/// <summary>
/// Checks and corrects mistakes in equation.
/// </summary>
/// <exception cref="EquationIsEmptyException">
/// The exception that is thrown when equation class has empty list of elements,
/// because given text is empty or correction of incorrectly written equation text left no elements in the equation.
/// </exception>
private void Integrity_Check()
{
Elements_Enumerator Equation_Rator = new Elements_Enumerator(Element_Colection);
Check_Integrity_Of_Equation_Begining(Equation_Rator);
if (Equation_Rator.MoveNext() == false)
{
IElement Even_Preious_Element = null;
do
{
Check_Integrity_Of_Current_Element(Equation_Rator, Even_Preious_Element);
Even_Preious_Element = Equation_Rator.Previous_Element;
} while (Equation_Rator.MoveNext() == false);
}
if (Element_Colection.Count < 1)
{
throw new EquationIsEmptyException();
}
while (Element_Colection[Element_Colection.Count - 1] is INot_At_The_End)
{
Element_Colection.RemoveAt(Element_Colection.Count - 1);
if (Element_Colection.Count < 1)
{
throw new EquationIsEmptyException();
}
}
}
/// <summary>
/// Removes wrong elements at the begining of the equation and returns number of removed elements.
/// </summary>
/// <param name="Equation_Rator"></param>
/// <exception cref="EquationIsEmptyException">
private int Check_Integrity_Of_Equation_Begining(Elements_Enumerator Equation_Rator)
{
int removed_Elements = 0;
if (Equation_Rator.MoveNext() == true)
{
throw new EquationIsEmptyException();
}
// If equation begings by operand[s] - removes it[them]
while (Equation_Rator.Current_Element is INot_At_the_Begining)
{
if (Element_Colection.RemoveAt(Equation_Rator.Current_Index) == false)
{
throw new EquationIsEmptyException();
}
removed_Elements++;
}
return(removed_Elements);
}
/// <summary>
/// Finds mistakes of given elements and correct them in custom way.
/// </summary>
/// <param name="Equation_Rator">Enumerator of current list.</param>
/// <param name="Even_Preious_Element">elemnt </param>
private void Check_Integrity_Of_Current_Element(Elements_Enumerator Equation_Rator, IElement Even_Preious_Element)
{
IElement Current_Element = Equation_Rator.Current_Element;
IElement Previous_Element = Equation_Rator.Previous_Element;
if (Even_Preious_Element is Bracket && Equation_Rator.Previous_Element is IOperand && Equation_Rator.Current_Element is Bracket)
{
if (Even_Preious_Element is Open_Bracket || Equation_Rator.Current_Element is Close_Bracket)
{
Element_Colection.RemoveAt(Equation_Rator.Current_Index);
Equation_Rator--;
Element_Colection.RemoveAt(Equation_Rator.Current_Index);
int removed_Elements = Check_Integrity_Of_Equation_Begining(
new Elements_Enumerator(Element_Colection));
for (int i = 0; i <= removed_Elements; i++)
{
Equation_Rator--;
}
}
}
else if (Current_Element is Open_Bracket && Previous_Element is INot_Outside_The_Open_Bracket)
{
Element_Colection.Insert(Equation_Rator.Current_Index, new Multiplication());
Equation_Rator--;
}
else if (Previous_Element is Operand && Current_Element is Operand)
{
Element_Colection.RemoveAt(Equation_Rator.Current_Index);
Equation_Rator--;
}
else if (Previous_Element is Open_Bracket && Current_Element is Close_Bracket)
{
Element_Colection.RemoveAt(Equation_Rator.Current_Index);
Equation_Rator--;
Element_Colection.RemoveAt(Equation_Rator.Current_Index);
Equation_Rator--;
}
else if (Previous_Element is Close_Bracket && Current_Element is INot_Outside_The_Close_Bracket)
{
Element_Colection.Insert(Equation_Rator.Current_Index, new Multiplication());
Equation_Rator--;
}
else if (Previous_Element is Open_Bracket && Current_Element is INot_Intside_Bracket)
{
Element_Colection.RemoveAt(Equation_Rator.Current_Index);
Equation_Rator--;
}
else if (Current_Element is Close_Bracket && Previous_Element is INot_Intside_Bracket)
{
Element_Colection.RemoveAt(Equation_Rator.Current_Index - 1);
Equation_Rator--;
}
}