Implement WixOutput with support for multiple streams of data

21 files changed, 399 insertions, 846 deletions

diff --git a/src/WixToolset.Data/ErrorMessages.cs b/src/WixToolset.Data/ErrorMessages.cs
index 33cccdd2..3fa23a74 100644
--- a/src/WixToolset.Data/ErrorMessages.cs
+++ b/src/WixToolset.Data/ErrorMessages.cs
@@ -198,9 +198,9 @@ namespace WixToolset.Data
             return Message(sourceLineNumbers, Ids.ConditionExpected, "The {0} element's inner text cannot be an empty string or completely whitespace.  If you don't want a condition, then simply remove the entire {0} element.", elementName);
         }
 
-        public static Message CorruptFileFormat(string path, FileFormat format)
+        public static Message CorruptFileFormat(string path, string format)
         {
-            return Message(null, Ids.CorruptFileFormat, "Attempted to load corrupt file from path: {0}. The file with format {1} contained unexpected content. Ensure the correct path was provided and that the file has not been incorrectly modified.", path, format.ToString().ToLowerInvariant());
+            return Message(null, Ids.CorruptFileFormat, "Attempted to load corrupt file from path: {0}. The file with format {1} contained unexpected content. Ensure the correct path was provided and that the file has not been incorrectly modified.", path, format.ToLowerInvariant());
         }
 
         public static Message CreateCabAddFileFailed()
@@ -2049,9 +2049,9 @@ namespace WixToolset.Data
             return Message(null, Ids.UnexpectedFileExtension, "The file '{0}' has an unexpected extension. Expected one of the following: '{1}'.", fileName, expectedExtensions);
         }
 
-        public static Message UnexpectedFileFormat(string path, FileFormat expectedFormat, FileFormat actualFormat)
+        public static Message UnexpectedFileFormat(string path, string expectedFormat, string actualFormat)
         {
-            return Message(null, Ids.UnexpectedFileFormat, "Unexpected file format loaded from path: {0}. The file was expected to be a {1} but was actually: {2}. Ensure the correct path was provided.", path, expectedFormat.ToString().ToLowerInvariant(), actualFormat.ToString().ToLowerInvariant());
+            return Message(null, Ids.UnexpectedFileFormat, "Unexpected file format loaded from path: {0}. The file was expected to be a {1} but was actually: {2}. Ensure the correct path was provided.", path, expectedFormat.ToLowerInvariant(), actualFormat.ToLowerInvariant());
         }
 
         public static Message UnexpectedGroupChild(string parentType, string parentId, string childType, string childId)
diff --git a/src/WixToolset.Data/FileFormat.cs b/src/WixToolset.Data/FileFormat.cs
deleted file mode 100644
index 75eab3de..00000000
--- a/src/WixToolset.Data/FileFormat.cs
+++ /dev/null
@@ -1,19 +0,0 @@
-// Copyright (c) .NET Foundation and contributors. All rights reserved. Licensed under the Microsoft Reciprocal License. See LICENSE.TXT file in the project root for full license information.
-
-namespace WixToolset.Data
-{
-    public enum FileFormat
-    {
-        Unknown,
-
-        Wixobj,
-
-        Wixlib,
-
-        Wixout,
-
-        Wixpdb,
-
-        WixIR,
-    }
-}
diff --git a/src/WixToolset.Data/FileStructure.cs b/src/WixToolset.Data/FileStructure.cs
deleted file mode 100644
index 2667df1e..00000000
--- a/src/WixToolset.Data/FileStructure.cs
+++ /dev/null
@@ -1,316 +0,0 @@
-// Copyright (c) .NET Foundation and contributors. All rights reserved. Licensed under the Microsoft Reciprocal License. See LICENSE.TXT file in the project root for full license information.
-
-namespace WixToolset.Data
-{
-    using System;
-    using System.Collections.Generic;
-    using System.Diagnostics;
-    using System.IO;
-    using System.Linq;
-    using System.Text;
-
-    /// <summary>
-    /// Class that understands the standard file structures in the WiX toolset.
-    /// </summary>
-    public class FileStructure : IDisposable
-    {
-        private long dataStreamOffset;
-        private long[] embeddedFileSizes;
-        private Stream stream;
-        private bool disposed;
-
-        private static readonly Dictionary<string, FileFormat> SupportedFileFormats = new Dictionary<string, FileFormat>()
-        {
-            { "wir", FileFormat.WixIR },
-            { "wixirf", FileFormat.WixIR },
-            { "wixipl", FileFormat.WixIR },
-            { "wixobj", FileFormat.Wixobj },
-            { "wixlib", FileFormat.Wixlib },
-            { "wixout", FileFormat.Wixout },
-            { "wixpdb", FileFormat.Wixpdb },
-            { "wixmst", FileFormat.Wixout },
-            { "wixmsp", FileFormat.Wixout },
-        };
-
-        /// <summary>
-        /// Use Create or Read to create a FileStructure.
-        /// </summary>
-        private FileStructure() { }
-
-        /// <summary>
-        /// Count of embedded files in the file structure.
-        /// </summary>
-        public int EmbeddedFileCount => this.embeddedFileSizes.Length;
-
-        /// <summary>
-        /// File format of the file structure.
-        /// </summary>
-        public FileFormat FileFormat { get; private set; }
-
-        /// <summary>
-        /// Creates a new file structure.
-        /// </summary>
-        /// <param name="stream">Stream to write the file structure to.</param>
-        /// <param name="fileFormat">File format for the file structure.</param>
-        /// <param name="embedFilePaths">Paths to files to embedd in the file structure.</param>
-        /// <returns>Newly created file structure.</returns>
-        public static FileStructure Create(Stream stream, FileFormat fileFormat, IEnumerable<string> embedFilePaths)
-        {
-            var fs = new FileStructure();
-
-            using (var writer = new BinaryWriter(stream, Encoding.UTF8, true))
-            {
-                fs.WriteType(writer, fileFormat);
-
-                fs.WriteEmbeddedFiles(writer, embedFilePaths?.ToArray() ?? Array.Empty<string>());
-
-                // Remember the data stream offset, which is right after the embedded files have been written.
-                fs.dataStreamOffset = stream.Position;
-            }
-
-            fs.stream = stream;
-
-            return fs;
-        }
-
-        /// <summary>
-        /// Reads a file structure from an open stream.
-        /// </summary>
-        /// <param name="stream">Stream to read from.</param>
-        /// <returns>File structure populated from the stream.</returns>
-        public static FileStructure Read(Stream stream)
-        {
-            var fs = new FileStructure();
-
-            using (var reader = new BinaryReader(stream, Encoding.UTF8, true))
-            {
-                fs.FileFormat = FileStructure.ReadFileFormat(reader);
-
-                if (fs.FileFormat != FileFormat.Unknown)
-                {
-                    fs.embeddedFileSizes = FileStructure.ReadEmbeddedFileSizes(reader);
-
-                    // Remember the data stream offset, which is right after the embedded files have been written.
-                    fs.dataStreamOffset = stream.Position;
-                    foreach (long size in fs.embeddedFileSizes)
-                    {
-                        fs.dataStreamOffset += size;
-                    }
-                }
-            }
-
-            fs.stream = stream;
-
-            return fs;
-        }
-
-        /// <summary>
-        /// Guess at the file format based on the file extension.
-        /// </summary>
-        /// <param name="extension">File extension to guess the file format for.</param>
-        /// <returns>Best guess at file format.</returns>
-        public static FileFormat GuessFileFormatFromExtension(string extension)
-        {
-            return FileStructure.SupportedFileFormats.TryGetValue(extension.TrimStart('.').ToLowerInvariant(), out var format) ? format : FileFormat.Unknown;
-        }
-
-        /// <summary>
-        /// Probes a stream to determine the file format.
-        /// </summary>
-        /// <param name="stream">Stream to test.</param>
-        /// <returns>The file format.</returns>
-        public static FileFormat TestFileFormat(Stream stream)
-        {
-            FileFormat format = FileFormat.Unknown;
-
-            long position = stream.Position;
-
-            try
-            {
-                using (var reader = new BinaryReader(stream, Encoding.UTF8, true))
-                {
-                    format = FileStructure.ReadFileFormat(reader);
-                }
-            }
-            finally
-            {
-                stream.Seek(position, SeekOrigin.Begin);
-            }
-
-            return format;
-        }
-
-        /// <summary>
-        /// Extracts an embedded file.
-        /// </summary>
-        /// <param name="embeddedIndex">Index to the file to extract.</param>
-        /// <param name="outputPath">Path to write the extracted file to.</param>
-        public void ExtractEmbeddedFile(int embeddedIndex, string outputPath)
-        {
-            if (this.EmbeddedFileCount <= embeddedIndex)
-            {
-                throw new ArgumentOutOfRangeException("embeddedIndex");
-            }
-
-            long header = 6 + 4 + (this.embeddedFileSizes.Length * 8); // skip the type + the count of embedded files + all the sizes of embedded files.
-            long position = this.embeddedFileSizes.Take(embeddedIndex).Sum(); // skip to the embedded file we want.
-            long size = this.embeddedFileSizes[embeddedIndex];
-
-            this.stream.Seek(header + position, SeekOrigin.Begin);
-
-            Directory.CreateDirectory(Path.GetDirectoryName(outputPath));
-
-            using (FileStream output = File.OpenWrite(outputPath))
-            {
-                int read;
-                int total = 0;
-                byte[] buffer = new byte[64 * 1024];
-                while (0 < (read = this.stream.Read(buffer, 0, (int)Math.Min(buffer.Length, size - total))))
-                {
-                    output.Write(buffer, 0, read);
-                    total += read;
-                }
-            }
-        }
-
-        /// <summary>
-        /// Gets a non-closing stream to the data of the file.
-        /// </summary>
-        /// <returns>Stream to the data of the file.</returns>
-        public Stream GetDataStream()
-        {
-            this.stream.Seek(this.dataStreamOffset, SeekOrigin.Begin);
-            return new NonClosingStreamWrapper(this.stream);
-        }
-
-        /// <summary>
-        /// Gets the data of the file as a string.
-        /// </summary>
-        /// <returns>String contents data of the file.</returns>
-        public string GetData()
-        {
-            var bytes = new byte[this.stream.Length - this.dataStreamOffset];
-
-            this.stream.Seek(this.dataStreamOffset, SeekOrigin.Begin);
-            this.stream.Read(bytes, 0, bytes.Length);
-
-            return Encoding.UTF8.GetString(bytes);
-        }
-
-        /// <summary>
-        /// Disposes of the internal state of the file structure.
-        /// </summary>
-        public void Dispose()
-        {
-            Dispose(true);
-            GC.SuppressFinalize(this);
-        }
-
-        /// <summary>
-        /// Disposes of the internsl state of the file structure.
-        /// </summary>
-        /// <param name="disposing">True if disposing.</param>
-        protected virtual void Dispose(bool disposing)
-        {
-            if (!this.disposed)
-            {
-                if (disposing)
-                {
-                    if (null != this.stream)
-                    {
-                        // We do not own the stream, so we don't close it. We're just resetting our internal state.
-                        this.embeddedFileSizes = null;
-                        this.dataStreamOffset = 0;
-                        this.stream = null;
-                    }
-                }
-            }
-
-            this.disposed = true;
-        }
-
-        private static FileFormat ReadFileFormat(BinaryReader reader)
-        {
-            FileFormat format = FileFormat.Unknown;
-
-            string type = new string(reader.ReadChars(3));
-            if (FileStructure.SupportedFileFormats.TryGetValue(type, out format))
-            {
-                return format;
-            }
-
-            type += new string(reader.ReadChars(3));
-            FileStructure.SupportedFileFormats.TryGetValue(type, out format);
-
-            return format;
-        }
-
-        private static long[] ReadEmbeddedFileSizes(BinaryReader reader)
-        {
-            uint count = reader.ReadUInt32();
-
-            long[] embeddedFileSizes = new long[count];
-
-            for (int i = 0; i < embeddedFileSizes.Length; ++i)
-            {
-                embeddedFileSizes[i] = (long)reader.ReadUInt64();
-            }
-
-            return embeddedFileSizes;
-        }
-
-        private BinaryWriter WriteType(BinaryWriter writer, FileFormat fileFormat)
-        {
-            string type = null;
-            foreach (var supported in FileStructure.SupportedFileFormats)
-            {
-                if (supported.Value.Equals(fileFormat))
-                {
-                    type = supported.Key;
-                    break;
-                }
-            }
-
-            if (String.IsNullOrEmpty(type))
-            {
-                throw new ArgumentException("Unknown file format type", "fileFormat");
-            }
-
-            this.FileFormat = fileFormat;
-
-            Debug.Assert(3 == type.ToCharArray().Length || 6 == type.ToCharArray().Length);
-            writer.Write(type.ToCharArray());
-            return writer;
-        }
-
-        private BinaryWriter WriteEmbeddedFiles(BinaryWriter writer, string[] embedFilePaths)
-        {
-            // First write the count of embedded files as a Uint32;
-            writer.Write((uint)embedFilePaths.Length);
-
-            this.embeddedFileSizes = new long[embedFilePaths.Length];
-
-            // Next write out the size of each file as a Uint64 in order.
-            FileInfo[] files = new FileInfo[embedFilePaths.Length];
-            for (int i = 0; i < embedFilePaths.Length; ++i)
-            {
-                files[i] = new FileInfo(embedFilePaths[i]);
-
-                this.embeddedFileSizes[i] = files[i].Length;
-                writer.Write((ulong)this.embeddedFileSizes[i]);
-            }
-
-            // Next write out the content of each file *after* the sizes of
-            // *all* of the files were written.
-            foreach (FileInfo file in files)
-            {
-                using (FileStream stream = file.OpenRead())
-                {
-                    stream.CopyTo(writer.BaseStream);
-                }
-            }
-
-            return writer;
-        }
-    }
-}
diff --git a/src/WixToolset.Data/Intermediate.cs b/src/WixToolset.Data/Intermediate.cs
index 7693b815..1db21d85 100644
--- a/src/WixToolset.Data/Intermediate.cs
+++ b/src/WixToolset.Data/Intermediate.cs
@@ -14,8 +14,8 @@ namespace WixToolset.Data
     /// </summary>
     public sealed class Intermediate
     {
-        public const string XmlNamespaceUri = "http://wixtoolset.org/schemas/v4/wixobj";
         private static readonly Version CurrentVersion = new Version("4.0.0.0");
+        private const string WixOutputStreamName = "wix-ir.json";
 
