18 files changed, 118 insertions, 138 deletions

diff --git a/service/src/main/java/market/guess/service/LocalGuessMarketContext.java b/service/src/main/java/market/guess/service/LocalGuessMarketContext.java
index 8f97432..3feef6a 100644
--- a/service/src/main/java/market/guess/service/LocalGuessMarketContext.java
+++ b/service/src/main/java/market/guess/service/LocalGuessMarketContext.java
@@ -1,25 +1,21 @@
 package market.guess.service;
 
-import java.nio.file.Path;
-import java.util.List;
-import market.guess.api.AccountDTO;
-import market.guess.api.EventDetailDTO;
 import market.guess.api.GuessMarketContext;
-import market.guess.api.LoadResultDTO;
-import market.guess.api.ProblemDTO;
 import market.guess.api.PurchaseReceiptDTO;
 import market.guess.api.Result;
+import market.guess.api.TradeRowDTO;
+import market.guess.model.event.EventDetailDTO;
 import market.guess.service.infrastructure.MarketContext;
+import market.guess.service.matching.OrderMatchingContext;
 
 public final class LocalGuessMarketContext implements GuessMarketContext {
-
-  private final TradingOperation tradingOperation;
+  private final OrderMatchingContext orderMatching;
   private final MarketContext context;
 
-  public LocalGuessMarketContext(MarketContext context, TradingOperation tradingOperation) {
+  public LocalGuessMarketContext(MarketContext context, OrderMatchingContext orderMatching) {
     super();
     this.context = context;
-    this.tradingOperation = tradingOperation;
+    this.orderMatching = orderMatching;
   }
 
   @Override
@@ -28,42 +24,46 @@ public final class LocalGuessMarketContext implements GuessMarketContext {
     var optional = context.getEvents().get(eventKey);
 
     var userOptional = context.getUsers().get(userName);
-    if (optional.isEmpty() || userOptional.isEmpty()) Result.error("Unable to find user/event.");
+    if (optional.isEmpty() || userOptional.isEmpty())
+      return Result.error("Unable to find user/event.");
 
     var event = optional.get();
     var user = userOptional.get();
     var option = event.getOption(optionKey);
-    var trade = tradingOperation.buy(event, user, option, quantity);
-    return Result.ok(new PurchaseReceiptDTO());
+
+    var trades = orderMatching.submitOrder(user, event, option, quantity);
+    return Result.ok(
+        new PurchaseReceiptDTO(
+            trades.stream()
+                .map(
+                    t ->
+                        new TradeRowDTO(
+                            t.at().toString(),
+                            t.userName(),
+                            t.optionName(),
+                            String.valueOf(t.quantity()),
+                            t.totalPaid().toPlainString()))
+                .toList(),
+            event.toMarketState()));
   }
 
   @Override
-  public Result<EventDetailDTO> closeEvent(
+  public Result<EventDetailDTO> settleEvent(
       String userName, String eventKey, String winningOptionKey) {
-    throw new UnsupportedOperationException("Unimplemented method 'account'");
-  }
+    var optional = context.getEvents().get(eventKey);
 
-  @Override
-  public Result<AccountDTO> account(String userName) {
-    throw new UnsupportedOperationException("Unimplemented method 'account'");
-  }
+    if (optional.isEmpty()) return Result.error("Unknown event.");
 
-  @Override
-  public Result<Void> saveState(Path path) {
-    context.save();
-    return Result.ok();
-  }
+    var event = optional.get();
+    if (event.canSettle(userName)) {
 
-  @Override
-  public Result<LoadResultDTO> restoreState(Path path) {
+      var payout = event.getPayout();
 
