unit TestDataArray;

interface

uses
    System.SysUtils,
    DUnitX.TestFramework,
    Myc.Data.Series;

type
    [TestFixture]
    TMyTestObject = class
    private
        function GenerateData(Count: Integer): TArray<Integer>;
    public
        [Test]
        [TestCase('Small_NoSlide', '100, -1')]
        [TestCase('Small_WithSlide', '100, 50')]
        [TestCase('Medium_NoSlide_CrossChunk', '1500, -1')]
        [TestCase('Medium_WithSlide_CrossChunk', '2500, 1500')]
        [TestCase('Large_ExactSlide', '5000, 1024')]
        procedure TestChunkArray_CreateFromArray(const DataSize, MaxCount: Integer);

        [Test]
        procedure TestChunkArray_Add_And_Slide;

        [Test]
        procedure TestChunkArray_Copy_IsIndependent;

        [Test]
        procedure TestSeries_CreationAndIndexing;

        [Test]
        procedure TestSeries_Add_And_Copy;
    end;

implementation

uses
    System.Generics.Collections;

{ TMyTestObject }

function TMyTestObject.GenerateData(Count: Integer): TArray<Integer>;
var
    i: Integer;
begin
    SetLength(Result, Count);
    for i := 0 to Count - 1 do
        Result[i] := i;
end;

procedure TMyTestObject.TestChunkArray_Add_And_Slide;
var
    arr: TChunkArray<Integer>;
    newData: TArray<Integer>;
begin
    // Test sliding with single additions
    arr := TChunkArray<Integer>.CreateFromArray([], 5); // MaxCount = 5

    arr.Add(10, 5); // arr = [10]
    Assert.AreEqual(1, arr.Count);
    Assert.AreEqual(10, arr[0]);

    arr.Add(20, 5); // arr = [10, 20]
    arr.Add(30, 5); // arr = [10, 20, 30]
    arr.Add(40, 5); // arr = [10, 20, 30, 40]
    arr.Add(50, 5); // arr = [10, 20, 30, 40, 50]
    Assert.AreEqual(5, arr.Count);
    Assert.AreEqual(10, arr[0]);
    Assert.AreEqual(50, arr[4]);

    // Now, slide the window
    arr.Add(60, 5); // arr becomes [20, 30, 40, 50, 60]
    Assert.AreEqual(5, arr.Count, 'Count should remain at MaxCount');
    Assert.AreEqual(20, arr[0], 'First item should be slided out');
    Assert.AreEqual(60, arr[4], 'Last item should be the new one');

    // Test sliding with array addition
    arr := TChunkArray<Integer>.CreateFromArray([1, 2, 3], 5); // arr = [1, 2, 3], MaxCount = 5
    newData := [4, 5, 6, 7];
    arr.Add(newData, 5); // arr becomes [3, 4, 5, 6, 7]
    Assert.AreEqual(5, arr.Count, 'Count should be MaxCount after adding array');
    Assert.AreEqual(3, arr[0]);
    Assert.AreEqual(7, arr[4]);
end;

procedure TMyTestObject.TestChunkArray_Copy_IsIndependent;
const
    DATA_SIZE = 3000; // Approx 3 chunks
    MAX_COUNT_COPY = 1500; // Partial copy
var
    original, fullCopy, partialCopy: TChunkArray<Integer>;
    data: TArray<Integer>;
    i: Integer;
begin
    data := GenerateData(DATA_SIZE);
    original := TChunkArray<Integer>.CreateFromArray(data, -1);

    // 1. Test full copy
    fullCopy := original.Copy(-1);
    Assert.AreEqual(original.Count, fullCopy.Count, 'Full copy count should match original');
    for i := 0 to original.Count - 1 do
        Assert.AreEqual(original[i], fullCopy[i], 'Full copy item should match original');

    // 2. Test partial copy
    partialCopy := original.Copy(MAX_COUNT_COPY);
    Assert.AreEqual(MAX_COUNT_COPY, partialCopy.Count, 'Partial copy should have MaxCount items');
    for i := 0 to partialCopy.Count - 1 do
        // The partial copy contains the LAST items of the original
        Assert.AreEqual(original[i + (DATA_SIZE - MAX_COUNT_COPY)], partialCopy[i], 'Partial copy item should match last part of original');

