/*
using Svrnty.CQRS.Events.Subscriptions;
using Svrnty.CQRS.Events.Abstractions.Models;
 * EXAMPLE: OpenTelemetry Integration with Prometheus Exporter
 *
 * This file demonstrates how to integrate Svrnty.CQRS.Events metrics
 * with OpenTelemetry and expose them via Prometheus endpoint.
 *
 * INSTALLATION:
 *
 * dotnet add package OpenTelemetry.Extensions.Hosting
 * dotnet add package OpenTelemetry.Instrumentation.AspNetCore
 * dotnet add package OpenTelemetry.Exporter.Prometheus.AspNetCore --prerelease
 *
 * USAGE in Program.cs:
 */

#if FALSE // This is example code, not compiled

using OpenTelemetry.Metrics;

var builder = WebApplication.CreateBuilder(args);

// Register event streaming with metrics
builder.Services.AddSvrntyEvents();
builder.Services.AddEventStreamMetrics(); // Phase 6: Add metrics collection

// Configure OpenTelemetry with Prometheus exporter
builder.Services.AddOpenTelemetry()
    .WithMetrics(metrics => metrics
        // Add ASP.NET Core instrumentation
        .AddAspNetCoreInstrumentation()

        // Add Svrnty.CQRS.Events metrics
        .AddMeter("Svrnty.CQRS.Events")

        // Export to Prometheus (scraping endpoint)
        .AddPrometheusExporter());

var app = builder.Build();

// Map Prometheus scraping endpoint at /metrics
app.MapPrometheusScrapingEndpoint();

// ... rest of your configuration

app.Run();

/*
 * PROMETHEUS CONFIGURATION (prometheus.yml):
 *
 * scrape_configs:
 *   - job_name: 'svrnty-cqrs-events'
 *     scrape_interval: 5s
 *     static_configs:
 *       - targets: ['localhost:6001']
 *
 * AVAILABLE METRICS:
 *
 * Counters (cumulative):
 *   - svrnty_cqrs_events_published_total{stream="UserWorkflow",event_type="UserAddedEvent"}
 *   - svrnty_cqrs_events_consumed_total{stream="UserWorkflow",subscription="user-analytics",event_type="UserAddedEvent"}
 *   - svrnty_cqrs_events_errors_total{stream="UserWorkflow",subscription="...",error_type="ValidationError"}
 *   - svrnty_cqrs_events_retries_total{stream="UserWorkflow",subscription="...",attempt="1"}
 *
 * Histograms (distributions):
 *   - svrnty_cqrs_events_processing_latency_milliseconds{stream="UserWorkflow",subscription="..."}
 *     - _bucket{le="10"}
 *     - _bucket{le="50"}
 *     - _bucket{le="100"}
 *     - _bucket{le="500"}
 *     - _bucket{le="1000"}
 *     - _bucket{le="+Inf"}
 *     - _sum
 *     - _count
 *
 * Gauges (current values):
 *   - svrnty_cqrs_events_consumer_lag{stream="UserWorkflow",subscription="user-analytics"}
 *   - svrnty_cqrs_events_stream_length{stream="UserWorkflow"}
 *   - svrnty_cqrs_events_active_consumers{stream="UserWorkflow",subscription="user-analytics"}
 *
 * GRAFANA DASHBOARD EXAMPLE QUERIES:
 *
 * Event Publish Rate (events/sec):
 *   rate(svrnty_cqrs_events_published_total[5m])
 *
 * Event Consumption Rate by Subscription:
 *   rate(svrnty_cqrs_events_consumed_total{subscription="user-analytics"}[5m])
 *
 * Consumer Lag (current):
 *   svrnty_cqrs_events_consumer_lag
 *
 * P95 Processing Latency:
 *   histogram_quantile(0.95,
 *     rate(svrnty_cqrs_events_processing_latency_milliseconds_bucket[5m]))
 *
 * Error Rate:
 *   rate(svrnty_cqrs_events_errors_total[5m])
 *
 * Active Consumers:
 *   svrnty_cqrs_events_active_consumers
 */

#endif