// Copyright (c) Microsoft Corporation. All rights reserved.
// Licensed under the MIT License.

#include "pch.h"
#include <WexTestClass.h>

#include "CalcViewModel\DataLoaders\CurrencyDataLoader.h"
#include "CalcViewModel\Common\LocalizationService.h"

using namespace CalculatorApp::Common;
using namespace CalculatorApp::Common::LocalizationServiceProperties;
using namespace CalculatorApp::DataLoaders;
using namespace CalculatorApp::ViewModel;
using namespace CalculatorUnitTests;
using namespace Concurrency;
using namespace Platform;
using namespace std;
using namespace UnitConversionManager;
using namespace Windows::Foundation;
using namespace Windows::Storage;
using namespace Windows::Web::Http;

namespace CalculatorApp
{
    namespace DataLoaders
    {
        class MockCurrencyHttpClientWithResult : public CurrencyHttpClient
        {
        public:
            MockCurrencyHttpClientWithResult(String^ staticResponse, String^ allRatiosResponse) :
                m_staticResponse(staticResponse),
                m_allRatiosResponse(allRatiosResponse)
            {
            }

            IAsyncOperationWithProgress<String^, HttpProgress>^ GetCurrencyMetadata() override
            {
                return ref new MockAsyncOperationWithProgress(m_staticResponse);
            }

            IAsyncOperationWithProgress<String^, HttpProgress>^ GetCurrencyRatios() override
            {
                return ref new MockAsyncOperationWithProgress(m_allRatiosResponse);
            }

        private:
            String^ m_staticResponse;
            String^ m_allRatiosResponse;
        };

        class MockCurrencyHttpClientThrowsException : public CurrencyHttpClient
        {
        public:
            MockCurrencyHttpClientThrowsException() {}

            IAsyncOperationWithProgress<String^, HttpProgress>^ GetCurrencyMetadata() override
            {
                throw ref new NotImplementedException();
            }

            IAsyncOperationWithProgress<String^, HttpProgress>^ GetCurrencyRatios() override
            {
                throw ref new NotImplementedException();
            }
        };
    }
}

class DataLoadedCallback : public UnitConversionManager::IViewModelCurrencyCallback
{
public:
    DataLoadedCallback(task_completion_event<void> tce) :
        m_task_completion_event{ tce }
    {}

    void CurrencyDataLoadFinished(bool didLoad) override
    {
        m_task_completion_event.set();
    }

    void CurrencySymbolsCallback(_In_ const wstring& fromSymbol, _In_ const wstring& toSymbol) override {}
    void CurrencyRatiosCallback(_In_ const wstring& ratioEquality, _In_ const wstring& accRatioEquality) override {}
    void CurrencyTimestampCallback(_In_ const std::wstring& timestamp, bool isWeekOldData) override {}
    void NetworkBehaviorChanged(_In_ int newBehavior) override {}

private:
    Concurrency::task_completion_event<void> m_task_completion_event;
};

namespace CalculatorUnitTests
{
    constexpr auto sc_Language_EN = L"en-US";

    const UCM::Category CURRENCY_CATEGORY = { NavCategory::Serialize(ViewMode::Currency), L"Currency", false /*supportsNegative*/ };

    unique_ptr<CurrencyDataLoader> MakeLoaderWithResults(String^ staticResponse, String^ allRatiosResponse)
    {
        auto client = make_unique<MockCurrencyHttpClientWithResult>(staticResponse, allRatiosResponse);
        client->SetSourceCurrencyCode(StringReference(DefaultCurrencyCode.data()));
        return make_unique<CurrencyDataLoader>(move(client));
    }

    String^ SerializeContent(const vector<String^>& data)
    {
        String^ result = L"";
        String^ delimiter = CurrencyDataLoaderConstants::CacheDelimiter;
        for (String^ content : data)
        {
            result += (delimiter + content);
        }

        return result;
    }

    bool WriteToFileInLocalCacheFolder(String^ filename, String^ content)
    {
        try
        {
            StorageFolder^ localFolder = ApplicationData::Current->LocalCacheFolder;
            StorageFile^ file = create_task(localFolder->CreateFileAsync(filename, CreationCollisionOption::ReplaceExisting)).get();
            create_task(FileIO::WriteTextAsync(file, content)).wait();
            return true;
        }
        catch (Exception^ ex)
        {
            return false;
        }
    }

