OBv2: Implement Event Heap

openbook/src/main/java/com/mmorrell/openbook/model/OpenBookAnyEvent.java

@@ -0,0 +1,24 @@
+package com.mmorrell.openbook.model;
+
+import lombok.Builder;
+import lombok.Data;
+
+import java.util.Arrays;
+
+@Data
+@Builder
+public class OpenBookAnyEvent {
+
+    public static final int SIZE = 144;
+
+    // 0 = fill, 1 = out
+    private byte eventType;
+    private byte[] padding;
+
+    public static OpenBookAnyEvent readOpenBookAnyEvent(byte[] data) {
+        return OpenBookAnyEvent.builder()
+                .eventType(data[0])
+                .padding(Arrays.copyOfRange(data, 1, SIZE))
+                .build();
+    }
+}

openbook/src/main/java/com/mmorrell/openbook/model/OpenBookEventHeap.java

@@ -6,10 +6,20 @@
 import org.bitcoinj.core.Utils;
 import org.p2p.solanaj.utils.ByteUtils;
 
+import java.util.Arrays;
+import java.util.List;
+
 @Data
 @Builder
 public class OpenBookEventHeap {
 
+    private static final int FREE_HEAD_OFFSET = 8;
+    private static final int USED_HEAD_OFFSET = 10;
+    private static final int COUNT_OFFSET = 12;
+    private static final int PADDING_OFFSET = 14;
+    private static final int SEQ_NUM_OFFSET = 16;
+    private static final int EVENT_NODES_OFFSET = 24;
+
     // EventHeapHeader x 1
     private short freeHead;
     private short usedHead;
@@ -18,16 +28,27 @@ public class OpenBookEventHeap {
     private long seqNum;
 
     // + EventNode x 600 (starts at offset 24)
+    private static final int NUM_EVENT_NODES = 600;
+    private List<OpenBookEventNode> eventNodes;
 
     // + 64 bytes reserved
 
     public static OpenBookEventHeap readOpenBookEventHeap(byte[] data) {
         return OpenBookEventHeap.builder()
-                .freeHead((short) Utils.readUint16(data, 8))
-                .usedHead((short) Utils.readUint16(data, 10))
-                .count((short) Utils.readUint16(data, 12))
-                .padding((short) Utils.readUint16(data, 14))
-                .seqNum(ByteUtils.readUint64(data, 16).longValue())
+                .freeHead((short) Utils.readUint16(data, FREE_HEAD_OFFSET))
+                .usedHead((short) Utils.readUint16(data, USED_HEAD_OFFSET))
+                .count((short) Utils.readUint16(data, COUNT_OFFSET))
+                .padding((short) Utils.readUint16(data, PADDING_OFFSET))
+                .seqNum(ByteUtils.readUint64(data, SEQ_NUM_OFFSET).longValue())
+                .eventNodes(
+                        OpenBookEventNode.readEventNodes(
+                                Arrays.copyOfRange(
+                                        data,
+                                        EVENT_NODES_OFFSET,
+                                        EVENT_NODES_OFFSET + (NUM_EVENT_NODES * OpenBookEventNode.SIZE)
+                                )
+                        )
+                )
                 .build();
     }
 }

openbook/src/main/java/com/mmorrell/openbook/model/OpenBookEventNode.java

@@ -0,0 +1,52 @@
+package com.mmorrell.openbook.model;
+
+import lombok.Builder;
+import lombok.Data;
+
+import java.nio.ByteBuffer;
+import java.util.ArrayList;
+import java.util.Arrays;
+import java.util.List;
+
+@Data
+@Builder
+public class OpenBookEventNode {
+
+    // 2 shorts = 4 bytes
+    // 4 bytes of padding
+    // AnyEvent x 1 = 144 bytes
+    // 152 bytes total
+
+    public static final int SIZE = 2 + 2 + 4 + OpenBookAnyEvent.SIZE;
+    private static final int NEXT_OFFSET = 0;
+    private static final int PREV_OFFSET = 2;
+    private static final int EVENT_OFFSET = 8;
+
+    private short next;
+    private short prev;
+    private OpenBookAnyEvent event;
+
+    public static List<OpenBookEventNode> readEventNodes(byte[] bytes) {
+        List<OpenBookEventNode> results = new ArrayList<>();
+        int numNodes = bytes.length / SIZE;
+        for (int i = 0; i < numNodes; i++) {
+            byte[] nodeBytes = Arrays.copyOfRange(bytes, i * SIZE, (i + 1) * SIZE);
+            OpenBookEventNode node = OpenBookEventNode.builder()
+                    .next(ByteBuffer.wrap(nodeBytes, NEXT_OFFSET, 2).getShort())
+                    .prev(ByteBuffer.wrap(nodeBytes, PREV_OFFSET, 2).getShort())
+                    .event(
+                            OpenBookAnyEvent.readOpenBookAnyEvent(
+                                    Arrays.copyOfRange(
+                                            nodeBytes,
+                                            EVENT_OFFSET,
+                                            nodeBytes.length
+                                    )
+                            )
+                    )
+                    .build();
+            results.add(node);
+        }
+
+        return results;
+    }
+}

openbook/src/test/java/OpenBookTest.java

@@ -3,6 +3,7 @@
 import com.mmorrell.openbook.model.BookSide;
 import com.mmorrell.openbook.model.LeafNode;
 import com.mmorrell.openbook.model.NodeTag;
+import com.mmorrell.openbook.model.OpenBookEventHeap;
 import com.mmorrell.openbook.model.OpenBookMarket;
 import com.mmorrell.openbook.program.OpenbookProgram;
 import lombok.extern.slf4j.Slf4j;
@@ -18,6 +19,7 @@
 import java.io.IOException;
 import java.util.Comparator;
 import java.util.List;
+import java.util.Optional;
 
 import static org.junit.Assert.assertFalse;
 
@@ -100,4 +102,10 @@ public void eventHeapTest() throws RpcException, IOException {
                 .getDecodedData();
         Files.write(data, new File("eventHeap.bin"));
     }
+
+    @Test
+    public void openBookEventHeapTest(){
+        Optional<OpenBookEventHeap> eventHeap = openBookManager.getEventHeap(PublicKey.valueOf("GY5HKym4yKNUpdHpBBiqLB3DHbrNKhLHDFTSLPK8AbFX"));
+        eventHeap.ifPresent(heap -> log.info("Event Heap: {}", heap));
+    }
 }