void SimpleForwardPlanner()
{
Plan.Clear(); // we clear the plan before we start populating it
Stack <Task> tasks = new Stack <Task> ();
tasks.Push(new CaveMonsterCompoundTask()); // HTN ROOT
while (tasks.Count > 0)
{
Task task = tasks.Pop();
if (task.isCompound())
{
// then we can safely cast it
CompoundTask compoundTask = (CompoundTask)task;
// not all compound tasks need to find a task
if (compoundTask.NeedsToFindTask())
{
CompoundTask method = compoundTask.FindTask();
// if we found a task
if (method != null)
{
// CODE TO SAVE STATE HERE NOT NEEDED BECAUSE OF PRE CONDITIONS
// we push the subtasks into our tasks stack
foreach (Task t in method.GetSubtasks())
{
tasks.Push(t);
}
}
else
{
// if method == null
// CODE TO RESTORE STATE HERE
}
}
// if don't need to find task, then we just add all subtasks of the compoundtask to tasks
else
{
foreach (Task t in compoundTask.GetSubtasks())
{
tasks.Push(t);
}
}
} // ELSE task is primitive
else
{
// can safely cast
PrimitiveTask primitiveTask = (PrimitiveTask)task;
if (primitiveTask.ValidPreconditions())
{
// Also need to Update State but we will do that when we execute the primitive task, not here
Plan.Add(primitiveTask);
}
else
{
// if preconditions were false
// CODE TO RESTORE STATE HERE
}
}
}
hasPlan = true;
Plan.Reverse(); // because we built it bottom up
}
