/// <summary>
/// invoke calculate NI method within the NI Calculator class. assign returned value into Inherited Total NI Amount property.
/// </summary>
/// <param name="payee"></param>
public override void CalculateNationalInsuranceDeduction(Payee payee)
{
var niCalculator = new NationalInsuranceCalculator(); //create new instance of Type NICalculator.
niCalculator.CalculateNIContribution(payee);
TotalNationalInsuranceAmount = Math.Round(niCalculator.TotalNIAnnualContribution, 2); //rounding the result into 2 decimal places.
}
/* need to calculate the weekly income (annual gross / 52).
* using that figure to logically place the person category of NI contribution rate.
* take annual gross minus the first-free £183 to move on to calculate the next NI contribution rate which is 12%, and so on...*/
//Method to calculate NI contribution with object of Type Payee passed-in.
public void CalculateNIContribution(Payee payee)
{
var grossAnnualIncome = payee.GrossAnnualSalary;
var grossWeeklyIncome = CalculateWeeklyIncome(grossAnnualIncome);
//List<decimal> remainingValueOfWeeklySalary = new List<decimal> { grossWeeklyIncome };
if (grossWeeklyIncome < niLowerPrimaryWeeklyThreshold)
{
TotalNIAnnualContribution = 0.00m;
System.Console.WriteLine("***** There is no contribution to be paid with your current earning *****");
}
else if (grossWeeklyIncome >= niLowerPrimaryWeeklyThreshold && grossWeeklyIncome <= niUpperPrimaryWeeklyThreshold)
{
var niWeeklyDeduction = (grossWeeklyIncome - niLowerPrimaryWeeklyThreshold) * 0.12m;
TotalNIAnnualContribution = CalculateNIAnnualDeduction(niWeeklyDeduction);
}
else if (grossWeeklyIncome > niUpperPrimaryWeeklyThreshold)
{
var niWeeklyDeduction = (grossWeeklyIncome - niLowerPrimaryWeeklyThreshold) * 0.02m;
TotalNIAnnualContribution = CalculateNIAnnualDeduction(niWeeklyDeduction);
}
}
public abstract void CalculateNationalInsuranceDeduction(Payee payee);
public abstract void CalculateTax(Payee payee);
/// <summary>
/// invoke calculate tax method within the taxCalculator class. assign returned value into Inherited TotalTaxAmount property.
/// </summary>
/// <param name="payee"></param>
public override void CalculateTax(Payee payee)
{
var taxCalculator = new TaxCalculator(); //create new instance of Type TaxCalculator.
TotalTaxAmount = Math.Round(taxCalculator.CalculateTax(payee), 2); //rounding the result into 2 decimal places.
}
public decimal CalculateTax(Payee payee)
{
/*another way to create calculation of tax using anonymous/undefined type - but to be investigated - basically you can use foreach loop to start the calculation method.*/
//var taxBands = new[]
//{
// new { Lower = 0m, Upper = 10999m, Rate = 0.0m },
// new { Lower = 11000m, Upper = 43000m, Rate = 0.2m },
// new { Lower = 43001m, Upper = 150000m, Rate = 0.4m },
// new { Lower = 150001m, Upper = decimal.MaxValue, Rate = 0.45m }
//};
//Console.WriteLine(taxBands[0].Lower);
decimal totalTaxDeduction = 0.00m; //variable to contain the addition of total tax deduction. initialised with 0.00.
decimal[] taxMinThresholdRate = { 0.00m, 12501m, 14586m, 25159m, 43431m, 150001m }; //array to hold the min thresholds value for each 6 bands of tax rate.
decimal[] taxMaxThresholdRate = { 12500m, 14585m, 25158m, 43430m, 150000m, 150000000.0m }; //array to hold the max thresholds value for each 6 bands of tax rate.
decimal[] taxPercentsRate = { 0.00m, 0.19m, 0.20m, 0.21m, 0.41m, 0.46m }; //array to hold the tax rate value for each 6 bands of tax rate.
