wallet-core: compute residual amount for recoup properly

packages/taler-util/src/backup-types.ts

@@ -534,6 +534,8 @@ export interface BackupRefreshCoinSource {
    * Public key of the coin that was refreshed into this coin.
    */
   old_coin_pub: string;
+
+  refresh_group_id: string;
 }
 
 /**

packages/taler-wallet-cli/src/integrationtests/test-revocation.ts

@@ -181,6 +181,7 @@ export async function runRevocationTest(t: GlobalTestState) {
   await makeTestPayment(t, { wallet, merchant, order });
 
   wallet.deleteDatabase();
+
   await withdrawViaBank(t, { wallet, bank, exchange, amount: "TESTKUDOS:15" });
 
   const coinDump = await wallet.client.call(WalletApiOperation.DumpCoins, {});

packages/taler-wallet-core/src/db.ts

@@ -640,6 +640,7 @@ export interface WithdrawCoinSource {
 
 export interface RefreshCoinSource {
   type: CoinSourceType.Refresh;
+  refreshGroupId: string;
   oldCoinPub: string;
 }
 

packages/taler-wallet-core/src/operations/backup/export.ts

@@ -240,6 +240,7 @@ export async function exportBackup(
             bcs = {
               type: BackupCoinSourceType.Refresh,
               old_coin_pub: coin.coinSource.oldCoinPub,
+              refresh_group_id: coin.coinSource.refreshGroupId,
             };
             break;
           case CoinSourceType.Tip:

packages/taler-wallet-core/src/operations/backup/import.ts

@@ -250,6 +250,7 @@ export async function importCoin(
         coinSource = {
           type: CoinSourceType.Refresh,
           oldCoinPub: backupCoin.coin_source.old_coin_pub,
+          refreshGroupId: backupCoin.coin_source.refresh_group_id,
         };
         break;
       case BackupCoinSourceType.Tip:

packages/taler-wallet-core/src/operations/recoup.ts

@@ -279,11 +279,21 @@ async function recoupRefreshCoin(
       checkDbInvariant(!!oldCoinDenom);
       checkDbInvariant(!!revokedCoinDenom);
       revokedCoin.status = CoinStatus.Dormant;
-      recoupGroup.scheduleRefreshCoins.push({
-        coinPub: oldCoin.coinPub,
-        //amount: Amounts.sub(oldCoinDenom.value, revokedCoinDenom.value).amount,
-        amount: revokedCoinDenom.value,
-      });
+      if (!revokedCoin.spendAllocation) {
+        // We don't know what happened to this coin
+        logger.error(
+          `can't refresh-recoup coin ${revokedCoin.coinPub}, no spendAllocation known`,
+        );
+      } else {
+        let residualAmount = Amounts.sub(
+          revokedCoinDenom.value,
+          revokedCoin.spendAllocation.amount,
+        ).amount;
+        recoupGroup.scheduleRefreshCoins.push({
+          coinPub: oldCoin.coinPub,
+          amount: residualAmount,
+        });
+      }
       await tx.coins.put(revokedCoin);
       await tx.coins.put(oldCoin);
       await putGroupAsFinished(ws, tx, recoupGroup, coinIdx);

packages/taler-wallet-core/src/operations/refresh.ts

@@ -687,6 +687,7 @@ async function refreshReveal(
         status: CoinStatus.Fresh,
         coinSource: {
           type: CoinSourceType.Refresh,
+          refreshGroupId,
           oldCoinPub: refreshGroup.oldCoinPubs[coinIndex],
         },
         coinEvHash: pc.coinEvHash,
@@ -838,10 +839,6 @@ async function processRefreshSession(
  * Refreshes the remaining amount on the coin, effectively capturing the remaining
  * value in the refresh group.
  *
- * The caller must ensure that
- * the remaining amount was updated correctly before the coin was deposited or
- * credited.
- *
  * The caller must also ensure that the coins that should be refreshed exist
  * in the current database transaction.
  */
@@ -893,6 +890,10 @@ export async function createRefreshGroup(
     );
     switch (coin.status) {
       case CoinStatus.Dormant:
+        coin.spendAllocation = {
+          amount: Amounts.stringify(ocp.amount),
+          id: `txn:refresh:${refreshGroupId}`,
+        };
         break;
       case CoinStatus.Fresh: {
         coin.status = CoinStatus.Dormant;
@@ -911,6 +912,10 @@ export async function createRefreshGroup(
         // For suspended coins, we don't have to adjust coin
         // availability, as they are not counted as available.
         coin.status = CoinStatus.Dormant;
+        coin.spendAllocation = {
+          amount: Amounts.stringify(ocp.amount),
+          id: `txn:refresh:${refreshGroupId}`,
+        };
         break;
       }
       default: