WIP

Signed-off-by: James Zuccon <zuccon@gmail.com>

packages/primitives/src/transaction-graph.ts

@@ -22,6 +22,35 @@ export class TransactionGraph {
     this.transactions.delete(txHash);
   }
 
+  removeDependentTransactions(txHash: string): string[] {
+    const removedTxids: string[] = [];
+    const toRemove: Set<string> = new Set([txHash]);
+
+    const findDependents = (id: string) => {
+      for (const [otherTxid, tx] of this.transactions) {
+        if (
+          tx
+            .getInputs()
+            .some((input) => binToHex(input.outpointTransactionHash) === id)
+        ) {
+          toRemove.add(otherTxid);
+          findDependents(otherTxid);
+        }
+      }
+    };
+
+    findDependents(txHash);
+
+    for (const id of toRemove) {
+      if (this.transactions.has(id)) {
+        this.transactions.delete(id);
+        removedTxids.push(id);
+      }
+    }
+
+    return removedTxids;
+  }
+
   getTransaction(txHash: string): Transaction | undefined {
     return this.transactions.get(txHash);
   }
@@ -122,4 +151,10 @@ export class TransactionGraph {
 
     return order;
   }
+
+  getNextTransactionToBroadcast(): Transaction | undefined {
+    // This is pretty inefficient in the sense we recompile the graph each time.
+    // But I'm not sure if that would really have much real-world performance impact.
+    return this.getBroadcastOrder()[0] ?? undefined;
+  }
 }