    bool DeleteFileFromLocalCacheFolder(String^ filename)
    {
        try
        {
            StorageFolder^ folder = ApplicationData::Current->LocalCacheFolder;
            IAsyncOperation<StorageFile^>^ fileOperation = folder->GetFileAsync(filename);
            StorageFile^ file = create_task(fileOperation).get();
            create_task(file->DeleteAsync()).get();
            return true;
        }
        catch (Platform::Exception^ ex)
        {
            // FileNotFoundException is a valid result
            return ex->HResult == HRESULT_FROM_WIN32(ERROR_FILE_NOT_FOUND);
        }
        catch (...)
        {
            return false;
        }
    }

    bool DeleteCurrencyCacheFiles()
    {
        try
        {
            bool deletedStaticData = DeleteFileFromLocalCacheFolder(CurrencyDataLoaderConstants::StaticDataFilename);
            bool deletedAllRatiosData = DeleteFileFromLocalCacheFolder(CurrencyDataLoaderConstants::AllRatiosDataFilename);

            return deletedStaticData && deletedAllRatiosData;
        }
        catch (...)
        {
            return false;
        }
    }

    void InsertToLocalSettings(String^ key, Object^ value)
    {
        ApplicationData::Current->LocalSettings->Values->Insert(key, value);
    }

    void RemoveFromLocalSettings(String^ key)
    {
        // Safe to call, even if the key does not exist.
        ApplicationData::Current->LocalSettings->Values->Remove(key);
    }

    void StandardCacheSetup()
    {
        // Insert current time so data is less than a day old.
        DateTime now = Utils::GetUniversalSystemTime();
        InsertToLocalSettings(CurrencyDataLoaderConstants::CacheTimestampKey, now);
        InsertToLocalSettings(CurrencyDataLoaderConstants::CacheLangcodeKey, StringReference(sc_Language_EN));

        VERIFY_IS_TRUE(DeleteCurrencyCacheFiles());

        VERIFY_IS_TRUE(WriteToFileInLocalCacheFolder(CurrencyDataLoaderConstants::StaticDataFilename, CurrencyHttpClient::GetRawStaticDataResponse()));
        VERIFY_IS_TRUE(WriteToFileInLocalCacheFolder(CurrencyDataLoaderConstants::AllRatiosDataFilename, CurrencyHttpClient::GetRawAllRatiosDataResponse()));
    }

    class CurrencyConverterLoadTests
    {
    public:
        TEST_CLASS(CurrencyConverterLoadTests);


        TEST_METHOD_SETUP(DeleteCacheFiles)
        {
            return DeleteCurrencyCacheFiles();
        }

        TEST_METHOD(LoadFromCache_Fail_NoCacheKey)
        {
            RemoveFromLocalSettings(CurrencyDataLoaderConstants::CacheTimestampKey);

            CurrencyDataLoader loader{ nullptr };

            bool didLoad = loader.TryLoadDataFromCacheAsync().get();

            VERIFY_IS_FALSE(didLoad);
            VERIFY_IS_FALSE(loader.LoadFinished());
            VERIFY_IS_FALSE(loader.LoadedFromCache());
        }

        TEST_METHOD(LoadFromCache_Fail_OlderThanADay)
        {
            // Insert 24 hours ago so data is considered stale.
            // This will cause the load from cache to fail.
            DateTime now = Utils::GetUniversalSystemTime();
            DateTime dayOld;
            dayOld.UniversalTime = now.UniversalTime - CurrencyDataLoaderConstants::DayDuration - 1;
            InsertToLocalSettings(CurrencyDataLoaderConstants::CacheTimestampKey, dayOld);

            CurrencyDataLoader loader{ nullptr };

            bool didLoad = loader.TryLoadDataFromCacheAsync().get();

            VERIFY_IS_FALSE(didLoad);
            VERIFY_IS_FALSE(loader.LoadFinished());
            VERIFY_IS_FALSE(loader.LoadedFromCache());
        }

        TEST_METHOD(LoadFromCache_Fail_StaticDataFileDoesNotExist)
        {
            // Insert current time so data is less than a day old.
            // This will cause the load to continue to attempt to load the file.
            DateTime now = Utils::GetUniversalSystemTime();
            InsertToLocalSettings(CurrencyDataLoaderConstants::CacheTimestampKey, now);

