public IReadOnlyList <CostPeriod> Execute(
DateTime startTimeInclusive,
DateTime endTimeExclusive,
IReadOnlyList <MergedSnapshot> snapshots,
IReadOnlyList <CreatorPost> creatorPosts)
{
var result = new List <CostPeriod>();
MergedSnapshot lastSnapshot = null;
foreach (var snapshot in snapshots.Concat(new List <MergedSnapshot> {
null
}))
{
if (lastSnapshot != null)
{
var cost = this.costCalculator.Execute(lastSnapshot, creatorPosts);
if (snapshot == null)
{
var period = new CostPeriod(lastSnapshot.Timestamp, endTimeExclusive, cost);
result.Add(period);
}
else
{
var period = new CostPeriod(lastSnapshot.Timestamp, snapshot.Timestamp, cost);
result.Add(period);
}
}
lastSnapshot = snapshot;
}
return(result);
}
public IReadOnlyList <MergedSnapshot> Execute(
UserId subscriberId,
UserId creatorId,
DateTime startTimeInclusive,
IReadOnlyList <ISnapshot> snapshots)
{
if (snapshots.Count == 0)
{
return(new List <MergedSnapshot>());
}
DateTime initialTimestamp = startTimeInclusive;
var firstTimestamp = snapshots[0].Timestamp;
if (firstTimestamp < startTimeInclusive)
{
initialTimestamp = firstTimestamp;
}
var creatorChannels = CreatorChannelsSnapshot.Default(initialTimestamp, creatorId);
var creatorFreeAccessUsers = CreatorFreeAccessUsersSnapshot.Default(initialTimestamp, creatorId);
var subscriberChannels = SubscriberChannelsSnapshot.Default(initialTimestamp, subscriberId);
var subscriber = SubscriberSnapshot.Default(initialTimestamp, subscriberId);
var calculatedAccountBalance = CalculatedAccountBalanceSnapshot.Default(initialTimestamp, subscriberId, LedgerAccountType.FifthweekCredit);
var mergedSnapshots = new List <MergedSnapshot>();
if (firstTimestamp > initialTimestamp)
{
mergedSnapshots.Add(new MergedSnapshot(creatorChannels, creatorFreeAccessUsers, subscriberChannels, subscriber, calculatedAccountBalance));
}
foreach (var snapshot in snapshots)
{
var assigned = this.TryAssign(snapshot, ref creatorChannels) ||
this.TryAssign(snapshot, ref creatorFreeAccessUsers) ||
this.TryAssign(snapshot, ref subscriberChannels) ||
this.TryAssign(snapshot, ref subscriber) ||
this.TryAssign(snapshot, ref calculatedAccountBalance);
if (!assigned)
{
throw new InvalidOperationException("Unknown snapshot type: " + snapshot.GetType().Name);
}
var newMergedSnapshot = new MergedSnapshot(creatorChannels, creatorFreeAccessUsers, subscriberChannels, subscriber, calculatedAccountBalance);
if (mergedSnapshots.Count > 0 && mergedSnapshots.Last().Timestamp == snapshot.Timestamp)
{
mergedSnapshots.RemoveAt(mergedSnapshots.Count - 1);
}
mergedSnapshots.Add(newMergedSnapshot);
}
return(mergedSnapshots);
}
public int Execute(MergedSnapshot snapshot, IReadOnlyList <CreatorPost> creatorPosts)
{
// No subscribed channels.
if (snapshot.SubscriberChannels.SubscribedChannels.Count == 0)
{
return(0);
}
// On creator guestlist.
if (snapshot.Subscriber.Email != null &&
snapshot.CreatorFreeAccessUsers.FreeAccessUserEmails.Contains(snapshot.Subscriber.Email))
{
return(0);
}
// No money in account.
if (snapshot.CalculatedAccountBalance.Amount <= 0)
{
return(0);
}
// Get all subscribed channels...
var creatorSubscriptions
= from s in snapshot.SubscriberChannels.SubscribedChannels
let c = snapshot.CreatorChannels.CreatorChannels.FirstOrDefault(v => v.ChannelId.Equals(s.ChannelId))
where c != null
select new
{
Subscription = s,
Channel = c
};
// ...where creator has posted in the subscriber's channel billing week...
