Holy shit this took me a while. Basically we should be treating the original image center as the scale origin rather than the scaled image center. Otherwise expanding feels unsteady.
It's not very good that you can't distingiush when we haven't loaded vs when we're certain. This shifts the burden of dealing with missing values to the caller.
* Extract function to read contentHeight later
* Remove autoscroll to bottom
We're going to implement this in the UI layer instead.
* Remove worklet from non-worklets to avoid confusion
* Rename and invert hasScrolled* variables
Their naming was too ambiguous (they used to represent "has scrolled _away_ from X"). I inverted them and clarified the naming. No functional changes.
* This should not be necessary
It's already called not just from UI thread. And it only sets shared values, which can be done from either thread.
* Make hasScrolledTo* derived values
It wasn't always correct to derive them manually because reading from .value is stale on JS thread. We could fix that by using the local variables but it makes more conceptualy sense to treat these as derived anyway.
* Reimplement autoscroll-to-bottom in UI layer
Doing it here ensures we also do it when you add an image at the end of the thread. Otherwise it's very confusing where it went.
* Use fancy ScrollView
This seems to fix ScrollView getting stuck after inserting images at the thread end on Android.
* More aggressive scroll-to-bottom
* "Fix" cursor getting stuck on Android
* Revert "Use fancy ScrollView"
This reverts commit 04e34a54e3b75f8a77de5062bff5fe6e76420bbb.
* Basic adding of posts
* Switch active post on focus
* Conditionally show plus button
* Insert posts midthread
* Track active/inactive post
* Delete posts in a thread
* Focus after deletion
* Tweak empty post detection
* Mix height for active only
* Move toolbar with post on web
* Fix footer positioning
* Post All button
* Fix reply to positioning
* Improve memoization
* Improve memoization for clearVideo
* Remove unnecessary argument
* Add some manual memoization to fix re-renders
* Scroll to bottom on add new
* Fix opacity on Android
* Add backdrop
* Fix videos
* Check alt for video too
* Clear pending publish on error
* Fork alt message by type
* Separate placeholder for next posts
* Limit hitslop to avoid clashes
Dan Abramov