-    try {
-      context.load();
-    } catch (Exception e) {
-      return Result.error(
-          "Failed to load.",
-          LoadResultDTO.failure(path.toString(), List.of(new ProblemDTO("", e.getMessage(), ""))));
+      return Result.ok(
+          new EventDetailDTO(
+              event.toEventSummary(), event.toMarketState(), event.getHistory(), ""));
     }
-    return Result.ok(LoadResultDTO.success(path.toString(), context.getEvents().getAll().size()));
+
+    return Result.error("Couldn't settle event.");
   }
 }
diff --git a/service/src/main/java/market/guess/service/TradingOperation.java b/service/src/main/java/market/guess/service/TradingOperation.java
deleted file mode 100644
index 63572c0..0000000
--- a/service/src/main/java/market/guess/service/TradingOperation.java
+++ /dev/null
@@ -1,13 +0,0 @@
-package market.guess.service;
-
-import market.guess.service.domain.Event;
-import market.guess.service.domain.Market;
-import market.guess.service.domain.Settlement;
-import market.guess.service.domain.Trade;
-import market.guess.service.domain.User;
-
-public interface TradingOperation {
-  Trade buy(Event event, User user, Market Option, int quantity);
-
-  Settlement settle(Event event, String winningOption);
-}
diff --git a/service/src/main/java/market/guess/service/TradingOperationImpl.java b/service/src/main/java/market/guess/service/TradingOperationImpl.java
deleted file mode 100644
index 641a3a9..0000000
--- a/service/src/main/java/market/guess/service/TradingOperationImpl.java
+++ /dev/null
@@ -1,22 +0,0 @@
-package market.guess.service;
-
-import market.guess.service.domain.Event;
-import market.guess.service.domain.Market;
-import market.guess.service.domain.Settlement;
-import market.guess.service.domain.Trade;
-import market.guess.service.domain.User;
-
-public final class TradingOperationImpl implements TradingOperation {
-
-  @Override
-  public Trade buy(Event event, User user, Market Option, int quantity) {
-    // TODO Auto-generated method stub
-    throw new UnsupportedOperationException("Unimplemented method 'buy'");
-  }
-
-  @Override
-  public Settlement settle(Event event, String winningOption) {
-    // TODO Auto-generated method stub
-    throw new UnsupportedOperationException("Unimplemented method 'settle'");
-  }
-}
diff --git a/service/src/main/java/market/guess/service/LocalCatalogContext.java b/service/src/main/java/market/guess/service/catalog/LocalCatalogContext.java
index 15a5890..6035ce7 100644
--- a/service/src/main/java/market/guess/service/LocalCatalogContext.java
+++ b/service/src/main/java/market/guess/service/catalog/LocalCatalogContext.java
@@ -1,18 +1,17 @@
-package market.guess.service;
+package market.guess.service.catalog;
 
 import java.nio.file.Path;
 import java.util.List;
 import market.guess.api.CatalogContext;
-import market.guess.api.EventDetailDTO;
-import market.guess.api.EventSummaryDTO;
 import market.guess.api.LoadResultDTO;
 import market.guess.api.Result;
+import market.guess.model.event.EventDetailDTO;
+import market.guess.model.event.EventSummaryDTO;
 import market.guess.service.domain.Event;
 import market.guess.service.infrastructure.MarketContext;
 import market.guess.service.infrastructure.provider.Loader;
 
 public final class LocalCatalogContext implements CatalogContext {
-
   private final MarketContext context;
   private final Loader provider;
 
@@ -24,7 +23,7 @@ public final class LocalCatalogContext implements CatalogContext {
 
   @Override
   public Result<LoadResultDTO> loadEvents(Path path) {
-    return Result.ok(provider.load(path));
+    return provider.load(path);
   }
 
   @Override
@@ -42,4 +41,24 @@ public final class LocalCatalogContext implements CatalogContext {
     return Result.ok(
         new EventDetailDTO(event.toEventSummary(), event.toMarketState(), event.getHistory(), ""));
   }
+
+  @Override
+  public Result<Void> saveState(Path path) {
+    try {
+      context.save();
+    } catch (Exception e) {
+      return Result.error("Failed to save.", e.getMessage());
+    }
+    return Result.ok();
+  }
+
+  @Override
+  public Result<LoadResultDTO> restoreState(Path path) {
+    try {
+      context.load();
+    } catch (Exception e) {
+      return Result.error("Failed to load.", e.getMessage());
+    }
+    return Result.ok(new LoadResultDTO(path.toString(), context.getEvents().getAll().size()));
+  }
 }
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 5c98908..943328a 100644
--- a/service/src/main/java/market/guess/service/domain/Event.java
+++ b/service/src/main/java/market/guess/service/domain/Event.java
@@ -5,10 +5,10 @@ import java.time.Instant;
 import java.util.ArrayList;
 import java.util.List;
 import market.guess.api.CommissionTiming;
-import market.guess.api.EventStatus;
-import market.guess.api.EventSummaryDTO;
 import market.guess.api.MarketStateDTO;
 import market.guess.api.TradeRowDTO;
+import market.guess.model.event.EventStatus;
+import market.guess.model.event.EventSummaryDTO;
 import market.guess.service.ledger.Ledger;
 import market.guess.service.mechanism.TradingMechanism;
 
