Add changes needed to use this library in GeneXus BL

src/Common/Font.cs

@@ -1,21 +1,38 @@
 using System;
+using System.ComponentModel;
 using System.Collections.Concurrent;
 using System.Collections.Generic;
+using System.Diagnostics;
 using System.IO;
 using System.Linq;
 using System.Threading.Tasks;
 using SkiaSharp;
 
 namespace GeneXus.Drawing;
 
+[TypeConverter(typeof(FontConverter))]
 [Serializable]
 public class Font : IDisposable, ICloneable
 {
 	internal readonly FontFamily m_family;
 	internal readonly float m_size;
+	internal readonly string m_original;
 
-	internal readonly string m_original = null;
-
+	/// <summary>
+	/// Initializes a new System.Drawing.Font that uses the specified existing <see cref='Font'/>
+	/// and <see cref='FontStyle'/> enumeration.
+	/// </summary>
+	/// <param name="prototype">The existing <see cref='Font'/> from which to create the new <see cref='Font'/></param>
+	/// <param name="newStyle">
+	/// The <see cref='FontStyle'/> to apply to the new S<see cref='Font'/>. Multiple
+	/// values of the <see cref='FontStyle'/> enumeration can be combined with the OR operator.
+	/// </param>
+	public Font(Font prototype, FontStyle newStyle)
+	{
+		m_family = prototype.FontFamily;
+		// TODO set newStyle
+	}
+
 	/// <summary>
 	/// Initializes a new <see cref='Font'/> using the specified <see cref='Drawing.FontFamily'/> and size.
 	/// </summary>
@@ -29,12 +46,20 @@ public Font(FontFamily family, float size = 12)
 	/// Initializes a new <see cref='Font'/> using the specified family name and size.
 	/// </summary>
 	public Font(string familyName, float size = 12)
-		: this(SystemFonts.Select(f => f.m_family).FirstOrDefault(f => f.MatchFamily(familyName))
-			  ?? throw new ArgumentException("missing font family", nameof(familyName)), size)
+		: this(SystemFonts.Select(f => f.m_family).FirstOrDefault(ff => ff is SkiaFontFamily sff && sff.MatchFamily(familyName)) ?? new UnknownFontFamily(familyName), size)
 	{
 		m_original = familyName;
 	}
 
+	/// <summary>
+	/// Initializes a new <see cref='Font'/> using the specified family name, size, styl.
+	/// </summary>
+	public Font(string familyName, float size, FontStyle style, GraphicsUnit unit)
+		: this(familyName, size)
+	{
+		// TODO set style and unit
+	}
+
 	/// <summary>
 	///  Cleans up resources for this <see cref='Font'/>.
 	/// </summary>
@@ -45,7 +70,7 @@ public Font(string familyName, float size = 12)
 	/// </summary>
 	public override string ToString()
 	{
-		string suffix = m_family.m_index > 0 ? $"#{m_family.m_index}" : string.Empty;
+		string suffix = m_family is SkiaFontFamily { m_index: > 0 } sff ? $"#{sff.m_index}" : string.Empty;
 		return $"[{GetType().Name}: Name={Name}{suffix}, Size={Size}]";
 	}
 
@@ -69,16 +94,9 @@ public void Dispose()
 	#region IClonable
 
 	/// <summary>
-	///  Creates an exact copy of this <see cref='Font'/>.
+	/// Creates an exact copy of this <see cref='Font'/>.
 	/// </summary>
-	public object Clone()
-	{
-		var index = m_family.m_index;
-		var bytes = m_family.m_data.ToArray();
-		var data = SKData.CreateCopy(bytes);
-		var family = new FontFamily(data, index);
-		return new Font(family);
-	}
+	public object Clone() => new Font((FontFamily)m_family.Clone());
 
 	#endregion
 
@@ -88,19 +106,17 @@ public object Clone()
 	/// <summary>
 	/// Creates a <see cref='SKFont'/> with the coordinates of the specified <see cref='Font'/> .
 	/// </summary>
-	public static explicit operator SKFont(Font font) => font.m_family.GetFont(font.m_size);
+	public static explicit operator SKFont(Font font) => (font.m_family as SkiaFontFamily)?.GetFont(font.m_size);
 