            VERIFY_IS_TRUE(DeleteFileFromLocalCacheFolder(CurrencyDataLoaderConstants::StaticDataFilename));
            VERIFY_IS_TRUE(WriteToFileInLocalCacheFolder(CurrencyDataLoaderConstants::AllRatiosDataFilename, CurrencyHttpClient::GetRawAllRatiosDataResponse()));

            CurrencyDataLoader loader{ nullptr };

            bool didLoad = loader.TryLoadDataFromCacheAsync().get();

            VERIFY_IS_FALSE(didLoad);
            VERIFY_IS_FALSE(loader.LoadFinished());
            VERIFY_IS_FALSE(loader.LoadedFromCache());
        }

        TEST_METHOD(LoadFromCache_Fail_AllRatiosDataFileDoesNotExist)
        {
            // Insert current time so data is less than a day old.
            // This will cause the load to continue to attempt to load the file.
            DateTime now = Utils::GetUniversalSystemTime();
            InsertToLocalSettings(CurrencyDataLoaderConstants::CacheTimestampKey, now);

            VERIFY_IS_TRUE(WriteToFileInLocalCacheFolder(CurrencyDataLoaderConstants::StaticDataFilename, CurrencyHttpClient::GetRawStaticDataResponse()));
            VERIFY_IS_TRUE(DeleteFileFromLocalCacheFolder(CurrencyDataLoaderConstants::AllRatiosDataFilename));

            CurrencyDataLoader loader{ nullptr };

            bool didLoad = loader.TryLoadDataFromCacheAsync().get();

            VERIFY_IS_FALSE(didLoad);
            VERIFY_IS_FALSE(loader.LoadFinished());
            VERIFY_IS_FALSE(loader.LoadedFromCache());
        }
        
        TEST_METHOD(LoadFromCache_Fail_ResponseLanguageChanged)
        {
            DateTime now = Utils::GetUniversalSystemTime();
            InsertToLocalSettings(CurrencyDataLoaderConstants::CacheTimestampKey, now);

            // Tests always use en-US as response language. Insert a different lang-code to fail the test.
            InsertToLocalSettings(CurrencyDataLoaderConstants::CacheLangcodeKey, L"ar-SA");

            VERIFY_IS_TRUE(WriteToFileInLocalCacheFolder(CurrencyDataLoaderConstants::StaticDataFilename, CurrencyHttpClient::GetRawStaticDataResponse()));
            VERIFY_IS_TRUE(DeleteFileFromLocalCacheFolder(CurrencyDataLoaderConstants::AllRatiosDataFilename));

            CurrencyDataLoader loader{ nullptr };

            bool didLoad = loader.TryLoadDataFromCacheAsync().get();

            VERIFY_IS_FALSE(didLoad);
            VERIFY_IS_FALSE(loader.LoadFinished());
            VERIFY_IS_FALSE(loader.LoadedFromCache());
        }

        TEST_METHOD(LoadFromCache_Success)
        {
            StandardCacheSetup();

            CurrencyDataLoader loader{ nullptr };

            bool didLoad = loader.TryLoadDataFromCacheAsync().get();

            VERIFY_IS_TRUE(didLoad);
            VERIFY_IS_TRUE(loader.LoadFinished());
            VERIFY_IS_TRUE(loader.LoadedFromCache());
        }

        TEST_METHOD(LoadFromWeb_Fail_ClientIsNullptr)
        {
            CurrencyDataLoader loader{ nullptr };

            bool didLoad = loader.TryLoadDataFromWebAsync().get();

            VERIFY_IS_FALSE(didLoad);
            VERIFY_IS_FALSE(loader.LoadFinished());
            VERIFY_IS_FALSE(loader.LoadedFromWeb());
        }

        TEST_METHOD(LoadFromWeb_Fail_WebException)
        {
            CurrencyDataLoader loader{ make_unique<MockCurrencyHttpClientThrowsException>() };

            bool didLoad = loader.TryLoadDataFromWebAsync().get();

            VERIFY_IS_FALSE(didLoad);
            VERIFY_IS_FALSE(loader.LoadFinished());
            VERIFY_IS_FALSE(loader.LoadedFromWeb());
        }

        TEST_METHOD(LoadFromWeb_Success)
        {
            String^ staticResponse = CurrencyHttpClient::GetRawStaticDataResponse();
            String^ allRatiosResponse = CurrencyHttpClient::GetRawAllRatiosDataResponse();
            unique_ptr<CurrencyDataLoader> loader = MakeLoaderWithResults(staticResponse, allRatiosResponse);

            bool didLoad = loader->TryLoadDataFromWebAsync().get();

