Rework updatemanager

[niklasweimann]

Special Thanks to: https://github.com/HedgehogNSK

The main purpose of this PR is to add the ability to switch between different update streams. It allows users to switch between various streams, such as long polling, webhooks, or test streams, without needing to resubscribe to a new update manager.

Core changes:

IUpdateManager extended with the Set(IObservable) method.
UpdateManager has been split into two classes: UpdateDistributor and LongPollingUpdateTracker.
UpdateDistributor serves as a facade that implements IUpdateManager.
LongPollingUpdateTracker implements IObservable.
UpdateManager is no longer needed but has been retained as is.
The TelegramBot class has been extended with a Builder that allows setting IUpdateManager and IObservable.

[HedgehogNSK]

Hi, there. 😃
Should I fix the issues that Sonar is flagging?

[niklasweimann]

@HedgehogNSK Two Issues here:

1. Could you please fix the 9 issues that sonar cloud found?
2. Cloud you please make sure that your Source Code matches the rest of the project? We use Rider for the development so when you use it too you should be able to see the issues. Otherwise please make sure your editor respects the .editorconfig of the project (I have not tested it with other IDEs but it should result in a similar style).

[HedgehogNSK]

Ок. :) I need a bit of time, and I will fix the issues. ;)

[niklasweimann]

Awesome 👍😎

[HedgehogNSK]

I have a question about src/.../Utils/Rx/ReactiveProperty.cs link to file
@niklasweimann, could you please explain what Sonar actually wants me to fix:

1. 'ReactiveProperty.Dispose()' should also call 'Dispose(true)'.:
   But my code contains the call already:

public void  Dispose()
  {
    Dispose(true);
    GC.SuppressFinalize(this);
  }

2. Modify 'ReactiveProperty.~ReactiveProperty()' so that it calls 'Dispose(false)' and then returns.
   And my code containes this implementation as well:

ReactiveProperty() => Dispose(false);

I'm confused. 😕

[niklasweimann]

Hey @HedgehogNSK,

The following implementation should meet the sonar cloud requirements:

~ReactiveProperty() => Dispose(false);

    public void Dispose()
    {
        Dispose(true);
        GC.SuppressFinalize(this);
    }

    protected virtual void Dispose(bool explicitDisposing)
    {
        if (IsDisposed)
        {
            return;
        }

        if (explicitDisposing)
        {
            OnCompleted();
            Interlocked.Exchange(ref _observers, Terminated);
        }

        IsDisposed = true;
    }

When looking at the SonarCloud issue you can click on "Why is this an issue?" and near the end is an example of how to implement disposable properly.

[sonarqubecloud]

Quality Gate passed

Issues
0 New issues
0 Accepted issues

Measures
0 Security Hotspots
11.2% Coverage on New Code
0.0% Duplication on New Code

See analysis details on SonarQube Cloud

[Copilot]

Pull Request Overview

This PR reworks the update manager system to enable switching between different update streams (long polling, webhooks, test streams) without requiring resubscription. The refactoring splits functionality into specialized components and introduces a builder pattern for flexible TelegramBot configuration.

• Introduces new IObservable<Update> implementations with custom Rx operators for update stream management
• Refactors update management into UpdateDistributor (facade) and LongPollingUpdateTracker (implementation) classes
• Adds a TelegramBot builder pattern supporting custom update managers and trackers

Reviewed Changes

Copilot reviewed 18 out of 18 changed files in this pull request and generated 5 comments.

Show a summary per file

File	Description
Utils/Rx/*.cs	Custom reactive extensions framework with observables, operators, and utility classes
TelegramBot.cs	Updated constructor to use new UpdateDistributor with LongPollingUpdateTracker
TelegramBot.Builder.cs	New builder class for configurable TelegramBot construction
UpdateDistributor.cs	New facade implementing IUpdateManager with stream switching capabilities
LongpollingUpdateTracker.cs	New IObservable implementation for long polling with setup interface
UpdateManager.cs	Added placeholder Set method to maintain interface compatibility
IUpdateManager.cs	Extended interface with Set method for tracker configuration
ITrackerSetup.cs	New interface for configuring update type filtering

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[Copilot]

The ObjectDisposedException should use the type name instead of nameof(SwitchObserver) since SwitchObserver is a nested class. Consider using GetType().Name or a constant string.

Suggested change

	throw new ObjectDisposedException(nameof(SwitchObserver));
	throw new ObjectDisposedException(GetType().Name);

[Copilot]

Setting Current to default(T) in OnError will incorrectly mark HasValue as true on line 17. This could lead to incorrect behavior where subscribers think there's a valid value after an error occurred.

Suggested change

	Current = default;
	_current = default;
	HasValue = false;

[Copilot]

After calling OnException which clears all observers, throwing the exception will not be handled by any observer. The throw statement should be removed since OnException already notifies observers of the error.

Suggested change

	throw;
	// Exception already handled by notifying observers; do not rethrow.

[Copilot]

Creating a new CancellationTokenSource without disposing the previous one can lead to resource leaks. The old token source should be disposed before creating a new one.

[Copilot]

The _trackedTypes enumerable is evaluated at construction time when all Listeners are 0, resulting in an empty collection. This should be evaluated lazily or updated when listeners change to reflect the current state.