# Deal Room - Architecture Specification

**Project:** Deal Room - Secure Investment Banking Document Sharing Platform
**Owner:** Misha Muskepo (michael@muskepo.com)
**Tech Lead:** James
**Architecture Pattern:** inou-portal pattern

## Executive Summary

Deal Room is a secure, invite-only document sharing platform designed for Investment Banking deal teams. It provides role-based access control, encrypted file storage, AI-powered document analysis, and comprehensive audit trails for sensitive financial transactions.

## System Architecture

### Core Principles
- **Single binary deployment** - Zero runtime dependencies
- **Data-centric design** - All entities stored as typed JSON in unified entries table
- **Security-first** - Encryption at rest, RBAC, audit logging
- **AI-enhanced** - Document analysis and embeddings for intelligent search
- **Production-grade** - Battle-tested patterns from inou-portal

### Technology Stack
- **Backend:** Go 1.22+ (single binary)
- **Templates:** templ (type-safe HTML generation)
- **Frontend:** HTMX + Tailwind CSS (CDN)
- **Database:** SQLite with encryption at rest
- **File Storage:** Encrypted (AES-256-GCM) + Compressed (zstd)
- **AI/ML:** K2.5 for document analysis and embeddings
- **Authentication:** Magic link + session cookies

## Database Schema

### Core Tables

#### users
```sql
CREATE TABLE users (
    id TEXT PRIMARY KEY,
    email TEXT UNIQUE NOT NULL,
    name TEXT NOT NULL,
    role TEXT NOT NULL CHECK (role IN ('admin', 'user')),
    avatar_url TEXT,
    created_at INTEGER NOT NULL,
    last_login INTEGER,
    is_active BOOLEAN NOT NULL DEFAULT 1
);

CREATE INDEX idx_users_email ON users(email);
CREATE INDEX idx_users_active ON users(is_active);
```

#### entries
**Unified data table storing all content types as typed JSON**
```sql
CREATE TABLE entries (
    id TEXT PRIMARY KEY,
    parent_id TEXT, -- For threading/hierarchy
    deal_room_id TEXT NOT NULL, -- Links to deal room entry
    entry_type TEXT NOT NULL CHECK (entry_type IN ('deal_room', 'document', 'note', 'message', 'analysis')),
    title TEXT NOT NULL,
    content TEXT NOT NULL, -- JSON payload, schema varies by type
    file_path TEXT, -- For documents: encrypted file path
    file_size INTEGER, -- Original file size
    file_hash TEXT, -- SHA-256 of original file
    embedding BLOB, -- AI embeddings for search
    created_by TEXT NOT NULL,
    created_at INTEGER NOT NULL,
    updated_at INTEGER NOT NULL,
    
    FOREIGN KEY (created_by) REFERENCES users(id),
    FOREIGN KEY (parent_id) REFERENCES entries(id),
    FOREIGN KEY (deal_room_id) REFERENCES entries(id)
);

CREATE INDEX idx_entries_deal_room ON entries(deal_room_id);
CREATE INDEX idx_entries_type ON entries(entry_type);
CREATE INDEX idx_entries_parent ON entries(parent_id);
CREATE INDEX idx_entries_created ON entries(created_at);
CREATE INDEX idx_entries_creator ON entries(created_by);
```

#### access
**RBAC permissions using bitmask**
```sql
CREATE TABLE access (
    id TEXT PRIMARY KEY,
    entry_id TEXT NOT NULL,
    user_id TEXT NOT NULL,
    permissions INTEGER NOT NULL DEFAULT 1, -- Bitmask: read=1, write=2, delete=4, manage=8
    granted_by TEXT NOT NULL,
    granted_at INTEGER NOT NULL,
    
    FOREIGN KEY (entry_id) REFERENCES entries(id) ON DELETE CASCADE,
    FOREIGN KEY (user_id) REFERENCES users(id) ON DELETE CASCADE,
    FOREIGN KEY (granted_by) REFERENCES users(id),
    
    UNIQUE(entry_id, user_id)
);

CREATE INDEX idx_access_entry ON access(entry_id);
CREATE INDEX idx_access_user ON access(user_id);
CREATE INDEX idx_access_permissions ON access(permissions);
```

#### sessions
```sql
CREATE TABLE sessions (
    token TEXT PRIMARY KEY,
    user_id TEXT NOT NULL,
    expires_at INTEGER NOT NULL,
    created_at INTEGER NOT NULL,
    last_used INTEGER NOT NULL,
    user_agent TEXT,
    ip_address TEXT,
    
    FOREIGN KEY (user_id) REFERENCES users(id) ON DELETE CASCADE
);

CREATE INDEX idx_sessions_user ON sessions(user_id);
CREATE INDEX idx_sessions_expires ON sessions(expires_at);
```

