# Implementation Roadmap
## Multi-Tenant Ecommerce Platform - Complete Development Guide

**Last Updated**: October 11, 2025  
**Project Status**: Slice 1 In Progress (~75% complete)

---

## 📚 Documentation Structure

Your complete vertical slice documentation is organized as follows:

```
docs/slices/
├── 00_slices_overview.md           ← Start here for overview
├── 00_implementation_roadmap.md    ← This file - your guide
├── 01_slice1_admin_vendor_foundation.md
├── 02_slice2_marketplace_import.md
├── 03_slice3_product_catalog.md
├── 04_slice4_customer_shopping.md
└── 05_slice5_order_processing.md
```

---

## 🎯 Quick Start Guide

### For Current Development (Slice 1)
1. ✅ Read `01_slice1_admin_vendor_foundation.md`
2. ✅ Review what's marked as complete vs. in-progress
3. ⏳ Focus on vendor login and dashboard pages
4. ⏳ Complete testing checklist
5. ⏳ Deploy to staging

### For Future Slices
1. Complete current slice 100%
2. Read next slice documentation
3. Set up backend (models, schemas, services, APIs)
4. Build frontend (Jinja2 templates + Alpine.js)
5. Test thoroughly
6. Move to next slice

---

## 📊 Current Status Overview

### Slice 1: Multi-Tenant Foundation (75% Complete)

#### ✅ Completed
- Backend database models (User, Vendor, Role, VendorUser)
- Authentication system (JWT, bcrypt)
- Admin service layer (vendor creation with owner)
- Admin API endpoints (CRUD, dashboard)
- Vendor context middleware (subdomain + path detection)
- Admin login page (HTML + Alpine.js)
- Admin dashboard (HTML + Alpine.js)
- Admin vendor creation page (HTML + Alpine.js)

#### ⏳ In Progress
- Vendor login page (frontend)
- Vendor dashboard page (frontend)
- Testing and debugging
- Deployment configuration

#### 📋 To Do
- Complete vendor login/dashboard
- Full testing (see Slice 1 checklist)
- Documentation updates
- Staging deployment

### Slices 2-5: Not Started

All future slices have complete documentation ready to implement.

---

## 🗓️ Development Timeline

### Week 1: Slice 1 - Foundation ⏳ CURRENT
**Days 1-3**: ✅ Backend complete  
**Days 4-5**: ⏳ Frontend completion

**Deliverable**: Admin can create vendors, vendors can log in

### Week 2: Slice 2 - Marketplace Import
**Days 1-3**: Backend (CSV import, Celery tasks, MarketplaceProduct model)  
**Days 4-5**: Frontend (import UI with Alpine.js, status tracking)

**Deliverable**: Vendors can import products from Letzshop CSV

### Week 3: Slice 3 - Product Catalog
**Days 1-3**: Backend (Product model, publishing, inventory)  
**Days 4-5**: Frontend (product management, catalog UI)

**Deliverable**: Vendors can manage product catalog

### Week 4: Slice 4 - Customer Shopping
**Days 1-3**: Backend (Customer model, Cart, public APIs)  
**Days 4-5**: Frontend (shop pages, cart with Alpine.js)

**Deliverable**: Customers can browse and shop

### Week 5: Slice 5 - Order Processing
**Days 1-3**: Backend (Order model, checkout, order management)  
**Days 4-5**: Frontend (checkout flow, order history)

**Deliverable**: Complete order workflow, platform ready for production

---

## 🎨 Technology Stack

### Backend
- **Framework**: FastAPI (Python 3.11+)
- **Database**: PostgreSQL + SQLAlchemy ORM
- **Authentication**: JWT tokens + bcrypt
- **Background Jobs**: Celery + Redis/RabbitMQ
- **API Docs**: Auto-generated OpenAPI/Swagger

### Frontend
- **Templating**: Jinja2 (server-side rendering)
- **JavaScript**: Alpine.js v3.x (15KB, CDN-based)
- **CSS**: Custom CSS with CSS variables
- **AJAX**: Fetch API (vanilla JavaScript)
- **No Build Step**: Everything runs directly in browser

### Why This Stack?
- ✅ **Alpine.js**: Lightweight reactivity without build complexity
- ✅ **Jinja2**: Server-side rendering for SEO and performance
- ✅ **No Build Step**: Faster development, easier deployment
- ✅ **FastAPI**: Modern Python, async support, auto-docs
- ✅ **PostgreSQL**: Robust, reliable, feature-rich

---

## 📋 Implementation Checklist

Use this checklist to track your progress across all slices:

