/Spss/SpssNumericVariable.cs

namespace Spss {

	using System;

	using System.Diagnostics;

	using System.Collections.Generic;

	using System.Linq;



	/// <summary>

	/// Represents an SPSS data variable that stores numeric information.

	/// </summary>

	/// <remarks>

	/// Both integer and floating point numbers are handled through this

	/// class.

	/// </remarks>

	public class SpssNumericVariable : SpssVariable {

		private const int DecimalPlacesDefault = 0;

		private readonly SpssNumericVariableValueLabelsDictionary valueLabels;

		private FormatTypeCode writeFormat;

		private FormatTypeCode printFormat;

		private int writeWidth;

		private int printWidth;

		private int writeDecimal;

		private int printDecimal;



		/// <summary>

		/// Creates an instance of the <see cref="SpssNumericVariable"/> class,

		/// for use when defining a new variable.

		/// </summary>

		public SpssNumericVariable() {

			this.valueLabels = new SpssNumericVariableValueLabelsDictionary(this);

			this.WriteFormat = this.PrintFormat = FormatTypeCode.SPSS_FMT_F;

			this.WriteDecimal = this.PrintDecimal = DecimalPlacesDefault;

			this.WriteWidth = this.PrintWidth = ColumnWidthDefault;

			this.MissingValues = new List<double>(3);

		}



		/// <summary>

		/// Creates an instance of the <see cref="SpssNumericVariable"/> class,

		/// for use in loading variables from an existing SPSS data file.

		/// </summary>

		/// <param name="variables">The containing collection.</param>

		/// <param name="varName">The name of the variable.</param>

		/// <param name="writeFormat">The write format.  The default is <see cref="FormatTypeCode.SPSS_FMT_F"/></param>

		/// <param name="writeDecimal">The write decimal.</param>

		/// <param name="writeWidth">Width of the write.</param>

		/// <param name="printFormat">The print format.  The default is <see cref="FormatTypeCode.SPSS_FMT_F"/></param>

		/// <param name="printDecimal">The print decimal.</param>

		/// <param name="printWidth">Width of the print.</param>

		protected internal SpssNumericVariable(SpssVariablesCollection variables, string varName, FormatTypeCode writeFormat, int writeDecimal, int writeWidth, FormatTypeCode printFormat, int printDecimal, int printWidth)

			: base(variables, varName) {

			this.valueLabels = new SpssNumericVariableValueLabelsDictionary(this);



			MissingValueFormatCode formatCode;

			double[] missingValues = new double[3];

			ReturnCode result = SpssException.ThrowOnFailure(SpssSafeWrapper.spssGetVarNMissingValues(this.FileHandle, this.Name, out formatCode, out missingValues[0], out missingValues[1], out missingValues[2]), "spssGetVarNMissingValues");

			this.MissingValueFormat = formatCode;

			this.MissingValues = new List<double>(missingValues.Take(Math.Abs((int)formatCode)));

			this.writeDecimal = writeDecimal;

			this.writeWidth = writeWidth;

			this.writeFormat = writeFormat;

			this.printDecimal = printDecimal;

			this.printWidth = printWidth;

			this.printFormat = printFormat;

		}



		/// <summary>

		/// Gets or sets the missing values for this variable.

		/// </summary>

		/// <value>The missing values.</value>

		/// <remarks>

		/// A maximum of three maximum values may be supplied.

		/// </remarks>

		public IList<double> MissingValues { get; private set; }



		public MissingValueFormatCode MissingValueFormat { get; set; }



		/// <summary>

		/// Gets the SPSS type for the variable.

		/// </summary>

		public override int SpssType {

			get {

				return 0; // 0 = numeric to SPSS

			}

		}



		public virtual FormatTypeCode WriteFormat {

			get {

				return this.writeFormat;

			}



			set {

				if (!this.IsApplicableFormatTypeCode(value)) {

					throw new ArgumentOutOfRangeException("value", "This value does not apply to this type of SPSS variable.");

				}



				this.writeFormat = value;

			}

		}



		public virtual FormatTypeCode PrintFormat {

			get {

				return this.printFormat;

			}



			set {

				if (!this.IsApplicableFormatTypeCode(value)) {

					throw new ArgumentOutOfRangeException("value", "This value does not apply to this type of SPSS variable.");

