refactoring_priority.md

Refactoring Priority

The following functions and files have been identified by our automated complexity analysis as candidates for refactoring. They currently exceed the established thresholds for cyclomatic complexity and/or function length (as configured in .eslintrc.js).

Top Complex Functions

1. mapToOnChainError in src/types/OnChainErrorCodes.ts

   • Metrics: Cyclomatic complexity of 24 (limit: 15), 125 lines (limit: 50).
   • Reason: Large switch/if-else chains mapping contract errors. Consider extracting to a mapping object or smaller helpers.

2. startSongWorker in src/workers/SongProcessorWorker.ts

   • Metrics: Cyclomatic complexity of 18 (limit: 15), 196 lines (limit: 50).
   • Reason: Heavy business logic and deeply nested async arrow functions. Extract the inner job processing logic into its own method or class.

3. finalizeUpload in src/services/SongService.ts

   • Metrics: 126 lines (limit: 50), 9 parameters (limit: 5).
   • Reason: Handles too many responsibilities (chunk merging, DB updates, queueing). Extract S3/file logic or introduce an options object for parameters.

4. Twitter OAuth Callback (router.get('/callback')) in src/routes/twitterRoutes.ts

   • Metrics: Cyclomatic complexity of 16 (limit: 15), 100 lines (limit: 50).
   • Reason: Mixes API requests, database queries, and session management. Extract Twitter API calls and user linking logic to a dedicated service.

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Note: This list is intended to guide future tech debt sprints. New code should adhere to the complexity limits enforced by CI.