//
// System.Drawing.Printing.PrinterUnitConvert
//
// Authors:
//      Martin Willemoes Hansen (mwh@sysrq.dk)
//      Herve Poussineau (hpoussineau@fr.st)
//
// (C) 2003 Martin Willemoes Hansen
//

namespace System.Drawing.Printing
{
	public sealed class PrinterUnitConvert
	{
		public static double Convert (double value,
					      PrinterUnit fromUnit,
					      PrinterUnit toUnit)
		{
			switch (fromUnit)
			{
				case PrinterUnit.Display:
					switch (toUnit)
					{
						case PrinterUnit.Display: return value;
						case PrinterUnit.ThousandthsOfAnInch: return value * 10;
						case PrinterUnit.HundredthsOfAMillimeter: return value * 2.54;
						case PrinterUnit.TenthsOfAMillimeter: return value * .254;
					}
					break;
				case PrinterUnit.ThousandthsOfAnInch:
					switch (toUnit)
					{
						case PrinterUnit.Display: return value / 10;
						case PrinterUnit.ThousandthsOfAnInch: return value;
						case PrinterUnit.HundredthsOfAMillimeter: return value * .254;
						case PrinterUnit.TenthsOfAMillimeter: return value * .0254;
					}
					break;
				case PrinterUnit.HundredthsOfAMillimeter:
					switch (toUnit)
					{
						case PrinterUnit.Display: return value / 2.54;
						case PrinterUnit.ThousandthsOfAnInch: return value / .254;
						case PrinterUnit.HundredthsOfAMillimeter: return value;
						case PrinterUnit.TenthsOfAMillimeter: return value / 10;
					}
					break;
				case PrinterUnit.TenthsOfAMillimeter:
					switch (toUnit)
					{
						case PrinterUnit.Display: return value / .254;
						case PrinterUnit.ThousandthsOfAnInch: return value / .0254;
						case PrinterUnit.HundredthsOfAMillimeter: return value * 10;
						case PrinterUnit.TenthsOfAMillimeter: return value;
					}
					break;
			}
			// should never happen
			throw new NotImplementedException();
		}

		public static int Convert (int value,
					   PrinterUnit fromUnit,
					   PrinterUnit toUnit)
		{
			return (int)Convert((double)value, fromUnit, toUnit);
		}

		public static Margins Convert (Margins value,
					       PrinterUnit fromUnit,
					       PrinterUnit toUnit)
		{
			return new Margins(
				Convert(value.Left, fromUnit, toUnit),
				Convert(value.Right, fromUnit, toUnit),
				Convert(value.Top, fromUnit, toUnit),
				Convert(value.Bottom, fromUnit, toUnit));
		}

		public static Point Convert (Point value,
					     PrinterUnit fromUnit,
					     PrinterUnit toUnit)
		{
			return new Point(
				Convert(value.X, fromUnit, toUnit),
				Convert(value.Y, fromUnit, toUnit));
		}

		public static Rectangle Convert (Rectangle value,
						 PrinterUnit fromUnit,
						 PrinterUnit toUnit)
		{
			return new Rectangle(
				Convert(value.X, fromUnit, toUnit),
				Convert(value.Y, fromUnit, toUnit),
				Convert(value.Width, fromUnit, toUnit),
				Convert(value.Height, fromUnit, toUnit));
		}

		public static Size Convert (Size value,
					    PrinterUnit fromUnit,
					    PrinterUnit toUnit)
		{
			return new Size(
				Convert(value.Width, fromUnit, toUnit),
				Convert(value.Height, fromUnit, toUnit));
		}
	}
}