/*
* Copyright 2010-2013 Ning, Inc.
*
* Ning licenses this file to you under the Apache License, version 2.0
* (the "License"); you may not use this file except in compliance with the
* License. You may obtain a copy of the License at:
*
* http://www.apache.org/licenses/LICENSE-2.0
*
* Unless required by applicable law or agreed to in writing, software
* distributed under the License is distributed on an "AS IS" BASIS, WITHOUT
* WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. See the
* License for the specific language governing permissions and limitations
* under the License.
*/
package com.ning.billing.invoice.generator;
import java.math.BigDecimal;
import java.util.ArrayList;
import java.util.Collection;
import java.util.HashMap;
import java.util.Iterator;
import java.util.List;
import java.util.Map;
import java.util.UUID;
import javax.annotation.Nullable;
import org.joda.time.LocalDate;
import org.joda.time.Months;
import org.slf4j.Logger;
import org.slf4j.LoggerFactory;
import com.ning.billing.ErrorCode;
import com.ning.billing.catalog.api.BillingPeriod;
import com.ning.billing.catalog.api.Currency;
import com.ning.billing.invoice.api.Invoice;
import com.ning.billing.invoice.api.InvoiceApiException;
import com.ning.billing.invoice.api.InvoiceItem;
import com.ning.billing.invoice.api.InvoiceItemType;
import com.ning.billing.invoice.model.BillingMode;
import com.ning.billing.invoice.model.CreditBalanceAdjInvoiceItem;
import com.ning.billing.invoice.model.DefaultInvoice;
import com.ning.billing.invoice.model.FixedPriceInvoiceItem;
import com.ning.billing.invoice.model.InAdvanceBillingMode;
import com.ning.billing.invoice.model.InvalidDateSequenceException;
import com.ning.billing.invoice.model.InvoicingConfiguration;
import com.ning.billing.invoice.model.RecurringInvoiceItem;
import com.ning.billing.invoice.model.RecurringInvoiceItemData;
import com.ning.billing.invoice.model.RepairAdjInvoiceItem;
import com.ning.billing.util.clock.Clock;
import com.ning.billing.util.config.InvoiceConfig;
import com.ning.billing.util.svcapi.junction.BillingEvent;
import com.ning.billing.util.svcapi.junction.BillingEventSet;
import com.ning.billing.util.svcapi.junction.BillingModeType;
import com.google.common.base.Predicate;
import com.google.common.collect.Collections2;
import com.google.inject.Inject;
public class DefaultInvoiceGenerator implements InvoiceGenerator {
private static final Logger log = LoggerFactory.getLogger(DefaultInvoiceGenerator.class);
private static final int ROUNDING_MODE = InvoicingConfiguration.getRoundingMode();
private static final int NUMBER_OF_DECIMALS = InvoicingConfiguration.getNumberOfDecimals();
private final Clock clock;
private final InvoiceConfig config;
@Inject
public DefaultInvoiceGenerator(final Clock clock, final InvoiceConfig config) {
this.clock = clock;
this.config = config;
}
/*
* adjusts target date to the maximum invoice target date, if future invoices exist
*/
@Override
public Invoice generateInvoice(final UUID accountId, @Nullable final BillingEventSet events,
@Nullable final List<Invoice> existingInvoices,
final LocalDate targetDate,
final Currency targetCurrency) throws InvoiceApiException {
if ((events == null) || (events.size() == 0) || events.isAccountAutoInvoiceOff()) {
return null;
}
validateTargetDate(targetDate);
final List<InvoiceItem> existingItems = new ArrayList<InvoiceItem>();
if (existingInvoices != null) {
for (final Invoice invoice : existingInvoices) {
for (final InvoiceItem item : invoice.getInvoiceItems()) {
if (item.getSubscriptionId() == null || // Always include migration invoices, credits, external charges etc.
!events.getSubscriptionIdsWithAutoInvoiceOff()
.contains(item.getSubscriptionId())) { //don't add items with auto_invoice_off tag
existingItems.add(item);
}
}
}
}
final LocalDate adjustedTargetDate = adjustTargetDate(existingInvoices, targetDate);
final Invoice invoice = new DefaultInvoice(accountId, clock.getUTCToday(), adjustedTargetDate, targetCurrency);
final UUID invoiceId = invoice.getId();
// Generate list of proposed invoice items based on billing events from junction-- proposed items are ALL items since beginning of time
final List<InvoiceItem> proposedItems = generateInvoiceItems(invoiceId, accountId, events, adjustedTargetDate, targetCurrency);
// Remove repaired and repair items -- since they never change and can't be regenerated
removeRepairedAndRepairInvoiceItems(existingItems);
// Remove from both lists the items in common
removeMatchingInvoiceItems(proposedItems, existingItems);
// Add repair items based on what is left in existing items
addRepairItems(existingItems, proposedItems);
// Go through each invoice and if balance is negative, generate CBA of opposite amount -- which could happen if there was some repair
// TODO Should this be merged with existing CBA logic in the dao layer ?