 	#endregion
 
 
 	#region Properties
 
-	private SKFont m_font => m_family.GetFont(m_size);
-
 	/// <summary>
 	/// Gets the face name of this <see cref='Font'/>.
 	/// </summary>
-	public string Name => $"{m_family.Name} {m_family.Face}";
+	public string Name => m_family is SkiaFontFamily sff ? $"{sff.Name} {sff.Face}" : m_family.Name;
 
 	/// <summary>
 	/// Gets the name of the <see cref='Font'/> originally specified.
@@ -176,22 +192,24 @@ public FontStyle Style
 	/// <summary>
 	/// Gets a value that indicates whether this <see cref='Font'/> has the italic style applied.
 	/// </summary>
-	public bool Italic => m_family.m_typeface.IsItalic;
+	public bool Italic => m_family.IsItalic;
 
 	/// <summary>
 	/// Gets a value that indicates whether this <see cref='Font'/> is bold.
 	/// </summary>
-	public bool Bold => m_family.m_typeface.IsBold;
+	public bool Bold => m_family.IsBold;
 
+	private SKFontMetrics Metrics => m_family is SkiaFontFamily sff ? sff.GetFont(m_size).Metrics : new SKFontMetrics();
+
 	/// <summary>
 	/// Gets a value indicating whether this <see cref='Font'/> is underlined.
 	/// </summary>
-	public bool Underline => m_font.Metrics.UnderlineThickness > 0 && m_font.Metrics.UnderlinePosition == 0f;
+	public bool Underline => Metrics is { UnderlineThickness: > 0, UnderlinePosition: 0f };
 
 	/// <summary>
 	/// Gets a value indicating whether this <see cref='Font'/> is strikeout (has a line through it).
 	/// </summary>
-	public bool Strikeout => m_font.Metrics.StrikeoutThickness > 0 && m_font.Metrics.StrikeoutPosition == 0f;
+	public bool Strikeout => Metrics is { StrikeoutThickness: > 0, StrikeoutPosition: 0f };
 
 	/// <summary>
 	/// Gets a value indicating whether the <see cref='Font'/> is a member of SystemFonts.
@@ -217,8 +235,29 @@ public static ICollection<Font> SystemFonts
 		}
 	}
 
-	private static ICollection<Font> s_SystemFonts = null;
+	private static ICollection<Font> s_SystemFonts;
 
+	/// <summary>
+	/// Gets the em-size, in points, of this <see cref='Font'/>.
+	/// </summary>
+	/// <returns>The em-size, in points, of this <see cref='Font'/></returns>
+	[Browsable(false)]
+	public float SizeInPoints
+	{
+		get
+		{
+			// TODO calculate it for other units
+			Debug.Assert(Unit == GraphicsUnit.Point);
+			return Size;
+		}
+	}
+
+	/// <summary>
+	/// Gets the unit of measure for this <see cref='Font'/>.
+	/// </summary>
+	/// <returns>A <see cref='GraphicsUnit'/> that represents the unit of measure for this <see cref='Font'/>.</returns>
+	public GraphicsUnit Unit => GraphicsUnit.Point;
+
 	#endregion
 
 
@@ -227,7 +266,7 @@ public static ICollection<Font> SystemFonts
 	/// <summary>
 	/// Returns the line spacing of this <see cref='Font'/>.
 	/// </summary>
-	public float GetHeight() => m_font.Metrics.Descent - m_font.Metrics.Ascent + m_font.Metrics.Leading;
+	public float GetHeight() => Metrics.Descent - Metrics.Ascent + Metrics.Leading;
 
 	/// <summary>
 	/// Returns a <see cref='Font'/> collection in the specified location.
@@ -240,7 +279,7 @@ public static ICollection<Font> GetFonts(string location)
 		{
 			if (FONT_EXTENSIONS.Contains(Path.GetExtension(fontFile)))
 			{
-				var family = new FontFamily(fontFile);
+				var family = FontFamilyFactory.Create(fontFile);
 				var font = new Font(family);
 				fonts.Add(font);
 			}