unit Myc.TaskManager;

interface

uses
    System.SysUtils,
    Myc.Signals;

type
    IMycTaskManager = interface
        // TOD Dokumentation
        function CreateTask(const Gate: TState; const Proc: TProc): TSignal.TSubscription;

        // Waits for the operation associated with State to complete.
        // Must not be called from a worker thread of this factory.
        // After waiting, or if the state is already set, any first stored exception
        // from any worker thread of this factory will be re-raised in the calling (main) thread.
        // Raises ETaskException if called from within a worker thread.
        procedure WaitFor(State: TState.IState);
    end;

var
    TaskManager: IMycTaskManager;

procedure SetupTaskManagerMock;

implementation

uses
    System.Generics.Collections;

type
    TMycExecMock = class(TInterfacedObject, TSignal.ISubscriber)
    private
        FProc: TProc;
    public
        constructor Create(const AProc: TProc);
        function Notify: Boolean;
    end;

    TMycTaskManagerMock = class(TInterfacedObject, IMycTaskManager)
    public
        // IMycTaskManager
        function CreateTask(const Gate: TState; const Proc: TProc): TSignal.TSubscription;
        procedure WaitFor(State: TState.IState);

        constructor Create;
    end;

{ TMycExecMock }

constructor TMycExecMock.Create(const AProc: TProc);
begin
    inherited Create;
    FProc := AProc;
end;

function TMycExecMock.Notify: Boolean;
begin
    Result := Assigned(FProc);
    if Result then
    begin
        FProc();
        FProc := nil;
    end;
end;

{ TMycTaskManagerMock }

constructor TMycTaskManagerMock.Create;
begin
    inherited Create;
end;

function TMycTaskManagerMock.CreateTask(const Gate: TState; const Proc: TProc): TSignal.TSubscription;
begin
    Result := Gate.Signal.Subscribe(TMycExecMock.Create(Proc));
end;

procedure TMycTaskManagerMock.WaitFor(State: TState.IState);
begin
    Assert(State.IsSet);
end;

procedure SetupTaskManagerMock;
begin
    TaskManager := TMycTaskManagerMock.Create;
end;

end.