generateCBAForExistingInvoices(accountId, existingInvoices, proposedItems, targetCurrency);
consumeExistingCredit(invoiceId, accountId, existingItems, proposedItems, targetCurrency);
// Finally add thos new items on the new invoice
invoice.addInvoiceItems(proposedItems);
return proposedItems.size() != 0 ? invoice : null;
}
void generateCBAForExistingInvoices(final UUID accountId, final List<Invoice> existingInvoices,
final List<InvoiceItem> proposedItems, final Currency currency) {
// Determine most accurate invoice balances up to this point
final Map<UUID, BigDecimal> amountOwedByInvoice = new HashMap<UUID, BigDecimal>();
if (existingInvoices != null) {
for (final Invoice invoice : existingInvoices) {
amountOwedByInvoice.put(invoice.getId(), invoice.getBalance());
}
}
for (final InvoiceItem item : proposedItems) {
final UUID invoiceId = item.getInvoiceId();
if (amountOwedByInvoice.containsKey(invoiceId)) {
amountOwedByInvoice.put(invoiceId, amountOwedByInvoice.get(invoiceId).add(item.getAmount()));
} else {
amountOwedByInvoice.put(invoiceId, item.getAmount());
}
}
for (final UUID invoiceId : amountOwedByInvoice.keySet()) {
final BigDecimal invoiceBalance = amountOwedByInvoice.get(invoiceId);
if (invoiceBalance.compareTo(BigDecimal.ZERO) < 0) {
final LocalDate creditDate = clock.getUTCToday();
final CreditBalanceAdjInvoiceItem creditInvoiceItem = new CreditBalanceAdjInvoiceItem(invoiceId, accountId, creditDate, invoiceBalance.negate(), currency);
proposedItems.add(creditInvoiceItem);
}
}
}
/**
* At this point either we have 0 existingItem left or those left need to be repaired
*
* @param existingItems the list of remaining existing items
* @param proposedItems the list of remaining proposed items
*/
void addRepairItems(final List<InvoiceItem> existingItems, final List<InvoiceItem> proposedItems) {
for (final InvoiceItem existingItem : existingItems) {
if (existingItem.getInvoiceItemType() == InvoiceItemType.RECURRING ||
existingItem.getInvoiceItemType() == InvoiceItemType.FIXED) {
final BigDecimal existingAdjustedPositiveAmount = getAdjustedPositiveAmount(existingItems, existingItem.getId());
final BigDecimal amountNegated = existingItem.getAmount() == null ? null : existingItem.getAmount().subtract(existingAdjustedPositiveAmount).negate();
if (amountNegated != null && amountNegated.compareTo(BigDecimal.ZERO) < 0) {
final RepairAdjInvoiceItem repairItem = new RepairAdjInvoiceItem(existingItem.getInvoiceId(), existingItem.getAccountId(), existingItem.getStartDate(), existingItem.getEndDate(), amountNegated, existingItem.getCurrency(), existingItem.getId());
proposedItems.add(repairItem);
}
}
}
}
// We check to see if there are any adjustments that point to the item we are trying to repair
// If we did any CREDIT_ADJ or REFUND_ADJ, then we unfortunately we can't know what is the intent
// was as it applies to the full Invoice, so we ignore it. That might result in an extra positive CBA
// that would have to be corrected manually. This is the best we can do, and administrators should always
// use ITEM_ADJUSTEMNT rather than CREDIT_ADJ or REFUND_ADJ when possible.