#### audit_log
```sql
CREATE TABLE audit_log (
    id TEXT PRIMARY KEY,
    user_id TEXT,
    entry_id TEXT,
    action TEXT NOT NULL, -- view, create, update, delete, download, share
    details TEXT, -- JSON with action-specific data
    ip_address TEXT,
    user_agent TEXT,
    created_at INTEGER NOT NULL,
    
    FOREIGN KEY (user_id) REFERENCES users(id),
    FOREIGN KEY (entry_id) REFERENCES entries(id)
);

CREATE INDEX idx_audit_user ON audit_log(user_id);
CREATE INDEX idx_audit_entry ON audit_log(entry_id);
CREATE INDEX idx_audit_action ON audit_log(action);
CREATE INDEX idx_audit_created ON audit_log(created_at);
```

### Entry Content Schemas

#### Deal Room Entry
```json
{
  "type": "deal_room",
  "description": "Acquisition of TechCorp by PrivateEquity Partners",
  "stage": "due_diligence", // sourcing, loi, due_diligence, closing, completed
  "target_company": "TechCorp Inc.",
  "deal_value": "$50M",
  "participants": [
    {"name": "John Smith", "role": "Deal Lead", "organization": "PE Partners"},
    {"name": "Jane Doe", "role": "Analyst", "organization": "PE Partners"}
  ],
  "key_dates": {
    "loi_signed": "2024-01-15",
    "dd_start": "2024-02-01",
    "close_target": "2024-04-30"
  },
  "confidentiality_level": "highly_confidential"
}
```

#### Document Entry
```json
{
  "type": "document",
  "category": "financial_model", // nda, cim, financial_model, teaser, legal, dd_report
  "mime_type": "application/pdf",
  "original_name": "TechCorp_Financial_Model_v3.xlsx",
  "version": "3.0",
  "analysis": {
    "summary": "Financial projections showing 15% EBITDA growth",
    "key_metrics": ["Revenue: $100M", "EBITDA: $25M", "Growth: 15%"],
    "risk_factors": ["Market volatility", "Regulatory changes"],
    "ai_confidence": 0.92
  },
  "requires_nda": true
}
```

#### Note/Message Entry
```json
{
  "type": "note",
  "body": "Updated financial model reflects Q4 performance...",
  "mentions": ["user_id_123"], // @mentions for notifications
  "attachments": ["entry_id_456"], // Reference to document entries
  "thread_context": "document_discussion" // Helps organize conversations
}
```

## Permission Model (RBAC)

### Bitmask Values
- **READ (1):** View entry and metadata
- **WRITE (2):** Edit entry, add comments
- **DELETE (4):** Remove entry
- **MANAGE (8):** Grant/revoke access, manage permissions

### Permission Inheritance
- Deal room permissions cascade to all contained documents
- Explicit document permissions override inherited permissions
- Admins have MANAGE (8) on all entries by default

### Common Permission Patterns
- **Viewer:** READ (1) - Can view documents and notes
- **Contributor:** READ + WRITE (3) - Can add notes and upload documents
- **Manager:** READ + WRITE + DELETE (7) - Can manage content
- **Admin:** All permissions (15) - Full control

## API Endpoints

### Authentication
```
POST /auth/login              # Magic link login
GET  /auth/verify/{token}     # Verify magic link
POST /auth/logout             # End session
GET  /auth/me                 # Current user info
```

### Deal Rooms
```
GET    /api/deal-rooms        # List accessible deal rooms
POST   /api/deal-rooms        # Create new deal room
GET    /api/deal-rooms/{id}   # Get deal room details
PUT    /api/deal-rooms/{id}   # Update deal room
DELETE /api/deal-rooms/{id}   # Archive deal room
```

### Entries (Documents, Notes, etc.)
```
GET    /api/entries           # List entries (filtered by permissions)
POST   /api/entries           # Create entry
GET    /api/entries/{id}      # Get entry details
PUT    /api/entries/{id}      # Update entry
DELETE /api/entries/{id}      # Delete entry
GET    /api/entries/{id}/file # Download file (for documents)
```

### Access Management
```
GET    /api/entries/{id}/access     # List permissions for entry
POST   /api/entries/{id}/access     # Grant access
PUT    /api/entries/{id}/access/{uid} # Update user permissions
DELETE /api/entries/{id}/access/{uid} # Revoke access
```

