From 6d5de6e912f53c121a5906cfb8a08b34300f36f3 Mon Sep 17 00:00:00 2001
From: Sergiusz Zalewski <38229504+KeterSCP@users.noreply.github.com>
Date: Thu, 9 Nov 2023 20:38:46 +0100
Subject: [PATCH] EMR_DELETEOBJECT

---
 SharpEmf.sln.DotSettings                      |  1 +
 src/SharpEmf/Enums/EmfRecordType.cs           |  5 +++
 .../Records/EnhancedMetafileRecord.cs         |  1 +
 .../ObjectManipulation/EmrDeleteObject.cs     | 43 +++++++++++++++++++
 4 files changed, 50 insertions(+)
 create mode 100644 src/SharpEmf/Records/ObjectManipulation/EmrDeleteObject.cs

diff --git a/SharpEmf.sln.DotSettings b/SharpEmf.sln.DotSettings
index 85b515d..73d801c 100644
--- a/SharpEmf.sln.DotSettings
+++ b/SharpEmf.sln.DotSettings
@@ -10,6 +10,7 @@
 	<s:Boolean x:Key="/Default/UserDictionary/Words/=CHECKPNGFORMAT/@EntryIndexedValue">True</s:Boolean>
 	<s:Boolean x:Key="/Default/UserDictionary/Words/=CLOSECHANNEL/@EntryIndexedValue">True</s:Boolean>
 	<s:Boolean x:Key="/Default/UserDictionary/Words/=CLOSEFIGURE/@EntryIndexedValue">True</s:Boolean>
+	<s:Boolean x:Key="/Default/UserDictionary/Words/=DELETEOBJECT/@EntryIndexedValue">True</s:Boolean>
 	<s:Boolean x:Key="/Default/UserDictionary/Words/=DOWNLOADFACE/@EntryIndexedValue">True</s:Boolean>
 	<s:Boolean x:Key="/Default/UserDictionary/Words/=DOWNLOADHEADER/@EntryIndexedValue">True</s:Boolean>
 	<s:Boolean x:Key="/Default/UserDictionary/Words/=DRAFTMODE/@EntryIndexedValue">True</s:Boolean>
diff --git a/src/SharpEmf/Enums/EmfRecordType.cs b/src/SharpEmf/Enums/EmfRecordType.cs
index 21e12e0..741a4fa 100644
--- a/src/SharpEmf/Enums/EmfRecordType.cs
+++ b/src/SharpEmf/Enums/EmfRecordType.cs
@@ -110,6 +110,11 @@ public enum EmfRecordType : uint
     /// </summary>
     EMR_SELECTOBJECT = 0x00000025,
 
+    /// <summary>
+    /// Deletes a graphics object, clearing its index in the EMF object table
+    /// </summary>
+    EMR_DELETEOBJECT = 0x00000028,
+
     /// <summary>
     /// Defines a line segment of an arc
     /// </summary>
diff --git a/src/SharpEmf/Records/EnhancedMetafileRecord.cs b/src/SharpEmf/Records/EnhancedMetafileRecord.cs
index 3a61af8..07e0c2b 100644
--- a/src/SharpEmf/Records/EnhancedMetafileRecord.cs
+++ b/src/SharpEmf/Records/EnhancedMetafileRecord.cs
@@ -55,6 +55,7 @@ public static EnhancedMetafileRecord Parse(Stream stream)
             EmfRecordType.EMR_EXCLUDECLIPRECT => EmrExcludeClipRect.Parse,
             EmfRecordType.EMR_INTERSECTCLIPRECT => EmrIntersectClipRect.Parse,
             EmfRecordType.EMR_SELECTOBJECT => EmrSelectObject.Parse,
+            EmfRecordType.EMR_DELETEOBJECT => EmrDeleteObject.Parse,
             EmfRecordType.EMR_ANGLEARC => EmrAngleArc.Parse,
             EmfRecordType.EMR_ELLIPSE => EmrEllipse.Parse,
             EmfRecordType.EMR_RECTANGLE => EmrRectangle.Parse,
diff --git a/src/SharpEmf/Records/ObjectManipulation/EmrDeleteObject.cs b/src/SharpEmf/Records/ObjectManipulation/EmrDeleteObject.cs
new file mode 100644
index 0000000..342edf0
--- /dev/null
+++ b/src/SharpEmf/Records/ObjectManipulation/EmrDeleteObject.cs
@@ -0,0 +1,43 @@
+using JetBrains.Annotations;
+using SharpEmf.Enums;
+using SharpEmf.Exceptions;
+using SharpEmf.Extensions;
+using SharpEmf.Interfaces;
+
+namespace SharpEmf.Records.ObjectManipulation;
+
+/// <inheritdoc cref="EmfRecordType.EMR_DELETEOBJECT"/>
+[PublicAPI]
+public record EmrDeleteObject : EnhancedMetafileRecord, IEmfParsable<EmrDeleteObject>
+{
+    /// <summary>
+    /// Specifies the index of a graphics object in the EMF object table
+    /// </summary>
+    /// <remarks>
+    /// This value MUST NOT be 0, which is a reserved index that refers to the EMF metafile itself;
+    /// and it MUST NOT be the index of a <see cref="StockObject"/>, which cannot be deleted
+    /// </remarks>
+    public uint IhObject { get; }
+
+    private EmrDeleteObject(EmfRecordType Type, uint Size, uint ihObject) : base(Type, Size)
+    {
+        IhObject = ihObject;
+    }
+
+    public static EmrDeleteObject Parse(Stream stream, EmfRecordType recordType, uint size)
+    {
+        var ihObject = stream.ReadUInt32();
+
+        if (ihObject == 0)
+        {
+            throw new EmfParseException("Object index MUST NOT be zero");
+        }
+
+        if (Enum.IsDefined(typeof(StockObject), ihObject))
+        {
+            throw new EmfParseException("Object index MUST NOT be a stock object");
+        }
+
+        return new EmrDeleteObject(recordType, size, ihObject);
+    }
+}
\ No newline at end of file