@@ -78,16 +78,12 @@ public final class Event {
     return commissionTiming;
   }
 
-  public TradingMechanism getMechanism() {
-    return mechanism;
-  }
-
   public List<Market> getMarkets() {
     return markets;
   }
 
   public List<String> getOptionsNames() {
-    return markets.stream().map(Market::getKey).toList();
+    return markets.stream().map(Market::getName).toList();
   }
 
   public Ledger getLedger() {
@@ -190,4 +186,16 @@ public final class Event {
         .findFirst()
         .orElseThrow(() -> new IllegalArgumentException("No such option."));
   }
+
+  public boolean canSettle(String userName) {
+    if (state != EventStatus.ACTIVE) return false;
+    if (marketMaker.equalsIgnoreCase(userName)) return true;
+
+    return false;
+  }
+
+  public BigDecimal getPayout() {
+    // TODO Auto-generated method stub
+    throw new UnsupportedOperationException("Unimplemented method 'getPayout'");
+  }
 }
diff --git a/service/src/main/java/market/guess/service/domain/MarketAction.java b/service/src/main/java/market/guess/service/domain/MarketAction.java
index c0aabd1..d1a0ad5 100644
--- a/service/src/main/java/market/guess/service/domain/MarketAction.java
+++ b/service/src/main/java/market/guess/service/domain/MarketAction.java
@@ -5,7 +5,7 @@ public record MarketAction(
 
   public static final String BUY = "BUY";
   public static final String SELL = "SELL";
-  public static final String CLOSE = "CLOSE";
+  public static final String SETTLE = "SETTLE";
 
   public static MarketAction buy(
       String at, String userName, String eventKey, String optionKey, long quantity) {
@@ -17,8 +17,8 @@ public record MarketAction(
     return new MarketAction(SELL, at, userName, eventKey, optionKey, quantity);
   }
 
-  public static MarketAction close(
+  public static MarketAction settle(
       String at, String userName, String eventKey, String winningOptionKey) {
-    return new MarketAction(CLOSE, at, userName, eventKey, winningOptionKey, 0);
+    return new MarketAction(SETTLE, at, userName, eventKey, winningOptionKey, 0);
   }
 }
diff --git a/service/src/main/java/market/guess/service/infrastructure/MarketContext.java b/service/src/main/java/market/guess/service/infrastructure/MarketContext.java
index d9fe3f8..7113803 100644
--- a/service/src/main/java/market/guess/service/infrastructure/MarketContext.java
+++ b/service/src/main/java/market/guess/service/infrastructure/MarketContext.java
@@ -10,6 +10,7 @@ import java.nio.file.Path;
 import java.nio.file.Paths;
 import java.time.Instant;
 import java.util.List;
+import market.guess.exception.GuessMarketException;
 import market.guess.service.domain.Event;
 import market.guess.service.domain.User;
 import market.guess.service.infrastructure.adapter.InstantTypeAdapter;
@@ -41,21 +42,19 @@ public final class MarketContext {
     return users;
   }
 
-  public void save() {
+  public void save() throws GuessMarketException {
     var path = Paths.get("test-file.json");
 
     try {
       if (path.getParent() != null) Files.createDirectories(path.getParent());
       Files.writeString(
-          path,
-          GSON.toJson(new Wrapper(events.getAll(), users.getAll())),
-          StandardCharsets.UTF_8);
+          path, GSON.toJson(new Wrapper(events.getAll(), users.getAll())), StandardCharsets.UTF_8);
     } catch (IOException e) {
-
+      throw new GuessMarketException("Failed to sove the file.");
     }
   }
 