### Search & AI
```
GET    /api/search?q={query}        # Semantic search across accessible content
POST   /api/analyze/{entry_id}     # Trigger AI analysis
GET    /api/similar/{entry_id}     # Find similar documents
```

### Activity & Audit
```
GET    /api/activity/{deal_room_id} # Activity feed for deal room
GET    /api/audit/{entry_id}       # Audit log for specific entry
```

## Page Routes (Server-Rendered)

```
GET  /                        # Dashboard - accessible deal rooms
GET  /login                   # Login page
GET  /deal-rooms/{id}         # Deal room detail view
GET  /deal-rooms/{id}/upload  # Document upload page
GET  /documents/{id}          # Document viewer
GET  /admin                   # Admin panel (user/permissions management)
GET  /profile                 # User profile
GET  /activity                # Global activity feed
```

## File Storage Design

### Storage Structure
```
data/
├── db/
│   └── dealroom.db           # SQLite database
├── files/
│   ├── 2024/01/              # Date-based partitioning
│   │   ├── abc123.enc        # Encrypted + compressed files
│   │   └── def456.enc
│   └── temp/                 # Temporary upload staging
└── backups/                  # Automated backups
    ├── db/
    └── files/
```

### Encryption Process
1. **Upload:** File uploaded to `/temp/{uuid}`
2. **Compress:** Apply zstd compression (level 3)
3. **Encrypt:** AES-256-GCM with random nonce
4. **Store:** Move to date-partitioned directory
5. **Index:** Store metadata + embedding in database
6. **Cleanup:** Remove temp file

### File Naming
- **Pattern:** `{year}/{month}/{entry_id}.enc`
- **Metadata:** Stored in database, not filesystem
- **Deduplication:** SHA-256 hash prevents duplicate storage

## AI/Embeddings Pipeline

### Document Processing Workflow
1. **Upload:** User uploads document
2. **Extract:** Convert to text (PDF, DOCX, XLSX support)
3. **Analyze:** Send to K2.5 for:
   - Content summarization
   - Key metrics extraction
   - Risk factor identification
   - Classification (NDA, CIM, Financial Model, etc.)
4. **Embed:** Generate vector embeddings for semantic search
5. **Store:** Save analysis results in entry content JSON

### K2.5 Integration
```go
type DocumentAnalysis struct {
    Summary      string   `json:"summary"`
    KeyMetrics   []string `json:"key_metrics"`
    RiskFactors  []string `json:"risk_factors"`
    Category     string   `json:"category"`
    Confidence   float64  `json:"ai_confidence"`
}

type EmbeddingRequest struct {
    Text     string `json:"text"`
    Model    string `json:"model"`
}
```

### Semantic Search
- **Vector Storage:** SQLite with vector extension
- **Similarity:** Cosine similarity for document matching
- **Hybrid Search:** Combine keyword + semantic results
- **Access Control:** Filter results by user permissions

## Security Model

### Authentication
- **Magic Link:** Email-based passwordless login
- **Session Management:** Secure HTTP-only cookies
- **Token Expiry:** 24-hour sessions with automatic refresh
- **Rate Limiting:** Prevent brute force attacks

### Authorization
- **RBAC:** Entry-level permissions with inheritance
- **Least Privilege:** Users see only what they have access to
- **Audit Trail:** All actions logged with user attribution
- **Admin Controls:** User management and permission oversight

### Data Protection
- **Encryption at Rest:** AES-256-GCM for files, encrypted SQLite
- **Encryption in Transit:** HTTPS only, HSTS headers
- **File Access:** Direct file serving prevented, all through API
- **Backup Encryption:** Automated encrypted backups

### Compliance Features
- **Audit Logging:** Comprehensive activity tracking
- **Data Retention:** Configurable retention policies
- **Access Reviews:** Periodic permission audits
- **Export Controls:** Document download tracking

## Deployment Architecture

### Single Binary Approach
```
dealroom
├── Static assets embedded (CSS, JS)
├── Templates compiled
├── Database migrations
└── Configuration via environment variables
```

### Configuration
```bash
# Database
DB_PATH=/data/db/dealroom.db
DB_KEY=<encryption_key>

# File Storage
FILES_PATH=/data/files
BACKUP_PATH=/data/backups

# AI Service
K25_API_URL=http://k2.5:8080
K25_API_KEY=<api_key>

# Server
PORT=8080
BASE_URL=https://dealroom.company.com
SESSION_SECRET=<random_key>

# Email (for magic links)
SMTP_HOST=smtp.company.com
SMTP_USER=dealroom@company.com
SMTP_PASS=<password>
```

