# Analytics Service

Real-time analytics and reporting service for the Telegram Marketing Intelligence Agent system.

## Overview

The Analytics service provides comprehensive event tracking, metrics processing, real-time analytics, report generation, and alert management capabilities.

## Features

### Event Tracking
- Real-time event ingestion
- Batch event processing
- Event validation and enrichment
- Multi-dimensional event storage

### Metrics Processing
- Custom metric definitions
- Real-time metric calculation
- Aggregation and rollups
- Time-series data management

### Report Generation
- Scheduled report generation
- Custom report templates
- Multiple export formats (PDF, Excel, CSV)
- Report distribution

### Real-time Analytics
- WebSocket streaming
- Live dashboards
- Real-time alerts
- Performance monitoring

### Alert Management
- Threshold-based alerts
- Anomaly detection
- Multi-channel notifications
- Alert history tracking

## Architecture

```
┌─────────────────┐     ┌──────────────────┐     ┌─────────────────┐
│   API Gateway   │────▶│ Analytics Service │────▶│   Elasticsearch │
└─────────────────┘     └──────────────────┘     └─────────────────┘
                               │                           │
                               ├───────────────────────────┤
                               ▼                           ▼
                        ┌─────────────┐           ┌──────────────┐
                        │   MongoDB   │           │  ClickHouse  │
                        └─────────────┘           └──────────────┘
```

## API Endpoints

### Events
- `POST /api/events` - Track single event
- `POST /api/events/batch` - Track multiple events
- `GET /api/events/search` - Search events

### Metrics
- `GET /api/metrics` - List all metrics
- `POST /api/metrics` - Create custom metric
- `GET /api/metrics/:id` - Get metric details
- `GET /api/metrics/:id/data` - Get metric data

### Reports
- `GET /api/reports` - List reports
- `POST /api/reports` - Generate report
- `GET /api/reports/:id` - Get report details
- `GET /api/reports/:id/download` - Download report

### Alerts
- `GET /api/alerts` - List alerts
- `POST /api/alerts` - Create alert
- `PUT /api/alerts/:id` - Update alert
- `DELETE /api/alerts/:id` - Delete alert
- `GET /api/alerts/:id/history` - Get alert history

### Real-time
- `WS /ws/analytics` - Real-time analytics stream
- `WS /ws/metrics/:id` - Metric-specific stream

## Data Models

### Event Schema
```javascript
{
  eventId: String,
  accountId: String,
  sessionId: String,
  eventType: String,
  eventName: String,
  timestamp: Date,
  properties: Object,
  context: {
    ip: String,
    userAgent: String,
    locale: String
  }
}
```

### Metric Schema
```javascript
{
  metricId: String,
  accountId: String,
  name: String,
  type: String, // 'counter', 'gauge', 'histogram'
  unit: String,
  formula: String,
  aggregation: String,
  filters: Array,
  dimensions: Array
}
```

### Report Schema
```javascript
{
  reportId: String,
  accountId: String,
  name: String,
  template: String,
  schedule: String,
  parameters: Object,
  recipients: Array,
  format: String
}
```

### Alert Schema
```javascript
{
  alertId: String,
  accountId: String,
  name: String,
  metric: String,
  condition: Object,
  threshold: Number,
  severity: String,
  channels: Array,
  cooldown: Number
}
```

## Configuration

### Environment Variables
- `PORT` - Service port (default: 3004)
- `MONGODB_URI` - MongoDB connection string
- `ELASTICSEARCH_NODE` - Elasticsearch URL
- `CLICKHOUSE_HOST` - ClickHouse host
- `REDIS_URL` - Redis connection URL
- `RABBITMQ_URL` - RabbitMQ connection URL

### Storage Configuration
- `REPORTS_DIR` - Report storage directory
- `EXPORTS_DIR` - Export storage directory
- `RETENTION_DAYS` - Data retention period

### Processing Configuration
- `BATCH_SIZE` - Event batch size
- `PROCESSING_INTERVAL` - Processing interval (ms)
- `STREAM_BUFFER_SIZE` - Real-time buffer size

## Deployment

### Docker
```bash
docker build -t analytics-service .
docker run -p 3004:3004 --env-file .env analytics-service
```

### Kubernetes
```bash
kubectl apply -f k8s/deployment.yaml
kubectl apply -f k8s/service.yaml
```

## Usage Examples

### Track Event
```javascript
const event = {
  eventType: 'message',
  eventName: 'message_sent',
  properties: {
    campaignId: '123',
    groupId: '456',
    messageType: 'text',
    charactersCount: 150
  }
};

await analyticsClient.trackEvent(event);
```

### Create Custom Metric
```javascript
const metric = {
  name: 'Message Delivery Rate',
  type: 'gauge',
  formula: '(delivered / sent) * 100',
  unit: 'percentage',
  aggregation: 'avg',
  dimensions: ['campaignId', 'groupId']
};

await analyticsClient.createMetric(metric);
```

### Generate Report
```javascript
const report = {
  template: 'campaign_performance',
  parameters: {
    campaignId: '123',
    dateRange: {
      start: '2024-01-01',
      end: '2024-01-31'
    }
  },
  format: 'pdf'
};

const result = await analyticsClient.generateReport(report);
```

### Create Alert
```javascript
const alert = {
  name: 'High Error Rate',
  metric: 'error_rate',
  condition: 'greater_than',
  threshold: 5,
  severity: 'critical',
  channels: ['email', 'slack']
};

await analyticsClient.createAlert(alert);
```

## Monitoring

### Health Check
```bash
curl http://localhost:3004/health
```

### Metrics
- Prometheus metrics available at `/metrics`
- Grafana dashboards included in `/dashboards`

### Logging
- Structured JSON logging
- Log levels: error, warn, info, debug
- Logs shipped to Elasticsearch

## Development

### Setup
```bash
npm install
cp .env.example .env
npm run dev
```

### Testing
```bash
npm test
npm run test:integration
npm run test:e2e
```

### Code Quality
```bash
npm run lint
npm run format
npm run type-check
```

## Best Practices

1. **Event Tracking**
   - Use consistent event naming
   - Include relevant context
   - Batch events when possible
   - Validate event schema

2. **Metrics Design**
   - Keep metrics simple and focused
   - Use appropriate aggregations
   - Consider cardinality
   - Plan for scale

3. **Report Generation**
   - Schedule during off-peak hours
   - Use caching for common reports
   - Optimize queries
   - Monitor generation time

4. **Alert Configuration**
   - Set appropriate thresholds
   - Use severity levels wisely
   - Configure cooldown periods
   - Test alert channels

## Security

- JWT authentication for API access
- Field-level encryption for sensitive data
- Rate limiting per account
- Audit logging for all operations
- RBAC for multi-tenant access

## Performance

- Event ingestion: 10K events/second
- Query response: <100ms p99
- Report generation: <30s for standard reports
- Real-time latency: <50ms

## Support

For issues and questions:
- Check the documentation
- Review common issues in FAQ
- Contact the development team