private void PerformTasks(TasksState <T> tasksState)
{
T task;
lock (tasksState)
{
if (!tasksState.TasksToDo.Any() && !tasksState.TasksInProgress.Any())
{
return;
}
task = FindTaskToDo(tasksState);
}
if (task == null)
{
if (tasksState.TasksInProgress.Any())
{
return;
}
throw new Exception("There are some tasks with dependencies that can't be satisfied.");
}
MoveTaskToInProgress(tasksState, task);
Task.Run(() => PerformTasks(tasksState));
PerformTaskAndTheTasksDependentOnIt(tasksState, task);
}
private static void MoveTaskToDone(TasksState <T> tasksState, T task)
{
lock (tasksState)
{
tasksState.TasksInProgress.Remove(task);
tasksState.DoneTasks.Add(task);
}
}
public void PerformTasks(IEnumerable <T> tasks)
{
var tasksState = new TasksState <T>
{
DoneTasks = new HashSet <T>(),
TasksToDo = new List <T>(tasks),
TasksInProgress = new HashSet <T>()
};
PerformTasks(tasksState);
}
private T FindTaskToDo(TasksState <T> tasksState)
{
foreach (var task in tasksState.TasksToDo)
{
var dependencies = _getDependenciesFunction(task);
if (dependencies == null || dependencies.All(d => tasksState.DoneTasks.Contains(d)))
{
return(task);
}
}
return(null);
}
private void PerformTaskAndTheTasksDependentOnIt(TasksState <T> tasksState, T task)
{
_performTaskFunction(task).ContinueWith(taskResult =>
{
if (!taskResult.Result)
{
return;
}
MoveTaskToDone(tasksState, task);
PerformTasks(tasksState);
}).Wait();
}