Utilize gettxout to display spent/outspent

fixes #1088

backend/src/api/bitcoin/bitcoin-api-abstract-factory.ts

@@ -12,6 +12,7 @@ export interface AbstractBitcoinApi {
   $getAddressTransactions(address: string, lastSeenTxId: string): Promise<IEsploraApi.Transaction[]>;
   $getAddressPrefix(prefix: string): string[];
   $sendRawTransaction(rawTransaction: string): Promise<string>;
+  $getOutspends(txId: string): Promise<IEsploraApi.Outspend[]>;
 }
 export interface BitcoinRpcCredentials {
   host: string;

backend/src/api/bitcoin/bitcoin-api.ts

@@ -102,6 +102,18 @@ class BitcoinApi implements AbstractBitcoinApi {
     return this.bitcoindClient.sendRawTransaction(rawTransaction);
   }
 
+  async $getOutspends(txId: string): Promise<IEsploraApi.Outspend[]> {
+    const outSpends: IEsploraApi.Outspend[] = [];
+    const tx = await this.$getRawTransaction(txId, true, false);
+    for (let i = 0; i < tx.vout.length; i++) {
+      const txOut = await this.bitcoindClient.getTxOut(txId, i);
+      outSpends.push({
+        spent: txOut === null,
+      });
+    }
+    return outSpends;
+  }
+
   protected async $convertTransaction(transaction: IBitcoinApi.Transaction, addPrevout: boolean): Promise<IEsploraApi.Transaction> {
     let esploraTransaction: IEsploraApi.Transaction = {
       txid: transaction.txid,

backend/src/api/bitcoin/esplora-api.interface.ts

@@ -113,9 +113,9 @@ export namespace IEsploraApi {
 
   export interface Outspend {
     spent: boolean;
-    txid: string;
-    vin: number;
-    status: Status;
+    txid?: string;
+    vin?: number;
+    status?: Status;
   }
 
   export interface Asset {

backend/src/api/bitcoin/esplora-api.ts

@@ -60,6 +60,10 @@ class ElectrsApi implements AbstractBitcoinApi {
   $sendRawTransaction(rawTransaction: string): Promise<string> {
     throw new Error('Method not implemented.');
   }
+
+  $getOutspends(): Promise<IEsploraApi.Outspend[]> {
+    throw new Error('Method not implemented.');
+  }
 }
 
 export default ElectrsApi;