TagTool.Cache.TagCache.SetTagData C# (CSharp) Method

        public void SetTagData(Stream stream, TagInstance tag, TagData data)
        {
            if (tag == null)
                throw new ArgumentNullException(nameof(tag));
            if (data == null)
                throw new ArgumentNullException(nameof(data));
            if (data.Group == TagGroup.Null)
                throw new ArgumentException("Cannot assign a tag to a null tag group");
            if (data.Data == null)
                throw new ArgumentException("The tag data buffer is null");

            // Ensure the data fits
            var headerSize = TagInstance.CalculateHeaderSize(data);
            var alignedHeaderSize = (uint)((headerSize + 0xF) & ~0xF);
            if (tag.HeaderOffset < 0)
                tag.HeaderOffset = GetNewTagOffset(tag.Index);
            var alignedLength = (data.Data.Length + 0xF) & ~0xF;
            ResizeBlock(stream, tag, tag.HeaderOffset, tag.TotalSize, alignedHeaderSize + alignedLength);
            tag.TotalSize = alignedHeaderSize + alignedLength;
            tag.Update(data, alignedHeaderSize);

            // Write in the new header and data
            stream.Position = tag.HeaderOffset;
            var writer = new BinaryWriter(stream);
            tag.WriteHeader(writer);
            StreamUtil.Fill(stream, 0, (int)(alignedHeaderSize - headerSize));
            stream.Write(data.Data, 0, data.Data.Length);
            StreamUtil.Fill(stream, 0, alignedLength - data.Data.Length);

            // Correct pointers
            foreach (var fixup in data.PointerFixups)
            {
                writer.BaseStream.Position = tag.HeaderOffset + alignedHeaderSize + fixup.WriteOffset;
                writer.Write(tag.OffsetToPointer(alignedHeaderSize + fixup.TargetOffset));
            }
            UpdateTagOffsets(writer);
        }