Implemented Length type #63 (#68)

* added Length value object;

* added EF converter and tests;

* fixed typo;

* added changes related to PR comments;

* added unit tests for measurement related enum comparisson;

---------

Co-authored-by: Dejan Bratic <dejan.bratic@igwplc.com>

src/Nox.Types.EntityFramework/Types/Length/LengthConverter.cs

@@ -0,0 +1,12 @@
+using Microsoft.EntityFrameworkCore.Storage.ValueConversion;
+
+namespace Nox.Types.EntityFramework.Types;
+
+public class LengthToFootConverter : ValueConverter<Length, double>
+{
+    public LengthToFootConverter() : base(length => (double)length.ToFeet(), lengthValue => Length.FromFeet(lengthValue)) { }
+}
+public class LengthToMeterConverter : ValueConverter<Length, double>
+{
+    public LengthToMeterConverter() : base(length => (double)length.ToMeters(), lengthValue => Length.FromMeters(lengthValue)) { }
+}

src/Nox.Types/Common/MeasurementConversionFactor.cs

@@ -0,0 +1,37 @@
+using System;
+using System.Collections.Generic;
+
+namespace Nox.Common;
+
+internal sealed class MeasurementConversionFactor
+{
+    private static readonly Dictionary<(MeasurementTypeUnit, MeasurementTypeUnit), double> DefinedConversionFactors = new()
+    {
+        { (MeasurementTypeUnit.Foot, MeasurementTypeUnit.Meter), 0.30480000033},
+        { (MeasurementTypeUnit.Meter, MeasurementTypeUnit.Foot), 3.28083989142},
+        { (MeasurementTypeUnit.Kilometer, MeasurementTypeUnit.Mile), 0.62137119102},
+        { (MeasurementTypeUnit.Mile, MeasurementTypeUnit.Kilometer), 1.60934400315},
+        { (MeasurementTypeUnit.SquareFoot, MeasurementTypeUnit.SquareMeter), 0.09290304},
+        { (MeasurementTypeUnit.SquareMeter, MeasurementTypeUnit.SquareFoot), 10.76391042},
+    };
+
+    public double Value { get; }
+
+    public MeasurementConversionFactor(MeasurementTypeUnit sourceUnit, MeasurementTypeUnit targetUnit)
+    {
+        Value = ResolveConversionFactor(sourceUnit, targetUnit);
+    }
+
+    private static double ResolveConversionFactor(MeasurementTypeUnit sourceUnit, MeasurementTypeUnit targetUnit)
+    {
+        var conversion = (sourceUnit, targetUnit);
+
+        if (DefinedConversionFactors.ContainsKey(conversion))
+            return DefinedConversionFactors[conversion];
+
+        else if (sourceUnit == targetUnit)
+            return 1;
+
+        throw new NotImplementedException($"No conversion defined from {sourceUnit} to {targetUnit}.");
+    }
+}

src/Nox.Types/Common/MeasurementTypeUnit.cs

@@ -0,0 +1,14 @@
+namespace Nox.Common;
+
+internal enum MeasurementTypeUnit
+{
+    // Length
+    Foot = 1,
+    Meter = 2,
+    Kilometer = 3,
+    Mile = 4,
+
+    // Area
+    SquareFoot = 5,
+    SquareMeter = 6,
+}

src/Nox.Types/Nox.Types.csproj

@@ -21,5 +21,6 @@
     </PropertyGroup>
     <ItemGroup>
         <None Include="..\..\images\nox.png" Pack="true" PackagePath="" />
+		<InternalsVisibleTo Include="Nox.Types.Tests" />
     </ItemGroup>
 </Project>

src/Nox.Types/Types/Area/Area.cs

@@ -1,5 +1,7 @@
-using System;
+using Nox.Common;
+using System;
 using System.Collections.Generic;
+using System.Globalization;
 
 namespace Nox.Types;
 
@@ -91,7 +93,16 @@ internal override ValidationResult Validate()
         return result;
     }
 
-    public override string ToString() => $"{Value:G} {Unit.ToSymbol()}";
+    public override string ToString()
+        => $"{Value.ToString($"0.{new string('#', QuantityValueDecimalPrecision)}", CultureInfo.InvariantCulture)} {Unit.ToSymbol()}";
+
+    /// <summary>
+    /// Returns a string representation of the <see cref="Length"/> object using the specified <see cref="IFormatProvider"/>.
+    /// </summary>
+    /// <param name="formatProvider">The format provider for the length value.</param>
+    /// <returns>A string representation of the <see cref="Length"/> object with the value formatted using the specified <see cref="IFormatProvider"/>.</returns>
+    public string ToString(IFormatProvider formatProvider)
+        => $"{Value.ToString(formatProvider)} {Unit.ToSymbol()}";
 
     protected override IEnumerable<KeyValuePair<string, object>> GetEqualityComponents()
     {
@@ -104,18 +115,10 @@ protected override IEnumerable<KeyValuePair<string, object>> GetEqualityComponen
     private QuantityValue? _squareFeet;
     public QuantityValue ToSquareFeet() => (_squareFeet ??= GetAreaIn(AreaTypeUnit.SquareFoot));
 