         private readonly Dictionary<string, Localization> localizationsByCulture;
 
@@ -25,15 +25,13 @@ namespace WixToolset.Data
         public Intermediate()
         {
             this.Id = Convert.ToBase64String(Guid.NewGuid().ToByteArray()).TrimEnd('=').Replace('+', '.').Replace('/', '_');
-            this.EmbedFilePaths = new List<string>();
             this.localizationsByCulture = new Dictionary<string, Localization>(StringComparer.OrdinalIgnoreCase);
             this.Sections = new List<IntermediateSection>();
         }
 
-        public Intermediate(string id, IEnumerable<IntermediateSection> sections, IDictionary<string, Localization> localizationsByCulture, IEnumerable<string> embedFilePaths)
+        public Intermediate(string id, IEnumerable<IntermediateSection> sections, IDictionary<string, Localization> localizationsByCulture)
         {
             this.Id = id;
-            this.EmbedFilePaths = (embedFilePaths != null) ? new List<string>(embedFilePaths) : new List<string>();
             this.localizationsByCulture = (localizationsByCulture != null) ? new Dictionary<string, Localization>(localizationsByCulture, StringComparer.OrdinalIgnoreCase) : new Dictionary<string, Localization>(StringComparer.OrdinalIgnoreCase);
             this.Sections = (sections != null) ? new List<IntermediateSection>(sections) : new List<IntermediateSection>();
         }
@@ -44,11 +42,6 @@ namespace WixToolset.Data
         public string Id { get; }
 
         /// <summary>
-        /// Get the embed file paths in this intermediate.
-        /// </summary>
-        public IList<string> EmbedFilePaths { get; }
-
-        /// <summary>
         /// Get the localizations contained in this intermediate.
         /// </summary>
         public IEnumerable<Localization> Localizations => this.localizationsByCulture.Values;
@@ -66,12 +59,8 @@ namespace WixToolset.Data
         /// <returns>Returns the loaded intermediate.</returns>
         public static Intermediate Load(string path, bool suppressVersionCheck = false)
         {
-            using (var stream = File.OpenRead(path))
-            {
-                var uri = new Uri(Path.GetFullPath(path));
-                var creator = new SimpleTupleDefinitionCreator();
-                return Intermediate.LoadIntermediate(stream, uri, creator, suppressVersionCheck);
-            }
+            var creator = new SimpleTupleDefinitionCreator();
+            return Intermediate.Load(path, creator, suppressVersionCheck);
         }
 
         /// <summary>
@@ -97,13 +86,9 @@ namespace WixToolset.Data
         /// <returns>Returns the loaded intermediate.</returns>
         public static Intermediate Load(Assembly assembly, string resourceName, ITupleDefinitionCreator creator, bool suppressVersionCheck = false)
         {
-            using (var resourceStream = assembly.GetManifestResourceStream(resourceName))
+            using (var wixout = WixOutput.Read(assembly, resourceName))
             {
-                var uriBuilder = new UriBuilder(assembly.CodeBase);
-                uriBuilder.Scheme = "embeddedresource";
-                uriBuilder.Fragment = resourceName;
-
-                return Intermediate.LoadIntermediate(resourceStream, uriBuilder.Uri, creator, suppressVersionCheck);
+                return Intermediate.LoadIntermediate(wixout, creator, suppressVersionCheck);
             }
         }
 
