/// <summary>
/// 连续弹出多个状态
/// </summary>
public void PopStates(int count)
{
if (count > _states.Count) count = _states.Count;
if (count <= 0) return;
if (_currentState != null)
{
_currentState.OnExit();
}
IStackState state;
while(count > 0)
{
state = _states.Pop();
if (state != null) state.OnPop();
count--;
}
state = _currentState;
_currentState = (_states.Count > 0) ? _states.Peek() : null;
_currentStateTime = 0f;
if (_currentState != null)
{
_currentState.OnEnter();
}
OnStateChanged(state, _currentState);
}
/// <summary>
/// 将新状态压入栈
/// </summary>
public void PushState(IStackState newState)
{
if (_currentState != null)
{
_currentState.OnExit();
}
Kit.Swap(ref _currentState, ref newState);
_currentStateTime = 0;
_states.Push(_currentState);
if (_currentState != null)
{
_currentState.OnPush();
_currentState.OnEnter();
}
OnStateChanged(newState, _currentState);
}
/// <summary>
/// Pulls the data sources from the provided stack state, and merges them with each stack slot.
/// </summary>
/// <param name="self">The state to modify.</param>
/// <param name="other">A snapshot of the stack to pull the data sources from.</param>
/// <returns><c>True</c> if the stack state has changed, <c>false</c> otherwise.</returns>
/// <exception cref="StackImbalanceException">Occurs when the stack states are of different size.</exception>
public static bool MergeWith <T>(this IStackState <SymbolicValue <T> > self, IStackState <SymbolicValue <T> > other)
{
if (self.Size != other.Size)
{
throw new StackImbalanceException();
}
var zipped = self
.GetAllStackSlots()
.Zip(other.GetAllStackSlots(), (a, b) => (a, b))
#if DEBUG
.ToArray()
#endif
;
bool changed = false;
foreach (var(a, b) in zipped)
{
changed |= a.MergeWith(b);
}
return(changed);
}
protected override void OnStateChanged(IStackState prevState, IStackState currentState)
{
focusTarget = (currentState as CustomStackState).rectTransform;
}
/// <summary>
/// Creates a new symbolic program state.
/// </summary>
/// <param name="programCounter">The value of the current program counter.</param>
/// <param name="stack">A snapshot of the current state of the stack.</param>
/// <param name="variables">A snapshot of the state of all variables.</param>
public SymbolicProgramState(long programCounter, IStackState <SymbolicValue <TInstruction> > stack, IVariableState <SymbolicValue <TInstruction> > variables)
{
ProgramCounter = programCounter;
Stack = stack ?? throw new ArgumentNullException(nameof(stack));
Variables = variables ?? throw new ArgumentNullException(nameof(variables));
}
/// <summary>
/// 状态变化后触发的事件
/// </summary>
protected virtual void OnStateChanged(IStackState prevState, IStackState currentState)
{
}