-    private QuantityValue GetAreaIn(AreaTypeUnit unit)
+    private QuantityValue GetAreaIn(AreaTypeUnit targetUnit)
     {
-        if (Unit == unit)
-            return Round(Value);
-
-        else if (Unit == AreaTypeUnit.SquareMeter && unit == AreaTypeUnit.SquareFoot)
-            return Round(Value * 10.76391042);
-
-        else if (Unit == AreaTypeUnit.SquareFoot && unit == AreaTypeUnit.SquareMeter)
-            return Round(Value * 0.09290304);
-
-        throw new NotImplementedException($"No conversion defined from {Unit} to {unit}.");
+        var factor = new MeasurementConversionFactor((MeasurementTypeUnit)Unit, (MeasurementTypeUnit)targetUnit).Value;
+        return Round(Value * factor);
     }
 
     private static QuantityValue Round(QuantityValue value)

src/Nox.Types/Types/Area/AreaTypeUnit.cs

@@ -4,8 +4,8 @@ namespace Nox.Types;
 
 public enum AreaTypeUnit
 {
-    SquareFoot,
-    SquareMeter,
+    SquareFoot = 5,
+    SquareMeter = 6,
 }
 
 public static class AreaTypeUnitExtensions

src/Nox.Types/Types/Distance/Distance.cs

@@ -1,5 +1,7 @@
-using System;
+using Nox.Common;
+using System;
 using System.Collections.Generic;
+using System.Globalization;
 
 namespace Nox.Types;
 
@@ -112,7 +114,16 @@ protected override IEnumerable<KeyValuePair<string, object>> GetEqualityComponen
         yield return new KeyValuePair<string, object>(nameof(Value), ToKilometers());
     }
 
-    public override string ToString() => $"{Value:G} {Unit.ToSymbol()}";
+    public override string ToString()
+        => $"{Value.ToString($"0.{new string('#', QuantityValueDecimalPrecision)}", CultureInfo.InvariantCulture)} {Unit.ToSymbol()}";
+
+    /// <summary>
+    /// Returns a string representation of the <see cref="Length"/> object using the specified <see cref="IFormatProvider"/>.
+    /// </summary>
+    /// <param name="formatProvider">The format provider for the length value.</param>
+    /// <returns>A string representation of the <see cref="Length"/> object with the value formatted using the specified <see cref="IFormatProvider"/>.</returns>
+    public string ToString(IFormatProvider formatProvider)
+        => $"{Value.ToString(formatProvider)} {Unit.ToSymbol()}";
 
     private QuantityValue? _kilometers;
 
@@ -122,18 +133,10 @@ protected override IEnumerable<KeyValuePair<string, object>> GetEqualityComponen
 
     public QuantityValue ToMiles() => (_miles ??= GetDistanceIn(DistanceTypeUnit.Mile));
 
-    private QuantityValue GetDistanceIn(DistanceTypeUnit unit)
+    private QuantityValue GetDistanceIn(DistanceTypeUnit targetUnit)
     {
-        if (Unit == unit)
-            return Round(Value);
-
-        else if (Unit == DistanceTypeUnit.Kilometer && unit == DistanceTypeUnit.Mile)
-            return Round(Value * 0.62137119102);
-
-        else if (Unit == DistanceTypeUnit.Mile && unit == DistanceTypeUnit.Kilometer)
-            return Round(Value * 1.60934400315);
-
-        throw new NotImplementedException($"No conversion defined from {Unit} to {unit}.");
+        var factor = new MeasurementConversionFactor((MeasurementTypeUnit)Unit, (MeasurementTypeUnit)targetUnit).Value;
+        return Round(Value * factor);
     }
 
     private static QuantityValue Round(QuantityValue value)

src/Nox.Types/Types/Distance/DistanceTypeUnit.cs

@@ -4,8 +4,8 @@ namespace Nox.Types;
 
 public enum DistanceTypeUnit
 {
-    Kilometer,
-    Mile
+    Kilometer = 3,
+    Mile = 4,
 }
 
 public static class DistanceTypeUnitExtensions

src/Nox.Types/Types/Length/Length.cs

@@ -1,9 +1,126 @@
+using Nox.Common;
+using System;
+using System.Collections.Generic;
+using System.Globalization;
+
 namespace Nox.Types;
 
