unit FirstStrategy;

interface

uses
    System.SysUtils,
    System.Generics.Collections,
    Myc.Signals,
    Myc.Lazy,
    Myc.TaskManager,
    Myc.Trade.Types,
    Myc.Trade.DataPoint,
    Myc.Trade.DataArray;

type
    TTimeframe = (M1, M5, H1, D);

    TMycGenericConverter<S, T> = class(TMycConverter<S, T>)
        type
            TConvertFunc = reference to function(const Value: S): T;
    private
        FFunc: TConvertFunc;
    protected
        function ProcessData(const Value: S): TState; override;
    public
        constructor Create(const AFunc: TConvertFunc);
    end;

    TTicksToTimeframe = class(TMycConverter<TArray<TDataPoint<TAskBidItem>>, TDataPoint<TOhlcItem>>)
    private
        FTimeframe: TTimeframe;
        // Stores the currently aggregating OHLC data.
        FCurrentBar: TDataPoint<TOhlcItem>;
        function GetBarStartTime(const TimeStamp: TDateTime; const Timeframe: TTimeframe): TDateTime;
        function GetCurrentBar: TDataPoint<TOhlcItem>;
        function GetTimeframe: TTimeframe;
    public
        constructor Create(const ATimeframe: TTimeframe);

        // Process new data. This is called concurrently and must not have side effects out of the scope of this class!
        function ProcessData(const Values: TArray<TDataPoint<TAskBidItem>>): TState; override;

        property CurrentBar: TDataPoint<TOhlcItem> read GetCurrentBar;
        property Timeframe: TTimeframe read GetTimeframe;
    end;

    TIndicator<S, T> = class(TMycConverter<S, T>)
    strict private
        FQueue: TQueue;
    protected
        function ProcessData(const Value: S): TState; override; final;
        function Calculate(const Value: S): T; virtual; abstract;
    end;

    TGenericIndicator<S, T> = class(TIndicator<S, T>)
    private
        FFunc: TFunc<S, T>;
    protected
        function Calculate(const Value: S): T; override; final;
    public
        constructor Create(const AFunc: TFunc<S, T>);
    end;

implementation

uses
    System.DateUtils,
    System.Math;

{ TTicksToTimeframe }

constructor TTicksToTimeframe.Create(const ATimeframe: TTimeframe);
begin
    inherited Create;
    FTimeframe := ATimeframe;
end;

function TTicksToTimeframe.GetBarStartTime(const TimeStamp: TDateTime; const Timeframe: TTimeframe): TDateTime;
begin
    // Align the time grid to UTC 0:00 using functions from System.DateUtils
    case Timeframe of
        M1: Result := RecodeSecond(RecodeMilliSecond(TimeStamp, 0), 0);
        M5: Result := RecodeMinute(RecodeSecond(RecodeMilliSecond(TimeStamp, 0), 0), MinuteOf(TimeStamp) - MinuteOf(TimeStamp) mod 5);
        H1: Result := RecodeMinute(RecodeSecond(RecodeMilliSecond(TimeStamp, 0), 0), 0);
        D: Result := StartOfTheDay(TimeStamp);
    else
        Result := 0;
    end;
end;

function TTicksToTimeframe.GetCurrentBar: TDataPoint<TOhlcItem>;
begin
    Result := FCurrentBar;
end;

function TTicksToTimeframe.GetTimeframe: TTimeframe;
begin
    Result := FTimeframe;
end;

function TTicksToTimeframe.ProcessData(const Values: TArray<TDataPoint<TAskBidItem>>): TState;
var
    point: TDataPoint<TAskBidItem>;
    midPrice: Single;
    barStartTime: TDateTime;
    lastBarTime: TDateTime;
    currentBar: TOhlcItem;
    states: TList<TState>;
begin
    states := TList<TState>.Create;
    try
        // Process each incoming data point
        for point in Values do
        begin
            midPrice := (point.Data.Ask + point.Data.Bid) / 2;

            // Update bar for the strategy's timeframe
            barStartTime := GetBarStartTime(point.Time, FTimeframe);
            lastBarTime := FCurrentBar.Time;

            if (barStartTime > lastBarTime) then
            begin
                // A new bar starts, so the previous one is now complete.
                if (lastBarTime > 0) then
                    states.Add(Broadcast(FCurrentBar));

                // Start a new bar, Volume is 1 because this is the first tick.
                currentBar := TOhlcItem.Create(midPrice, midPrice, midPrice, midPrice, 1);
                FCurrentBar.Data := currentBar;
                FCurrentBar.Time := barStartTime;
            end
            else
            begin
                // Update the currently aggregating bar
                currentBar := FCurrentBar.Data;
                currentBar.High := Max(currentBar.High, midPrice);
                currentBar.Low := Min(currentBar.Low, midPrice);
                currentBar.Close := midPrice;
                // Volume is the number of ticks needed to build the complete bar.
                currentBar.Volume := currentBar.Volume + 1;
                FCurrentBar.Data := currentBar;
            end;
        end;

        Result := TState.All(states.ToArray);
    finally
        states.Free;
    end;
end;

{ TMycGenericConverter<S, T> }

constructor TMycGenericConverter<S, T>.Create(const AFunc: TConvertFunc);
begin
    inherited Create;
    FFunc := AFunc;
end;

function TMycGenericConverter<S, T>.ProcessData(const Value: S): TState;
begin
    Result := Broadcast(FFunc(Value));
end;

function TIndicator<S, T>.ProcessData(const Value: S): TState;
begin
    Result := FQueue.Enqueue(function: TState begin Result := Broadcast(Calculate(Value)); end);
end;

constructor TGenericIndicator<S, T>.Create(const AFunc: TFunc<S, T>);
begin
    inherited Create;
    FFunc := AFunc;
end;

function TGenericIndicator<S, T>.Calculate(const Value: S): T;
begin
    Result := FFunc(Value);
end;

end.