README.md

WpfHexEditor.Core.ByteProvider

Cross-platform byte provider for gigabyte-scale binary files — zero WPF dependency.

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Features

Component	Description
ByteProvider	Ultra-fast file I/O with virtual/physical position mapping, gigabyte-scale support
EditsManager	In-memory edit tracking (modify, insert, delete) without touching the original file
UndoRedoManager	Full undo/redo with batch transactions, coalescence, and description stack
SearchEngine	Boyer-Moore-Horspool pattern search (text, hex, wildcard), parallel for large files
ChangesetSnapshot	Immutable O(e) snapshot of pending edits for serialization and persistence
FileProvider	Stream abstraction (file, memory stream, read-only) with caching
PositionMapper	Virtual/physical offset mapping accounting for inserts and deletes
ByteReader	Intelligent reads with multi-layer caching

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Quick Start

Open a file and read bytes

using WpfHexEditor.Core.Bytes;

var provider = new ByteProvider();
provider.OpenFile("firmware.bin");

// Read 16 bytes at offset 0x100
byte[] data = provider.GetBytes(0x100, 16);

Console.WriteLine($"File size: {provider.VirtualLength} bytes");
Console.WriteLine($"Is open:   {provider.IsOpen}");

Open from a stream or memory buffer

// From any stream
provider.OpenStream(myStream, readOnly: true);

// From a byte array
provider.OpenMemory(new byte[] { 0x4D, 0x5A, 0x90, 0x00 });

Modify bytes with undo/redo

// Modify a single byte
provider.ModifyByte(0x200, 0xFF);

// Modify multiple bytes at once
provider.ModifyBytes(0x200, new byte[] { 0xFF, 0xFE, 0xFD });

// Insert bytes
provider.InsertBytes(0x300, new byte[] { 0x00, 0x01, 0x02 });

// Delete bytes
provider.DeleteBytes(0x400, count: 4);

// Undo / Redo
provider.Undo();
provider.Redo();

Console.WriteLine($"Can undo: {provider.CanUndo}  ({provider.UndoCount} steps)");
Console.WriteLine($"Can redo: {provider.CanRedo}  ({provider.RedoCount} steps)");

Batch undo transactions

// Group multiple edits into a single undo step
provider.BeginUndoTransaction("Fill with zeros");
for (int i = 0; i < 256; i++)
    provider.ModifyByte(0x1000 + i, 0x00);
provider.CommitUndoTransaction();

// Undo reverses all 256 edits in one step
provider.Undo();

Search

using WpfHexEditor.Core.Search.Models;

// Search by byte pattern (MZ header)
var options = new SearchOptions
{
    Pattern = new byte[] { 0x4D, 0x5A },
    StartPosition = 0
};

SearchResult result = provider.Search(options);

foreach (var match in result.Matches)
    Console.WriteLine($"Found at 0x{match.Position:X8}");

// Search by text
SearchResult textResult = provider.SearchText("Copyright", caseSensitive: false);

// Search by hex pattern with wildcard
SearchResult hexResult = provider.SearchHex("4D 5A ?? 00");

Changeset snapshot

using WpfHexEditor.Core.Changesets;

// Capture all pending edits — O(e), never reads the file
ChangesetSnapshot snapshot = provider.GetChangesetSnapshot();

Console.WriteLine($"Has edits       : {snapshot.HasEdits}");
Console.WriteLine($"Modified ranges : {snapshot.Modified.Count}");
Console.WriteLine($"Inserted blocks : {snapshot.Inserted.Count}");
Console.WriteLine($"Deleted ranges  : {snapshot.Deleted.Count}");

foreach (var range in snapshot.Modified)
    Console.WriteLine($"  Modified {range.Values.Length} bytes at 0x{range.Offset:X8}");

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Project Structure

WpfHexEditor.Core.ByteProvider/
├── Bytes/
│   ├── ByteProvider.cs              ← Main entry point
│   ├── ByteProvider.Search.cs       ← Search integration
│   ├── ByteProvider.Changeset.cs    ← Changeset snapshot
│   ├── EditsManager.cs              ← Edit tracking
│   ├── UndoRedoManager.cs           ← Undo/redo stacks
│   ├── FileProvider.cs              ← Stream abstraction
│   ├── PositionMapper.cs            ← Virtual/physical mapping
│   └── ByteReader.cs                ← Cached reads
├── Search/
│   ├── Services/SearchEngine.cs     ← Boyer-Moore-Horspool
│   └── Models/                      ← SearchOptions, SearchResult, SearchMode
├── Services/
│   └── UndoRedoService.cs
└── Changesets/
    └── ChangesetSnapshot.cs         ← ModifiedRange, InsertedBlock, DeletedRange

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What's New in 1.1.0

• New: IUndoAwareEditor interface — editors (HexEditor, CodeEditor) register with the ByteProvider undo stack via a common contract.
• New: HexByteUndoEntry — typed undo entry for individual byte modifications; participates in the shared UndoEngine across editor types.
• New: DocumentBuffer undo wiring — ByteProvider undo/redo events now propagate to IUndoAwareEditor subscribers.
• Test: Regression test suite added — ByteProviderTests, UndoRedoManagerTests, SearchEngineTests, EditsManagerTests, ChangesetSnapshotTests.

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Dependencies

None. Zero external NuGet dependencies. Pure .NET 8.0.

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License

GNU Affero General Public License v3.0 — Copyright 2026 Derek Tremblay. See LICENSE.