### Docker Deployment
```dockerfile
FROM golang:1.22-alpine AS builder
# ... build process

FROM alpine:3.19
RUN apk --no-cache add ca-certificates tzdata
COPY --from=builder /app/dealroom /usr/local/bin/
VOLUME ["/data"]
EXPOSE 8080
CMD ["dealroom"]
```

## Development Workflow

### Project Structure
```
dealroom/
├── cmd/dealroom/main.go      # Application entry point
├── internal/
│   ├── db/                   # Database layer
│   ├── rbac/                 # RBAC engine
│   ├── store/               # File storage
│   ├── ai/                  # K2.5 integration
│   ├── handler/             # HTTP handlers
│   └── model/               # Data models
├── templates/               # templ templates
├── static/                  # Static assets
├── migrations/              # Database migrations
├── Dockerfile
├── Makefile
└── README.md
```

### Build & Run
```bash
make build      # Build binary
make run        # Run in development mode
make test       # Run tests
make migrate    # Run database migrations
make docker     # Build Docker image
```

### Testing Strategy
- **Unit Tests:** Core business logic and RBAC
- **Integration Tests:** Database and file operations
- **E2E Tests:** Critical user journeys with real browser
- **Security Tests:** Permission boundaries and file access
- **Performance Tests:** Large file uploads and search

## Scalability Considerations

### Current Limits (SQLite-based)
- **Concurrent Users:** ~100-200 active users
- **File Storage:** Limited by disk space
- **Search Performance:** Good up to ~10K documents
- **Database Size:** Efficient up to ~100GB

### Migration Path (Future)
- **Database:** PostgreSQL for higher concurrency
- **File Storage:** S3-compatible object storage
- **Search:** Dedicated vector database (Pinecone, Weaviate)
- **Caching:** Redis for session and query caching

## Success Metrics

### Technical Metrics
- **Uptime:** >99.9% availability
- **Response Time:** <200ms for page loads
- **File Upload:** <30s for 100MB files
- **Search Latency:** <500ms for semantic search

### Business Metrics
- **User Adoption:** Active users per deal room
- **Document Velocity:** Files uploaded/downloaded per day
- **Security Events:** Zero unauthorized access incidents
- **User Satisfaction:** NPS > 8 for ease of use

## Risk Assessment

### Technical Risks
- **Single Point of Failure:** SQLite limits high availability
- **File Corruption:** Encryption key loss = data loss
- **AI Dependency:** K2.5 service availability required
- **Scaling Challenges:** May need architecture changes at scale

### Mitigation Strategies
- **Automated Backups:** Hourly encrypted backups to S3
- **Key Management:** Secure key storage and rotation
- **Circuit Breakers:** Graceful degradation when AI unavailable
- **Monitoring:** Comprehensive health checks and alerting

### Security Risks
- **Data Breach:** Highly sensitive financial information
- **Insider Threat:** Authorized users with malicious intent
- **Compliance:** Regulatory requirements for financial data
- **Access Control:** Complex permission inheritance bugs

### Security Controls
- **Defense in Depth:** Multiple security layers
- **Principle of Least Privilege:** Minimal required permissions
- **Comprehensive Auditing:** All actions logged and monitored
- **Regular Reviews:** Periodic security assessments

## Implementation Phases

### Phase 1: Core Platform (4 weeks)
- Basic authentication and session management
- Deal room creation and management
- Document upload with encryption
- Basic RBAC implementation

### Phase 2: Collaboration Features (3 weeks)
- Notes and messaging system
- Activity feeds and notifications
- Advanced permission management
- Search functionality

### Phase 3: AI Integration (2 weeks)
- K2.5 document analysis
- Embeddings and semantic search
- Document summarization
- Similar document recommendations

### Phase 4: Production Readiness (2 weeks)
- Comprehensive audit logging
- Admin dashboard
- Performance optimization
- Security hardening

### Phase 5: Advanced Features (3 weeks)
- Deal stage tracking
- Bulk operations
- API for integrations
- Advanced reporting

Total estimated development time: **14 weeks** with dedicated development team.

## Conclusion

Deal Room represents a modern, security-first approach to Investment Banking document management. By leveraging the proven inou-portal pattern with Go's performance characteristics and AI-enhanced document analysis, we deliver a solution that meets the demanding requirements of financial services while maintaining operational simplicity through single-binary deployment.

The architecture prioritizes security, auditability, and user experience while providing a clear path for future scalability as the platform grows.