Fix error reading metadata

Dotnet/AppApi/Common/ImageSaving.cs

@@ -199,8 +199,8 @@ namespace VRCX
             
             await print.SaveAsPngAsync(tempPath);
             
-            var oldPngFile = new PNGFile(path);
+            var oldPngFile = new PNGFile(path, false);
-            var newPngFile = new PNGFile(tempPath);
+            var newPngFile = new PNGFile(tempPath, true);
 
             // Copy all iTXt chunks to new file
             var textChunks = oldPngFile.GetChunksOfType(PNGChunkTypeFilter.iTXt);

Dotnet/AppApi/Common/Screenshot.cs

@@ -35,7 +35,7 @@ public partial class AppApi
             }
         }
 
-        using var png = new PNGFile(path);
+        using var png = new PNGFile(path, false);
         metadata.Add("fileResolution", PNGHelper.ReadResolution(png));
 
         var creationDate = File.GetCreationTime(path);

Dotnet/ScreenshotMetadata/PNGFile.cs

@@ -23,9 +23,10 @@ public class PNGFile : IDisposable
     /// Opens the PNG file for reading and writing.
     /// </summary>
     /// <param name="filePath">The path to the PNG file to open for reading and writing.</param>
-    public PNGFile(string filePath)
+    /// <param name="writeAccess">Open file with write permissions.</param>
+    public PNGFile(string filePath, bool writeAccess)
     {
-        fileStream = new FileStream(filePath, FileMode.Open, FileAccess.ReadWrite, FileShare.ReadWrite, 4096);
+        fileStream = new FileStream(filePath, FileMode.Open, writeAccess ? FileAccess.ReadWrite : FileAccess.Read, FileShare.ReadWrite, 4096);
     }
     
     public PNGFile(string filePath, int bufferSize)

Dotnet/ScreenshotMetadata/ScreenshotHelper.cs

@@ -196,7 +196,7 @@ namespace VRCX
         /// </remarks>
         public static List<string> ReadTextMetadata(string path)
         {
-            using var pngFile = new PNGFile(path);
+            using var pngFile = new PNGFile(path, false);
             var result = new List<string>();
             var metadata = PNGHelper.ReadTextChunk("Description", pngFile);
             var vrchatMetadata = PNGHelper.ReadTextChunk("XML:com.adobe.xmp", pngFile);
@@ -231,7 +231,7 @@ namespace VRCX
         
         public static bool WriteVRCXMetadata(string text, string path)
         {
-            using var pngFile = new PNGFile(path);
+            using var pngFile = new PNGFile(path, true);
             var chunk = PNGHelper.GenerateTextChunk("Description", text);
             
             return pngFile.WriteChunk(chunk);;