### Slice 1: Foundation
- [x] Backend models created
- [x] Authentication system working
- [x] Admin service layer complete
- [x] Admin API endpoints working
- [x] Vendor context middleware working
- [x] Admin login page created
- [x] Admin dashboard created
- [x] Admin vendor creation page created
- [ ] Vendor login page created
- [ ] Vendor dashboard page created
- [ ] All tests passing
- [ ] Deployed to staging

### Slice 2: Marketplace Import
- [ ] MarketplaceProduct model
- [ ] MarketplaceImportJob model
- [ ] CSV processing service
- [ ] Celery tasks configured
- [ ] Import API endpoints
- [ ] Import UI pages
- [ ] Status tracking with Alpine.js
- [ ] All tests passing

### Slice 3: Product Catalog
- [ ] Product model complete
- [ ] Inventory model complete
- [ ] Product service layer
- [ ] Publishing logic
- [ ] Product API endpoints
- [ ] Product management UI
- [ ] Catalog browsing
- [ ] All tests passing

### Slice 4: Customer Shopping
- [ ] Customer model
- [ ] Cart model
- [ ] Customer service layer
- [ ] Cart service layer
- [ ] Public product APIs
- [ ] Shop homepage
- [ ] Product detail pages
- [ ] Shopping cart UI
- [ ] Customer registration/login
- [ ] All tests passing

### Slice 5: Order Processing
- [ ] Order model
- [ ] OrderItem model
- [ ] Order service layer
- [ ] Checkout logic
- [ ] Order API endpoints
- [ ] Checkout UI (multi-step)
- [ ] Customer order history
- [ ] Vendor order management
- [ ] Email notifications
- [ ] Payment integration (Stripe)
- [ ] All tests passing
- [ ] Production ready

---

## 🎯 Each Slice Must Include

### Backend Checklist
- [ ] Database models defined
- [ ] Pydantic schemas created
- [ ] Service layer implemented
- [ ] API endpoints created
- [ ] Exception handling added
- [ ] Database migrations applied
- [ ] Unit tests written
- [ ] Integration tests written

### Frontend Checklist
- [ ] Jinja2 templates created
- [ ] Alpine.js components implemented
- [ ] CSS styling applied
- [ ] API integration working
- [ ] Loading states added
- [ ] Error handling added
- [ ] Mobile responsive
- [ ] Browser tested (Chrome, Firefox, Safari)

### Documentation Checklist
- [ ] Slice documentation updated
- [ ] API endpoints documented
- [ ] Frontend components documented
- [ ] Testing checklist completed
- [ ] Known issues documented
- [ ] Next steps identified

---

## 🔧 Development Workflow

### Starting a New Slice

1. **Read Documentation**
   ```bash
   # Open the slice markdown file
   code docs/slices/0X_sliceX_name.md
   ```

2. **Set Up Backend**
   ```bash
   # Create database models
   # Create Pydantic schema
   # Implement service layer
   # Create API endpoints
   # Write tests
   ```

3. **Set Up Frontend**
   ```bash
   # Create Jinja2 templates
   # Add Alpine.js components
   # Style with CSS
   # Test in browser
   ```

4. **Test Thoroughly**
   ```bash
   # Run backend tests
   pytest tests/

   # Manual testing
   # Use testing checklist in slice docs
   ```

5. **Deploy & Demo**
   ```bash
   # Deploy to staging
   # Demo to stakeholders
   # Gather feedback
   ```

### Daily Development Flow

**Morning**
- Review slice documentation
- Identify today's goals (backend or frontend)
- Check testing checklist

**During Development**
- Follow code patterns from slice docs
- Use Alpine.js examples provided
- Keep vendor isolation in mind
- Test incrementally

**End of Day**
- Update slice documentation with progress
- Mark completed items in checklist
- Note any blockers or issues
- Commit code with meaningful messages

---

## 🎨 Alpine.js Patterns

### Basic Component Pattern
```javascript
function myComponent() {
    return {
        // State
        data: [],
        loading: false,
        error: null,
        
        // Lifecycle
        init() {
            this.loadData();
        },
        
        // Methods
        async loadData() {
            this.loading = true;
            try {
                this.data = await apiClient.get('/api/endpoint');
            } catch (error) {
                this.error = error.message;
            } finally {
                this.loading = false;
            }
        }
    }
}
```

### Template Usage
```html
<div x-data="myComponent()" x-init="init()">
    <div x-show="loading">Loading...</div>
    <div x-show="error" x-text="error"></div>
    <div x-show="!loading && !error">
        <template x-for="item in data" :key="item.id">
            <div x-text="item.name"></div>
        </template>
    </div>
</div>
```