@@ -116,11 +101,9 @@ namespace WixToolset.Data
         /// <returns>Returns the loaded intermediate.</returns>
         public static Intermediate Load(string path, ITupleDefinitionCreator creator, bool suppressVersionCheck = false)
         {
-            using (var stream = File.OpenRead(path))
+            using (var wixout = WixOutput.Read(path))
             {
-                var uri = new Uri(Path.GetFullPath(path));
-
-                return Intermediate.LoadIntermediate(stream, uri, creator, suppressVersionCheck);
+                return Intermediate.LoadIntermediate(wixout, creator, suppressVersionCheck);
             }
         }
 
@@ -133,7 +116,6 @@ namespace WixToolset.Data
         public static IEnumerable<Intermediate> Load(IEnumerable<string> intermediateFiles)
         {
             var creator = new SimpleTupleDefinitionCreator();
-
             return Intermediate.Load(intermediateFiles, creator);
         }
 
@@ -151,15 +133,14 @@ namespace WixToolset.Data
 
             foreach (var path in intermediateFiles)
             {
-                using (var stream = File.OpenRead(path))
+                using (var wixout = WixOutput.Read(path))
                 {
-                    var uri = new Uri(Path.GetFullPath(path));
-
-                    var json = Intermediate.LoadJson(stream, uri, suppressVersionCheck);
+                    var data = wixout.GetData(WixOutputStreamName);
+                    var json = Intermediate.LoadJson(data, wixout.Uri, suppressVersionCheck);
 
                     Intermediate.LoadDefinitions(json, creator);
 
-                    jsons.Enqueue(new JsonWithPath { Json = json, Path = uri });
+                    jsons.Enqueue(new JsonWithPath { Json = json, Path = wixout.Uri });
                 }
             }
 
@@ -183,55 +164,21 @@ namespace WixToolset.Data
         {
             Directory.CreateDirectory(Path.GetDirectoryName(Path.GetFullPath(path)));
 
-            using (var stream = File.Create(path))
-            using (var fs = FileStructure.Create(stream, FileFormat.WixIR, this.EmbedFilePaths))
-            using (var writer = new StreamWriter(fs.GetDataStream()))
+            using (var wixout = WixOutput.Create(path))
             {
-                var jsonObject = new JsonObject
-                {
-                    { "id", this.Id },
-                    { "version", Intermediate.CurrentVersion.ToString() }
-                };
-
-                var sectionsJson = new JsonArray(this.Sections.Count);
-                foreach (var section in this.Sections)
-                {
-                    var sectionJson = section.Serialize();
-                    sectionsJson.Add(sectionJson);
-                }
-
-                jsonObject.Add("sections", sectionsJson);
-
-                var customDefinitions = this.GetCustomDefinitionsInSections();
-
-                if (customDefinitions.Count > 0)
-                {
-                    var customDefinitionsJson = new JsonArray(customDefinitions.Count);
-
-                    foreach (var kvp in customDefinitions.OrderBy(d => d.Key))
-                    {
-                        var customDefinitionJson = kvp.Value.Serialize();
-                        customDefinitionsJson.Add(customDefinitionJson);
-                    }
-
-                    jsonObject.Add("definitions", customDefinitionsJson);
-                }
-
-                if (this.Localizations.Any())
-                {
-                    var localizationsJson = new JsonArray();
-                    foreach (var localization in this.Localizations)
-                    {
-                        var localizationJson = localization.Serialize();
-                        localizationsJson.Add(localizationJson);
-                    }
+                this.Save(wixout);
+            }
+        }
 
-                    jsonObject.Add("localizations", localizationsJson);
-                }
+        /// <summary>
+        /// Saves an intermediate to a path on disk.
+        /// </summary>
+        /// <param name="path">Path to save intermediate file to disk.</param>
+        public void Save(WixOutput wixout)
+        {
+            this.SaveEmbedFiles(wixout);
 
-                var json = SimpleJson.SerializeObject(jsonObject);
-                writer.Write(json);
-            }
+            this.SaveIR(wixout);
         }
 
         /// <summary>
@@ -242,13 +189,14 @@ namespace WixToolset.Data
         /// <param name="creator">ITupleDefinitionCreator to use when reconstituting the intermediate.</param>
         /// <param name="suppressVersionCheck">Suppress checking for wix.dll version mismatches.</param>
         /// <returns>Returns the loaded intermediate.</returns>
-        private static Intermediate LoadIntermediate(Stream stream, Uri baseUri, ITupleDefinitionCreator creator, bool suppressVersionCheck = false)
+        private static Intermediate LoadIntermediate(WixOutput wixout, ITupleDefinitionCreator creator, bool suppressVersionCheck = false)
         {
-            var json = Intermediate.LoadJson(stream, baseUri, suppressVersionCheck);
+            var data = wixout.GetData(WixOutputStreamName);
+            var json = Intermediate.LoadJson(data, wixout.Uri, suppressVersionCheck);
 
             Intermediate.LoadDefinitions(json, creator);
 
-            return Intermediate.FinalizeLoad(json, baseUri, creator);
+            return Intermediate.FinalizeLoad(json, wixout.Uri, creator);
         }
 
         /// <summary>
@@ -258,19 +206,9 @@ namespace WixToolset.Data
         /// <param name="baseUri">Path name of intermediate file.</param>
         /// <param name="suppressVersionCheck">Suppress checking for wix.dll version mismatches.</param>
         /// <returns>Returns the loaded json.</returns>
-        private static JsonObject LoadJson(Stream stream, Uri baseUri, bool suppressVersionCheck)
+        private static JsonObject LoadJson(string json, Uri baseUri, bool suppressVersionCheck)
         {
-            JsonObject jsonObject;
-            using (var fs = FileStructure.Read(stream))
-            {
-                if (FileFormat.WixIR != fs.FileFormat)
-                {
-                    throw new WixUnexpectedFileFormatException(baseUri.LocalPath, FileFormat.WixIR, fs.FileFormat);
-                }
-
-                var json = fs.GetData();
-                jsonObject = SimpleJson.DeserializeObject(json) as JsonObject;
-            }
+            var jsonObject = SimpleJson.DeserializeObject(json) as JsonObject;
 
             if (!suppressVersionCheck)
             {
@@ -333,153 +271,118 @@ namespace WixToolset.Data
                 localizations.Add(localization.Culture, localization);
             }
 
-            return new Intermediate(id, sections, localizations, null);
+            return new Intermediate(id, sections, localizations);
         }
 
-#if false
-        /// <summary>
-        /// Loads an intermediate from a path on disk.
-        /// </summary>
-        /// <param name="path">Path to intermediate file saved on disk.</param>
-        /// <param name="tableDefinitions">Collection containing TableDefinitions to use when reconstituting the intermediate.</param>
-        /// <param name="suppressVersionCheck">Suppress checking for wix.dll version mismatches.</param>
-        /// <returns>Returns the loaded intermediate.</returns>
-        public static Intermediate Load(string path, TableDefinitionCollection tableDefinitions, bool suppressVersionCheck)
+        private void SaveEmbedFiles(WixOutput wixout)
         {
-            using (FileStream stream = File.OpenRead(path))
-            using (FileStructure fs = FileStructure.Read(stream))
+            var embeddedFields = this.Sections.SelectMany(s => s.Tuples)
+                .SelectMany(t => t.Fields)
+                .Where(f => f?.Type == IntermediateFieldType.Path)
+                .Select(f => f.AsPath())
+                .Where(f => f.Embed)
+                .ToList();
+
+            var savedEmbedFields = new Dictionary<string, IntermediateFieldPathValue>(StringComparer.OrdinalIgnoreCase);
+            var uniqueEntryNames = new HashSet<string>(StringComparer.OrdinalIgnoreCase);
+
+            foreach (var embeddedField in embeddedFields)
             {
-                if (FileFormat.Wixobj != fs.FileFormat)
+                var key = String.Concat(embeddedField.BaseUri?.AbsoluteUri, "?", embeddedField.Path);
+
+                if (savedEmbedFields.TryGetValue(key, out var existing))
                 {
-                    throw new WixUnexpectedFileFormatException(path, FileFormat.Wixobj, fs.FileFormat);
+                    embeddedField.Path = existing.Path;
                 }
-
-                Uri uri = new Uri(Path.GetFullPath(path));
-                using (XmlReader reader = XmlReader.Create(fs.GetDataStream(), null, uri.AbsoluteUri))
+                else
                 {
-                    try
+                    var entryName = CalculateUniqueEntryName(uniqueEntryNames, embeddedField.Path);
+
+                    if (embeddedField.BaseUri == null)
                     {
-                        reader.MoveToContent();
-                        return Intermediate.Read(reader, tableDefinitions, suppressVersionCheck);
+                        wixout.ImportDataStream(entryName, embeddedField.Path);
                     }
-                    catch (XmlException xe)
+                    else // open the container specified in baseUri and copy the correct stream out of it.
                     {
-                        throw new WixCorruptFileException(path, fs.FileFormat, xe);
+                        using (var otherWixout = WixOutput.Read(embeddedField.BaseUri))
+                        using (var stream = otherWixout.GetDataStream(embeddedField.Path))
+                        using (var target = wixout.CreateDataStream(entryName))
+                        {
+                            stream.CopyTo(target);
+                        }
                     }
-                }
-            }
-        }
 
