package server

import (
	"net/http"
	"net/http/httptest"
	"strings"
	"testing"

	"github.com/prometheus/client_golang/prometheus/promhttp"
)

// TestMetricsRecordRequestsOnlyWithMetricsUsername checks that the router
// records nothing about the requests it serves while no metrics username is
// set, and that with one set /metrics reports a request it served. The two
// halves are one test, run in this order, because the router records into
// the process-wide Prometheus registry, which only one test in this package
// can set up and which keeps what is recorded in it.
func TestMetricsRecordRequestsOnlyWithMetricsUsername(t *testing.T) {
	t.Parallel()

	// The line /metrics shows once the router has served one GET /robots.txt.
	const robotsRequestCount = `http_request_duration_seconds_count{` +
		`code="200",handler="/robots.txt",method="GET",service=""} 1`

	s := newTestServer(t)
	s.ServeHTTP(httptest.NewRecorder(), httptest.NewRequestWithContext(
		t.Context(), http.MethodGet, "/robots.txt", nil))

	// With no metrics username the router serves no /metrics, so the
	// registry is read directly.
	registry := httptest.NewRecorder()
	promhttp.Handler().ServeHTTP(registry, httptest.NewRequestWithContext(
		t.Context(), http.MethodGet, "/metrics", nil))

	if strings.Contains(registry.Body.String(), "http_request_duration_seconds") {
		t.Errorf("with no metrics username a request was recorded:\n%s",
			registry.Body.String())
	}

	s.config.MetricsUsername = "metricsuser"
	s.config.MetricsPassword = "metricspass"
	s.SetupRoutes()

	s.ServeHTTP(httptest.NewRecorder(), httptest.NewRequestWithContext(
		t.Context(), http.MethodGet, "/robots.txt", nil))

	req := httptest.NewRequestWithContext(
		t.Context(), http.MethodGet, "/metrics", nil)
	req.SetBasicAuth("metricsuser", "metricspass")

	rec := httptest.NewRecorder()
	s.ServeHTTP(rec, req)

	if rec.Code != http.StatusOK {
		t.Fatalf("GET /metrics status = %d, want %d", rec.Code, http.StatusOK)
	}

	if !strings.Contains(rec.Body.String(), robotsRequestCount) {
		t.Errorf("/metrics does not report the GET /robots.txt served; "+
			"want the line %q in:\n%s", robotsRequestCount, rec.Body.String())
	}
}