[Bug] Map drag state should be preserved if changed after terra-draw instantiation

[jiacona]

Describe the bug

Changes in #504 mean that the state of dragPan and dragRotate at adapter instantiation time is respected when terra-draw manages map draggability. However, if you change map draggability outside of terra-draw after the adapter is instantiated, it does not respect that updated value.

Terra Draw npm version

Using terra-draw 1.16.1 and terra-draw-maplibre-gl-adapter 1.1.1

To Reproduce

We let users change between an "edit" and "navigate" mode by controlling the state of dragPan and dragRotate on the map. We start in "navigate" mode, so at terra-draw instantiation time the map is draggable. If you change to edit mode (the map is made non-draggable), then perform any drag interaction (regardless of if it is on a terra-draw object or not), terra-draw will revert the map to being draggable.

Expected behavior

Whenever terra-draw modifies the draggability of the map during it's interactions, it should revert the map to whatever state it was in before the interaction started, not the state of the map when terra-draw was initialised.

Desktop (please complete the following information):

• OS: macOS 15.6.1
• Browser: Chrome
• Version 140.0.7339.185

Additional context

We are maintaining our own fork and I have implemented a fix for this issue here. I don't know if it is the best approach, but if you have any guidance I would be happy to put together a PR.

[JamesLMilner]

@jiacona as with #688, thanks for raising - again can see the issue at hand. Let me think on it and get back to you.

[JamesLMilner]

I was just thinking again about this today, I think the changes you suggested work on the assumption that the desired behavior is:

1. Disable the map dragging so we can handle interactions in our own library, if it is not already disabled
2. Enable them again afterwards, if map dragging was enabled when we originally disabled it

Which I think is correct, albeit potentially not explicitly implied via the API name of setDraggability. That is to say if we pass enable as true it will be ignored unless we originally disabled the map drag/pan state. I think that's probably okay since it matches the behavior we would want but also conscious it might be confusing in very specific scenarios. Going to keep thinking on it, but I think what you suggested is likely right given how we use setDraggability in Terra Draw.