/// <summary>
/// Get the bases for tax calculations
/// </summary>
/// <param name="codes">The collection of tax codes.</param>
/// <param name="taxInStoreCurrency">if set to <c>true</c> [tax in store currency].</param>
/// <param name="calculateBasePrice">if set to <c>true</c> [Calculate the base price].</param>
/// <param name="calculationBase">The calculation base.</param>
/// <param name="limitBase">The limit base.</param>
protected virtual void GetBases(ReadOnlyCollection <TaxCode> codes,
bool taxInStoreCurrency,
bool calculateBasePrice,
out decimal calculationBase,
out decimal limitBase)
{
decimal basePrice = decimal.Zero;
if (calculateBasePrice)
{
basePrice = this.TaxIncludedInPrice ?
Provider.GetBasePriceForTaxIncluded(this.LineItem, codes) :
LineItem.NetAmountPerUnit;
}
//1. Get initial value for the Calculation Base
switch (this.TaxBase)
{
case TaxBase.PercentPerTax:
// Base is the amount of the other tax
switch (this.TaxLimitBase)
{
case TaxLimitBase.InvoiceWithoutVat:
case TaxLimitBase.InvoiceWithVat:
calculationBase = Math.Abs(this.CalculateTaxOnTax(this.LineItem.RetailTransaction));
break;
case TaxLimitBase.UnitWithoutVat:
case TaxLimitBase.UnitWithVat:
// if this tax's Limit is per-unit, then we need to convert the existing tax amounts from per-line to per-unit
decimal quantity = (this.LineItem.Quantity == decimal.Zero) ? decimal.One : this.LineItem.Quantity;
calculationBase = Math.Abs(this.CalculateTaxOnTax()) / Math.Abs(quantity);
break;
default:
calculationBase = Math.Abs(this.CalculateTaxOnTax());
break;
}
break;
case TaxBase.PercentPerGross:
// Base is the price + other taxes
calculationBase = basePrice;
// If the Limit base is NOT per-unit, then we need to factor in the line quanity
if (TaxLimitBase != TaxLimitBase.UnitWithoutVat && TaxLimitBase != TaxLimitBase.UnitWithVat)
{
calculationBase *= Math.Abs(this.LineItem.Quantity);
}
if (!string.IsNullOrEmpty(this.TaxOnTax))
{
// Base is the Price + the amount of a single other tax
calculationBase += Math.Abs(this.CalculateTaxOnTax());
}
else
{
// Base is the Price + all other taxes
calculationBase += Math.Abs(TaxCode.SumAllTaxAmounts(this.LineItem));
}
break;
case TaxBase.AmountByUnit:
calculationBase = AmountPerUnitCalculationBase;
break;
case TaxBase.PercentPerNet:
case TaxBase.PercentGrossOnNet:
default:
// Base is the Price
calculationBase = basePrice;
// If the Limit base is NOT per-unit, then we need to factor in the line quanity
if (TaxLimitBase != TaxLimitBase.UnitWithoutVat && TaxLimitBase != TaxLimitBase.UnitWithVat)
{
calculationBase *= Math.Abs(this.LineItem.Quantity);
}
break;
}
//3. Set Limit Base
if (this.TaxBase == TaxBase.AmountByUnit)
{
// Base for limits/intervals is base-quantity * price
limitBase = calculationBase * basePrice;
// Convert limit base to Tax currency, if different
if (!taxInStoreCurrency)
{
limitBase = TaxService.Tax.InternalApplication.Services.Currency.CurrencyToCurrency(
ApplicationSettings.Terminal.StoreCurrency,
this.Currency,
limitBase);
}
// If the tax is calculated in a different UOM, then convert if possible
// this is only applicable for lineItem taxes.
