[2.1] Fix issue with wrong date on event creating

[dragomano]

This issue is actual only for some languages (French, Russian, etc)

Fixes #7630
Closes #7630

[albertlast]

why is an ui change needed for this issue?

[dragomano]

It's not necessary. Maybe it's because I haven't updated the fork in a while.

[Sesquipedalian]

I suspect that part of the recent attachment UI changes were accidentally merged into this PR.

[Sesquipedalian]

This won't work correctly. $context['event']['start_date_orig'] gives the start date according to the event's own time zone, whereas $context['event']['start_date'] gives the start date according to the viewing user's time zone. So if the event's internal data says that it starts at 2024-05-21 23:00:00 Europe/Dublin and user's time zone is Europe/Moscow, then $context['event']['start_date_orig'] will say 2024-05-21, but $context['event']['start_date'] will say 2024-05-22, because 2024-05-21 23:00:00 Europe/Dublin is 2024-05-22 01:00:00 Europe/Moscow.

[dragomano]

The problem is that start_date_org contains the date not in the format that you mention in the example. In the case of English, there will be no problems, but with Cyrillic dates, an error Invalid date will occur when creating an event. If you are not sure about start_date, I can use date('Y-m-d', $context['event']['start_timestamp']) in a hidden field,. Likewise for end_date_orig and end_timestamp.

1. Open "Post event" page:
   
2. Select any date via date widget - as you see, the format changes
   

Results for English

Results for Russian