Fix DateTimeAgo in future

app/src/main/kotlin/org/koitharu/kotatsu/core/util/ext/Date.kt

@@ -10,13 +10,13 @@ import java.time.ZoneId
 import java.time.temporal.ChronoUnit
 import java.util.concurrent.TimeUnit
 
-fun calculateTimeAgo(instant: Instant, showMonths: Boolean = false): DateTimeAgo {
+fun calculateTimeAgo(instant: Instant, showMonths: Boolean = false): DateTimeAgo? {
-	// TODO: Use Java 9's LocalDate.ofInstant().
 	val localDate = LocalDateTime.ofInstant(instant, ZoneId.systemDefault()).toLocalDate()
 	val now = LocalDate.now()
 	val diffDays = localDate.until(now, ChronoUnit.DAYS)
 
 	return when {
+		diffDays < 0 -> null // in future, probably a bug, not supported
 		diffDays == 0L -> {
 			if (instant.until(Instant.now(), ChronoUnit.MINUTES) < 3) DateTimeAgo.JustNow
 			else DateTimeAgo.Today

app/src/main/kotlin/org/koitharu/kotatsu/download/ui/list/DownloadsViewModel.kt

@@ -225,7 +225,11 @@ class DownloadsViewModel @Inject constructor(
 				else -> {
 					val date = calculateTimeAgo(item.timestamp)
 					if (prevDate != date) {
-						destination += ListHeader(date)
+						destination += if (date != null) {
+							ListHeader(date)
+						} else {
+							ListHeader(R.string.unknown)
+						}
 					}
 					prevDate = date
 					destination += item

app/src/main/kotlin/org/koitharu/kotatsu/history/ui/HistoryListViewModel.kt

@@ -201,10 +201,14 @@ class HistoryListViewModel @Inject constructor(
 
 	private fun MangaHistory.header(order: ListSortOrder): ListHeader? = when (order) {
 		ListSortOrder.LAST_READ,
-		ListSortOrder.LONG_AGO_READ -> ListHeader(calculateTimeAgo(updatedAt))
+		ListSortOrder.LONG_AGO_READ -> calculateTimeAgo(updatedAt)?.let {
+			ListHeader(it)
+		} ?: ListHeader(R.string.unknown)
 
 		ListSortOrder.OLDEST,
-		ListSortOrder.NEWEST -> ListHeader(calculateTimeAgo(createdAt))
+		ListSortOrder.NEWEST -> calculateTimeAgo(createdAt)?.let {
+			ListHeader(it)
+		} ?: ListHeader(R.string.unknown)
 
 		ListSortOrder.UNREAD,
 		ListSortOrder.PROGRESS -> ListHeader(

app/src/main/kotlin/org/koitharu/kotatsu/tracker/ui/feed/FeedViewModel.kt

@@ -137,7 +137,11 @@ class FeedViewModel @Inject constructor(
 		for (item in this) {
 			val date = calculateTimeAgo(item.createdAt)
 			if (prevDate != date) {
-				destination += ListHeader(date)
+				destination += if (date != null) {
+					ListHeader(date)
+				} else {
+					ListHeader(R.string.unknown)
+				}
 			}
 			prevDate = date
 			destination += item.toFeedItem()