# Portfolio Manager

## Overview
The Portfolio Manager service will provide comprehensive position tracking, portfolio analysis, and management capabilities for the stock-bot platform. It will maintain the current state of all trading portfolios, calculate performance metrics, and support portfolio-level decision making.

## Planned Features

### Position Management
- **Real-time Position Tracking**: Accurate tracking of all open positions
- **Position Reconciliation**: Validation against broker records
- **Average Price Calculation**: Tracking of position entry prices
- **Lot Management**: FIFO/LIFO/average cost basis tracking
- **Multi-currency Support**: Handling positions across different currencies

### Portfolio Analytics
- **Performance Metrics**: Return calculation (absolute, relative, time-weighted)
- **Risk Metrics**: Volatility, beta, correlation, VaR calculations
- **Attribution Analysis**: Performance attribution by sector, strategy, asset class
- **Scenario Analysis**: What-if analysis for portfolio changes
- **Benchmark Comparison**: Performance vs. standard benchmarks

### Corporate Action Processing
- **Dividend Processing**: Impact of cash and stock dividends
- **Split Adjustments**: Handling of stock splits and reverse splits
- **Merger & Acquisition Handling**: Position adjustments for M&A events
- **Rights & Warrants**: Processing of corporate rights events
- **Spin-offs**: Management of position changes from spin-off events

### Portfolio Construction
- **Rebalancing Tools**: Portfolio rebalancing against targets
- **Optimization**: Portfolio optimization for various objectives
- **Constraint Management**: Enforcement of portfolio constraints
- **Tax-aware Trading**: Consideration of tax implications
- **Cash Management**: Handling of cash positions and forecasting

## Planned Integration Points

### Upstream Connections
- Order Management System (for executed trades)
- Broker Gateway (for position verification)
- Market Data Gateway (for pricing)
- Strategy Orchestrator (for allocation decisions)

### Downstream Consumers
- Risk Guardian (for portfolio risk assessment)
- Trading Dashboard (for portfolio visualization)
- Reporting System (for performance reporting)
- Tax Reporting (for tax calculations)

## Planned Technical Implementation

### Technology Stack
- **Runtime**: Node.js with TypeScript
- **Database**: Fast database with transaction support
- **Calculation Engine**: Optimized financial calculation libraries
- **API**: RESTful interface with WebSocket updates
- **Caching**: In-memory position cache for performance

### Architecture Pattern
- Event sourcing for position history
- CQRS for optimized read/write operations
- Eventual consistency for distributed state
- Snapshotting for performance optimization

## Development Guidelines

### Position Calculations
- Cost basis methodologies
- Corporate action handling
- FX conversion approaches
- Performance calculation standards

### Data Consistency
- Reconciliation procedures
- Error detection and correction
- Data validation requirements
- Audit trail requirements

### Performance Optimization
- Caching strategies
- Calculation optimization
- Query patterns
- Batch processing approaches

## Implementation Roadmap
1. Basic position tracking and P&L calculation
2. Portfolio analytics and performance metrics
3. Corporate action processing
4. Advanced portfolio construction tools
5. Tax and regulatory reporting features