// Copyright 2014 The Flutter Authors. All rights reserved.
// Use of this source code is governed by a BSD-style license that can be
// found in the LICENSE file.

import 'dart:ui';

import 'package:flutter_test/flutter_test.dart';

void main() {
  group(FrameTimingSummarizer, () {
    test('calculates all fields', () {
      List<int> vsyncTimes = <int>[
        for (int i = 0; i < 100; i += 1) 100 * (i + 1),
      ];
      List<int> buildTimes = <int>[
        for (int i = 0; i < 100; i += 1) vsyncTimes[i] + 1000 * (i + 1),
      ];
      List<int> rasterTimes = <int>[
        for (int i = 0; i < 100; i += 1) 1000 * (i + 1) + 1000,
      ];
      // reversed to make sure sort is working.
      buildTimes = buildTimes.reversed.toList();
      rasterTimes = rasterTimes.reversed.toList();
      vsyncTimes = vsyncTimes.reversed.toList();
      final List<FrameTiming> inputData = <FrameTiming>[
        for (int i = 0; i < 100; i += 1)
          FrameTiming(
            vsyncStart: 0,
            buildStart: vsyncTimes[i],
            buildFinish: buildTimes[i],
            rasterStart: 500,
            rasterFinish: rasterTimes[i],
            // Wall time should not be used in any profiling metrics.
            // It is primarily to correlate with external tools' measurement.
            rasterFinishWallTime: 0,
          ),
      ];

      final FrameTimingSummarizer summary = FrameTimingSummarizer(inputData);
      expect(summary.averageFrameBuildTime.inMicroseconds, 50500);
      expect(summary.p90FrameBuildTime.inMicroseconds, 90000);
      expect(summary.p99FrameBuildTime.inMicroseconds, 99000);
      expect(summary.worstFrameBuildTime.inMicroseconds, 100000);
      expect(summary.missedFrameBuildBudget, 84);

      expect(summary.averageFrameRasterizerTime.inMicroseconds, 51000);
      expect(summary.p90FrameRasterizerTime.inMicroseconds, 90500);
      expect(summary.p99FrameRasterizerTime.inMicroseconds, 99500);
      expect(summary.worstFrameRasterizerTime.inMicroseconds, 100500);
      expect(summary.missedFrameRasterizerBudget, 85);
      expect(summary.frameBuildTime.length, 100);

      expect(summary.averageVsyncOverhead.inMicroseconds, 5050);
      expect(summary.p90VsyncOverhead.inMicroseconds, 9000);
      expect(summary.p99VsyncOverhead.inMicroseconds, 9900);
      expect(summary.worstVsyncOverhead.inMicroseconds, 10000);
    });

    group('missed budget count', () {
      test('when single element missed budget', () {
        final FrameTimingSummarizer summary = FrameTimingSummarizer(<FrameTiming>[
          FrameTiming(
            buildStart: 0,
            buildFinish: (kBuildBudget + const Duration(microseconds: 1)).inMicroseconds,
            vsyncStart: 0,
            rasterStart: 0,
            rasterFinish: 0,
            rasterFinishWallTime: 0,
          ),
        ]);
        expect(summary.missedFrameBuildBudget, 1);
      });

      test('when single element within budget', () {
        final FrameTimingSummarizer summary = FrameTimingSummarizer(<FrameTiming>[
          FrameTiming(
            buildStart: 0,
            buildFinish: 0,
            vsyncStart: 0,
            rasterStart: 0,
            rasterFinish: 0,
            rasterFinishWallTime: 0,
          ),
        ]);
        expect(summary.missedFrameBuildBudget, 0);
      });

      test('when single element exactly within budget', () {
        final FrameTimingSummarizer summary = FrameTimingSummarizer(<FrameTiming>[
          FrameTiming(
            buildStart: 0,
            buildFinish: kBuildBudget.inMicroseconds,
            vsyncStart: 0,
            rasterStart: 0,
            rasterFinish: 0,
            rasterFinishWallTime: 0,
          ),
        ]);
        expect(summary.missedFrameBuildBudget, 0);
      });

      test('when many missed budget', () {
        final FrameTimingSummarizer summary = FrameTimingSummarizer(<FrameTiming>[
          FrameTiming(
            buildStart: 0,
            buildFinish: 0,
            vsyncStart: 0,
            rasterStart: 0,
            rasterFinish: 0,
            rasterFinishWallTime: 0,
          ),
          FrameTiming(
            buildStart: 0,
            buildFinish: kBuildBudget.inMicroseconds,
            vsyncStart: 0,
            rasterStart: 0,
            rasterFinish: 0,
            rasterFinishWallTime: 0,
          ),
          FrameTiming(
            buildStart: 0,
            buildFinish: (kBuildBudget + const Duration(microseconds: 1)).inMicroseconds,
            vsyncStart: 0,
            rasterStart: 0,
            rasterFinish: 0,
            rasterFinishWallTime: 0,
          ),
          FrameTiming(
            buildStart: 0,
            buildFinish: (kBuildBudget + const Duration(microseconds: 2)).inMicroseconds,
            vsyncStart: 0,
            rasterStart: 0,
            rasterFinish: 0,
            rasterFinishWallTime: 0,
          ),
        ]);
        expect(summary.missedFrameBuildBudget, 2);
      });
    });
  });
}