/// <summary>
/// Execute a validated command by sending the message to an aggregate. If the command is valid, the command will be processed
/// by the aggregate. When the command has been handled successfully, and events are returned as a result, the events
/// are aggregated to create the next state of the viewmodel, by calling the user defined Update function.
/// Then a notification is sent to signal the state of the viewmodel has changed. This will trigger the component
/// to rerender, so that it can show the correct state in the user interface. This rerendering triggers the user defined View
/// function, which signifies how the view should be rendered
/// </summary>
/// <param name="target">The aggrgate that will handle the command</param>
/// <param name="command">The validate command that the aggregate will handle, if it is valid. </param>
/// <returns>When the command is not valid, it will return Some errors, None otherwise</returns>
protected async Task <Option <Error[]> > Dispatch(Aggregate <TCommand, TEvent> target, Validated <TCommand> command)
{
Result <CommandResult <TEvent>, Error[]> result = await target.Accept(command);
switch (result)
{
case Ok <CommandResult <TEvent>, Error[]>(var commandResult):
_shouldRender = commandResult.Events.Any();
ViewModel = Update(ViewModel, commandResult.Events);
StateHasChanged();
return(None <Error[]>());
case Error <CommandResult <TEvent>, Error[]>(var errors):
_shouldRender = true;
ViewModel.Errors = errors;
StateHasChanged();
return(Some(errors));
default:
_shouldRender = false;
throw new ArgumentOutOfRangeException(nameof(result));
}
}