/// <summary>
/// 四則運算事件
/// </summary>
/// <param name="newNumber">待處理數字</param>
/// <param name="nextOperator">下次要執行的運算子</param>
public void OperateEvent(NumberField newNumber, IOperator nextOperator)
{
//RightNumber一定會變null
//無限大時，Expression的處理被Compute負責了(?)
if (newNumber.isInput == false)
{
//如果等號後input, LeftNumber不變，並將RightNumber清空
RightNumber = null;
Operator = nextOperator;
}
else if (LeftNumber == null && Operator != null && RightNumber != null)
{
//等號後Input + Interrupt的狀況
LeftNumber = newNumber;
Operator = nextOperator;
RightNumber = null;
}
else if (LeftNumber == null && Operator == null && RightNumber == null)
{
//第一次輸進數字，不做運算
LeftNumber = newNumber;
Operator = nextOperator;
}
else if (LeftNumber != null && Operator != null && RightNumber == null)
{
//左數 四則運算 右數
LeftNumber = Compute(LeftNumber, newNumber);
Operator = nextOperator;
}
else if (LeftNumber != null && Operator != null && RightNumber != null)
{
//negate case
LeftNumber = newNumber;
Operator = nextOperator;
RightNumber = null;
}
//這個階段若LeftNumber.NaN 為true ，代表除到0了
if (!LeftNumber.NaN)
{
Expression = $"{LeftNumber.ToString()} {nextOperator.Mark()}";
}
//無限大處理，後續還未做
if (LeftNumber.NaN)
{
Expression += $" 0 {Operator.Mark()}";
}
}