BaseSaleItem saleLineItem = this.LineItem as BaseSaleItem;
if (saleLineItem != null &&
!string.Equals(this.Unit, this.LineItem.SalesOrderUnitOfMeasure, StringComparison.OrdinalIgnoreCase))
{
UnitOfMeasureData uomData = new UnitOfMeasureData(
ApplicationSettings.Database.LocalConnection,
ApplicationSettings.Database.DATAAREAID,
ApplicationSettings.Terminal.StorePrimaryId,
TaxService.Tax.InternalApplication);
UnitQtyConversion uomConversion = uomData.GetUOMFactor(this.LineItem.SalesOrderUnitOfMeasure, this.Unit, saleLineItem);
calculationBase *= uomConversion.GetFactorForQty(this.LineItem.Quantity);
}
}
else
{
// Convert base to Tax currency, if different
if (!taxInStoreCurrency)
{
calculationBase = TaxService.Tax.InternalApplication.Services.Currency.CurrencyToCurrency(
ApplicationSettings.Terminal.StoreCurrency,
this.Currency,
calculationBase);
}
// Base for limits/intervals is same for Calculations
limitBase = calculationBase;
}
}
/// <summary>
/// Calculate the tax bases calculationBase and limitBase (which is zero for India).
/// </summary>
/// <param name="basePrice">The base price.</param>
/// <param name="taxInStoreCurrency">if set to <c>true</c> [tax in store currency].</param>
/// <param name="calculateBasePrice">if set to <c>true</c> [Calculate the base price].</param>
/// <param name="calculationBase">The calculation base.</param>
/// <param name="limitBase">The limit base.</param>
protected override void GetBases(ReadOnlyCollection <TaxCode> codes, bool taxInStoreCurrency, bool calculateBasePrice, out decimal calculationBase, out decimal limitBase)
{
limitBase = decimal.Zero;
// For amount by unit calculation base is just the quantity.
if (this.TaxBase == TaxBase.AmountByUnit)
{
calculationBase = LineItem.Quantity;
// If the tax is calculated in a different UOM, then convert if possible
// this is only applicable for lineItem taxes.
BaseSaleItem saleLineItem = this.LineItem as BaseSaleItem;
if (saleLineItem != null &&
!string.Equals(this.Unit, this.LineItem.SalesOrderUnitOfMeasure, StringComparison.OrdinalIgnoreCase))
{
UnitOfMeasureData uomData = new UnitOfMeasureData(
ApplicationSettings.Database.LocalConnection,
ApplicationSettings.Database.DATAAREAID,
ApplicationSettings.Terminal.StorePrimaryId,
TaxService.Tax.InternalApplication);
UnitQtyConversion uomConversion = uomData.GetUOMFactor(this.LineItem.SalesOrderUnitOfMeasure, this.Unit, saleLineItem);
calculationBase *= uomConversion.GetFactorForQty(this.LineItem.Quantity);
}
return;
}
// Determine the starting calculation base (includes the line price or not)
switch (Formula.TaxableBasis)
{
case TaxableBases.LineAmount:
calculationBase = this.LineItem.NetAmountWithAllInclusiveTaxPerUnit;
break;
case TaxableBases.MRP:
calculationBase = GetMRP();
break;
default:
calculationBase = decimal.Zero;
break;
}
if (this.TaxIncludedInPrice)
{
calculationBase = GetBasePriceForTaxIncluded(calculationBase, codes, Formula);
}
calculationBase *= Math.Abs(this.LineItem.Quantity);
// Calculation expression is of the form: +[BCD]+[CVD]+[E-CESS_CVD]+[PE-C_CVD]+[SHE-C_CVD]
// where the brackets are replaced with the delimiter char(164)
// and BCD, CVD ... are tax codes.
// The operator may be + - / *.
string[] tokens = Formula.ParseExpression();
for (int index = 1; index < tokens.Length; index += 2)
{
ITaxItem taxItem = (from line in this.LineItem.TaxLines
where line.TaxCode == tokens[index]
select line).FirstOrDefault();
if (taxItem != null)
{
this.IsTaxOnTax = true;
this.TaxCodesInFormula.Add(taxItem.TaxCode);
}
decimal amount = taxItem == null ? decimal.Zero : taxItem.Amount * Math.Sign(this.LineItem.Quantity);
switch (tokens[index - 1])
{
case "+":
calculationBase += amount;
break;
case "-":
calculationBase -= amount;
break;
case "*":
calculationBase *= amount;
break;
case "/":
calculationBase = (amount == decimal.Zero ? calculationBase : calculationBase /= amount);
break;
default:
NetTracer.Error("GetBases(): Invalid operator in formula. tokens[{0}]: {1}", index - 1, tokens[index - 1]);
System.Diagnostics.Debug.Fail("Invalid operator in formula");
break;
}
}
// Knock any abatement off of the taxable basis
calculationBase *= (100 - AbatementPercent) / 100;
}
