/*
* Copyright 2014-2016 Groupon, Inc
* Copyright 2014-2016 The Billing Project, LLC
*
* The Billing Project 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 org.killbill.billing.invoice.usage;
import java.util.Collections;
import java.util.Comparator;
import java.util.HashMap;
import java.util.HashSet;
import java.util.LinkedList;
import java.util.List;
import java.util.Map;
import java.util.Set;
import java.util.UUID;
import org.joda.time.DateTime;
import org.joda.time.LocalDate;
import org.killbill.billing.callcontext.InternalTenantContext;
import org.killbill.billing.catalog.api.BillingMode;
import org.killbill.billing.catalog.api.CatalogApiException;
import org.killbill.billing.catalog.api.Usage;
import org.killbill.billing.catalog.api.UsageType;
import org.killbill.billing.invoice.api.InvoiceApiException;
import org.killbill.billing.invoice.api.InvoiceItem;
import org.killbill.billing.invoice.generator.InvoiceItemGenerator.InvoiceItemGeneratorLogger;
import org.killbill.billing.invoice.usage.ContiguousIntervalUsageInArrear.UsageInArrearItemsAndNextNotificationDate;
import org.killbill.billing.junction.BillingEvent;
import org.killbill.billing.usage.RawUsage;
import org.killbill.billing.util.config.definition.InvoiceConfig;
import org.killbill.billing.util.config.definition.InvoiceConfig.UsageDetailMode;
import com.google.common.annotations.VisibleForTesting;
import com.google.common.base.Function;
import com.google.common.base.Predicate;
import com.google.common.collect.Collections2;
import com.google.common.collect.ImmutableList;
import com.google.common.collect.ImmutableMap;
import com.google.common.collect.Iterables;
import com.google.common.collect.Lists;
import com.google.common.collect.Ordering;
/**
* There is one such class created for each subscriptionId referenced in the billingEvents.
*/
public class SubscriptionUsageInArrear {
private static final Comparator<RawUsage> RAW_USAGE_DATE_COMPARATOR = new Comparator<RawUsage>() {
@Override
public int compare(final RawUsage o1, final RawUsage o2) {
int compared = o1.getDate().compareTo(o2.getDate());
if (compared != 0) {
return compared;
} else {
compared = o1.getUnitType().compareTo(o2.getUnitType());
if (compared != 0) {
return compared;
} else {
return o1.hashCode() != o2.hashCode() ? o1.hashCode() - o2.hashCode() : 0;
}
}
}
};
private final UUID accountId;
private final UUID invoiceId;
private final List<BillingEvent> subscriptionBillingEvents;
private final LocalDate targetDate;
private final List<RawUsage> rawSubscriptionUsage;
private final LocalDate rawUsageStartDate;
private final InternalTenantContext internalTenantContext;
private final UsageDetailMode usageDetailMode;
public SubscriptionUsageInArrear(final UUID accountId,
final UUID invoiceId,
final List<BillingEvent> subscriptionBillingEvents,
final List<RawUsage> rawUsage,
final LocalDate targetDate,
final LocalDate rawUsageStartDate,
final UsageDetailMode usageDetailMode,
final InternalTenantContext internalTenantContext) {
this.accountId = accountId;
this.invoiceId = invoiceId;
this.subscriptionBillingEvents = subscriptionBillingEvents;
this.targetDate = targetDate;
this.rawUsageStartDate = rawUsageStartDate;
this.internalTenantContext = internalTenantContext;
// Extract raw usage for that subscription and sort it by date
this.rawSubscriptionUsage = Ordering.<RawUsage>from(RAW_USAGE_DATE_COMPARATOR).sortedCopy(Iterables.filter(rawUsage, new Predicate<RawUsage>() {
@Override
public boolean apply(final RawUsage input) {
return input.getSubscriptionId().equals(subscriptionBillingEvents.get(0).getSubscription().getId());
}
}));
this.usageDetailMode = usageDetailMode;
}
/**
* Based on billing events, (@code existingUsage} and targetDate, figure out what remains to be billed.
*
* @param existingUsage the existing on disk usage items.
* @throws CatalogApiException
*/
public SubscriptionUsageInArrearItemsAndNextNotificationDate computeMissingUsageInvoiceItems(final List<InvoiceItem> existingUsage, final InvoiceItemGeneratorLogger invoiceItemGeneratorLogger) throws CatalogApiException, InvoiceApiException {
final SubscriptionUsageInArrearItemsAndNextNotificationDate result = new SubscriptionUsageInArrearItemsAndNextNotificationDate();
final List<ContiguousIntervalUsageInArrear> billingEventTransitionTimePeriods = computeInArrearUsageInterval();
for (final ContiguousIntervalUsageInArrear usageInterval : billingEventTransitionTimePeriods) {
final UsageInArrearItemsAndNextNotificationDate newItemsWithDetailsAndDate = usageInterval.computeMissingItemsAndNextNotificationDate(existingUsage);
// For debugging purposes
invoiceItemGeneratorLogger.append(usageInterval, newItemsWithDetailsAndDate.getInvoiceItems());
result.addUsageInArrearItemsAndNextNotificationDate(usageInterval.getUsage().getName(), newItemsWithDetailsAndDate);
}
return result;
}
@VisibleForTesting
List<ContiguousIntervalUsageInArrear> computeInArrearUsageInterval() {
final List<ContiguousIntervalUsageInArrear> usageIntervals = Lists.newLinkedList();
final Map<UsageKey, ContiguousIntervalUsageInArrear> inFlightInArrearUsageIntervals = new HashMap<UsageKey, ContiguousIntervalUsageInArrear>();
final Set<UsageKey> allSeenUsage = new HashSet<UsageKey>();
for (final BillingEvent event : subscriptionBillingEvents) {
// Extract all in arrear /consumable usage section for that billing event.
