/*##############################################################################

    HPCC SYSTEMS software Copyright (C) 2021 HPCC Systems®.

    Licensed under the Apache License, Version 2.0 (the "License");
    you may not use this file except in compliance with the License.
    You may obtain a copy of the License at

       http://www.apache.org/licenses/LICENSE-2.0

    Unless required by applicable law or agreed to in writing, software
    distributed under the License is distributed on an "AS IS" BASIS,
    WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
    See the License for the specific language governing permissions and
    limitations under the License.
############################################################################## */

#ifdef _USE_CPPUNIT

#include <cppunit/TestFixture.h>
#include "unittests.hpp"
#include <algorithm>

#include "jptree.hpp"
#include "jmetrics.hpp"

using namespace hpccMetrics;

class PeriodicTestSink : public PeriodicMetricSink
{
public:
    explicit PeriodicTestSink(const char *name, const IPropertyTree *pSettingsTree) :
        PeriodicMetricSink(name, "test", pSettingsTree) { }

    ~PeriodicTestSink() = default;

protected:
    virtual void prepareToStartCollecting() override
    {
        prepareCalled = true;
        numCollections = 0;
    }

    virtual void collectingHasStopped() override
    {
        stopCollectionNotificationCalled = true;
    }

    void doCollection() override
    {
        numCollections++;
    }

public:
    bool prepareCalled = false;
    bool stopCollectionNotificationCalled = false;
    unsigned numCollections = 0;
};


const char *periodicSinkSettingsTestYml = R"!!(period: 2
)!!";

static const unsigned period = 2;


class PeriodicSinkTests : public CppUnit::TestFixture
{
public:
    PeriodicSinkTests()
    {
        //
        // Load the settings then set the period using the global var
        Owned<IPropertyTree> pSettings = createPTreeFromYAMLString(periodicSinkSettingsTestYml, ipt_none, ptr_ignoreWhiteSpace, nullptr);
        pSettings->setPropInt("@period", period);
        pPeriodicTestSink = new PeriodicTestSink("periodic_test_sink", pSettings);
        periodicSinkTestReporter.addSink(pPeriodicTestSink, "periodic_test_sink");
    }

    ~PeriodicSinkTests() = default;

    CPPUNIT_TEST_SUITE(PeriodicSinkTests);
        CPPUNIT_TEST(Test_sets_period_correctly);
    CPPUNIT_TEST_SUITE_END();

protected:

    void Test_sets_period_correctly()
    {
        //
        // To test setting the period correctly, start collection and delay a multiple of that period.
        // Stop collection and ask the test sink how many collections were done. If the count is +/- 1
        // from the wait period multiple used, then we are close enough
        unsigned multiple = 3;
        periodicSinkTestReporter.startCollecting();

        //
        // Check that the sink called to prepare for collection
        CPPUNIT_ASSERT(pPeriodicTestSink->prepareCalled);

        // wait... then stop collecting
        sleep(multiple * period);
        periodicSinkTestReporter.stopCollecting();

        unsigned numCollections = pPeriodicTestSink->numCollections;

        bool numReportsCorrect = (numCollections >= multiple-1) && (numCollections <= multiple+1);
        CPPUNIT_ASSERT_EQUAL(true, numReportsCorrect);

        //
        // Verify collection was stopped
        CPPUNIT_ASSERT(pPeriodicTestSink->stopCollectionNotificationCalled);
    }

protected:
    MetricsReporter periodicSinkTestReporter;
    PeriodicTestSink *pPeriodicTestSink = nullptr;
};

CPPUNIT_TEST_SUITE_REGISTRATION( PeriodicSinkTests );
CPPUNIT_TEST_SUITE_NAMED_REGISTRATION( PeriodicSinkTests, "PeriodicSinkTests" );

#endif