-        /// <summary>
-        /// Saves an intermediate to a path on disk.
-        /// </summary>
-        /// <param name="path">Path to save intermediate file to disk.</param>
-        public void Save(string path)
-        {
-            Directory.CreateDirectory(Path.GetDirectoryName(Path.GetFullPath(path)));
+                    embeddedField.Path = entryName;
 
-            using (var stream = File.Create(path))
-            using (var fs = FileStructure.Create(stream, FileFormat.Wixobj, null))
-            using (var writer = XmlWriter.Create(fs.GetDataStream()))
-            {
-                writer.WriteStartDocument();
-                this.Write(writer);
-                writer.WriteEndDocument();
+                    savedEmbedFields.Add(key, embeddedField);
+                }
             }
         }
 
-        /// <summary>
-        /// Parse an intermediate from an XML format.
-        /// </summary>
-        /// <param name="reader">XmlReader where the intermediate is persisted.</param>
-        /// <param name="tableDefinitions">TableDefinitions to use in the intermediate.</param>
-        /// <param name="suppressVersionCheck">Suppress checking for wix.dll version mismatch.</param>
-        /// <returns>The parsed Intermediate.</returns>
-        private static Intermediate Read(XmlReader reader, TableDefinitionCollection tableDefinitions, bool suppressVersionCheck)
+        private void SaveIR(WixOutput wixout)
         {
-            if ("wixObject" != reader.LocalName)
+            using (var writer = new StreamWriter(wixout.CreateDataStream(WixOutputStreamName)))
             {
-                throw new XmlException();
-            }
-
-            bool empty = reader.IsEmptyElement;
-            Version objVersion = null;
-            string id = null;
+                var jsonObject = new JsonObject
+                {
+                    { "id", this.Id },
+                    { "version", Intermediate.CurrentVersion.ToString() }
+                };
 
-            while (reader.MoveToNextAttribute())
-            {
-                switch (reader.LocalName)
+                var sectionsJson = new JsonArray(this.Sections.Count);
+                foreach (var section in this.Sections)
                 {
-                    case "version":
-                        objVersion = new Version(reader.Value);
-                        break;
-                    case "id":
-                        id = reader.Value;
-                        break;
+                    var sectionJson = section.Serialize();
+                    sectionsJson.Add(sectionJson);
                 }
-            }
-
-            if (!suppressVersionCheck && null != objVersion && !Intermediate.CurrentVersion.Equals(objVersion))
-            {
-                throw new WixException(WixDataErrors.VersionMismatch(SourceLineNumber.CreateFromUri(reader.BaseURI), "object", objVersion.ToString(), Intermediate.CurrentVersion.ToString()));
-            }
 
-            Intermediate intermediate = new Intermediate();
-            intermediate.id = id;
+                jsonObject.Add("sections", sectionsJson);
 
-            if (!empty)
-            {
-                bool done = false;
+                var customDefinitions = this.GetCustomDefinitionsInSections();
 
-                while (!done && reader.Read())
+                if (customDefinitions.Count > 0)
                 {
-                    switch (reader.NodeType)
+                    var customDefinitionsJson = new JsonArray(customDefinitions.Count);
+
+                    foreach (var kvp in customDefinitions.OrderBy(d => d.Key))
                     {
-                        case XmlNodeType.Element:
-                            switch (reader.LocalName)
-                            {
-                                case "section":
-                                    intermediate.AddSection(Section.Read(reader, tableDefinitions));
-                                    break;
-                                default:
-                                    throw new XmlException();
-                            }
-                            break;
-                        case XmlNodeType.EndElement:
-                            done = true;
-                            break;
+                        var customDefinitionJson = kvp.Value.Serialize();
+                        customDefinitionsJson.Add(customDefinitionJson);
                     }
+
+                    jsonObject.Add("definitions", customDefinitionsJson);
                 }
 
-                if (!done)
+                if (this.Localizations.Any())
                 {
-                    throw new XmlException();
+                    var localizationsJson = new JsonArray();
+                    foreach (var localization in this.Localizations)
+                    {
+                        var localizationJson = localization.Serialize();
+                        localizationsJson.Add(localizationJson);
+                    }
+
+                    jsonObject.Add("localizations", localizationsJson);
                 }
-            }
 
-            return intermediate;
+                var json = SimpleJson.SerializeObject(jsonObject);
+                writer.Write(json);
+            }
         }
 
-        /// <summary>
-        /// Persists an intermediate in an XML format.
-        /// </summary>
-        /// <param name="writer">XmlWriter where the Intermediate should persist itself as XML.</param>
-        private void Write(XmlWriter writer)
+        private static string CalculateUniqueEntryName(ISet<string> entryNames, string path)
         {
-            writer.WriteStartElement("wixObject", XmlNamespaceUri);
-
-            writer.WriteAttributeString("version", Intermediate.CurrentVersion.ToString());
-
-            writer.WriteAttributeString("id", this.id);
+            var filename = Path.GetFileName(path);
+            var entryName = "wix-ir/" + filename;
+            var i = 0;
 
-            foreach (Section section in this.Sections)
+            while (!entryNames.Add(entryName))
             {
-                section.Write(writer);
+                entryName = $"wix-ir/{filename}-{++i}";
             }
 
-            writer.WriteEndElement();
+            return entryName;
         }
-#endif
 
         private Dictionary<string, IntermediateTupleDefinition> GetCustomDefinitionsInSections()
         {
diff --git a/src/WixToolset.Data/IntermediateFieldContext.cs b/src/WixToolset.Data/IntermediateFieldContext.cs
index a29a63c4..785a959f 100644
--- a/src/WixToolset.Data/IntermediateFieldContext.cs
+++ b/src/WixToolset.Data/IntermediateFieldContext.cs
@@ -1,4 +1,4 @@
-// Copyright (c) .NET Foundation and contributors. All rights reserved. Licensed under the Microsoft Reciprocal License. See LICENSE.TXT file in the project root for full license information.
+// Copyright (c) .NET Foundation and contributors. All rights reserved. Licensed under the Microsoft Reciprocal License. See LICENSE.TXT file in the project root for full license information.
 
 namespace WixToolset.Data
 {
@@ -6,7 +6,7 @@ namespace WixToolset.Data
 
     public class IntermediateFieldContext : IDisposable
     {
-        private string previous;
+        private readonly string previous;
         private bool disposed;
 
         public IntermediateFieldContext(string context)
@@ -18,7 +18,7 @@ namespace WixToolset.Data
 
         public void Dispose()
         {
-            Dispose(true);
+            this.Dispose(true);
             GC.SuppressFinalize(this);
         }
 
diff --git a/src/WixToolset.Data/IntermediateFieldExtensions.cs b/src/WixToolset.Data/IntermediateFieldExtensions.cs
index e488866e..06189b9c 100644
--- a/src/WixToolset.Data/IntermediateFieldExtensions.cs
+++ b/src/WixToolset.Data/IntermediateFieldExtensions.cs
@@ -386,7 +386,7 @@ namespace WixToolset.Data
 
                 default:
                     throw new ArgumentOutOfRangeException(nameof(value), $"Unknown intermediate field type: {value.GetType()}");
-                };
+                }
             }
 
             return AssignFieldValue(field, data);
@@ -455,7 +455,7 @@ namespace WixToolset.Data
 
                 default:
                     throw new ArgumentOutOfRangeException(nameof(value), $"Unknown intermediate field type: {value.GetType()}");
-                };
+                }
             }
 
             return AssignFieldValue(field, data);
diff --git a/src/WixToolset.Data/IntermediateFieldPathValue.cs b/src/WixToolset.Data/IntermediateFieldPathValue.cs
index 7d4fcdfe..a8d2735a 100644
--- a/src/WixToolset.Data/IntermediateFieldPathValue.cs
+++ b/src/WixToolset.Data/IntermediateFieldPathValue.cs
@@ -1,4 +1,4 @@
-// Copyright (c) .NET Foundation and contributors. All rights reserved. Licensed under the Microsoft Reciprocal License. See LICENSE.TXT file in the project root for full license information.
+// Copyright (c) .NET Foundation and contributors. All rights reserved. Licensed under the Microsoft Reciprocal License. See LICENSE.TXT file in the project root for full license information.
 