//
BigDecimal getAdjustedPositiveAmount(final List<InvoiceItem> existingItems, final UUID linkedItemId) {
BigDecimal totalAdjustedOnItem = BigDecimal.ZERO;
final Collection<InvoiceItem> invoiceItems = Collections2.filter(existingItems, new Predicate<InvoiceItem>() {
@Override
public boolean apply(final InvoiceItem item) {
return item.getInvoiceItemType() == InvoiceItemType.ITEM_ADJ &&
item.getLinkedItemId() != null && item.getLinkedItemId().equals(linkedItemId);
}
});
for (final InvoiceItem invoiceItem : invoiceItems) {
totalAdjustedOnItem = totalAdjustedOnItem.add(invoiceItem.getAmount());
}
return totalAdjustedOnItem.negate();
}
void consumeExistingCredit(final UUID invoiceId, final UUID accountId, final List<InvoiceItem> existingItems,
final List<InvoiceItem> proposedItems, final Currency targetCurrency) {
BigDecimal totalUnusedCreditAmount = BigDecimal.ZERO;
BigDecimal totalAmountOwed = BigDecimal.ZERO;
for (final InvoiceItem item : existingItems) {
if (item.getInvoiceItemType() == InvoiceItemType.CBA_ADJ) {
totalUnusedCreditAmount = totalUnusedCreditAmount.add(item.getAmount());
}
}
for (final InvoiceItem item : proposedItems) {
if (item.getInvoiceItemType() == InvoiceItemType.CBA_ADJ) {
totalUnusedCreditAmount = totalUnusedCreditAmount.add(item.getAmount());
} else if (item.getInvoiceId().equals(invoiceId)) {
totalAmountOwed = totalAmountOwed.add(item.getAmount());
}
}
BigDecimal creditAmount = BigDecimal.ZERO;
if (totalUnusedCreditAmount.compareTo(BigDecimal.ZERO) > 0) {
if (totalAmountOwed.abs().compareTo(totalUnusedCreditAmount.abs()) > 0) {
creditAmount = totalUnusedCreditAmount.negate();
} else {
creditAmount = totalAmountOwed.negate();
}
}
if (creditAmount.compareTo(BigDecimal.ZERO) < 0) {
final LocalDate creditDate = clock.getUTCToday();
final CreditBalanceAdjInvoiceItem creditInvoiceItem = new CreditBalanceAdjInvoiceItem(invoiceId, accountId, creditDate, creditAmount, targetCurrency);
proposedItems.add(creditInvoiceItem);
}
}
private void validateTargetDate(final LocalDate targetDate) throws InvoiceApiException {
final int maximumNumberOfMonths = config.getNumberOfMonthsInFuture();
if (Months.monthsBetween(clock.getUTCToday(), targetDate).getMonths() > maximumNumberOfMonths) {
throw new InvoiceApiException(ErrorCode.INVOICE_TARGET_DATE_TOO_FAR_IN_THE_FUTURE, targetDate.toString());
}
}
private LocalDate adjustTargetDate(final List<Invoice> existingInvoices, final LocalDate targetDate) {
if (existingInvoices == null) {
return targetDate;
}
LocalDate maxDate = targetDate;
for (final Invoice invoice : existingInvoices) {
if (invoice.getTargetDate().isAfter(maxDate)) {
maxDate = invoice.getTargetDate();
}
}
return maxDate;
}
/*
* Removes all matching items from both submitted collections
*/
void removeMatchingInvoiceItems(final List<InvoiceItem> proposedItems,
final List<InvoiceItem> existingInvoiceItems) {
// We can't just use sets here as order matters (we want to keep duplicated in existingInvoiceItems)
final Iterator<InvoiceItem> proposedItemIterator = proposedItems.iterator();
while (proposedItemIterator.hasNext()) {
final InvoiceItem proposedItem = proposedItemIterator.next();
final Iterator<InvoiceItem> existingItemIterator = existingInvoiceItems.iterator();
while (existingItemIterator.hasNext()) {
final InvoiceItem existingItem = existingItemIterator.next();
if (existingItem.matches(proposedItem)) {
existingItemIterator.remove();
proposedItemIterator.remove();
break;
}
}
}
}
/**
* Remove from the existing item list all repaired items-- both
* repaired and repair
*
* @param existingItems
*/
void removeRepairedAndRepairInvoiceItems(final List<InvoiceItem> existingItems) {
final List<UUID> itemsToRemove = new ArrayList<UUID>();
for (final InvoiceItem item : existingItems) {
if (item.getInvoiceItemType() == InvoiceItemType.REPAIR_ADJ) {
itemsToRemove.add(item.getId());
itemsToRemove.add(item.getLinkedItemId());
}
}
final Iterator<InvoiceItem> iterator = existingItems.iterator();
while (iterator.hasNext()) {
final InvoiceItem item = iterator.next();
if (itemsToRemove.contains(item.getId())) {
iterator.remove();
}
}
}
private List<InvoiceItem> generateInvoiceItems(final UUID invoiceId, final UUID accountId, final BillingEventSet events,
final LocalDate targetDate, final Currency currency) throws InvoiceApiException {
final List<InvoiceItem> items = new ArrayList<InvoiceItem>();
if (events.size() == 0) {
return items;
}
// Pretty-print the generated invoice items from the junction events
final StringBuilder logStringBuilder = new StringBuilder("Invoice items generated for invoiceId ")
.append(invoiceId)
.append(" and accountId ")
.append(accountId);
final Iterator<BillingEvent> eventIt = events.iterator();
BillingEvent nextEvent = eventIt.next();
while (eventIt.hasNext()) {
final BillingEvent thisEvent = nextEvent;
nextEvent = eventIt.next();
if (!events.getSubscriptionIdsWithAutoInvoiceOff().
