Support for converting a task list into a calendar

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Is your feature request related to a problem? Please describe.

I'm currently facing a dilemma where I'd like to convert a task list into a full-blown calendar that supports events. Task Lists and Calendars appear to be different entities, yet they seem to share a common ground of both being a calendar.

Describe the solution you'd like

The primary issue in my mind is that Nextcloud does not make it clear when you're dealing with a task-only list, or a full calendar supporting tasks. Perhaps having some kind of identifying information in the respective apps would be a good first step.

Following that, being able to painlessly convert between the two entities would be ideal. If going between one or the other would result in a loss of data, then being able to export that data as an option would be welcome.

Describe alternatives you've considered

A workaround is described here, which involves exporting the calendar to an .ics file then importing it back into Nextcloud. The commenter makes a note that the CalDAV specification doesn't provide for converting between the two types of entities, and that third party applications may have an issue with this. I have to push back on that assertion, since Nextcloud is supposed to be a centralized database for maintaining our calendars, among other things. So third party apps that communicate with Nextcloud should be expected to accept a change like this, and if not, then the clientside data can be cleared and the apps resynced with Nextcloud. If the workaround is as simple as exporting and importing an ics file, then I think we can automate this in Nextcloud.

References

• [NC Community] Unable to specify destination calendar for events
• [NC Community] Transform Tasks list in calendars
• [NC Community] Convert Task Only Calendar to Full Calendar
• [Reddit] Can't add events to calendars that were created from a task list, how to fix?
• [NC Deck, unrelated?] https://github.com/nextcloud/deck/issues/2629
• https://github.com/nextcloud/calendar/issues/2627

No files, tests, or entry points are identified. Start by reviewing the linked Calendar issue #2627 and the CalDAV limitation described in the workaround; done would require clearly distinguishing task-only and full calendars and defining conversion or export behavior without unacceptable data loss.