private static long calculateFromChangelog(
DefaultIssue issue, Collection<IssueChangeDto> debtChangelog, long periodDate) {
List<FieldDiffs> debtDiffs =
from(debtChangelog)
.transform(ToFieldDiffs.INSTANCE)
.filter(HasDebtChange.INSTANCE)
.toSortedList(CHANGE_ORDERING);
FieldDiffs currentChange = issue.currentChange();
if (currentChange != null && HasDebtChange.INSTANCE.apply(currentChange)) {
debtDiffs = Lists.newArrayList(debtDiffs);
debtDiffs.add(currentChange);
}
long newDebt = issue.effortInMinutes();
for (Iterator<FieldDiffs> it = debtDiffs.iterator(); it.hasNext(); ) {
FieldDiffs diffs = it.next();
Date date = diffs.creationDate();
// TODO use longs
if (isBeforeOrEqual(date, new Date(periodDate))) {
// return new value from the change that is just before the period date
return subtract(newDebt, debtDiff(diffs).newValueLong());
}
if (!it.hasNext()) {
// return old value from the change that is just after the period date when there's no more
// element in changelog
return subtract(newDebt, debtDiff(diffs).oldValueLong());
}
}
// no changelog
return 0L;
}
@Override
public Date apply(@Nonnull FieldDiffs dto) {
return dto.creationDate();
}