Refactor: adjust simulator and roster apps to adhere to Clean Architecture + added test cases for 100% coverage

[Xera-phix]

refactored backend (simulator and roster apps) to clean architecture!

refactors the simulator and roster apps to adhere to clean architecture principles. moved a large chunk of business logic out of views.py and into dedicated service layers so that views remain focused solely on http concerns.

key changes I made:

simulator app

• service layer: added run_simulation_flow to simulationservice. this handles the full orchestration (fetching players, validation, and simulation).
• views: removed the _handle_simulation_request helper. endpoints now simply call the service flow thus simplifying views.py even more

roster app

• ranking logic: created playerrankingservice to handle sorting logic (because lots of it was simply done in views before)
• view cleanup: removed redundant function-based views (players, player_detail) in favor of the existing playerviewset.
• new action: replaced standalone ranking views with a new sort_by_woba action on playerviewset.
• import logic: consolidated csv import logic into a single playerimportservice and updated management commands (there were like three separate instances of this before scattered about.

deletions & cleanup

• deleted obsolete files: roster/services/importer.py and roster/services/load_csv.py.
• removed unused and duplicate view functions.

[Copilot]

Pull request overview

This PR refactors the simulator and roster apps to follow Clean Architecture principles by moving business logic from views into dedicated service layers. The refactoring improves code organization and separation of concerns, though several issues need to be addressed.

Key Changes:

• Created SimulationService.run_simulation_flow() to orchestrate player fetching, validation, and simulation
• Introduced PlayerRankingService to encapsulate player sorting logic
• Consolidated three separate CSV import implementations into a single PlayerImportService
• Removed redundant function-based views in favor of ViewSet actions
• Cleaned up views to focus solely on HTTP concerns

Reviewed changes

Copilot reviewed 9 out of 9 changed files in this pull request and generated 6 comments.

Show a summary per file

File	Description
backend/simulator/views.py	Simplified view by delegating business logic to SimulationService; removed PlayerService import and helper function
backend/simulator/services/simulation.py	Added run_simulation_flow method to orchestrate the full simulation pipeline including player fetching
backend/roster/views.py	Removed redundant function-based views; added sort_by_woba as ViewSet action
backend/roster/urls.py	Removed standalone sort-by-woba URL pattern (now handled by ViewSet router)
backend/roster/services/player_ranking.py	Added PlayerRankingService class; removed duplicate get_all_players_with_stats function
backend/roster/services/player_import.py	New consolidated service replacing importer.py and load_csv.py
backend/roster/services/load_csv.py	Deleted obsolete CSV import implementation
backend/roster/services/importer.py	Deleted obsolete CSV import implementation
backend/roster/management/commands/import_test_data.py	Updated to use new PlayerImportService

Comments suppressed due to low confidence (1)

backend/roster/services/player_import.py:4

• Import of 'Tuple' is not used.

from typing import Any, Dict, List, Optional, Tuple

---

💡 Add Copilot custom instructions for smarter, more guided reviews. Learn how to get started.

[IlyaK27]

Good changes Luke! Thanks for implementing what we talked about on call.