var subscriptionsWithPosts = creatorPosts == null
? creatorSubscriptions
: creatorSubscriptions.Where(
v => this.CreatorPostedInBillingWeek(
v.Subscription.SubscriptionStartDate,
v.Subscription.ChannelId,
creatorPosts));
// ...and the current price has been accepted...
var acceptedSubscriptions = subscriptionsWithPosts.Where(v => v.Subscription.AcceptedPrice >= v.Channel.Price);
// ...calculate the total price.
var totalCost = acceptedSubscriptions.Aggregate(0, (a, s) => a + s.Channel.Price);
return(totalCost);
}
public IReadOnlyList <MergedSnapshot> Execute(
DateTime startTimeInclusive,
IReadOnlyList <MergedSnapshot> snapshots)
{
if (snapshots.Count == 0 || snapshots[0].Timestamp == startTimeInclusive)
{
return(snapshots);
}
if (snapshots[0].Timestamp > startTimeInclusive)
{
throw new InvalidOperationException("Initial merged snapshot is unexpectedly ahead of start time.");
}
// If any snapshot is located at the start time, ignore everything before.
for (int i = 0; i < snapshots.Count; i++)
{
if (snapshots[i].Timestamp == startTimeInclusive)
{
return(snapshots.Skip(i).ToList());
}
}
// We have timestamps either side of the start time, so find the first one which is
// earlier, bump it to the start time, and ignore any before.
for (int i = snapshots.Count - 1; i >= 0; i--)
{
var snapshot = snapshots[i];
if (snapshot.Timestamp < startTimeInclusive)
{
var result = snapshots.Skip(i).ToList();
result[0] = new MergedSnapshot(
startTimeInclusive,
snapshot.CreatorChannels,
snapshot.CreatorFreeAccessUsers,
snapshot.SubscriberChannels,
snapshot.Subscriber,
snapshot.CalculatedAccountBalance);
return(result);
}
}
throw new InvalidOperationException("Unexpectedly did not find required timestamps for trimming.");
}
public void WhenOnlyCalculatedAccountBalanceSnapshot_ShouldReturnMergedSnapshot()
{
var calculatedAccountBalanceSnapshot = new CalculatedAccountBalanceSnapshot(Now, SubscriberId1, LedgerAccountType.FifthweekCredit, 10);
var expectedResult = new MergedSnapshot(
Now,
CreatorChannelsSnapshot.Default(Now, CreatorId1),
CreatorFreeAccessUsersSnapshot.Default(Now, CreatorId1),
SubscriberChannelsSnapshot.Default(Now, SubscriberId1),
SubscriberSnapshot.Default(Now, SubscriberId1),
calculatedAccountBalanceSnapshot);
var result = this.target.Execute(SubscriberId1, CreatorId1, Now, new List <ISnapshot> {
calculatedAccountBalanceSnapshot
});
CollectionAssert.AreEqual(new List <MergedSnapshot> {
expectedResult
}, result.ToList());
}
public void WhenOnlySubscriberChannelSnapshot_ShouldReturnMergedSnapshot()
{
var subscriberChannelSnapshot = new SubscriberChannelsSnapshot(Now, SubscriberId1, new List <SubscriberChannelsSnapshotItem> {
new SubscriberChannelsSnapshotItem(new ChannelId(Guid.NewGuid()), 100, Now)
});
var expectedResult = new MergedSnapshot(
Now,
CreatorChannelsSnapshot.Default(Now, CreatorId1),
CreatorFreeAccessUsersSnapshot.Default(Now, CreatorId1),
subscriberChannelSnapshot,
SubscriberSnapshot.Default(Now, SubscriberId1),
CalculatedAccountBalanceSnapshot.Default(Now, SubscriberId1, LedgerAccountType.FifthweekCredit));
var result = this.target.Execute(SubscriberId1, CreatorId1, Now, new List <ISnapshot> {
subscriberChannelSnapshot
});
CollectionAssert.AreEqual(new List <MergedSnapshot> {
expectedResult
}, result.ToList());
}
/// <summary>
/// This method "rolls forward" subscriptions, which means if the user unsubscribed we
/// make sure the subscription is billed until the end of their billing period by extending
/// the subscription length here.