### Common Directives
- `x-data` - Component state
- `x-init` - Initialization
- `x-show` - Toggle visibility
- `x-if` - Conditional rendering
- `x-for` - Loop through arrays
- `x-model` - Two-way binding
- `@click` - Event handling
- `:class` - Dynamic classes
- `x-text` - Text content
- `x-html` - HTML content

---

## 📚 Key Resources

### Documentation Files
- `00_slices_overview.md` - Complete overview
- `01_slice1_admin_vendor_foundation.md` - Current work
- `../quick_start_guide.md` - Setup guide
- `../css_structure_guide.txt` - CSS organization
- `../css_quick_reference.txt` - CSS usage
- `../12.project_readme_final.md` - Complete README

### External Resources
- [Alpine.js Documentation](https://alpinejs.dev/)
- [FastAPI Documentation](https://fastapi.tiangolo.com/)
- [Jinja2 Documentation](https://jinja.palletsprojects.com/)
- [SQLAlchemy Documentation](https://docs.sqlalchemy.org/)

---

## 🚨 Common Pitfalls to Avoid

### Backend
- ❌ Forgetting vendor isolation in queries
- ❌ Not validating vendor_id in API endpoints
- ❌ Skipping database indexes
- ❌ Not handling edge cases
- ❌ Missing error handling

### Frontend
- ❌ Not handling loading states
- ❌ Not displaying error messages
- ❌ Forgetting mobile responsiveness
- ❌ Not testing in multiple browsers
- ❌ Mixing vendor contexts

### General
- ❌ Skipping tests
- ❌ Not updating documentation
- ❌ Moving to next slice before completing current
- ❌ Not following naming conventions
- ❌ Committing without testing

---

## ✅ Quality Gates

Before moving to the next slice, ensure:

1. **All Features Complete**
   - All user stories implemented
   - All acceptance criteria met
   - All API endpoints working

2. **All Tests Pass**
   - Backend unit tests
   - Backend integration tests
   - Frontend manual testing
   - Security testing (vendor isolation)

3. **Documentation Updated**
   - Slice documentation current
   - API docs updated
   - Testing checklist completed

4. **Code Quality**
   - Follows naming conventions
   - No console errors
   - No security vulnerabilities
   - Performance acceptable

5. **Stakeholder Approval**
   - Demo completed
   - Feedback incorporated
   - Sign-off received

---

## 🎉 Success Metrics

### After Slice 1
- ✅ Admin can create vendors
- ✅ Vendors can log in
- ✅ Vendor isolation works
- ✅ Context detection works

### After Slice 2
- ✅ Vendors can import CSVs
- ✅ Background processing works
- ✅ Import tracking functional

### After Slice 3
- ✅ Products published to catalog
- ✅ Inventory management working
- ✅ Product customization enabled

### After Slice 4
- ✅ Customers can browse products
- ✅ Shopping cart functional
- ✅ Customer accounts working

### After Slice 5
- ✅ Complete checkout workflow
- ✅ Order management operational
- ✅ **Platform production-ready!**

---

## 🚀 Ready to Start?

### Current Focus: Complete Slice 1

**Your immediate next steps:**

1. ✅ Read `01_slice1_admin_vendor_foundation.md`
2. ⏳ Complete vendor login page (`templates/vendor/login.html`)
3. ⏳ Complete vendor dashboard (`templates/vendor/dashboard.html`)
4. ⏳ Test complete admin → vendor flow
5. ⏳ Check all items in Slice 1 testing checklist
6. ⏳ Deploy to staging
7. ⏳ Demo to stakeholders
8. ✅ Move to Slice 2

### Need Help?

- Check the slice documentation for detailed implementation
- Review Alpine.js examples in the docs
- Look at CSS guides for styling
- Test frequently and incrementally
- Update documentation as you progress

---

## 💡 Pro Tips

1. **Work Incrementally**: Complete one component at a time
2. **Test Continuously**: Don't wait until the end to test
3. **Follow Patterns**: Use the examples in slice documentation
4. **Document as You Go**: Update docs while code is fresh
5. **Ask for Reviews**: Get feedback early and often
6. **Celebrate Progress**: Each completed slice is a milestone!

---

## 📞 Support

If you need assistance:
- Review the slice-specific documentation
- Check the testing checklists
- Look at the example code provided
- Refer to the technology stack documentation

---

**Ready to build an amazing multi-tenant ecommerce platform?**

**Start with**: `01_slice1_admin_vendor_foundation.md`

**You've got this!** 🚀