QuickByte

A C# / WinForms internet download manager, built in the spirit of IDM (Internet Download Manager): multi-connection segmented downloads over HTTP, HTTPS and FTP, live per-connection progress, pause/resume/retry, and a synchronized UI across the main window and any number of open download-detail windows. A Chrome extension takes downloads over from the browser.

Solution layout

QuickByte.sln
Directory.Build.props      Single source of truth for the version and assembly metadata
src/
  QuickByte.Core/         Class library — all business logic, zero WinForms references
    Enums/                DownloadStatus, ConnectionStatus, DownloadCategory,
                            QueueState, ScheduleDays
    Models/                DownloadItem, DownloadSettings, ConnectionInfo, RemoteFileInfo,
                            DownloadQueue, QueueSchedule
    Events/                Event-arg DTOs used for progress/status/connections/list-changed
    Interfaces/           Contracts for every service (see Architecture below)
    Services/              Concrete implementations
      Ftp/                    Minimal FTP/FTPS client: control channel, info provider,
                                segment connection, factory
    Helpers/                ByteFormatter, RangeSplitter, SpeedCalculator, RetryPolicy,
                              FileNameHelper, BandwidthLimiter, ProductVersion,
                              SecretProtector, UrlCredentials
    Streaming/              HLS playlist and DASH manifest parsers, StreamPlan (which
                              pieces to fetch, and which streams to refuse),
                              StreamResolver (the qualities a playlist offers)
    Exceptions/             AuthenticationRequiredException, StreamNotSupportedException

  QuickByte.UI/            WinForms application
    Program.cs             Composition root (wires Core services together)
    AppDispatcher.cs        Marshals Core events onto the UI thread
    SingleInstance.cs       Mutex + named pipe: one copy per user, URLs and queue
                              requests handed to it
    StartupRegistration.cs  "Start with Windows" — the HKCU Run entry for the app
    QueueAgentRegistration.cs  The same, for the scheduler agent below
    AppVersion.cs           Reads the build's version back off its own assembly
    Forms/                  MainForm, DownloadDetailsForm, NewDownloadForm, SettingsForm,
                              QueueManagerForm, UpdateForm
    Controls/                ListViewProgressPainter, ConnectionSegmentsBar, IconFactory,
                              BrandIcon, IcoWriter (shared owner-draw progress bar, the
                              connection start-position/progress bar, and every toolbar/
                              tree/file icon — all drawn with GDI+)
    Assets/                 quickbyte.ico — the one real image file, generated from
                              BrandIcon.cs so the shell icon matches the drawn one

  QuickByte.Cli/           qb.exe — the command-line tool. Parses arguments, talks to the
                             running app over a per-user named pipe, prints the answer.
                             See "Command line" below.

  QuickByte.Agent/         Windowless scheduler that outlives the app: reads queues.json,
    Program.cs               and launches QuickByte when a queue's schedule comes due.
    SchedulerLoop.cs         Starts with the user's session; exits by itself when no
    AgentLog.cs              queue is scheduled. See "Queues and scheduling" below.

browser/
  chrome-extension/        Manifest V3 extension: captures Chrome's downloads and
                             hands them to QuickByte over the loopback bridge

One NuGet package: System.Security.Cryptography.ProtectedData, so FTP and HTTP passwords are not written to disk in plain text. For QuickByte.exe it is compile-time only and deploys nothing — ProtectedData is missing from the net8.0-windows targeting pack QuickByte.Core builds against, but ships inside the Microsoft.WindowsDesktop.App framework the app runs on, so the SDK strips the runtime asset.

The agent is the one exception, and it is worth knowing before wondering why the DLL is in the install folder: being windowless it runs on plain Microsoft.NETCore.App, which does not carry ProtectedData, so the SDK keeps the file. System.Security.Cryptography.ProtectedData.dll therefore ships beside QuickByte.Agent.exe and is named individually in the installer's [Files] list. Everything else is the base class library (System.Net.Http, System.Net.Sockets, System.Text.Json, System.Windows.Forms).

Building and running

Requires the .NET 8 SDK and (to actually run the UI) Windows, since QuickByte.UI targets net8.0-windows with WinForms.

dotnet build QuickByte.sln
dotnet run --project src/QuickByte.UI/QuickByte.UI.csproj

The solution builds three projects: the engine, the WinForms app, and QuickByte.Agent — the scheduler that starts queues while the app is closed.

The agent has to end up beside QuickByte.exe: the app looks for it in its own folder, and the agent finds the app the same way. Building QuickByte.UI puts it there — its CopySchedulerAgent target copies the agent's output into the app's, and fails the build rather than copying nothing, because a scheduler that is silently absent is indistinguishable from one that is broken. The installer's [Files] list then packages it from that same folder. Nothing needs doing by hand in either place.

A copy that somehow ships without it still schedules queues for as long as its window (or tray icon) is there, and the queue window says exactly that rather than promising something it cannot do.

QuickByte.Core alone targets plain net8.0 and will build/test on any OS.

This is the beginning of the README. Read the rest at the original. Read the full README ↗