 namespace WixToolset.Data
 {
@@ -7,10 +7,9 @@ namespace WixToolset.Data
     public class IntermediateFieldPathValue
     {
         /// <summary>
-        /// Gets or sets the index of the embedded file in a library.
+        /// Indicates whether to embed the path to the file when the intermediate field is saved.
         /// </summary>
-        /// <value>The index of the embedded file.</value>
-        public int? EmbeddedFileIndex { get; set; }
+        public bool Embed { get; set; }
 
         /// <summary>
         /// Gets the base URI of the path field.
diff --git a/src/WixToolset.Data/IntermediateFieldValue.cs b/src/WixToolset.Data/IntermediateFieldValue.cs
index ca109e7f..9a6b6ef5 100644
--- a/src/WixToolset.Data/IntermediateFieldValue.cs
+++ b/src/WixToolset.Data/IntermediateFieldValue.cs
@@ -76,19 +76,19 @@ namespace WixToolset.Data
                 break;
 
             case JsonObject jsonData:
-                jsonData.TryGetValue("embeddedIndex", out var embeddedIndex);
+                jsonData.TryGetValue("embed", out var embed);
 
                 value = new IntermediateFieldPathValue
                 {
-                    BaseUri = (embeddedIndex == null) ? null : baseUri,
-                    EmbeddedFileIndex = (embeddedIndex == null) ? null : (int?)Convert.ToInt32(embeddedIndex),
+                    BaseUri = (embed != null) ? baseUri : null,
+                    Embed = embed != null,
                     Path = jsonData.GetValueOrDefault<string>("path"),
                 };
                 break;
 
-                // Nothing to do for this case, so leave it out.
-                // case string stringData:
-                //     break;
+            // Nothing to do for this case, so leave it out.
+            // case string stringData:
+            //     break;
             }
 
             var previousValueJson = jsonObject.GetValueOrDefault<JsonObject>("prev");
@@ -117,9 +117,9 @@ namespace WixToolset.Data
 
                 // pathField.BaseUri is set during load, not saved.
 
-                if (pathField.EmbeddedFileIndex.HasValue)
+                if (pathField.Embed)
                 {
-                    jsonData.Add("embeddedIndex", pathField.EmbeddedFileIndex.Value);
+                    jsonData.Add("embed", "true");
                 }
 
                 if (!String.IsNullOrEmpty(pathField.Path))
diff --git a/src/WixToolset.Data/NonClosingStreamWrapper.cs b/src/WixToolset.Data/NonClosingStreamWrapper.cs
deleted file mode 100644
index a2d3be6a..00000000
--- a/src/WixToolset.Data/NonClosingStreamWrapper.cs
+++ /dev/null
@@ -1,84 +0,0 @@
-// Copyright (c) .NET Foundation and contributors. All rights reserved. Licensed under the Microsoft Reciprocal License. See LICENSE.TXT file in the project root for full license information.
-
-namespace WixToolset.Data
-{
-    using System;
-    using System.IO;
-
-    /// <summary>
-    /// Wrapper around stream to prevent other streams (like BinaryReader/Writer) from prematurely
-    /// closing a parent stream.
-    /// </summary>
-    internal class NonClosingStreamWrapper : Stream
-    {
-        private Stream stream;
-
-        public NonClosingStreamWrapper(Stream stream)
-        {
-            this.stream = stream;
-        }
-
-        public override bool CanRead => this.stream.CanRead;
-
-        public override bool CanSeek => this.stream.CanSeek;
-
-        public override bool CanTimeout => this.stream.CanTimeout;
-
-        public override bool CanWrite => this.stream.CanWrite;
-
-        public override long Length => this.stream.Length;
-
-        public override long Position
-        {
-            get => this.stream.Position;
-            set => this.stream.Position = value;
-        }
-
-        public override int ReadTimeout
-        {
-            get => this.stream.ReadTimeout;
-            set => this.stream.ReadTimeout = value;
-        }
-
-        public override int WriteTimeout
-        {
-            get => this.stream.WriteTimeout;
-            set => this.stream.WriteTimeout = value;
-        }
-
-        public override IAsyncResult BeginRead(byte[] buffer, int offset, int count, AsyncCallback callback, object state) => this.stream.BeginRead(buffer, offset, count, callback, state);
-
-        public override IAsyncResult BeginWrite(byte[] buffer, int offset, int count, AsyncCallback callback, object state) => this.stream.BeginWrite(buffer, offset, count, callback, state);
-
-        public override int EndRead(IAsyncResult asyncResult) => this.stream.EndRead(asyncResult);
-
-        public override void EndWrite(IAsyncResult asyncResult) => this.stream.EndWrite(asyncResult);
-
-        public override void Flush() => this.stream.Flush();
-
-        public override int Read(byte[] buffer, int offset, int count) => this.stream.Read(buffer, offset, count);
-
-        public override int ReadByte() => this.stream.ReadByte();
-
-        public override long Seek(long offset, SeekOrigin origin) => this.stream.Seek(offset, origin);
-
-        public override void SetLength(long value) => this.stream.SetLength(value);
-
-        public override void Write(byte[] buffer, int offset, int count) => this.stream.Write(buffer, offset, count);
-
-        public override void WriteByte(byte value) => this.stream.WriteByte(value);
-
-        public override void Close()
-        {
-            // Do not pass through the call since this is what we are overriding.
-        }
-
-        protected override void Dispose(bool disposing)
-        {
-            if (disposing)
-            {
-                this.stream.Flush();
-            }
-        }
-    }
-}
diff --git a/src/WixToolset.Data/WindowsInstaller/Field.cs b/src/WixToolset.Data/WindowsInstaller/Field.cs
index aa359c64..ac8df9a4 100644
--- a/src/WixToolset.Data/WindowsInstaller/Field.cs
+++ b/src/WixToolset.Data/WindowsInstaller/Field.cs
@@ -154,7 +154,7 @@ namespace WixToolset.Data.WindowsInstaller
                     // be enhanced if that ever changes.
                     if (value is int || value.GetType().IsEnum)
                     {
-                        int intValue = (int)value;
+                        var intValue = (int)value;
 
                         // validate the value against the minimum allowed value
                         if (column.MinValue.HasValue && column.MinValue > intValue)
@@ -275,7 +275,7 @@ namespace WixToolset.Data.WindowsInstaller
         /// <param name="writer">XmlWriter where the Field should persist itself as XML.</param>
         internal virtual void Write(XmlWriter writer)
         {
-            writer.WriteStartElement("field", Intermediate.XmlNamespaceUri);
+            writer.WriteStartElement("field", Output.XmlNamespaceUri);
 
             if (this.Modified)
             {
diff --git a/src/WixToolset.Data/WindowsInstaller/ObjectField.cs b/src/WixToolset.Data/WindowsInstaller/ObjectField.cs
index 016693f5..4e654dde 100644
--- a/src/WixToolset.Data/WindowsInstaller/ObjectField.cs
+++ b/src/WixToolset.Data/WindowsInstaller/ObjectField.cs
@@ -130,7 +130,7 @@ namespace WixToolset.Data.WindowsInstaller
         /// <param name="writer">XmlWriter where the Field should persist itself as XML.</param>
         internal override void Write(XmlWriter writer)
         {
-            writer.WriteStartElement("field", Intermediate.XmlNamespaceUri);
+            writer.WriteStartElement("field", Output.XmlNamespaceUri);
 
             if (this.EmbeddedFileIndex.HasValue)
             {
diff --git a/src/WixToolset.Data/WindowsInstaller/Output.cs b/src/WixToolset.Data/WindowsInstaller/Output.cs
index 7f2990f4..ee46c159 100644
--- a/src/WixToolset.Data/WindowsInstaller/Output.cs
+++ b/src/WixToolset.Data/WindowsInstaller/Output.cs
@@ -5,7 +5,6 @@ namespace WixToolset.Data.WindowsInstaller
     using System;
     using System.Collections.Generic;
     using System.Globalization;
-    using System.IO;
     using System.Linq;
     using System.Xml;
 
@@ -16,6 +15,7 @@ namespace WixToolset.Data.WindowsInstaller
     {
         public const string XmlNamespaceUri = "http://wixtoolset.org/schemas/v4/wixout";
         private static readonly Version CurrentVersion = new Version("4.0.0.0");
+        private const string WixOutputStreamName = "wix-wi.xml";
 