List <decimal> remainingValueOfSalary = new List <decimal> {
payee.GrossAnnualSalary
}; //list (with initial of annual salary) withhold remaining salary for each tax bands calculation.
//iterate through (& calculate tax due) each tax bands and calculate total tax owned at the end.
for (int i = 0; i < taxPercentsRate.Length; i++)
{
//if users income within personal allowance then return 0 for the total tax deduction.
if (payee.GrossAnnualSalary >= 0 && payee.GrossAnnualSalary <= 12500)
{
Console.WriteLine("¬¬¬¬¬¬¬¬¬¬¬¬¬¬¬¬¬¬¬¬¬¬¬¬¬¬¬¬¬¬¬¬¬¬¬¬¬¬¬¬¬¬¬¬¬¬¬¬¬¬¬¬¬¬¬¬¬¬¬¬¬¬¬¬¬¬¬¬¬¬¬¬¬");
Console.WriteLine($"Your income is within '20-'21 personal allowance. 0% tax will be applied");
Console.WriteLine("¬¬¬¬¬¬¬¬¬¬¬¬¬¬¬¬¬¬¬¬¬¬¬¬¬¬¬¬¬¬¬¬¬¬¬¬¬¬¬¬¬¬¬¬¬¬¬¬¬¬¬¬¬¬¬¬¬¬¬¬¬¬¬¬¬¬¬¬¬¬¬¬¬");
return(totalTaxDeduction);
}
//if users income outwith personal allowance then calculate tax due & return the total tax deduction.
else if (payee.GrossAnnualSalary > 12500.00m)
{
decimal taxDeduction;
//as long the amount in the remaining salary if higher then the taxable amount in the next tax rate, calculate those taxes
if (remainingValueOfSalary[i] > taxMaxThresholdRate[i] - taxMinThresholdRate[i])
{
//calculate the current tax bracket from min & max thresholds multiply with current tax bracket rate. result in tax deduction for the current bracket.
taxDeduction = (taxMaxThresholdRate[i] - taxMinThresholdRate[i]) * taxPercentsRate[i];
Console.WriteLine($"Tax deduction for your earning between £{taxMinThresholdRate[i]} - £{taxMaxThresholdRate[i]} is £{taxDeduction}.");
//increment the value of current tax bracket tax deduction to the total tax deduction.
totalTaxDeduction += taxDeduction;
//get remaining value of salary (then add to remaining salary List to have value for next loop) before moving on to the next tax bracket.
remainingValueOfSalary.Add(remainingValueOfSalary[i] - (taxMaxThresholdRate[i] - taxMinThresholdRate[i]));
}
//else calculate the remaining salary after deduction with the last tax rate. add result to total tax deduction.
else if (remainingValueOfSalary[i] < taxMaxThresholdRate[i] - taxMinThresholdRate[i])
{
if (remainingValueOfSalary[i] == 0)
{
Console.WriteLine("¬¬¬¬¬¬¬¬¬¬¬¬¬¬¬¬¬¬¬¬¬¬¬¬¬¬¬¬¬¬¬¬¬¬¬¬¬¬¬¬¬¬¬¬¬¬¬¬¬¬¬¬¬¬¬¬¬¬¬¬¬¬¬¬¬¬¬¬¬¬¬¬¬");
break;
}
else
{
decimal taxOnLastRemainingSalary;
taxOnLastRemainingSalary = remainingValueOfSalary[i] * taxPercentsRate[i];
totalTaxDeduction += taxOnLastRemainingSalary;
Console.WriteLine($"Tax deduction for your last remainder salary of £{remainingValueOfSalary[i]} is £{taxOnLastRemainingSalary}.");
remainingValueOfSalary.Add(0); //last remaining salary should be zero.
}
}
}
}
return(totalTaxDeduction);
}
