Allow Users to Sign Up for Tournaments Without Being Signed In to the Event

[Mawiguk0]

Current Behavior
Users must be "signed in" to an event before they can sign up for tournaments. This requirement adds an extra step, which can be inconvenient during event registration when participants may want to directly enroll in tournaments.

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Proposed Feature
Introduce an optional toggle setting for tournaments, allowing users to sign up for tournaments without being signed in to the event. This toggle provides flexibility for event administrators to define whether signing into the event is mandatory for tournament signup.

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Expected Behavior

1. Default Behavior: Users must be signed into the event before signing up for a tournament (current behavior).
2. New Optional Behavior: If the toggle is enabled, users can sign up for tournaments directly, regardless of their "signed in" status.
3. The toggle should be configurable per tournament via the admin interface.

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Benefits

• Streamlines the tournament signup process, especially during high-traffic registration periods.
• Provides event organizers with more control and customization over tournament requirements.
• Reduces friction for first-time attendees or participants new to the platform.

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Considerations

1. Compatibility: Ensure views displaying users and tournaments handle cases where users are signed up for tournaments without being signed into the event.
2. Tournament Start Validation:
   • Tournaments should only start if all participants are signed into the associated event.
   • Decide whether this should require a separate toggle or if such scenarios can be handled automatically.
3. Irreversibility:
   • Once the toggle is enabled and users sign up for the tournament, the toggle should not be reversible.
   • If the toggle needs to be disabled after users have signed up, all affected users must be removed from the tournament.
4. Edge Cases: Clearly define behavior for scenarios where the toggle is switched after signups have begun.

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Implementation Plan

1. Model Update: Add a new field (e.g., allow_signup_without_signin) to the tournament model.
   • Include a database migration with a default value of false for existing tournaments.
2. Admin Interface: Add a toggle option to tournament settings in the admin panel.
3. Logic Update: Update the tournament signup logic to respect the toggle setting.
4. Testing: Test edge cases, including switching the toggle after signups have begun and starting tournaments where users are not signed into the event.
5. Documentation: Update user-facing documentation and help content to reflect the new feature.

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Next Steps

• Implement the model change and database migration.
• Update the admin interface with the new toggle setting.
• Adjust signup and validation logic for tournaments.
• Write test cases for edge scenarios and potential conflicts.
• Release updated documentation and conduct internal QA.

[Apfelwurm]

I think with the freedom to make breaking changes, we should consider if we even want to keep the Data structure there as is, or if it makes sense to built the whole participant/ticket/signing in stuff differently, but haven't thought about that much yet. Maybe thats something for the next dev meeting. Going to try to make some kind of agenda for that :)
This would then also allow to tackle #33.
Also, this issue is a duplicate of #647 , which i'm going to close for this one, since here are more specific ideas on the implementation