         /// <summary>
         /// Creates a new empty output object.
@@ -66,41 +66,29 @@ namespace WixToolset.Data.WindowsInstaller
         /// <returns>Output object.</returns>
         public static Output Load(string path, bool suppressVersionCheck)
         {
-            using (FileStream stream = File.OpenRead(path))
-            using (FileStructure fs = FileStructure.Read(stream))
+            using (var wixout = WixOutput.Read(path))
+            using (var stream = wixout.GetDataStream(WixOutputStreamName))
+            using (var reader = XmlReader.Create(stream, null, wixout.Uri.AbsoluteUri))
             {
-                if (FileFormat.Wixout != fs.FileFormat)
+                try
                 {
-                    throw new WixUnexpectedFileFormatException(path, FileFormat.Wixout, fs.FileFormat);
+                    reader.MoveToContent();
+                    return Output.Read(reader, suppressVersionCheck);
                 }
-
-                Uri uri = new Uri(Path.GetFullPath(path));
-                using (XmlReader reader = XmlReader.Create(fs.GetDataStream(), null, uri.AbsoluteUri))
+                catch (XmlException xe)
                 {
-                    try
-                    {
-                        reader.MoveToContent();
-                        return Output.Read(reader, suppressVersionCheck);
-                    }
-                    catch (XmlException xe)
-                    {
-                        throw new WixCorruptFileException(path, fs.FileFormat, xe);
-                    }
+                    throw new WixCorruptFileException(path, "wixout", xe);
                 }
             }
         }
 
         /// <summary>
-        /// Saves an output to a path on disk.
+        /// Saves an output to a <c>WixOutput</c> container.
         /// </summary>
-        /// <param name="path">Path to save output file to on disk.</param>
-        public void Save(string path)
+        /// <param name="wixout">Container to save to.</param>
+        public void Save(WixOutput wixout)
         {
-            Directory.CreateDirectory(Path.GetDirectoryName(Path.GetFullPath(path)));
-
-            using (FileStream stream = File.Create(path))
-            using (FileStructure fs = FileStructure.Create(stream, FileFormat.Wixout, null))
-            using (XmlWriter writer = XmlWriter.Create(fs.GetDataStream()))
+            using (var writer = XmlWriter.Create(wixout.CreateDataStream(WixOutputStreamName)))
             {
                 writer.WriteStartDocument();
                 this.Write(writer);
@@ -121,8 +109,8 @@ namespace WixToolset.Data.WindowsInstaller
                 throw new XmlException();
             }
 
-            bool empty = reader.IsEmptyElement;
-            Output output = new Output(SourceLineNumber.CreateFromUri(reader.BaseURI));
+            var empty = reader.IsEmptyElement;
+            var output = new Output(SourceLineNumber.CreateFromUri(reader.BaseURI));
             Version version = null;
 
             while (reader.MoveToNextAttribute())
@@ -170,10 +158,10 @@ namespace WixToolset.Data.WindowsInstaller
 
             // loop through the rest of the xml building up the Output object
             TableDefinitionCollection tableDefinitions = null;
-            List<Table> tables = new List<Table>();
+            var tables = new List<Table>();
             if (!empty)
             {
-                bool done = false;
+                var done = false;
 
                 // loop through all the fields in a row
                 while (!done && reader.Read())
@@ -224,7 +212,7 @@ namespace WixToolset.Data.WindowsInstaller
         /// <returns>The table in this output.</returns>
         public Table EnsureTable(TableDefinition tableDefinition)
         {
-            if (!this.Tables.TryGetTable(tableDefinition.Name, out Table table))
+            if (!this.Tables.TryGetTable(tableDefinition.Name, out var table))
             {
                 table = new Table(tableDefinition);
                 this.Tables.Add(table);
@@ -251,19 +239,19 @@ namespace WixToolset.Data.WindowsInstaller
             writer.WriteAttributeString("version", Output.CurrentVersion.ToString());
 
             // Collect all the table definitions and write them.
-            TableDefinitionCollection tableDefinitions = new TableDefinitionCollection();
-            foreach (Table table in this.Tables)
+            var tableDefinitions = new TableDefinitionCollection();
+            foreach (var table in this.Tables)
             {
                 tableDefinitions.Add(table.Definition);
             }
             tableDefinitions.Write(writer);
 
-            foreach (Table table in this.Tables.OrderBy(t => t.Name))
+            foreach (var table in this.Tables.OrderBy(t => t.Name))
             {
                 table.Write(writer);
             }
 
-            foreach (SubStorage subStorage in this.SubStorages)
+            foreach (var subStorage in this.SubStorages)
             {
                 subStorage.Write(writer);
             }
diff --git a/src/WixToolset.Data/WindowsInstaller/Pdb.cs b/src/WixToolset.Data/WindowsInstaller/Pdb.cs
deleted file mode 100644
index 574d5593..00000000
--- a/src/WixToolset.Data/WindowsInstaller/Pdb.cs
+++ /dev/null
@@ -1,155 +0,0 @@
-// Copyright (c) .NET Foundation and contributors. All rights reserved. Licensed under the Microsoft Reciprocal License. See LICENSE.TXT file in the project root for full license information.
-
-namespace WixToolset.Data.WindowsInstaller
-{
-    using System;
-    using System.IO;
-    using System.Xml;
-
-    /// <summary>
-    /// Pdb generated by the binder.
-    /// </summary>
-    public sealed class Pdb
-    {
-        public const string XmlNamespaceUri = "http://wixtoolset.org/schemas/v4/wixpdb";
-        private static readonly Version CurrentVersion = new Version("4.0.0.0");
-
-        /// <summary>
-        /// Gets or sets the output that is a part of this pdb.
-        /// </summary>
-        /// <value>Type of the output.</value>
-        public Output Output { get; set; }
-
-        /// <summary>
-        /// Loads a pdb from a path on disk.
-        /// </summary>
-        /// <param name="path">Path to pdb file saved on disk.</param>
-        /// <param name="suppressVersionCheck">Suppresses wix.dll version mismatch check.</param>
-        /// <returns>Pdb pdb.</returns>
-        public static Pdb Load(string path, bool suppressVersionCheck)
-        {
-            using (FileStream stream = File.OpenRead(path))
-            using (FileStructure fs = FileStructure.Read(stream))
-            {
-                if (FileFormat.Wixpdb != fs.FileFormat)
-                {
-                    throw new WixUnexpectedFileFormatException(path, FileFormat.Wixpdb, fs.FileFormat);
-                }
-
-                Uri uri = new Uri(Path.GetFullPath(path));
-                using (XmlReader reader = XmlReader.Create(fs.GetDataStream(), null, uri.AbsoluteUri))
-                {
-                    try
-                    {
-                        reader.MoveToContent();
-                        return Pdb.Read(reader, suppressVersionCheck);
-                    }
-                    catch (XmlException xe)
-                    {
-                        throw new WixCorruptFileException(path, fs.FileFormat, xe);
-                    }
-                }
-            }
-        }
-
-        /// <summary>
-        /// Saves a pdb to a path on disk.
-        /// </summary>
-        /// <param name="path">Path to save pdb file to on disk.</param>
-        public void Save(string path)
-        {
-            Directory.CreateDirectory(Path.GetDirectoryName(Path.GetFullPath(path)));
-
-            using (FileStream stream = File.Create(path))
-            using (FileStructure fs = FileStructure.Create(stream, FileFormat.Wixpdb, null))
-            using (XmlWriter writer = XmlWriter.Create(fs.GetDataStream()))
-            {
-                writer.WriteStartDocument();
-                this.Write(writer);
-                writer.WriteEndDocument();
-            }
-        }
-
-        /// <summary>
-        /// Processes an XmlReader and builds up the pdb object.
-        /// </summary>
-        /// <param name="reader">Reader to get data from.</param>
-        /// <param name="suppressVersionCheck">Suppresses wix.dll version mismatch check.</param>
-        /// <returns>The Pdb represented by the Xml.</returns>
-        internal static Pdb Read(XmlReader reader, bool suppressVersionCheck)
-        {
-            if ("wixPdb" != reader.LocalName)
-            {
-                throw new XmlException();
-            }
-
-            bool empty = reader.IsEmptyElement;
-            Pdb pdb = new Pdb();
-            Version version = null;
-
-            while (reader.MoveToNextAttribute())
-            {
-                switch (reader.LocalName)
-                {
-                    case "version":
-                        version = new Version(reader.Value);
-                        break;
-                }
-            }
-
-            if (!suppressVersionCheck && null != version && !Pdb.CurrentVersion.Equals(version))
-            {
-                throw new WixException(ErrorMessages.VersionMismatch(SourceLineNumber.CreateFromUri(reader.BaseURI), "wixPdb", version.ToString(), Pdb.CurrentVersion.ToString()));
-            }
-
-            // loop through the rest of the pdb building up the Output object
-            if (!empty)
-            {
-                bool done = false;
-
-                // loop through all the fields in a row
-                while (!done && reader.Read())
-                {
-                    switch (reader.NodeType)
-                    {
-                        case XmlNodeType.Element:
-                            switch (reader.LocalName)
-                            {
-                                case "wixOutput":
-                                    pdb.Output = Output.Read(reader, suppressVersionCheck);
-                                    break;
-                                default:
-                                    throw new XmlException();
-                            }
-                            break;
-                        case XmlNodeType.EndElement:
-                            done = true;
-                            break;
-                    }
-                }
-
-                if (!done)
-                {
-                    throw new XmlException();
-                }
-            }
-
-            return pdb;
-        }
-
-        /// <summary>
-        /// Persists a pdb in an XML format.
-        /// </summary>
-        /// <param name="writer">XmlWriter where the Pdb should persist itself as XML.</param>
-        internal void Write(XmlWriter writer)
-        {
-            writer.WriteStartElement("wixPdb", XmlNamespaceUri);
-
-            writer.WriteAttributeString("version", Pdb.CurrentVersion.ToString());
-
-            this.Output.Write(writer);
-
-            writer.WriteEndElement();
-        }
-    }
-}
diff --git a/src/WixToolset.Data/WindowsInstaller/Row.cs b/src/WixToolset.Data/WindowsInstaller/Row.cs
index af1af628..a267f04b 100644
--- a/src/WixToolset.Data/WindowsInstaller/Row.cs
+++ b/src/WixToolset.Data/WindowsInstaller/Row.cs
@@ -354,7 +354,7 @@ namespace WixToolset.Data.WindowsInstaller
         /// <param name="writer">XmlWriter where the Row should persist itself as XML.</param>
         internal void Write(XmlWriter writer)
         {
-            writer.WriteStartElement("row", Intermediate.XmlNamespaceUri);
+            writer.WriteStartElement("row", Output.XmlNamespaceUri);
 