            VERIFY_IS_TRUE(didLoad);
            VERIFY_IS_TRUE(loader->LoadFinished());
            VERIFY_IS_TRUE(loader->LoadedFromWeb());
        }

        TEST_METHOD(Load_Success_LoadedFromCache)
        {
            StandardCacheSetup();

            CurrencyDataLoader loader{ nullptr };

            auto data_loaded_event = task_completion_event<void>();
            loader.SetViewModelCallback(make_shared<DataLoadedCallback>(data_loaded_event));

            auto data_loaded_task = create_task(data_loaded_event);
            loader.LoadData();
            data_loaded_task.wait();

            VERIFY_IS_TRUE(loader.LoadFinished());
            VERIFY_IS_TRUE(loader.LoadedFromCache());
            VERIFY_IS_FALSE(loader.LoadedFromWeb());
        }

        TEST_METHOD(Load_Success_LoadedFromWeb)
        {
            // Insert 24 hours ago so data is considered stale.
            // This will cause the load from cache to fail.
            DateTime now = Utils::GetUniversalSystemTime();
            DateTime dayOld;
            dayOld.UniversalTime = now.UniversalTime - CurrencyDataLoaderConstants::DayDuration - 1;
            InsertToLocalSettings(CurrencyDataLoaderConstants::CacheTimestampKey, dayOld);

            String^ staticResponse = CurrencyHttpClient::GetRawStaticDataResponse();
            String^ allRatiosResponse = CurrencyHttpClient::GetRawAllRatiosDataResponse();
            unique_ptr<CurrencyDataLoader> loader = MakeLoaderWithResults(staticResponse, allRatiosResponse);

            auto data_loaded_event = task_completion_event<void>();
            loader->SetViewModelCallback(make_shared<DataLoadedCallback>(data_loaded_event));

            auto data_loaded_task = create_task(data_loaded_event);
            loader->LoadData();
            data_loaded_task.wait();

            VERIFY_IS_TRUE(loader->LoadFinished());
            VERIFY_IS_FALSE(loader->LoadedFromCache());
            VERIFY_IS_TRUE(loader->LoadedFromWeb());
        }
    };

    class CurrencyConverterUnitTests
    {
        TEST_CLASS(CurrencyConverterUnitTests);

        const UCM::Unit GetUnit(const vector<UCM::Unit>& unitList, const wstring& target)
        {
            return *find_if(begin(unitList), end(unitList), [&target](const UCM::Unit& u) { return u.abbreviation == target; });
        }

        TEST_METHOD(Loaded_LoadOrderedUnits)
        {
            StandardCacheSetup();

            CurrencyDataLoader loader{ nullptr };

            auto data_loaded_event = task_completion_event<void>();
            loader.SetViewModelCallback(make_shared<DataLoadedCallback>(data_loaded_event));

            auto data_loaded_task = create_task(data_loaded_event);
            loader.LoadData();
            data_loaded_task.wait();

            VERIFY_IS_TRUE(loader.LoadFinished());
            VERIFY_IS_TRUE(loader.LoadedFromCache());
            VERIFY_IS_FALSE(loader.LoadedFromWeb());

            vector<UCM::Unit> unitList = loader.LoadOrderedUnits(CURRENCY_CATEGORY);
            VERIFY_ARE_EQUAL(size_t{ 2 }, unitList.size());

            const UCM::Unit usdUnit = GetUnit(unitList, L"USD");
            const UCM::Unit eurUnit = GetUnit(unitList, L"EUR");

            VERIFY_ARE_EQUAL(StringReference(L"United States - Dollar"), ref new String(usdUnit.name.c_str()));
            VERIFY_ARE_EQUAL(StringReference(L"USD"), ref new String(usdUnit.abbreviation.c_str()));

            VERIFY_ARE_EQUAL(StringReference(L"Europe - Euro"), ref new String(eurUnit.name.c_str()));
            VERIFY_ARE_EQUAL(StringReference(L"EUR"), ref new String(eurUnit.abbreviation.c_str()));
        }

        TEST_METHOD(Loaded_LoadOrderedRatios)
        {
            StandardCacheSetup();

