Enhance tender estimated value resolution and add unit tests

- Updated the `ResolvedEstimatedValueAndCurrency` method to aggregate procurement lot values when the tender-level estimated value is not set, improving accuracy in value retrieval.
- Introduced the `AggregateProcurementLotEstimatedValue` function to sum estimated values from procurement lots and return the first found currency.
- Modified the `ToResponseWithLanguage` method to utilize the new estimated value resolution logic.
- Added unit tests for the new functionality, ensuring correct behavior for various scenarios in the `entity_test.go` and `budget_test.go` files.

This update improves the handling of estimated values in tenders, enhancing the overall reliability of the tender management system.

ted/mapper.go

@@ -30,11 +30,11 @@ func mapProcurementLotFromTED(lot *ProcurementProjectLot) notice.ProcurementLot
 		}
 	}
 	if pp.RequestedTenderTotal != nil {
-		a := pp.RequestedTenderTotal.EstimatedOverallContractAmount
-		if v, ok := ParseEuropeanAmount(a.Text); ok {
+		amount, currencyID := pp.RequestedTenderTotal.AmountAndCurrency()
+		if v, ok := ParseEuropeanAmount(amount); ok {
 			out.EstimatedValue = v
 		}
-		out.Currency = a.CurrencyID
+		out.Currency = currencyID
 	}
 	if pp.PlannedPeriod != nil && pp.PlannedPeriod.DurationMeasure != nil {
 		dm := pp.PlannedPeriod.DurationMeasure
@@ -167,6 +167,7 @@ func (s *TEDScraper) mapPriorInformationNoticeToTender(pin *PriorInformationNoti
 	for i := range pin.ProcurementProjectLot {
 		t.ProcurementLots = append(t.ProcurementLots, mapProcurementLotFromTED(&pin.ProcurementProjectLot[i]))
 	}
+	backfillNoticeEstimatedValueFromLots(t)
 
 	if duration, unit := pin.GetDuration(); duration != "" {
 		t.Duration = duration
@@ -351,6 +352,7 @@ func (s *TEDScraper) mapToTender(cn *ContractNotice, sourceFileURL, sourceFileNa
 	for i := range cn.ProcurementProjectLots {
 		t.ProcurementLots = append(t.ProcurementLots, mapProcurementLotFromTED(&cn.ProcurementProjectLots[i]))
 	}
+	backfillNoticeEstimatedValueFromLots(t)
 
 	// Set duration information
 	if duration, unit := cn.GetDuration(); duration != "" {
@@ -506,6 +508,7 @@ func (s *TEDScraper) mapContractAwardNoticeToTender(can *ContractAwardNotice, so
 	for i := range can.ProcurementProjectLot {
 		t.ProcurementLots = append(t.ProcurementLots, mapProcurementLotFromTED(&can.ProcurementProjectLot[i]))
 	}
+	backfillNoticeEstimatedValueFromLots(t)
 
 	// Set location information from main procurement project or first lot
 	var realizedAddr *Address
@@ -663,3 +666,27 @@ func (s *TEDScraper) mapOrganization(tedOrg *Organization, role string) *notice.
 
 	return org
 }
+
+func backfillNoticeEstimatedValueFromLots(t *notice.Notice) {
+	if t == nil || t.EstimatedValue > 0 {
+		return
+	}
+	var total float64
+	var currency string
+	for _, lot := range t.ProcurementLots {
+		if lot.EstimatedValue <= 0 {
+			continue
+		}
+		total += lot.EstimatedValue
+		if currency == "" {
+			currency = strings.TrimSpace(lot.Currency)
+		}
+	}
+	if total <= 0 {
+		return
+	}
+	t.EstimatedValue = total
+	if strings.TrimSpace(t.Currency) == "" {
+		t.Currency = currency
+	}
+}