-  public void load() {
+  public void load() throws GuessMarketException {
     try {
       var wrapper =
           GSON.fromJson(
@@ -71,9 +70,10 @@ public final class MarketContext {
         users.add(user);
       }
 
-    } catch (JsonSyntaxException | IOException e) {
-      // TODO Auto-generated catch block
-      e.printStackTrace();
+    } catch (JsonSyntaxException e) {
+      throw new GuessMarketException("The JSON file is malformed.");
+    } catch (IOException e) {
+      throw new GuessMarketException("Unable the file.");
     }
   }
 }
diff --git a/service/src/main/java/market/guess/service/infrastructure/mapper/v1/EventMapperV1.java b/service/src/main/java/market/guess/service/infrastructure/mapper/v1/EventMapperV1.java
index 7984c41..f049a0b 100644
--- a/service/src/main/java/market/guess/service/infrastructure/mapper/v1/EventMapperV1.java
+++ b/service/src/main/java/market/guess/service/infrastructure/mapper/v1/EventMapperV1.java
@@ -3,7 +3,7 @@ package market.guess.service.infrastructure.mapper.v1;
 import java.util.ArrayList;
 import java.util.List;
 import market.guess.api.CommissionTiming;
-import market.guess.api.EventStatus;
+import market.guess.model.event.EventStatus;
 import market.guess.service.domain.Event;
 import market.guess.service.domain.Market;
 import market.guess.service.infrastructure.mapper.Mapper;
diff --git a/service/src/main/java/market/guess/service/infrastructure/mapper/v2/EventMapperV2.java b/service/src/main/java/market/guess/service/infrastructure/mapper/v2/EventMapperV2.java
index 0dd8e43..7037c02 100644
--- a/service/src/main/java/market/guess/service/infrastructure/mapper/v2/EventMapperV2.java
+++ b/service/src/main/java/market/guess/service/infrastructure/mapper/v2/EventMapperV2.java
@@ -3,7 +3,7 @@ package market.guess.service.infrastructure.mapper.v2;
 import java.util.ArrayList;
 import java.util.List;
 import market.guess.api.CommissionTiming;
-import market.guess.api.EventStatus;
+import market.guess.model.event.EventStatus;
 import market.guess.service.domain.Event;
 import market.guess.service.domain.Market;
 import market.guess.service.infrastructure.mapper.Mapper;
diff --git a/service/src/main/java/market/guess/service/infrastructure/provider/LoadValidator.java b/service/src/main/java/market/guess/service/infrastructure/provider/LoadValidator.java
deleted file mode 100644
index c1c3895..0000000
--- a/service/src/main/java/market/guess/service/infrastructure/provider/LoadValidator.java
+++ /dev/null
@@ -1,22 +0,0 @@
-package market.guess.service.infrastructure.provider;
-
-import java.util.ArrayList;
-import java.util.Collections;
-import java.util.List;
-import market.guess.api.ProblemDTO;
-
-public final class LoadValidator {
-  private final List<ProblemDTO> problems = new ArrayList<>();
-
-  public void append(String code, String humanizedMessage, String location) {
-    problems.add(new ProblemDTO(code, humanizedMessage, location));
-  }
-
-  public boolean isValid() {
-    return problems.isEmpty();
-  }
-
-  public List<ProblemDTO> getIssues() {
-    return Collections.unmodifiableList(problems);
-  }
-}
diff --git a/service/src/main/java/market/guess/service/infrastructure/provider/Loader.java b/service/src/main/java/market/guess/service/infrastructure/provider/Loader.java
index 7588855..fcca92f 100644
--- a/service/src/main/java/market/guess/service/infrastructure/provider/Loader.java
+++ b/service/src/main/java/market/guess/service/infrastructure/provider/Loader.java
@@ -2,7 +2,8 @@ package market.guess.service.infrastructure.provider;
 
 import java.nio.file.Path;
 import market.guess.api.LoadResultDTO;
+import market.guess.api.Result;
 
 public interface Loader {
-  LoadResultDTO load(Path path);
+  Result<LoadResultDTO> load(Path path);
 }
diff --git a/service/src/main/java/market/guess/service/infrastructure/provider/v1/XMLLoaderV1.java b/service/src/main/java/market/guess/service/infrastructure/provider/v1/XMLLoaderV1.java
index 0d5bb9d..412a5d2 100644
--- a/service/src/main/java/market/guess/service/infrastructure/provider/v1/XMLLoaderV1.java
+++ b/service/src/main/java/market/guess/service/infrastructure/provider/v1/XMLLoaderV1.java
@@ -5,9 +5,9 @@ import jakarta.xml.bind.JAXBException;
 import java.nio.file.Files;
 import java.nio.file.Path;
 import market.guess.api.LoadResultDTO;
+import market.guess.api.Result;
 import market.guess.service.domain.User;
 import market.guess.service.infrastructure.mapper.v1.EventMapperV1;
-import market.guess.service.infrastructure.provider.LoadValidator;
 import market.guess.service.infrastructure.provider.Loader;
 import market.guess.service.infrastructure.repository.EventRepository;
 import market.guess.service.infrastructure.repository.UserRepository;
@@ -34,11 +34,11 @@ public final class XMLLoaderV1 implements Loader {
   }
 
   @Override
-  public LoadResultDTO load(Path path) {
-    var validator = new LoadValidator();
+  public Result<LoadResultDTO> load(Path path) {
+
     if (path.getFileName() == null
         || !path.getFileName().toString().toLowerCase().endsWith(".xml")) {
-      validator.append("NOT_XML", "The file must be an XML.", path.toString());
+      return Result.error("NOT_XML", "The file must be an XML.");
     }
 
     try (var stream = Files.newInputStream(path)) {
@@ -51,11 +51,9 @@ public final class XMLLoaderV1 implements Loader {
 
       userRepository.add(new User("Tester", 9_999_999));
 
-      return LoadResultDTO.success(path.toString(), eventRepository.getAll().size());
+      return Result.ok(new LoadResultDTO(path.toString(), eventRepository.getAll().size()));
     } catch (Exception e) {
-      validator.append("UNREADABLE", "The file could not be read.", path.toString());
+      return Result.error("UNREADABLE", "The file could not be read.");
     }
-
-    return LoadResultDTO.failure(path.toString(), validator.getIssues());
   }
 }
diff --git a/service/src/main/java/market/guess/service/ledger/LedgerContext.java b/service/src/main/java/market/guess/service/ledger/LedgerContext.java
index caecf55..12ec614 100644
--- a/service/src/main/java/market/guess/service/ledger/LedgerContext.java
+++ b/service/src/main/java/market/guess/service/ledger/LedgerContext.java
@@ -2,7 +2,7 @@ package market.guess.service.ledger;
 
 import java.math.BigDecimal;
 import java.time.Clock;
-import market.guess.api.LedgerType;
+import market.guess.model.ledger.LedgerType;
 import market.guess.service.infrastructure.repository.UserRepository;
 
 public final class LedgerContext {
diff --git a/service/src/main/java/market/guess/service/ledger/LedgerEntry.java b/service/src/main/java/market/guess/service/ledger/LedgerEntry.java
index 8008f20..79f12bf 100644
--- a/service/src/main/java/market/guess/service/ledger/LedgerEntry.java
+++ b/service/src/main/java/market/guess/service/ledger/LedgerEntry.java
@@ -2,7 +2,7 @@ package market.guess.service.ledger;
 
 import java.math.BigDecimal;
 import java.time.Instant;
-import market.guess.api.LedgerType;
+import market.guess.model.ledger.LedgerType;
 
