feat: implement comprehensive rewards business logic system

[Praizfotos]

📖 Rewards Business Logic - Documentation Index

🎯 Start Here

• EXECUTIVE_SUMMARY.md ← Start here for overview
• QUICK_REFERENCE.md ← Quick answers to common questions

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📚 Complete Documentation

For Project Managers & Stakeholders

1. EXECUTIVE_SUMMARY.md - High-level overview
2. IMPLEMENTATION_STATUS.md - What was delivered

For Developers

1. QUICK_REFERENCE.md - Common tasks & patterns
2. REWARDS_IMPLEMENTATION.md - Feature details & API
3. REWARDS_INTEGRATION.md - Integration examples
4. Backend test files - backend/tests/ - Usage examples

For DevOps / Database Admins

1. REWARDS_INTEGRATION.md - Deployment checklist
2. Database migration files - database/016_*.sql, database/017_*.sql
3. REWARDS_IMPLEMENTATION.md - Database schema section

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🗂️ File Structure

nova-rewards/
├── EXECUTIVE_SUMMARY.md ..................... Overview & summary
├── QUICK_REFERENCE.md ....................... Developer cheat sheet
├── REWARDS_IMPLEMENTATION.md ................ Complete feature guide
├── REWARDS_INTEGRATION.md ................... Integration examples
├── IMPLEMENTATION_STATUS.md ................. Status & checklist
│
├── novaRewards/backend/
│   ├── services/
│   │   ├── earningService.js ............... Point earning logic
│   │   ├── tierService.js ................. Tier management
│   │   ├── eligibilityService.js .......... Validation logic
│   │   └── expirationService.js ........... Point expiration
│   │
│   ├── db/
│   │   └── tierRepository.js .............. Tier database layer
│   │
│   ├── routes/
│   │   ├── rewards.js ..................... Earn endpoints (UPDATED)
│   │   └── tiers.js ....................... Tier endpoints (NEW)
│   │
│   └── tests/
│       ├── earningService.test.js ......... Earning tests
│       ├── tierService.test.js ............ Tier tests
│       ├── eligibilityService.test.js .... Eligibility tests
│       └── expirationService.test.js ..... Expiration tests
│
└── novaRewards/database/
    ├── 016_create_tiers.sql ............... Tier schema
    └── 017_add_expiration_tracking.sql .... Expiration schema

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🎓 Learning Paths

Path 1: I Want to Understand the System (15 min)

1. Read: EXECUTIVE_SUMMARY.md
2. Skim: Architecture section of REWARDS_IMPLEMENTATION.md
3. Reference: QUICK_REFERENCE.md for key concepts

Path 2: I Need to Integrate This (30 min)

1. Read: REWARDS_INTEGRATION.md - Quick Start Checklist
2. Follow: Step-by-step integration examples
3. Check: Deployment checklist

Path 3: I Need to Debug Something (10 min)

1. Reference: QUICK_REFERENCE.md - Error Codes section
2. Check: Troubleshooting section
3. Review: Relevant test file for working example

Path 4: I'm a Developer (1-2 hours)

1. Read: QUICK_REFERENCE.md
2. Study: Relevant service file
3. Review: Corresponding test file
4. Reference: REWARDS_IMPLEMENTATION.md for API details

Path 5: I'm Deploying to Production (45 min)

1. Read: REWARDS_INTEGRATION.md - Deployment section
2. Run: Database migrations
3. Check: Deployment checklist
4. Test: All test suites pass

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🔍 Finding Information

"How do I...?"

...record a point earning?
→ QUICK_REFERENCE.md "Common Tasks" OR earningService.js

...check if user can redeem?
→ QUICK_REFERENCE.md "Common Tasks" OR eligibilityService.js

...get user's tier info?
→ QUICK_REFERENCE.md "Common Tasks" OR tierService.js

...handle point expiration?
→ QUICK_REFERENCE.md "Common Tasks" OR expirationService.js

...integrate with my system?
→ REWARDS_INTEGRATION.md "Quick Start" OR "Common Integration Points"

...test the implementation?
→ REWARDS_INTEGRATION.md "Deployment Checklist" OR backend/tests/

...deploy to production?
→ REWARDS_INTEGRATION.md "Deployment Checklist"

"What is...?"

...the tier system?
→ REWARDS_IMPLEMENTATION.md "Tier System" OR QUICK_REFERENCE.md

...the point formula?
→ QUICK_REFERENCE.md "Key Concepts" OR REWARDS_IMPLEMENTATION.md "Point Earning"

...the API?
→ REWARDS_IMPLEMENTATION.md "API Endpoints"

...the database schema?
→ REWARDS_IMPLEMENTATION.md "Database Schema" OR 016/017 migration files

...the error codes?
→ QUICK_REFERENCE.md "Error Codes" OR REWARDS_INTEGRATION.md

"Why...?"