final List<Usage> usages = findUsageInArrearUsages(event);
allSeenUsage.addAll(Collections2.transform(usages, new Function<Usage, UsageKey>() {
@Override
public UsageKey apply(final Usage input) {
return new UsageKey(input.getName(), event.getCatalogEffectiveDate());
}
}));
// All inflight usage interval are candidates to be closed unless we see that current billing event referencing the same usage section.
final Set<UsageKey> toBeClosed = new HashSet<UsageKey>(allSeenUsage);
for (final Usage usage : usages) {
final UsageKey usageKey = new UsageKey(usage.getName(), event.getCatalogEffectiveDate());
// Add inflight usage interval if non existent
ContiguousIntervalUsageInArrear existingInterval = inFlightInArrearUsageIntervals.get(usageKey);
if (existingInterval == null) {
existingInterval = usage.getUsageType() == UsageType.CAPACITY ?
new ContiguousIntervalCapacityUsageInArrear(usage, accountId, invoiceId, rawSubscriptionUsage, targetDate, rawUsageStartDate, usageDetailMode, internalTenantContext) :
new ContiguousIntervalConsumableUsageInArrear(usage, accountId, invoiceId, rawSubscriptionUsage, targetDate, rawUsageStartDate, usageDetailMode, internalTenantContext);
inFlightInArrearUsageIntervals.put(usageKey, existingInterval);
}
// Add billing event for that usage interval
existingInterval.addBillingEvent(event);
// Remove usage interval for toBeClosed set
toBeClosed.remove(usageKey);
}
// Build the usage interval that are no longer referenced
for (final UsageKey usageKey : toBeClosed) {
final ContiguousIntervalUsageInArrear interval = inFlightInArrearUsageIntervals.remove(usageKey);
if (interval != null) {
interval.addBillingEvent(event);
usageIntervals.add(interval.build(true));
}
}
}
for (final UsageKey usageKey : inFlightInArrearUsageIntervals.keySet()) {
usageIntervals.add(inFlightInArrearUsageIntervals.get(usageKey).build(false));
}
inFlightInArrearUsageIntervals.clear();
return usageIntervals;
}
private List<Usage> findUsageInArrearUsages(final BillingEvent event) {
if (event.getUsages().isEmpty()) {
return Collections.emptyList();
}
final List<Usage> result = Lists.newArrayList();
for (final Usage usage : event.getUsages()) {
if (usage.getBillingMode() != BillingMode.IN_ARREAR) {
continue;
}
result.add(usage);
}
return result;
}
public class SubscriptionUsageInArrearItemsAndNextNotificationDate {
private List<InvoiceItem> invoiceItems;
private Map<String, LocalDate> perUsageNotificationDates;
public SubscriptionUsageInArrearItemsAndNextNotificationDate() {
this.invoiceItems = null;
this.perUsageNotificationDates = null;
}
public void addUsageInArrearItemsAndNextNotificationDate(final String usageName, final UsageInArrearItemsAndNextNotificationDate input) {
if (!input.getInvoiceItems().isEmpty()) {
if (invoiceItems == null) {
invoiceItems = new LinkedList<InvoiceItem>();
}
invoiceItems.addAll(input.getInvoiceItems());
}
if (input.getNextNotificationDate() != null) {
if (perUsageNotificationDates == null) {
perUsageNotificationDates = new HashMap<String, LocalDate>();
}
perUsageNotificationDates.put(usageName, input.getNextNotificationDate());
}
}
public List<InvoiceItem> getInvoiceItems() {
return invoiceItems != null ? invoiceItems : ImmutableList.<InvoiceItem>of();
}
public Map<String, LocalDate> getPerUsageNotificationDates() {
return perUsageNotificationDates != null ? perUsageNotificationDates : ImmutableMap.<String, LocalDate>of();
}
}
private static class UsageKey {
private final String usageName;
private final DateTime catalogVersion;
public UsageKey(final String usageName, final DateTime catalogVersion) {
this.usageName = usageName;
this.catalogVersion = catalogVersion;
}
@Override
public boolean equals(final Object o) {
if (this == o) {
return true;
}
if (o == null || getClass() != o.getClass()) {
return false;
}
final UsageKey usageKey = (UsageKey) o;
if (usageName != null ? !usageName.equals(usageKey.usageName) : usageKey.usageName != null) {
return false;
}
return catalogVersion != null ? catalogVersion.compareTo(usageKey.catalogVersion) == 0 : usageKey.catalogVersion == null;
}
@Override
public int hashCode() {
int result = usageName != null ? usageName.hashCode() : 0;
result = 31 * result + (catalogVersion != null ? catalogVersion.hashCode() : 0);
return result;
}
}
}