+
+QString tryFormatUnixEpoch(const QString& possibleEpochDate, Qt::DateFormat dateFormat, bool useUTC)
+{
+ // Does the string resemble a Unix epoch? Parse as 64-bit time
+ qint64 secsSinceEpoch = possibleEpochDate.toLongLong();
+ if (secsSinceEpoch == 0) {
+ // Parsing either failed, or '0' was sent. No need to distinguish; either way, it's not
+ // useful as epoch.
+ // See https://doc.qt.io/qt-5/qstring.html#toLongLong
+ return possibleEpochDate;
+ }
+
+ // Time checks out, parse it
+ QDateTime date;
+#if QT_VERSION >= 0x050800
+ date.setSecsSinceEpoch(secsSinceEpoch);
+#else
+ // toSecsSinceEpoch() was added in Qt 5.8. Manually downconvert to seconds for now.
+ // See https://doc.qt.io/qt-5/qdatetime.html#toMSecsSinceEpoch
+ date.setMSecsSinceEpoch(secsSinceEpoch * 1000);
+#endif
+
+ // Return the localized date/time
+ if (useUTC) {
+ // Return UTC time
+ if (dateFormat == Qt::DateFormat::ISODate) {
+ // Replace the "T" date/time separator with " " for readability. This isn't quite the
+ // ISO 8601 spec (it specifies omitting the "T" entirely), but RFC 3339 allows this.
+ // Go with RFC 3339 for human readability that's still machine-parseable, too.
+ //
+ // Before: 2018-06-21T21:35:52Z
+ // After: 2018-06-21 21:35:52Z
+ // ..........^ (10th character)
+ //
+ // See https://en.wikipedia.org/wiki/ISO_8601#cite_note-32
+ // And https://www.ietf.org/rfc/rfc3339.txt
+ return date.toUTC().toString(dateFormat).replace(10, 1, " ");
+ }
+ else {
+ return date.toUTC().toString(dateFormat);
+ }
+ }
+ else if (dateFormat == Qt::DateFormat::ISODate) {
+ // Add in ISO local timezone information via special handling below
+ // formatDateTimeToOffsetISO() handles converting "T" to " "
+ return formatDateTimeToOffsetISO(date);
+ }
+ else {
+ // Return local time
+ return date.toString(dateFormat);
+ }
+}
+
+QString formatDateTimeToOffsetISO(const QDateTime& dateTime)
+{
+ if (!dateTime.isValid()) {
+ // Don't try to do anything with invalid date/time
+ return "formatDateTimeToISO() invalid date/time";
+ }
+
+ // Replace the "T" date/time separator with " " for readability. This isn't quite the ISO 8601
+ // spec (it specifies omitting the "T" entirely), but RFC 3339 allows this. Go with RFC 3339
+ // for human readability that's still machine-parseable, too.
+ //
+ // Before: 2018-08-22T18:43:10-05:00
+ // After: 2018-08-22 18:43:10-05:00
+ // ..........^ (10th character)
+ //
+ // See https://en.wikipedia.org/wiki/ISO_8601#cite_note-32
+ // And https://www.ietf.org/rfc/rfc3339.txt
+
+ // The expected way to get a UTC offset on ISO 8601 dates
+ // Remove the "T" date/time separator
+ return dateTime.toOffsetFromUtc(dateTime.offsetFromUtc()).toString(Qt::ISODate).replace(10, 1, " ");
+}