             if (RowOperation.None != this.Operation)
             {
diff --git a/src/WixToolset.Data/WindowsInstaller/Table.cs b/src/WixToolset.Data/WindowsInstaller/Table.cs
index acb4b6fe..c7f2c8f2 100644
--- a/src/WixToolset.Data/WindowsInstaller/Table.cs
+++ b/src/WixToolset.Data/WindowsInstaller/Table.cs
@@ -291,7 +291,7 @@ namespace WixToolset.Data.WindowsInstaller
                 throw new ArgumentNullException("writer");
             }
 
-            writer.WriteStartElement("table", Intermediate.XmlNamespaceUri);
+            writer.WriteStartElement("table", Output.XmlNamespaceUri);
             writer.WriteAttributeString("name", this.Name);
 
             if (TableOperation.None != this.Operation)
diff --git a/src/WixToolset.Data/WindowsInstaller/TableDefinitionCollection.cs b/src/WixToolset.Data/WindowsInstaller/TableDefinitionCollection.cs
index 619a5206..80303913 100644
--- a/src/WixToolset.Data/WindowsInstaller/TableDefinitionCollection.cs
+++ b/src/WixToolset.Data/WindowsInstaller/TableDefinitionCollection.cs
@@ -227,7 +227,7 @@ namespace WixToolset.Data.WindowsInstaller
         {
             writer.WriteStartElement("tableDefinitions", XmlNamespaceUri);
 
-            foreach (TableDefinition tableDefinition in this.collection.Values.OrderBy(t => t.Name))
+            foreach (var tableDefinition in this.collection.Values.OrderBy(t => t.Name))
             {
                 tableDefinition.Write(writer);
             }
diff --git a/src/WixToolset.Data/WixCorruptFileException.cs b/src/WixToolset.Data/WixCorruptFileException.cs
index f77f0d8a..83c3eb80 100644
--- a/src/WixToolset.Data/WixCorruptFileException.cs
+++ b/src/WixToolset.Data/WixCorruptFileException.cs
@@ -9,7 +9,7 @@ namespace WixToolset.Data
     /// </summary>
     public class WixCorruptFileException : WixException
     {
-        public WixCorruptFileException(string path, FileFormat format, Exception innerException = null)
+        public WixCorruptFileException(string path, string format, Exception innerException = null)
             : base(ErrorMessages.CorruptFileFormat(path, format), innerException)
         {
             this.Path = path;
@@ -19,7 +19,7 @@ namespace WixToolset.Data
         /// <summary>
         /// Gets the actual file format found in the file.
         /// </summary>
-        public FileFormat FileFormat { get; }
+        public string FileFormat { get; }
 
         /// <summary>
         /// Gets the path to the file with unexpected format.
diff --git a/src/WixToolset.Data/WixOutput.cs b/src/WixToolset.Data/WixOutput.cs
new file mode 100644
index 00000000..f27f7c77
--- /dev/null
+++ b/src/WixToolset.Data/WixOutput.cs
@@ -0,0 +1,233 @@
+// Copyright (c) .NET Foundation and contributors. All rights reserved. Licensed under the Microsoft Reciprocal License. See LICENSE.TXT file in the project root for full license information.
+
+namespace WixToolset.Data
+{
+    using System;
+    using System.IO;
+    using System.IO.Compression;
+    using System.Reflection;
+    using System.Text;
+
+    /// <summary>
+    /// Class that understands the standard file structure of the WiX toolset.
+    /// </summary>
+    public class WixOutput : IDisposable
+    {
+        private readonly ZipArchive archive;
+        private bool disposed;
+
+        private WixOutput(Uri uri, ZipArchive archive)
+        {
+            this.Uri = uri;
+            this.archive = archive;
+        }
+
+        public Uri Uri { get; }
+
+        /// <summary>
+        /// Creates a new file structure in memory.
+        /// </summary>
+        /// <returns>Newly created <c>WixOutput</c>.</returns>
+        public static WixOutput Create()
+        {
+            var uri = new Uri("memorystream:");
+
+            var stream = new MemoryStream();
+
+            return WixOutput.Create(uri, stream);
+        }
+
+        /// <summary>
+        /// Creates a new file structure on disk.
+        /// </summary>
+        /// <param name="path">Path to write file structure to.</param>
+        /// <returns>Newly created <c>WixOutput</c>.</returns>
+        public static WixOutput Create(string path)
+        {
+            var uri = new Uri(Path.GetFullPath(path));
+
+            var stream = File.Create(path);
+
+            return WixOutput.Create(uri, stream);
+        }
+
+        /// <summary>
+        /// Creates a new file structure.
+        /// </summary>
+        /// <param name="stream">Stream to write the file structure to.</param>
+        /// <param name="embedFilePaths">Paths to files to embedd in the file structure.</param>
+        /// <returns>Newly created <c>WixOutput</c>.</returns>
+        public static WixOutput Create(Uri uri, Stream stream)
+        {
+            var archive = new ZipArchive(stream, ZipArchiveMode.Update);
+
+            return new WixOutput(uri, archive);
+        }
+
+        /// <summary>
+        /// Loads a wixout from a path on disk.
+        /// </summary>
+        /// <param name="path">Path to wixout file saved on disk.</param>
+        /// <returns>Loaded created <c>WixOutput</c>.</returns>
+        public static WixOutput Read(string path)
+        {
+            var uri = new Uri(Path.GetFullPath(path));
+
+            var stream = File.OpenRead(path);
+
+            return Read(uri, stream);
+        }
+
+        /// <summary>
+        /// Loads a wixout from a path on disk or embedded resource in assembly.
+        /// </summary>
+        /// <param name="baseUri">Uri with local path to wixout file saved on disk or embedded resource in assembly.</param>
+        /// <returns>Loaded created <c>WixOutput</c>.</returns>
+        public static WixOutput Read(Uri baseUri)
+        {
+            // If the embedded files are stored in an assembly resource stream (usually
+            // a .wixlib embedded in a WixExtension).
+            if ("embeddedresource" == baseUri.Scheme)
+            {
+                var assemblyPath = Path.GetFullPath(baseUri.LocalPath);
+                var resourceName = baseUri.Fragment.TrimStart('#');
+
+                var assembly = Assembly.LoadFile(assemblyPath);
+                return WixOutput.Read(assembly, resourceName);
+            }
+            else // normal file (usually a binary .wixlib on disk).
+            {
+                var stream = File.OpenRead(baseUri.LocalPath);
+                return WixOutput.Read(baseUri, stream);
+            }
+        }
+
+        /// <summary>
+        /// Loads a wixout from a assembly resource stream.
+        /// </summary>
+        /// <param name="path">Path to wixout file saved on disk.</param>
+        public static WixOutput Read(Assembly assembly, string resourceName)
+        {
+            var resourceStream = assembly.GetManifestResourceStream(resourceName);
+
+            var uriBuilder = new UriBuilder(assembly.CodeBase)
+            {
+                Scheme = "embeddedresource",
+                Fragment = resourceName
+            };
+
+            return Read(uriBuilder.Uri, resourceStream);
+        }
+
+        /// <summary>
+        /// Reads a file structure from an open stream.
+        /// </summary>
+        /// <param name="stream">Stream to read from.</param>
+        /// <returns>Loaded created <c>WixOutput</c>.</returns>
+        public static WixOutput Read(Uri uri, Stream stream, bool leaveOpen = false)
+        {
+            try
+            {
+                var archive = new ZipArchive(stream, ZipArchiveMode.Read, leaveOpen);
+
+                return new WixOutput(uri, archive);
+            }
+            catch (InvalidDataException)
+            {
+                throw new WixException(ErrorMessages.CorruptFileFormat(uri.AbsoluteUri, "wixout"));
+            }
+        }
+
+        /// <summary>
+        /// Extracts an embedded file.
+        /// </summary>
+        /// <param name="embeddedId">Id to the file to extract.</param>
+        /// <param name="outputPath">Path to write the extracted file to.</param>
+        public void ExtractEmbeddedFile(string embeddedId, string outputPath)
+        {
+            var entry = this.archive.GetEntry(embeddedId);
+
+            if (entry == null)
+            {
+                throw new ArgumentOutOfRangeException(nameof(embeddedId));
+            }
+
+            var folder = Path.GetDirectoryName(outputPath);
+
+            Directory.CreateDirectory(folder);
+
+            entry.ExtractToFile(outputPath);
+        }
+
+        /// <summary>
+        /// Creates a data stream in the wixout.
+        /// </summary>
+        /// <returns>Stream to the data of the file.</returns>
+        public Stream CreateDataStream(string name)
+        {
+            var entry = this.archive.CreateEntry(name);
+
+            return entry.Open();
+        }
+
+        public void ImportDataStream(string name, string path)
+        {
+            this.archive.CreateEntryFromFile(path, name, System.IO.Compression.CompressionLevel.Optimal);
+        }
+
+        /// <summary>
+        /// Gets a non-closing stream to the data of the file.
+        /// </summary>
+        /// <returns>Stream to the data of the file.</returns>
+        public Stream GetDataStream(string name)
+        {
+            var entry = this.archive.GetEntry(name);
+
+            return entry.Open();
+        }
+
+        /// <summary>
+        /// Gets the data of the file as a string.
+        /// </summary>
+        /// <returns>String contents data of the file.</returns>
+        public string GetData(string name)
+        {
+            var entry = this.archive.GetEntry(name);
+
+            var bytes = new byte[entry.Length];
+
+            using (var stream = entry.Open())
+            {
+                stream.Read(bytes, 0, bytes.Length);
+            }
+
+            return Encoding.UTF8.GetString(bytes);
+        }
+
+        /// <summary>
+        /// Disposes of the internal state of the file structure.
+        /// </summary>
+        public void Dispose()
+        {
+            this.Dispose(true);
+            GC.SuppressFinalize(this);
+        }
+
+        /// <summary>
+        /// Disposes of the internsl state of the file structure.
+        /// </summary>
+        /// <param name="disposing">True if disposing.</param>
+        protected virtual void Dispose(bool disposing)
+        {
+            if (!this.disposed)
+            {
+                if (disposing)
+                {
+                    this.archive?.Dispose();
+                }
+            }
+
+            this.disposed = true;
+        }
+    }
+}
diff --git a/src/WixToolset.Data/WixToolset.Data.csproj b/src/WixToolset.Data/WixToolset.Data.csproj
index 95f16c66..0a7efe60 100644
--- a/src/WixToolset.Data/WixToolset.Data.csproj
+++ b/src/WixToolset.Data/WixToolset.Data.csproj
@@ -12,6 +12,10 @@
   </PropertyGroup>
 
