// Copyright 2022 The Chromium Authors
// Use of this source code is governed by a BSD-style license that can be
// found in the LICENSE file.

#include "content/browser/preloading/prerender/prerender_metrics.h"

#include "base/test/metrics/histogram_tester.h"
#include "content/public/browser/preloading_trigger_type.h"
#include "net/http/http_request_headers.h"
#include "testing/gtest/include/gtest/gtest.h"

namespace content {
namespace {

// Tests to ensure the ReportHeaderMismatch implementation is aligned with the
// enum generator.
TEST(PrerenderMetricsTest, NavigationHeaderMismatchMetric) {
  const char kMetricName[] =
      "Prerender.Experimental.ActivationHeadersMismatch.ForTesting";
  {
    base::HistogramTester histogram_tester;
    PrerenderCancellationReason reason = PrerenderCancellationReason::
        CreateCandidateReasonForActivationParameterMismatch();
    net::HttpRequestHeaders prerender_headers;
    prerender_headers.SetHeader("Content-Type", "ab");
    prerender_headers.SetHeader("If-Match", "xy");
    net::HttpRequestHeaders potential_headers;
    potential_headers.SetHeader("Content-Type", "cd");
    potential_headers.SetHeader("If-Match", "xy");
    ASSERT_FALSE(PrerenderHost::IsActivationHeaderMatch(
        potential_headers, prerender_headers, reason));
    reason.ReportMetrics(".ForTesting");
    // label="content-type: value mismatch"
    histogram_tester.ExpectUniqueSample(kMetricName, 808179719, 1);
  }
  {
    base::HistogramTester histogram_tester;
    PrerenderCancellationReason reason = PrerenderCancellationReason::
        CreateCandidateReasonForActivationParameterMismatch();
    net::HttpRequestHeaders prerender_headers;
    prerender_headers.SetHeader("Content-Type", "ab");
    net::HttpRequestHeaders potential_headers;
    potential_headers.SetHeader("Content-Type", "ab");
    potential_headers.SetHeader("If-Match", "xys");
    ASSERT_FALSE(PrerenderHost::IsActivationHeaderMatch(
        potential_headers, prerender_headers, reason));
    reason.ReportMetrics(".ForTesting");
    // label="if-match: missing in prerendering request's headers"
    histogram_tester.ExpectUniqueSample(kMetricName, 667272509, 1);
  }
  {
    base::HistogramTester histogram_tester;
    PrerenderCancellationReason reason = PrerenderCancellationReason::
        CreateCandidateReasonForActivationParameterMismatch();
    net::HttpRequestHeaders prerender_headers;
    prerender_headers.SetHeader("service-worker", "xyz");
    net::HttpRequestHeaders potential_headers;
    ASSERT_FALSE(PrerenderHost::IsActivationHeaderMatch(
        potential_headers, prerender_headers, reason));
    reason.ReportMetrics(".ForTesting");
    // label="service-worker: missing in activation request's headers"
    histogram_tester.ExpectUniqueSample(kMetricName, -578377770, 1);
  }
}

}  // namespace
}  // namespace content