/// </summary>
public IReadOnlyList <MergedSnapshot> Execute(
DateTime endTimeExclusive,
IReadOnlyList <MergedSnapshot> inputSnapshots)
{
var snapshots = inputSnapshots.ToList();
var activeSubscriptions = new Dictionary <ChannelId, ActiveSubscription>();
for (int i = 0; i < snapshots.Count; i++)
{
var snapshot = snapshots[i];
foreach (var subscription in snapshot.SubscriberChannels.SubscribedChannels)
{
var billingWeekEndDateExclusive = BillingWeekUtilities.CalculateBillingWeekEndDateExclusive(
subscription.SubscriptionStartDate,
snapshot.Timestamp);
ActiveSubscription activeSubscription;
if (activeSubscriptions.TryGetValue(subscription.ChannelId, out activeSubscription))
{
// The following condition is a relaxation to allow people to briefly re-subscribe without
// trigging a whole new billing week, and therefore to reduce anticipated complaints.
// If they restarted their subscription before the minumum end date of their
// previous subscription, then we do not reset the minimum end date yet.
// However if they exceed that billing week then the new subscription's billing week will be used.
if (snapshot.Timestamp < activeSubscription.BillingWeekEndDateExclusive)
{
billingWeekEndDateExclusive = activeSubscription.BillingWeekEndDateExclusive;
}
activeSubscription = new ActiveSubscription(billingWeekEndDateExclusive, subscription);
activeSubscriptions[subscription.ChannelId] = activeSubscription;
}
else
{
activeSubscription = new ActiveSubscription(billingWeekEndDateExclusive, subscription);
activeSubscriptions.Add(subscription.ChannelId, activeSubscription);
}
}
// Copy the list so we can modify activeSubscriptions within the loop.
foreach (var activeSubscription in activeSubscriptions.Values.ToList())
{
var activeChannelId = activeSubscription.Subscription.ChannelId;
if (snapshot.SubscriberChannels.SubscribedChannels.All(v => !v.ChannelId.Equals(activeChannelId)))
{
// The subscriber has unsubscribed from this channel.
var billingWeekFinalSnapshotTime = this.GetBillingWeekFinalSnapshotTime(activeSubscription.BillingWeekEndDateExclusive);
var subscriptionDuration = snapshot.Timestamp - activeSubscription.Subscription.SubscriptionStartDate;
if (subscriptionDuration.TotalDays > DaysInWeek)
{
// We have exceeded the minimum subscripion period, so there is nothing to adjust.
activeSubscriptions.Remove(activeSubscription.Subscription.ChannelId);
}
else if (snapshot.Timestamp == billingWeekFinalSnapshotTime)
{
// We are at the end of the billing week, so there is nothing to adjust.
activeSubscriptions.Remove(activeSubscription.Subscription.ChannelId);
}
else if (snapshot.Timestamp < billingWeekFinalSnapshotTime)
{
if (snapshot.CreatorChannels.CreatorChannels.All(v => !v.ChannelId.Equals(activeChannelId)))
{
// We are within the billing week, but the channel is no longer published.
// So we stop billing at this point.
activeSubscriptions.Remove(activeSubscription.Subscription.ChannelId);
}
else
{
// We are still within their billing week and the creator still publishes the channel.
// We must extend their subscription to this snapshot.
var newSnapshot = new MergedSnapshot(
snapshot.Timestamp,
snapshot.CreatorChannels,
snapshot.CreatorFreeAccessUsers,
new SubscriberChannelsSnapshot(
snapshot.SubscriberChannels.Timestamp,
snapshot.SubscriberChannels.SubscriberId,
snapshot.SubscriberChannels.SubscribedChannels.Concat(new[] { activeSubscription.Subscription }).ToList()),
snapshot.Subscriber,
snapshot.CalculatedAccountBalance);
snapshots[i] = newSnapshot;
if ((i == snapshots.Count - 1 && activeSubscription.BillingWeekEndDateExclusive < endTimeExclusive) ||
(i < snapshots.Count - 1 && snapshots[i + 1].Timestamp > billingWeekFinalSnapshotTime))
{
// Either this is the last snapshot and the billing week ends before the end date of
// our search range, or the next snapshot will be in the next billing week.
// Either way, we need to insert a snapshot to end the biling at the correct time.
var endSnapshot = new MergedSnapshot(
billingWeekFinalSnapshotTime,
snapshot.CreatorChannels,
snapshot.CreatorFreeAccessUsers,
snapshot.SubscriberChannels,
snapshot.Subscriber,
snapshot.CalculatedAccountBalance);
snapshots.Insert(i + 1, endSnapshot);
}
snapshot = snapshots[i];
}
}
}
}
}
return(snapshots);
}