            CurrencyDataLoader loader{ nullptr };

            auto data_loaded_event = task_completion_event<void>();
            loader.SetViewModelCallback(make_shared<DataLoadedCallback>(data_loaded_event));

            auto data_loaded_task = create_task(data_loaded_event);
            loader.LoadData();
            data_loaded_task.wait();

            VERIFY_IS_TRUE(loader.LoadFinished());
            VERIFY_IS_TRUE(loader.LoadedFromCache());
            VERIFY_IS_FALSE(loader.LoadedFromWeb());

            vector<UCM::Unit> unitList = loader.LoadOrderedUnits(CURRENCY_CATEGORY);
            VERIFY_ARE_EQUAL(size_t{ 2 }, unitList.size());

            const UCM::Unit usdUnit = GetUnit(unitList, L"USD");
            const UCM::Unit eurUnit = GetUnit(unitList, L"EUR");

            unordered_map<UCM::Unit, UCM::ConversionData, UCM::UnitHash> ratios = loader.LoadOrderedRatios(usdUnit);
            VERIFY_ARE_EQUAL(size_t{ 2 }, ratios.size());

            UCM::ConversionData usdRatioData = ratios[usdUnit];
            VERIFY_IS_TRUE((std::abs(1.0 - usdRatioData.ratio) < 1e-1));

            UCM::ConversionData eurRatioData = ratios[eurUnit];
            VERIFY_IS_TRUE((std::abs(0.920503 - eurRatioData.ratio) < 1e-6));
        }

        TEST_METHOD(Loaded_GetCurrencySymbols_Valid)
        {
            StandardCacheSetup();

            CurrencyDataLoader loader{ nullptr };

            auto data_loaded_event = task_completion_event<void>();
            loader.SetViewModelCallback(make_shared<DataLoadedCallback>(data_loaded_event));

            auto data_loaded_task = create_task(data_loaded_event);
            loader.LoadData();
            data_loaded_task.wait();

            VERIFY_IS_TRUE(loader.LoadFinished());
            VERIFY_IS_TRUE(loader.LoadedFromCache());
            VERIFY_IS_FALSE(loader.LoadedFromWeb());

            vector<UCM::Unit> unitList = loader.LoadOrderedUnits(CURRENCY_CATEGORY);
            VERIFY_ARE_EQUAL(size_t{ 2 }, unitList.size());

            const UCM::Unit usdUnit = GetUnit(unitList, L"USD");
            const UCM::Unit eurUnit = GetUnit(unitList, L"EUR");

            const pair<wstring, wstring> symbols = loader.GetCurrencySymbols(usdUnit, eurUnit);

            VERIFY_ARE_EQUAL(ref new String(L"$"), StringReference(symbols.first.c_str()));
            VERIFY_ARE_EQUAL(ref new String(L"€"), StringReference(symbols.second.c_str()));
        }

        TEST_METHOD(Loaded_GetCurrencySymbols_Invalid)
        {
            StandardCacheSetup();

            CurrencyDataLoader loader{ nullptr };

            auto data_loaded_event = task_completion_event<void>();
            loader.SetViewModelCallback(make_shared<DataLoadedCallback>(data_loaded_event));

            auto data_loaded_task = create_task(data_loaded_event);
            loader.LoadData();
            data_loaded_task.wait();

            VERIFY_IS_TRUE(loader.LoadFinished());
            VERIFY_IS_TRUE(loader.LoadedFromCache());
            VERIFY_IS_FALSE(loader.LoadedFromWeb());

            const UCM::Unit fakeUnit1 = {
                1, L"fakeUnit1", L"FUD1", false, false, false
            };

            const UCM::Unit fakeUnit2 = {
                2, L"fakeUnit2", L"FUD2", false, false, false
            };

            pair<wstring, wstring> symbols = loader.GetCurrencySymbols(fakeUnit1, fakeUnit2);

            VERIFY_ARE_EQUAL(ref new String(L""), StringReference(symbols.first.c_str()));
            VERIFY_ARE_EQUAL(ref new String(L""), StringReference(symbols.second.c_str()));

            // Verify that when only one unit is valid, both symbols return as empty string.
            vector<UCM::Unit> unitList = loader.LoadOrderedUnits(CURRENCY_CATEGORY);
            VERIFY_ARE_EQUAL(size_t{ 2 }, unitList.size());

            const UCM::Unit usdUnit = GetUnit(unitList, L"USD");

            symbols = loader.GetCurrencySymbols(fakeUnit1, usdUnit);