+/// <summary>
+/// Represents a Nox <see cref="Length"/> type and value object.
+/// </summary>
+public sealed class Length : ValueObject<QuantityValue, Length>
+{
+    private const int QuantityValueDecimalPrecision = 6;
+
+    public LengthTypeUnit Unit { get; private set; } = LengthTypeUnit.Meter;
+
+    public Length() { Value = 0; }
+
+    /// <summary>
+    /// Creates a new instance of <see cref="Length"/> object in meters.
+    /// </summary>
+    /// <param name="value">The value to create the <see cref="Length"/> with</param>
+    /// <returns></returns>
+    /// <exception cref="TypeValidationException"></exception>
+    public static Length FromMeters(QuantityValue value)
+        => From(value, LengthTypeUnit.Meter);
+
+    /// <summary>
+    /// Creates a new instance of <see cref="Length"/> object in feet.
+    /// </summary>
+    /// <param name="value">The origin value to create the <see cref="Length"/> with</param>
+    /// <returns></returns>
+    /// <exception cref="TypeValidationException"></exception>
+    public static Length FromFeet(QuantityValue value)
+        => From(value, LengthTypeUnit.Foot);
+
     /// <summary>
-    /// Represents a Nox <see cref="Length"/> type and value object.
+    /// Creates a new instance of <see cref="Length"/> object in meters.
     /// </summary>
-    /// <remarks>Placeholder, needs to be implemented</remarks>
-    public sealed class Length : ValueObject<QuantityValue, Length>
+    /// <param name="value">The value to create the <see cref="Length"/> with</param>
+    /// <returns></returns>
+    /// <exception cref="TypeValidationException"></exception>
+    public new static Length From(QuantityValue value)
+        => From(value, LengthTypeUnit.Meter);
+
+    /// <summary>
+    /// Creates a new instance of <see cref="Length"/> object with the specified <see cref="LengthTypeUnit"/>.
+    /// </summary>
+    /// <param name="value">The value to create the <see cref="Length"/> with</param>
+    /// <param name="unit">The <see cref="LengthTypeUnit"/> to create the <see cref="Length"/> with</param>
+    /// <returns></returns>
+    /// <exception cref="TypeValidationException"></exception>
+    public static Length From(QuantityValue value, LengthTypeUnit unit)
     {
+        var newObject = new Length
+        {
+            Value = Round(value),
+            Unit = unit,
+        };
+
+        var validationResult = newObject.Validate();
+
+        if (!validationResult.IsValid)
+        {
+            throw new TypeValidationException(validationResult.Errors);
+        }
+
+        return newObject;
     }
+
+    /// <summary>
+    /// Validates a <see cref="Length"/> object.
+    /// </summary>
+    /// <returns>true if the <see cref="Length"/> value is valid.</returns>
+    internal override ValidationResult Validate()
+    {
+        var result = Value.Validate();
+
+        if (Value < 0 && !double.IsNaN((double)Value) && !double.IsInfinity((double)Value))
+        {
+            result.Errors.Add(new ValidationFailure(nameof(Value), $"Could not create a Nox Length type as negative length value {Value} is not allowed."));
+        }
+
+        if (!Enum.IsDefined(typeof(LengthTypeUnit), Unit))
+        {
+            result.Errors.Add(new ValidationFailure(nameof(Unit), $"Could not create a Nox Length type as unit {Unit} is not supported."));
+        }
+
+        return result;
+    }
+
+    protected override IEnumerable<KeyValuePair<string, object>> GetEqualityComponents()
+    {
+        yield return new KeyValuePair<string, object>(nameof(Value), ToMeters());
+    }
+
+    public override string ToString()
+        => $"{Value.ToString($"0.{new string('#', QuantityValueDecimalPrecision)}", CultureInfo.InvariantCulture)} {Unit.ToSymbol()}";
+
+    /// <summary>
+    /// Returns a string representation of the <see cref="Length"/> object using the specified <see cref="IFormatProvider"/>.
+    /// </summary>
+    /// <param name="formatProvider">The format provider for the length value.</param>
+    /// <returns>A string representation of the <see cref="Length"/> object with the value formatted using the specified <see cref="IFormatProvider"/>.</returns>
+    public string ToString(IFormatProvider formatProvider)
+        => $"{Value.ToString(formatProvider)} {Unit.ToSymbol()}";
+
+    private QuantityValue? _meters;
+
+    public QuantityValue ToMeters()
+        => (_meters ??= GetLengthIn(LengthTypeUnit.Meter));
+
+    private QuantityValue? _feet;
+
+    public QuantityValue ToFeet()
+        => (_feet ??= GetLengthIn(LengthTypeUnit.Foot));
+
+    private QuantityValue GetLengthIn(LengthTypeUnit targetUnit)
+    {
+        var factor = new MeasurementConversionFactor((MeasurementTypeUnit)Unit, (MeasurementTypeUnit)targetUnit).Value;
+        return Round(Value * factor);
+    }
+
+    private static QuantityValue Round(QuantityValue value)
+        => Math.Round((double)value, QuantityValueDecimalPrecision);
+}

src/Nox.Types/Types/Length/LengthTypeUnit.cs

@@ -0,0 +1,22 @@
+using System;
+
+namespace Nox.Types;
+
+public enum LengthTypeUnit
+{
+    Foot = 1,
+    Meter = 2,
+}
+
+public static class LengthTypeUnitExtensions
+{
+    public static string ToSymbol(this LengthTypeUnit unit)
+    {
+        return unit switch
+        {
+            LengthTypeUnit.Foot => "ft",
+            LengthTypeUnit.Meter => "m",
+            _ => throw new NotImplementedException($"No symbol defined for unit {unit}.")
+        };
+    }
+}