contains(thisEvent.getSubscription().getId())) { // don't consider events for subscriptions that have auto_invoice_off
final BillingEvent adjustedNextEvent = (thisEvent.getSubscription().getId() == nextEvent.getSubscription().getId()) ? nextEvent : null;
items.addAll(processEvents(invoiceId, accountId, thisEvent, adjustedNextEvent, targetDate, currency, logStringBuilder));
}
}
items.addAll(processEvents(invoiceId, accountId, nextEvent, null, targetDate, currency, logStringBuilder));
log.info(logStringBuilder.toString());
return items;
}
// Turn a set of events into a list of invoice items. Note that the dates on the invoice items will be rounded (granularity of a day)
private List<InvoiceItem> processEvents(final UUID invoiceId, final UUID accountId, final BillingEvent thisEvent, @Nullable final BillingEvent nextEvent,
final LocalDate targetDate, final Currency currency,
final StringBuilder logStringBuilder) throws InvoiceApiException {
final List<InvoiceItem> items = new ArrayList<InvoiceItem>();
// Handle fixed price items
final InvoiceItem fixedPriceInvoiceItem = generateFixedPriceItem(invoiceId, accountId, thisEvent, targetDate, currency);
if (fixedPriceInvoiceItem != null) {
items.add(fixedPriceInvoiceItem);
}
// Handle recurring items
final BillingPeriod billingPeriod = thisEvent.getBillingPeriod();
if (billingPeriod != BillingPeriod.NO_BILLING_PERIOD) {
final BillingMode billingMode = instantiateBillingMode(thisEvent.getBillingMode());
final LocalDate startDate = new LocalDate(thisEvent.getEffectiveDate(), thisEvent.getTimeZone());
if (!startDate.isAfter(targetDate)) {
final LocalDate endDate = (nextEvent == null) ? null : new LocalDate(nextEvent.getEffectiveDate(), nextEvent.getTimeZone());
final int billCycleDayLocal = thisEvent.getBillCycleDayLocal();
final List<RecurringInvoiceItemData> itemData;
try {
itemData = billingMode.calculateInvoiceItemData(startDate, endDate, targetDate, billCycleDayLocal, billingPeriod);
} catch (InvalidDateSequenceException e) {
throw new InvoiceApiException(ErrorCode.INVOICE_INVALID_DATE_SEQUENCE, startDate, endDate, targetDate);
}
for (final RecurringInvoiceItemData itemDatum : itemData) {
final BigDecimal rate = thisEvent.getRecurringPrice();
if (rate != null) {
final BigDecimal amount = itemDatum.getNumberOfCycles().multiply(rate).setScale(NUMBER_OF_DECIMALS, ROUNDING_MODE);
final RecurringInvoiceItem recurringItem = new RecurringInvoiceItem(invoiceId,
accountId,
thisEvent.getSubscription().getBundleId(),
thisEvent.getSubscription().getId(),
thisEvent.getPlan().getName(),
thisEvent.getPlanPhase().getName(),
itemDatum.getStartDate(), itemDatum.getEndDate(),
amount, rate, currency);
items.add(recurringItem);
}
}
}
}
// For debugging purposes
logStringBuilder.append("\n")
.append(thisEvent);
for (final InvoiceItem item : items) {
logStringBuilder.append("\n\t")
.append(item);
}
return items;
}
private BillingMode instantiateBillingMode(final BillingModeType billingMode) {
switch (billingMode) {
case IN_ADVANCE:
return new InAdvanceBillingMode();
default:
throw new UnsupportedOperationException();
}
}
InvoiceItem generateFixedPriceItem(final UUID invoiceId, final UUID accountId, final BillingEvent thisEvent,
final LocalDate targetDate, final Currency currency) {
final LocalDate roundedStartDate = new LocalDate(thisEvent.getEffectiveDate(), thisEvent.getTimeZone());
if (roundedStartDate.isAfter(targetDate)) {
return null;
} else {
final BigDecimal fixedPrice = thisEvent.getFixedPrice();
if (fixedPrice != null) {
return new FixedPriceInvoiceItem(invoiceId, accountId, thisEvent.getSubscription().getBundleId(),
thisEvent.getSubscription().getId(),
thisEvent.getPlan().getName(), thisEvent.getPlanPhase().getName(),
roundedStartDate, fixedPrice, currency);
} else {
return null;
}
}
}
}