refactor: consolidate duplicate date-utility and repo-analytics-utili…

[harshitanagpal05]

Related Issue

Closes #2567

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Type of Change

• Refactor
• Code Quality Improvement
• Maintainability Improvement

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Summary

This PR removes duplicated helper logic across multiple Next.js API endpoints by consolidating date range calculations, commit streak processing, and repository analytics into shared utility modules.

Previously, several routes maintained their own versions of the same fetch and aggregation logic, increasing maintenance overhead and the risk of inconsistent results.

This refactor creates single sources of truth while preserving existing behavior.

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What Changed

1. Centralized Date & Streak Utilities

Created shared logic in:

src/lib/streak.ts

Added:

• fetchActiveDates

Features:

• Fetches user commit activity with pagination support
• Supports up to 10 pages of results
• Uses a 1-year lookback window
• Handles timezone conversion consistently

Refactored:

• src/app/api/metrics/streak/route.ts

  • Removed local fetchActiveDates

• src/app/api/metrics/consistency-score/route.ts

  • Removed duplicate commit history fetching

• src/app/api/metrics/weekly-summary/route.ts

  • Removed duplicate:

    • getCurrentWeekStartUtc
    • calculateCurrentStreak
    • fetchActiveDates

• src/app/api/badge/streak-shield/route.ts

  • Replaced duplicate streak fetching logic

• src/lib/public-profile-data.ts

  • Reused centralized streak utilities

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2. Shared Week Calculation Helper

Updated:

src/lib/date-utils.ts

Changes:

• Exported existing getUtcWeekStart
• Reused common UTC week calculation logic

Refactored:

• src/app/api/metrics/weekly-summary/route.ts
• src/app/api/metrics/pr-review-time/route.ts

Removed duplicate week-start implementations.

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3. Consolidated Repository Analytics

Created:

src/lib/repo-analytics-utils.ts

Added:

• fetchTopRepos

Supports:

• Custom lookback windows
• Organization inclusion/exclusion filtering
• Shared repository analytics calculations

Refactored:

• src/lib/public-profile-data.ts
• src/app/api/metrics/repo-health/route.ts
• src/app/api/metrics/repos/route.ts

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Code Quality Impact

• Reduced duplicate business logic
• Improved maintainability
• Added reusable analytics helpers
• Created consistent calculation behavior across endpoints

Changes:

• 11 files modified
• 171 additions
• 441 deletions
• Net reduction: ~270 lines

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Testing

• Existing behavior preserved
• Shared helpers reused across previous duplicate paths
• No intentional API response changes introduced

[github-actions]

GSSoC Label Checklist 🏷️

@Umbrella-io — please apply the appropriate labels before merging:

Difficulty (pick one):

• level:beginner — 20 pts
• level:intermediate — 35 pts
• level:advanced — 55 pts
• level:critical — 80 pts

Quality (optional):

• quality:clean — ×1.2 multiplier
• quality:exceptional — ×1.5 multiplier

Validation (required to score):

• gssoc:approved — counts for points
• gssoc:invalid / gssoc:spam / gssoc:ai-slop — does not score

Type labels (type:*) are auto-detected from files and title. Review and adjust if needed.
Points formula: (difficulty × quality_multiplier) + type_bonus

[Priyanshu-byte-coder]

Great refactoring work — consolidating duplicated code is exactly what we need right now. Net -270 lines is solid. A few issues to address before merge:

1. Behavioral regression in repos/route.ts (important): The old code specifically checked for HTTP 401 and threw GitHubAuthError, which the GET handler catches to return a "reconnect your account" response. The shared fetchTopRepos throws a generic Error for all non-ok responses, so 401s will no longer trigger githubAuthErrorResponse() — they'll fall through to the generic 502 handler. Please either have fetchTopRepos throw a typed error on 401, or re-check the error type in the consumer.

2. Broken .catch() pattern in repos/route.ts: The .catch() discards the original error's message and stack trace just to throw a different generic error. Either re-throw the original or remove the catch entirely.

3. stale flag in streak-shield/route.ts: The old code only set stale: true on 403 (rate limit). The new catch-all sets it for every error type. Please preserve the original behavior of only marking stale on rate-limit errors.

Fix these and this is merge-ready. The consolidation itself is well done.

[harshitanagpal05]

Hi, I’ve addressed all the requested review changes in PR #2731.

• Restored GitHubAuthError handling for 401 responses
• Removed the .catch() pattern that was losing original errors
• Restored stale: true behavior only for rate-limit errors

The branch has been updated and the original behavior is preserved. Could you please review it again whenever you get a chance?

[Priyanshu-byte-coder]

Good DRY refactoring — extracts shared fetchActiveDates to reduce duplication across streak/consistency-score routes.

[Priyanshu-byte-coder]

Approved — has merge conflicts. Please rebase on main.

[Priyanshu-byte-coder]

This has merge conflicts with main. Please rebase/resolve conflicts and make sure CI is green — then it'll get a fresh review.