 public final record LedgerEntry(
     int id,
diff --git a/service/src/main/java/market/guess/service/matching/OrderMatchingContext.java b/service/src/main/java/market/guess/service/matching/OrderMatchingContext.java
new file mode 100644
index 0000000..8882432
--- /dev/null
+++ b/service/src/main/java/market/guess/service/matching/OrderMatchingContext.java
@@ -0,0 +1,13 @@
+package market.guess.service.matching;
+
+import java.util.List;
+import market.guess.service.domain.Event;
+import market.guess.service.domain.Market;
+import market.guess.service.domain.Trade;
+import market.guess.service.domain.User;
+
+public interface OrderMatchingContext {
+  List<Trade> submitOrder(User user, Event event, Market market, int quantity);
+
+  boolean cancelOrder();
+}
diff --git a/service/src/main/java/market/guess/service/mechanism/OrderBookTradingMechanism.java b/service/src/main/java/market/guess/service/mechanism/OrderBookTradingMechanism.java
index 91d5110..43f4843 100644
--- a/service/src/main/java/market/guess/service/mechanism/OrderBookTradingMechanism.java
+++ b/service/src/main/java/market/guess/service/mechanism/OrderBookTradingMechanism.java
@@ -6,6 +6,7 @@ import java.util.ArrayList;
 import java.util.List;
 import market.guess.api.MechanismType;
 import market.guess.service.domain.BigDecimalOptions;
+import market.guess.service.domain.Trade;
 
 public final class OrderBookTradingMechanism implements TradingMechanism {
   public enum Side {
@@ -58,12 +59,12 @@ public final class OrderBookTradingMechanism implements TradingMechanism {
   }
 
   @Override
-  public TradeExecution buy(int optionIndex, int quantity) {
+  public Trade buy(int optionIndex, int quantity) {
     return match(optionIndex, Side.BUY, quantity, null, false);
   }
 
   /** Priced limit order — not on the shared interface, no engine call site yet. */
-  public TradeExecution placeOrder(int optionIndex, Side side, int quantity, BigDecimal price) {
+  public Trade placeOrder(int optionIndex, Side side, int quantity, BigDecimal price) {
     if (price.signum() < 0 || price.compareTo(BigDecimal.valueOf(d)) > 0) {
       throw new IllegalArgumentException("Price must be between 0 and " + d);
     }
@@ -97,7 +98,7 @@ public final class OrderBookTradingMechanism implements TradingMechanism {
     return book.isEmpty() ? null : book.get(0).price;
   }
 
-  private TradeExecution match(
+  private Trade match(
       int optionIndex, Side side, int quantity, BigDecimal limitPrice, boolean restRemainder) {
     var opposing = side == Side.BUY ? asks.get(optionIndex) : bids.get(optionIndex);
 
@@ -127,7 +128,8 @@ public final class OrderBookTradingMechanism implements TradingMechanism {
           new RestingOrder(limitPrice, quantity - filled));
     }
 
-    return new TradeExecution(filled, BigDecimalOptions.toMoney(proceeds));
+    return new Trade(
+        filled, null, null, null, null, filled, BigDecimalOptions.toMoney(proceeds), proceeds);
   }
 
   private static boolean crosses(Side side, BigDecimal restingPrice, BigDecimal limitPrice) {
diff --git a/service/src/main/java/market/guess/service/mechanism/TradeExecution.java b/service/src/main/java/market/guess/service/mechanism/TradeExecution.java
deleted file mode 100644
index 3d8df1d..0000000
--- a/service/src/main/java/market/guess/service/mechanism/TradeExecution.java
+++ /dev/null
@@ -1,5 +0,0 @@
-package market.guess.service.mechanism;
-
-import java.math.BigDecimal;
-
-public record TradeExecution(int filledQuantity, BigDecimal cost) {}
diff --git a/service/src/main/java/market/guess/service/mechanism/TradingMechanism.java b/service/src/main/java/market/guess/service/mechanism/TradingMechanism.java
index fc915fb..204a170 100644
--- a/service/src/main/java/market/guess/service/mechanism/TradingMechanism.java
+++ b/service/src/main/java/market/guess/service/mechanism/TradingMechanism.java
@@ -2,6 +2,7 @@ package market.guess.service.mechanism;
 
 import java.math.BigDecimal;
 import market.guess.api.MechanismType;
+import market.guess.service.domain.Trade;
 
 public sealed interface TradingMechanism permits LmsrTradingMechanism, OrderBookTradingMechanism {
 
@@ -9,7 +10,7 @@ public sealed interface TradingMechanism permits LmsrTradingMechanism, OrderBook
 
   BigDecimal openingCost();
 
-  TradeExecution buy(int optionIndex, int quantity);
+  Trade buy(int optionIndex, int quantity);
 
   BigDecimal[] prices();
 }