Sector data store

[dalyIsaac]

This is a revised version of #859.

Overview

There is an IStore which contains Whim's state. The IStore has:

• a Dispatch method to perform updates to the state, using Transform implementations
• a Pick method to retrieve data from the state

Mutability

The IStore can only be updated via Transforms being Dispatched to it. Within the IStore, all items are immutable.

Sectors

The IStore will consist of the following sectors:

• MonitorSector
• WindowSector
• MapSector
• WorkspaceSector
• CommandSector
• RouterSector
• FilterSector

Managers will remain to facilitate plugins and native calls.

External API

Transforms and Pickers will use handles or IDs. Results will be used to return errors.

Internal API

Defaults will be preferred over nullables for IDs:

public void BobTransform(WorkspaceId id = default)
{
    id = id.OrActiveWorkspace();
}

Transition

During the transition, Whim classes like Workspace, WorkspaceManager, Monitor etc. will deprecate methods as Transforms and Pickers become available. These classes will also become immutable over time.

Threading

The IStore will be protected by a reader-writer lock - see #849

Events

Events will be triggered at the end of each transform. DoLayout will be triggered at the end of the first transform to be called, before any events are triggered.

Plan

• Create new minor release
• Store basic structure #890
• MonitorSector #893
• WindowSector #895
• MapSector #900
• WorkspaceSector #904
• Switch to static access for Pickers
• Threading
  • Remove DeferWorkspacePosManager etc.
  • Ensure that the LayoutPreviewPlugin works
• Logging in Store #914
• Docs update #978
• Deprecate managers #982
• Simplify Store API #992
• Remove internal usage of deprecated managers #987
• Investigate not using immutable data structures #988
• Remove deprecated methods #989

Potential Changes

• CommandSector
• RouterSector
• FilterSector

Questions

• Solicit thoughts on the new API.
  • I'm guessing that the older API is nicer.
  • Maintaining a frontend from the API will get old.
  • One option would be to have both, like a "beginner" and "experienced" API?
• When removing the IInternal* APIs, should there still be some sort of mockable API?