...isn't tier updating?
→ QUICK_REFERENCE.md "When to Use Each Service" OR REWARDS_INTEGRATION.md "Troubleshooting"

...is balance incorrect?
→ REWARDS_INTEGRATION.md "Troubleshooting"

...are points expiring?
→ QUICK_REFERENCE.md "Scenario 4" OR REWARDS_IMPLEMENTATION.md "Point Expiration"

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📊 Quick Stats

Metric	Count
Service Files	4
API Endpoints	8
Database Tables	2 new, 2 extended
Test Suites	4
Test Cases	60+
Documentation Pages	5
Total Lines of Code	2000+
Database Migrations	2

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✅ Implementation Checklist

Before Reading Documentation

• Understand what "reward points" means in your system
• Know the difference between earning and redeeming

After Reading EXECUTIVE_SUMMARY.md

• Understand 4-tier system exists
• Know points are auto-calculated with multipliers
• Know points expire automatically

After Reading QUICK_REFERENCE.md

• Can explain point calculation formula
• Can list the 4 tiers and their benefits
• Can describe validation gates

After Reading REWARDS_IMPLEMENTATION.md

• Understand all API endpoints
• Know database schema
• Can explain all services

After Reading REWARDS_INTEGRATION.md

• Can follow integration checklist
• Can set up database migrations
• Can handle common scenarios

Before Deploying

• All tests passing
• Migrations applied
• Routes registered
• Daily job configured
• No database errors

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🔗 Cross-References

Services Cross-Reference

earningService.js is used by:

• routes/rewards.js (POST /api/rewards/earn)
• tierService.js (auto-tier update)

tierService.js is used by:

• earningService.js (apply multiplier)
• routes/tiers.js (all tier endpoints)
• expirationService.js (tier change handling)

eligibilityService.js is used by:

• routes/rewards.js (earn validation)
• routes/redemptions.js (redemption validation)

expirationService.js is used by:

• Daily cron job (mark expired points)
• tierService.js (update on tier change)
• User dashboard (show expiration info)

Test Cross-Reference

earningService.test.js tests:

• calculatePointsEarned()
• recordPointEarning()
• getUserEarningHistory()
• getUserEarningStats()

tierService.test.js tests:

• applyTierMultiplier()
• maybeUpdateUserTier()
• getUserTierInfo()
• getTiersWithUserProgress()

eligibilityService.test.js tests:

• validateEarningEligibility()
• validateRedemptionEligibility()
• checkDailyEarningLimit()
• getRedemptionEligibilitySummary()

expirationService.test.js tests:

• markExpiredPoints()
• getExpiringPointsWarning()
• getUserExpirationStats()
• calculateActiveBalance()

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🎯 Next Steps

If You're New to the Project

1. Read EXECUTIVE_SUMMARY.md (5 min)
2. Skim QUICK_REFERENCE.md (5 min)
3. Pick a component and read its service file (10 min)
4. Look at its test file for examples (10 min)

If You Need to Integrate

1. Follow REWARDS_INTEGRATION.md "Quick Start Checklist"
2. Review "Common Integration Points"
3. Test with examples provided
4. Run test suite to verify

If You Need to Deploy

1. Follow REWARDS_INTEGRATION.md "Deployment Checklist"
2. Run all migrations
3. Register routes
4. Set up cron job
5. Run tests

If You Need to Troubleshoot

1. Check QUICK_REFERENCE.md "Error Codes"
2. Check REWARDS_INTEGRATION.md "Troubleshooting"
3. Look at relevant test file for working example
4. Review inline code comments

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📞 Documentation Support

For Reading These Docs

• Each file has a table of contents at the top
• Use Ctrl+F to search within document
• Links between documents are bolded

For Code Examples

• Check test files (backend/tests/)
• Check route handlers (routes/)
• Check service implementations

For API Reference

• See REWARDS_IMPLEMENTATION.md "API Endpoints"
• Each endpoint has request/response examples

For Database Reference

• See REWARDS_IMPLEMENTATION.md "Database Schema"
• Or run \d table_name in psql

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🏆 Documentation Quality Checklist

• Executive summary for non-technical stakeholders
• Quick reference for developers
• Complete feature documentation
• Integration guide with examples
• API documentation with request/response
• Database schema documentation
• Troubleshooting guide
• Deployment checklist
• Code examples in test files
• Inline code comments
• Error code reference
• Quick links between documents

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closes Nova-reward#350