   <ItemGroup>
+    <PackageReference Include="System.IO.Compression" Version="4.3.0" />
+  </ItemGroup>
+
+  <ItemGroup>
     <PackageReference Include="Microsoft.SourceLink.GitHub" Version="1.0.0-beta2-18618-05" PrivateAssets="All" />
     <PackageReference Include="Nerdbank.GitVersioning" Version="2.1.65" PrivateAssets="all" />
   </ItemGroup>
diff --git a/src/WixToolset.Data/WixUnexpectedFileFormatException.cs b/src/WixToolset.Data/WixUnexpectedFileFormatException.cs
index 340fb4d7..4bd6ba4a 100644
--- a/src/WixToolset.Data/WixUnexpectedFileFormatException.cs
+++ b/src/WixToolset.Data/WixUnexpectedFileFormatException.cs
@@ -9,7 +9,7 @@ namespace WixToolset.Data
     /// </summary>
     public class WixUnexpectedFileFormatException : WixException
     {
-        public WixUnexpectedFileFormatException(string path, FileFormat expectedFormat, FileFormat format, Exception innerException = null)
+        public WixUnexpectedFileFormatException(string path, string expectedFormat, string format, Exception innerException = null)
             : base(ErrorMessages.UnexpectedFileFormat(path, expectedFormat, format), innerException)
         {
             this.Path = path;
@@ -20,12 +20,12 @@ namespace WixToolset.Data
         /// <summary>
         /// Gets the expected file format.
         /// </summary>
-        public FileFormat ExpectedFileFormat { get; }
+        public string ExpectedFileFormat { get; }
 
         /// <summary>
         /// Gets the actual file format found in the file.
         /// </summary>
-        public FileFormat FileFormat { get; }
+        public string FileFormat { get; }
 
         /// <summary>
         /// Gets the path to the file with unexpected format.
diff --git a/src/test/WixToolsetTest.Data/SerializeFixture.cs b/src/test/WixToolsetTest.Data/SerializeFixture.cs
index 221ca19c..34e50f36 100644
--- a/src/test/WixToolsetTest.Data/SerializeFixture.cs
+++ b/src/test/WixToolsetTest.Data/SerializeFixture.cs
@@ -26,7 +26,7 @@ namespace WixToolsetTest.Data
                 Location = ComponentLocation.Either,
             });
 
-            var intermediate = new Intermediate("TestIntermediate", new[] { section }, null, null);
+            var intermediate = new Intermediate("TestIntermediate", new[] { section }, null);
 
             var path = Path.GetTempFileName();
             intermediate.Save(path);
@@ -64,7 +64,7 @@ namespace WixToolsetTest.Data
 
             section.Tuples.Add(tuple);
 
-            var intermediate = new Intermediate("TestIntermediate", new[] { section }, null, null);
+            var intermediate = new Intermediate("TestIntermediate", new[] { section }, null);
 
             var path = Path.GetTempFileName();
             try
@@ -108,7 +108,7 @@ namespace WixToolsetTest.Data
             var section = new IntermediateSection("test", SectionType.Product, 65001);
             section.Tuples.Add(tuple);
 
-            var intermediate1 = new Intermediate("TestIntermediate", new[] { section }, null, null);
+            var intermediate1 = new Intermediate("TestIntermediate", new[] { section }, null);
 
             // Intermediate #2
             var fieldDefs2 = new[]
@@ -130,7 +130,7 @@ namespace WixToolsetTest.Data
             var section2 = new IntermediateSection("test2", SectionType.Fragment, 65001);
             section2.Tuples.Add(tuple2);
 
-            var intermediate2 = new Intermediate("TestIntermediate2", new[] { section2 }, null, null);
+            var intermediate2 = new Intermediate("TestIntermediate2", new[] { section2 }, null);
 
             // Save
             var path1 = Path.GetTempFileName();
@@ -191,7 +191,7 @@ namespace WixToolsetTest.Data
             var section = new IntermediateSection("test", SectionType.Product, 65001);
             section.Tuples.Add(tuple);
 
-            var intermediate1 = new Intermediate("TestIntermediate", new[] { section }, null, null);
+            var intermediate1 = new Intermediate("TestIntermediate", new[] { section }, null);
 
             // Intermediate #2
             var fieldDefs2 = new[]
@@ -219,7 +219,7 @@ namespace WixToolsetTest.Data
             var section2 = new IntermediateSection("test2", SectionType.Fragment, 65001);
             section2.Tuples.Add(tuple2);
 
-            var intermediate2 = new Intermediate("TestIntermediate2", new[] { section2 }, null, null);
+            var intermediate2 = new Intermediate("TestIntermediate2", new[] { section2 }, null);
 
             // Save
             var path1 = Path.GetTempFileName();
@@ -290,7 +290,7 @@ namespace WixToolsetTest.Data
                 Location = ComponentLocation.Either,
             });
 
-            var intermediate = new Intermediate("TestIntermediate", new[] { section }, localizations.ToDictionary(l => l.Culture), null);
+            var intermediate = new Intermediate("TestIntermediate", new[] { section }, localizations.ToDictionary(l => l.Culture));
 
             var path = Path.GetTempFileName();
             try