' com/decimal.ab

#require <oleauto.ab>
#require <com/variant.ab>

Class Decimal
Public
	Sub Decimal(ByRef d As Decimal)
		dec = d
	End Sub

	Const Function Operator +() As Decimal
		Return New Decimal(dec)
	End Function

	Const Function Operator -() As Decimal
		Dim ret = New Decimal
		VarDecNeg(This.dec, ret.dec)
		Return ret
	End Function

	Const Function Operator *(y As Decimal) As Decimal
		Dim ret = New Decimal
		VarDecMul(This.dec, y.dec, ret.dec)
		Return ret
	End Function

	Const Function Operator *(y As Long) As Decimal
		Dim ret = New Decimal
		VarDecMulI4(This.dec, y, ret.dec)
		Return ret
	End Function

	Const Function Operator *(y As Int64) As Decimal
		Dim ret = New Decimal
		VarDecMulI8(This.dec, y, ret.dec)
		Return ret
	End Function

	Const Function Operator /(y As Decimal) As Decimal
		Dim ret = New Decimal
		VarDecDiv(This.dec, y.dec, ret.dec)
		Return ret
	End Function

	Const Function Operator +(y As Decimal) As Decimal
		Dim ret = New Decimal
		VarDecAdd(This.dec, y.dec, ret.dec)
		Return ret
	End Function

	Const Function Operator -(y As Decimal) As Decimal
		Dim ret = New Decimal
		VarDecSub(This.dec, y.dec, ret.dec)
		Return ret
	End Function

	Static Function Compare(x As Decimal, y As Decimal) As HRESULT
		Return VarDecCmp(x, y)
	End Function

	Static Function Compare(x As Decimal, y As Double) As HRESULT
		Return VarDecCmpR8(x, y)
	End Function

	Static Function Compare(x As Double, y As Decimal) As HRESULT
		Dim ret = VarDecCmpR8(y, x)
		Select Case ret
			Case VARCMP_LT
				Return VARCMP_GT
			Case VARCMP_GT
				Return VARCMP_LT
			Case Else
				Return ret
		End Select
	End Function

	Const Function Operator ==(y As Decimal) As Boolean
		Dim c = Compare(This, y)
		Return c = VARCMP_EQ
	End Function

	Const Function Operator ==(y As Double) As Boolean
		Dim c = Compare(This, y)
		Return c = VARCMP_EQ
	End Function

	Const Function Operator <>(y As Decimal) As Boolean
		Dim c = Compare(This, y)
		Return c <> VARCMP_EQ
	End Function

	Const Function Operator <>(y As Double) As Boolean
		Dim c = Compare(This, y)
		Return c <> VARCMP_EQ
	End Function

	Const Function Operator <(y As Decimal) As Boolean
		Dim c = Compare(This, y)
		Return c = VARCMP_LT
	End Function

	Const Function Operator <(y As Double) As Boolean
		Dim c = Compare(This, y)
		Return c = VARCMP_LT
	End Function
/*
	Const Function Operator >(y As Decimal) As Boolean
		Dim c = Compare(This, y)
		Return c = VARCMP_GT
	End Function

	Const Function Operator >(y As Double) As Boolean
		Dim c = Compare(This, y)
		Return c = VARCMP_GT
	End Function
*/
	Const Function Operator <=(y As Decimal) As Boolean
		Dim c = Compare(This, y)
		Return result = VARCMP_LT Or result = VARCMP_EQ
	End Function

	Const Function Operator <=(y As Double) As Boolean
		Dim c = Compare(This, y)
		Return result = VARCMP_LT Or result = VARCMP_EQ
	End Function

	Const Function Operator >=(y As Decimal) As Boolean
		Dim c = Compare(This, y)
		Return result = VARCMP_GT Or result = VARCMP_EQ
	End Function

	Const Function Operator >=(y As Double) As Boolean
		Dim c = Compare(This, y)
		Return result = VARCMP_GT Or result = VARCMP_EQ
	End Function

	Const Function Abs() As Decimal
		Abs = New Decimal
		VarDecAbs(This.dec, Abs.dec)
	End Function

	Const Function Fix() As Decimal
		Fix = New Decimal
		VarDecFix(This.dec, Fix.dec)
	End Function

	Const Function Int() As Decimal
		Int = New Decimal
		VarDecInt(This.dec, Int.dec)
	End Function

	Const Function Round(c = 0 As Long) As Decimal
		Round = New Decimal
		VarDecRound(This.dec, c, Round.dec)
	End Function

	Const Function Dec() As DECIMAL
		Return dec
	End Function

	Sub Dec(ByRef d As DECIMAL)
		dec = d
	End Sub

	Const Function ToVariant() As Variant
		Return New Variant(dec)
	End Function

	Override Function ToString() As String
		Dim bs As BSTR
		VarBstrFromDec(dec, LOCALE_USER_DEFAULT, LOCALE_USE_NLS, bs)
		ToString = New String(bs As PCWSTR, SysStringLen(bs) As Long)
		SysFreeString(bs)
	End Function

	Override Function GetHashCode() As Long
		Dim p = VarPtr(dec) As *DWord
		Return (p[0] Xor p[1] Xor p[2] Xor p[3]) As Long
	End Function

	Function Equals(y As Decimal) As Boolean
		Dim c = Compare(This, y)
		Return c = VARCMP_EQ
	End Function
Private
	dec As DECIMAL
End Class