Previously when inheriting category auto-close settings for a topic, those settings were disrupted if another topic timer was assigned or if a topic was closed then manually re-opened.
This PR makes it so that when a topic is manually re-opened the topic auto-close settings are inherited from the category. However, they will now be based on the topic created_at date. As an example, for a topic with a category auto close hours setting of 72 (3 days):
* Topic was created on 2021-02-15 08:00
* Topic was closed on 2021-02-16 10:00
* Topic was opened again on 2021-02-17 06:00
Now, the topic will inherit the auto close timer again and will close automatically at **2021-02-18 08:00**, which is based on the creation date. If the current date and time is greater than the original auto-close time (e.g. we were at 2021-02-20 13:45) then no auto-close timer is created.
Note, this will not happen if the topic category auto-close setting is "based on last post".
Updating a topic's visibility did not increase or decrease the
topic_count of a category, but Category.update_stats does ignore
unlisted topics which resulted in inconsistencies when deleting
such topics.
This PR allows entering a float value for topic timers e.g. 0.5 for 30 minutes when entering hours, 0.5 for 12 hours when entering days. This is achieved by adding a new column to store the duration of a topic timer in minutes instead of the ambiguous both hours and days that it could be before.
This PR has ommitted the post migration to delete the duration column in topic timers; it will be done in a subsequent PR to ensure that no data is lost if the UPDATE query to set duration_mintues fails.
I have to keep the old keyword of duration in set_or_create_topic_timer for backwards compat, will remove at a later date after plugins are updated.
Splits the `ToggleTopicClosed` job into two distinct `OpenTopic` and `CloseTopic` jobs to make the code clearer. The old job cannot be deleted yet because of outstanding sidekiq schedules, so a todo has been added to do so later this year.
Also replaced mentions of `topic_status_update` with `topic_timer` in some files, because the `topic_status_update` model is obsolete and replaced by topic timer.
Added some shortcut methods for checking if a topic is open/whether a user can change an open topic.
This reduces chances of errors where consumers of strings mutate inputs
and reduces memory usage of the app.
Test suite passes now, but there may be some stuff left, so we will run
a few sites on a branch prior to merging