				}



				this.printFormat = value;

			}

		}



		public int WriteWidth {

			get {

				return this.writeWidth;

			}



			set {

				if (value < 0) {

					throw new ArgumentOutOfRangeException("value");

				}



				this.writeWidth = value;

			}

		}



		public int PrintWidth {

			get {

				return this.printWidth;

			}



			set {

				if (value < 0) {

					throw new ArgumentOutOfRangeException("value");

				}



				this.printWidth = value;

			}

		}



		public int WriteDecimal {

			get {

				return this.writeDecimal;

			}



			set {

				if (value < 0) {

					throw new ArgumentOutOfRangeException("value");

				}



				this.writeDecimal = value;

			}

		}



		public int PrintDecimal {

			get {

				return this.printDecimal;

			}



			set {

				if (value < 0) {

					throw new ArgumentOutOfRangeException("value");

				}



				this.printDecimal = value;

			}

		}



		/// <summary>

		/// The set of value labels (response values and labels) that are defined.

		/// </summary>

		public IDictionary<double, string> ValueLabels {

			get { return this.valueLabels; }

		}



		/// <summary>

		/// Gets or sets the data value of this variable within a specific case.

		/// </summary>

		/// <remarks>

		/// Null values are translated to and from 

		/// <see cref="SpssDataDocument.SystemMissingValue"/> transparently.

		/// </remarks>

		internal new double? Value {

			get {

				double v;

				SpssException.ThrowOnFailure(SpssSafeWrapper.spssGetValueNumericImpl(FileHandle, Handle, out v), "spssGetValueNumeric");

				if (v == SpssDataDocument.SystemMissingValue)

					return null;

				return v;

			}



			set {

				if (!value.HasValue) value = SpssDataDocument.SystemMissingValue;

				SpssException.ThrowOnFailure(SpssSafeWrapper.spssSetValueNumeric(FileHandle, Handle, value.Value), "spssSetValueNumeric");

			}

		}



		/// <summary>

		/// Updates details of the variable.

		/// </summary>

		protected override void Update() {

			base.Update();



			if (!IsInCollection) {

				return; // we'll get to do this later

			}



			this.valueLabels.Update();

			double[] missingValues = new double[3];

			this.MissingValues.Take(missingValues.Length).ToArray().CopyTo(missingValues, 0);

			SpssException.ThrowOnFailure(SpssSafeWrapper.spssSetVarNMissingValues(

				this.FileHandle,

				this.Name,

				this.MissingValueFormat,

				missingValues[0],

				missingValues[1],

				missingValues[2]), "spssSetVarNMissingValues");



			SpssException.ThrowOnFailure(SpssSafeWrapper.spssSetVarPrintFormat(FileHandle, Name, this.PrintFormat, this.PrintDecimal, this.PrintWidth), "spssSetVarPrintFormat");

			SpssException.ThrowOnFailure(SpssSafeWrapper.spssSetVarWriteFormat(FileHandle, Name, this.WriteFormat, this.WriteDecimal, this.WriteWidth), "spssSetVarWriteFormat");

		}



		public override SpssVariable Clone() {

			SpssNumericVariable other = new SpssNumericVariable();

			CloneTo(other);

			return other;

		}



		protected override void CloneTo(SpssVariable spssVar) {

			base.CloneTo(spssVar);

			SpssNumericVariable other = spssVar as SpssNumericVariable;

			if (other == null) {

				throw new ArgumentException("Must be of type " + GetType().Name + ".", "other");

			}

			other.PrintDecimal = this.PrintDecimal;

			other.PrintFormat = this.PrintFormat;

			other.PrintWidth = this.PrintWidth;

			other.WriteDecimal = this.WriteDecimal;

			other.WriteFormat = this.WriteFormat;

			other.WriteWidth = this.WriteWidth;

			other.MissingValueFormat = this.MissingValueFormat;

			other.MissingValues = new List<double>(this.MissingValues);

			this.valueLabels.CopyTo(other.valueLabels);

		}



		protected override bool IsApplicableFormatTypeCode(FormatTypeCode formatType) {

			return formatType != FormatTypeCode.SPSS_FMT_A &&

				!SpssDateVariable.IsDateVariable(formatType);

		}

	}

}