more api

LuckPerms.Torch.Utils/Utils/Extensions/StreamExtensions.cs

@@ -0,0 +1,92 @@
+using java.io;
+using JavaIOException = java.io.IOException;
+using SystemIOException = System.IO.IOException;
+
+namespace LuckPerms.Torch.Utils.Extensions;
+
+public static class StreamExtensions
+{
+    public static InputStream GetInputStream(this Stream stream)
+    {
+        if (!stream.CanRead)
+            throw new ArgumentException("Stream should be readable", nameof(stream));
+
+        return new WrapperInputStream(stream);
+    }
+
+    private sealed class WrapperInputStream(Stream stream) : InputStream
+    {
+        public override int read()
+        {
+            try
+            {
+                return stream.ReadByte();
+            }
+            catch (SystemIOException e)
+            {
+                throw new JavaIOException(e.Message, e);
+            }
+        }
+
+        public override int read(byte[] b, int off, int len)
+        {
+            try
+            {
+                return stream.Read(b, off, len);
+            }
+            catch (SystemIOException e)
+            {
+                throw new JavaIOException(e.Message, e);
+            }
+        }
+
+        public override long skip(long n)
+        {
+            if (!stream.CanSeek) return base.skip(n);
+            
+            try
+            {
+                return stream.Seek(n, SeekOrigin.Current);
+            }
+            catch (SystemIOException e)
+            {
+                throw new JavaIOException(e.Message, e);
+            }
+        }
+
+        public override int available()
+        {
+            try
+            {
+                return (int)(stream.Length - stream.Position);
+            }
+            catch (SystemIOException e)
+            {
+                throw new JavaIOException(e.Message, e);
+            }
+        }
+
+        public override void reset()
+        {
+            if (!stream.CanSeek)
+            {
+                base.reset();
+                return;
+            }
+            
+            try
+            {
+                stream.Seek(0, SeekOrigin.Begin);
+            }
+            catch (SystemIOException e)
+            {
+                throw new JavaIOException(e.Message, e);
+            }
+        }
+
+        public override void close()
+        {
+            stream.Dispose();
+        }
+    }
+}