unit Myc.Test.Trade.DataServer;

interface

uses
    System.SysUtils,
    System.Generics.Collections,
    DUnitX.TestFramework,
    Myc.Signals,
    Myc.Lazy,
    Myc.Futures,
    Myc.Trade.DataPoint,
    Myc.Trade.DataSeries,
    Myc.Trade.DataServer;

type
    // Test fixture for TDataServer and TAuraTABFileServer, focusing on data equivalence
    // with TDataSeries.LoadDataSeries.
    [TestFixture]
    [IgnoreMemoryLeaks(true)]
    TTest_TABFileServer_Equivalence = class(TObject)
    private
        FServer: IDataServer<TDataPoint<TAskBidItem>>;
    public
        [SetupFixture]
        procedure SetupFixture;
        [Setup]
        procedure Setup;
        [TearDown]
        procedure TearDown;
        [TearDownFixture]
        procedure TearDownFixture;

        [Test]
        procedure Test_ServerReturnsSameDataAs_LoadDataSeries;
    end;

implementation

uses
    Myc.TaskManager;

const
    // The reference data file for this test.
    C_TEST_FILENAME = '\\COFFEE\TickData\Pepperstone\GER40_2025_03.tab_zip';
    // The chunk size for fetching data from the server.
    C_MAX_FETCH = 200;

{ TTest_TABFileServer_Equivalence }

procedure TTest_TABFileServer_Equivalence.SetupFixture;
begin
    // TAskBid.ClearCache ensures a clean state for data series loading.
    TAskBid.ClearCache;
end;

procedure TTest_TABFileServer_Equivalence.TearDownFixture;
begin
    // Resets the global IsMemoryLow function pointer, if it was set for testing.
    IsMemoryLow := nil;
end;

procedure TTest_TABFileServer_Equivalence.Setup;
begin
    // Initializes the data server with a specific test file.
    FServer := TAuraTABFileServer.Create(C_TEST_FILENAME);
end;

procedure TTest_TABFileServer_Equivalence.TearDown;
begin
    // Releases the data server instance.
    FServer := nil;
    // Clears any cached data to prevent interference with subsequent tests.
    TAskBid.ClearCache;
end;

procedure TTest_TABFileServer_Equivalence.Test_ServerReturnsSameDataAs_LoadDataSeries;
var
    chunk: array[0..C_MAX_FETCH - 1] of TDataPoint<TAskBidItem>;
    Dst: TArray<TDataPoint<TAskBidItem>>;
    i: Int64;
begin
    // Loads the expected data directly using TAskBid.LoadDataSeries.WaitFor.
    var ExpectedData := TAskBid.LoadDataSeries(C_TEST_FILENAME).WaitFor;
    SetLength(Dst, Length(ExpectedData));

    var cnt: Int64 := 0;
    var n: Integer;
    // Fetches data chunks from the server until all data is retrieved or server indicates live data.
    while not FServer.IsLiveData.Value and (cnt < Length(Dst)) do
    begin
        n := FServer.GetChunk(chunk);
        if n > 0 then
            Move(chunk[0], dst[cnt], n * sizeof(TDataPoint<TAskBidItem>));
        inc(cnt, n);
    end;

    // --- Assertions ---

    // 1. Verify that the total number of records fetched from the server matches the expected count.
    Assert.AreEqual(Length(ExpectedData), cnt, 'Data record count mismatch');

    // 2. Verify that the content of each record is identical.
    // The loop checks every 1000th element for efficiency.
    for n := 0 to High(ExpectedData) div 1000 do
    begin
        i := n * 1000;
        Assert.AreEqual(ExpectedData[i].TimeStamp, Dst[i].Time, 'Timestamp mismatch');
        Assert.AreEqual(ExpectedData[i].Data.Ask, Dst[i].Data.Ask, 'Ask price mismatch');
        Assert.AreEqual(ExpectedData[i].Data.Bid, Dst[i].Data.Bid, 'Bid price mismatch');
    end;
end;

initialization
    // Registers the test fixture with DUnitX.
    TDUnitX.RegisterTestFixture(TTest_TABFileServer_Equivalence);
end.