull() {
+    assertNull(mapper.ledgerToLedgerDTO(null));
+  }
+
+  @Test
+  public void mapsOwnerAndBalanceAsStrings() {
+    Ledger ledger = new Ledger("alice", new BigDecimal("100"));
+
+    LedgerDTO dto = mapper.ledgerToLedgerDTO(ledger);
+
+    assertEquals("alice", dto.owner());
+    assertEquals("100.00", dto.balance());
+  }
+
+  @Test
+  public void emptyEntriesMapToEmptyList() {
+    Ledger ledger = new Ledger("alice", new BigDecimal("0"));
+
+    LedgerDTO dto = mapper.ledgerToLedgerDTO(ledger);
+
+    assertTrue(dto.entries().isEmpty());
+  }
+
+  @Test
+  public void mapsEntryFieldsInOrder() {
+    Ledger ledger = new Ledger("bob", new BigDecimal("0"));
+    ledger.record(
+        new LedgerEntry(
+            1,
+            Instant.parse("2026-01-01T00:00:00Z"),
+            LedgerType.DEPOSIT,
+            new BigDecimal("50.00"),
+            new BigDecimal("50.00"),
+            "first"));
+    ledger.record(
+        new LedgerEntry(
+            2,
+            Instant.parse("2026-01-02T00:00:00Z"),
+            LedgerType.PURCHASE,
+            new BigDecimal("-20.00"),
+            new BigDecimal("30.00"),
+            "second"));
+
+    List<LedgerEntryDTO> entries = mapper.ledgerToLedgerDTO(ledger).entries();
+
+    assertEquals(2, entries.size());
+    LedgerEntryDTO first = entries.get(0);
+    assertEquals(LedgerType.DEPOSIT, first.type());
+    assertEquals("50.00", first.amount());
+    assertEquals("50.00", first.balanceAfter());
+    assertEquals("first", first.note());
+    LedgerEntryDTO second = entries.get(1);
+    assertEquals(LedgerType.PURCHASE, second.type());
+    assertEquals("-20.00", second.amount());
+    assertEquals("30.00", second.balanceAfter());
+    assertEquals("second", second.note());
+  }
+
+  @Test
+  public void nullAmountAndBalanceAfterMapToNullStrings() {
+    Ledger ledger = new Ledger("carol", new BigDecimal("0"));
+    ledger.record(new LedgerEntry(1, Instant.now(), LedgerType.REFUND, null, null, null));
+
+    LedgerEntryDTO entry = mapper.ledgerToLedgerDTO(ledger).entries().get(0);
+
+    assertNull(entry.amount());
+    assertNull(entry.balanceAfter());
+  }
+
+  /**
+   * LedgerEntry.id/time and Ledger's account-blocked state have no matching AccountDTO/
+   * LedgerEntryDTO source property, so MapStruct leaves them at their Java defaults. This pins that
+   * known gap; once the mapper is taught to fill seq/at/blocked, update these assertions instead of
+   * deleting them.
+   */
+  @Test
+  public void unmappedTargetPropertiesFallBackToDefaults() {
+    Ledger ledger = new Ledger("dave", new BigDecimal("0"));
+    ledger.record(
+        new LedgerEntry(
+            7, Instant.now(), LedgerType.COMMISSION, BigDecimal.ONE, BigDecimal.ONE, "n"));
+
+    LedgerDTO dto = mapper.ledgerToLedgerDTO(ledger);
+
+    assertFalse(dto.blocked());
+    LedgerEntryDTO entry = dto.entries().get(0);
+    assertEquals(0L, entry.seq());
+    assertNull(entry.at());
+  }
+}