The selection logic is a bit complicated. We have image selection and pagination, both of which can be triggered using the mouse or hotkeys. We have viewer image selection and comparison image selection, which is determined by the alt key.
This change ties the room together with these behaviours:
- Changing the page using pagination buttons never changes the selection.
- Changing the selected image using arrows may change the page, if the arrow key pressed would select an image off the current page.
- `right` on the last image of the current page goes to the next page
- `down` on the last row of images goes to the next page
- `left` on the first image of the current page goes to the previous page
- `up` on the first row of images goes to the previous page
- If `alt` is held when using arrow keys, we change the page, but we only change the comparison image selection.
- When using arrow keys, if the page has changed since the last image was selected, the selection is reset to the first image on the page.
- The next/previous buttons on the image viewer do the same thing as `left` and `right` without `alt`.
- When clicking an image in the gallery:
- If no modifier keys are held, the image is exclusively selected.
- If `ctrl` or `meta` are held, the image's selection status is toggled.
- If `shift` is held, all images from the last-selected image to the image are selected. If there are no images on the current page, the selection is unchanged.
- If `alt` is held, the image is set as the compare image.
- `ctrl+a` and `meta+a` add the current page to the selection.
The logic for gallery navigation and selection is now pretty hairy. It's spread across 3 hooks, a listener, redux slice, components.
When we next make changes to this part of the app, we should consider consolidating some of the related logic. Probably most of it can go into a single listener and make it much simpler to grok.
Don't like this UI (even though I suggested it). No need to prevent the user from interacting with the search term field during fetching. Let's figure out a nicer way to present this in a followup.
If the currently selected or auto-add board is archived or deleted, we should reset them. There are some edge cases taht weren't handled in the previous implementation.
All handling of this logic is moved to the (renamed) listener.