    // 3. Test independence after modification
    // Add an item to original. This modifies its last chunk.
    original.Add(9999, -1);
    Assert.AreEqual(DATA_SIZE + 1, original.Count, 'Original count should increment');

    // Verify the full copy is unchanged.
    Assert.AreEqual(DATA_SIZE, fullCopy.Count, 'Full copy count should NOT change');
    Assert.AreNotEqual(9999, fullCopy[fullCopy.Count - 1], 'Last item of full copy should NOT be the new item');
    Assert.AreEqual(data[DATA_SIZE - 1], fullCopy[fullCopy.Count - 1], 'Last item of full copy should be original last item');

    // Verify the partial copy is unchanged.
    Assert.AreEqual(MAX_COUNT_COPY, partialCopy.Count, 'Partial copy count should NOT change');
end;

procedure TMyTestObject.TestChunkArray_CreateFromArray(const DataSize, MaxCount: Integer);
var
    data, expectedData: TArray<Integer>;
    arr: TChunkArray<Integer>;
    effectiveCount: Integer;
    i: Integer;
begin
    data := GenerateData(DataSize);
    arr := TChunkArray<Integer>.CreateFromArray(data, MaxCount);

    if (MaxCount < 0) or (MaxCount >= DataSize) then
        effectiveCount := DataSize
    else
        effectiveCount := MaxCount;

    Assert.AreEqual(effectiveCount, arr.Count, 'Count should match effective count');

    if effectiveCount = 0 then
        exit;

    // We only expect the last 'effectiveCount' items from the original data
    SetLength(expectedData, effectiveCount);
    TArray.Copy<Integer>(data, expectedData, DataSize - effectiveCount, 0, effectiveCount);

    for i := 0 to effectiveCount - 1 do
        Assert.AreEqual(expectedData[i], arr.Items[i], 'Item at index should be correct');
end;

procedure TMyTestObject.TestSeries_Add_And_Copy;
var
    original, copy: TSeries<Integer>;
begin
    // 1. Create and add
    original := TSeries<Integer>.CreateFromArray([1, 2, 3], 5); // Lookback = 5
    Assert.AreEqual(Int64(3), original.TotalCount);

    original.Add(4, 5); // Series: [4, 3, 2, 1]
    original.Add(5, 5); // Series: [5, 4, 3, 2, 1]
    Assert.AreEqual(5, original.Count, 'Count should be 5');
    Assert.AreEqual(Int64(5), original.TotalCount, 'TotalCount should be 5');
    Assert.AreEqual(5, original[0], 'Index 0 should be 5');

    // 2. Test sliding
    original.Add(6, 5); // Series: [6, 5, 4, 3, 2]
    Assert.AreEqual(5, original.Count, 'Count should remain 5 after slide');
    Assert.AreEqual(Int64(6), original.TotalCount, 'TotalCount should be 6');
    Assert.AreEqual(6, original[0], 'Index 0 should be 6');
    Assert.AreEqual(2, original[4], 'Last item should be 2');

    // 3. Test copy
    copy := original.Copy();
    Assert.AreEqual(5, copy.Count, 'Copy count should match original count');
    Assert.AreEqual(Int64(5), copy.TotalCount, 'Copy TotalCount should match its own count, not original TotalCount');
    Assert.AreEqual(6, copy[0], 'Copy should have same data');

    // 4. Test independence
    original.Add(7, 5);
    Assert.AreEqual(7, original[0], 'Original should be updated');
    Assert.AreEqual(6, copy[0], 'Copy should NOT be updated');
end;

procedure TMyTestObject.TestSeries_CreationAndIndexing;
var
    series: TSeries<Integer>;
    data: TArray<Integer>;
begin
    data := [10, 20, 30, 40, 50];
    series := TSeries<Integer>.CreateFromArray(data, -1);

    Assert.AreEqual(5, series.Count, 'Series count should be 5');
    Assert.AreEqual(Int64(5), series.TotalCount, 'Series total count should be 5');

    // Test reversed indexing
    Assert.AreEqual(50, series[0], 'Index 0 should be the last element');
    Assert.AreEqual(40, series[1], 'Index 1 should be the second to last element');
    Assert.AreEqual(30, series[2]);
    Assert.AreEqual(20, series[3]);
    Assert.AreEqual(10, series[4], 'Last index should be the first element');
end;

initialization
    TDUnitX.RegisterTestFixture(TMyTestObject);

end.