/**
 * Test setup for @suaveplan/health-check.
 *
 * Installs a real in-memory OpenTelemetry MeterProvider BEFORE any source
 * module imports so the meter resolved on first call binds to it.
 */
import { webcrypto } from "node:crypto";
import { metrics } from "@opentelemetry/api";
import {
    AggregationTemporality,
    InMemoryMetricExporter,
    MeterProvider,
    PeriodicExportingMetricReader,
} from "@opentelemetry/sdk-metrics";

type WritableGlobal = { crypto?: Crypto };
const g = globalThis as WritableGlobal;
if (g.crypto === undefined) {
    g.crypto = webcrypto as unknown as Crypto;
}

export const testInMemoryMetricExporter = new InMemoryMetricExporter(
    AggregationTemporality.CUMULATIVE
);

const reader = new PeriodicExportingMetricReader({
    exporter: testInMemoryMetricExporter,
    exportIntervalMillis: 60_000,
});

export const testMeterProvider = new MeterProvider({ readers: [reader] });
metrics.setGlobalMeterProvider(testMeterProvider);

export async function flushTestMetrics() {
    await testMeterProvider.forceFlush();
    const collected = testInMemoryMetricExporter.getMetrics();
    testInMemoryMetricExporter.reset();
    return collected;
}