            VERIFY_ARE_EQUAL(ref new String(L""), StringReference(symbols.first.c_str()));
            VERIFY_ARE_EQUAL(ref new String(L""), StringReference(symbols.second.c_str()));

            symbols = loader.GetCurrencySymbols(usdUnit, fakeUnit1);

            VERIFY_ARE_EQUAL(ref new String(L""), StringReference(symbols.first.c_str()));
            VERIFY_ARE_EQUAL(ref new String(L""), StringReference(symbols.second.c_str()));
        }

        TEST_METHOD(Loaded_GetCurrencyRatioEquality_Valid)
        {
            StandardCacheSetup();

            CurrencyDataLoader loader{ nullptr };

            auto data_loaded_event = task_completion_event<void>();
            loader.SetViewModelCallback(make_shared<DataLoadedCallback>(data_loaded_event));

            auto data_loaded_task = create_task(data_loaded_event);
            loader.LoadData();
            data_loaded_task.wait();

            VERIFY_IS_TRUE(loader.LoadFinished());
            VERIFY_IS_TRUE(loader.LoadedFromCache());
            VERIFY_IS_FALSE(loader.LoadedFromWeb());

            vector<UCM::Unit> unitList = loader.LoadOrderedUnits(CURRENCY_CATEGORY);
            VERIFY_ARE_EQUAL(size_t{ 2 }, unitList.size());

            const UCM::Unit usdUnit = GetUnit(unitList, L"USD");
            const UCM::Unit eurUnit = GetUnit(unitList, L"EUR");

            const pair<wstring, wstring> ratio = loader.GetCurrencyRatioEquality(usdUnit, eurUnit);

            VERIFY_ARE_EQUAL(ref new String(L"1 USD = 0.9205 EUR"), StringReference(ratio.first.c_str()));
            VERIFY_ARE_EQUAL(ref new String(L"1 United States Dollar = 0.9205 Europe Euro"), StringReference(ratio.second.c_str()));
        }

        TEST_METHOD(Loaded_GetCurrencyRatioEquality_Invalid)
        {
            StandardCacheSetup();

            CurrencyDataLoader loader{ nullptr };

            auto data_loaded_event = task_completion_event<void>();
            loader.SetViewModelCallback(make_shared<DataLoadedCallback>(data_loaded_event));

            auto data_loaded_task = create_task(data_loaded_event);
            loader.LoadData();
            data_loaded_task.wait();

            VERIFY_IS_TRUE(loader.LoadFinished());
            VERIFY_IS_TRUE(loader.LoadedFromCache());
            VERIFY_IS_FALSE(loader.LoadedFromWeb());

            const UCM::Unit fakeUnit1 = {
                1, L"fakeUnit1", L"fakeCountry1", L"FUD1", false, false, false
            };
            const UCM::Unit fakeUnit2 = {
                2, L"fakeUnit2", L"fakeCountry2", L"FUD2", false, false, false
            };

            pair<wstring, wstring> ratio = loader.GetCurrencyRatioEquality(fakeUnit1, fakeUnit2);

            VERIFY_ARE_EQUAL(ref new String(L""), StringReference(ratio.first.c_str()));
            VERIFY_ARE_EQUAL(ref new String(L""), StringReference(ratio.second.c_str()));

            // Verify that when only one unit is valid, both symbols return as empty string.
            vector<UCM::Unit> unitList = loader.LoadOrderedUnits(CURRENCY_CATEGORY);
            VERIFY_ARE_EQUAL(size_t{ 2 }, unitList.size());

            const UCM::Unit usdUnit = GetUnit(unitList, L"USD");

            ratio = loader.GetCurrencyRatioEquality(fakeUnit1, usdUnit);

            VERIFY_ARE_EQUAL(ref new String(L""), StringReference(ratio.first.c_str()));
            VERIFY_ARE_EQUAL(ref new String(L""), StringReference(ratio.second.c_str()));

            ratio = loader.GetCurrencyRatioEquality(usdUnit, fakeUnit1);

            VERIFY_ARE_EQUAL(ref new String(L""), StringReference(ratio.first.c_str()));
            VERIFY_ARE_EQUAL(ref new String(L""), StringReference(ratio.second.c_str()));
        }
    };
}