src/Massenger.Server: ASP.NET Core 10 Web API + SignalR + SQLite.
src/Massenger.Shared: shared DTO/contracts used by server and client.
src/Massenger.Client: .NET MAUI client targeting net10.0-windows10.0.19041.0 and net10.0-android.

Implemented

user registration and login
JWT access tokens with rotating refresh tokens
secure client-side session persistence
seeded demo accounts and sample chats
user search
direct chats
group chats
channels with owner-only publishing
message history persisted in SQLite
file attachments with metadata persisted in SQLite
voice notes as audio-classified attachments
message edit/delete with realtime updates
authenticated attachment download
real-time message delivery with SignalR
Android push registration API and FCM-based push delivery pipeline
configurable server URL in the client
publishable Windows exe
publishable Android apk

Not Implemented

This is not full Telegram parity. The following are not implemented in this MVP:

calls and video
microphone recording UI for voice notes
inline audio playback controls
stickers and inline media previews
end-to-end encryption
moderation, advanced channel admin roles, multi-device sync edge cases
Windows cloud push notifications

Demo Accounts

alice / demo123
bob / demo123
carol / demo123

These are created automatically on first server start in src/Massenger.Server/Data/massenger.db.

Run

Start the backend:

./scripts/run-server.ps1

Run the Windows client from Visual Studio or CLI:

dotnet build .\src\Massenger.Client\Massenger.Client.csproj -f net10.0-windows10.0.19041.0
.\src\Massenger.Client\bin\Debug\net10.0-windows10.0.19041.0\win-x64\Massenger.Client.exe

Run the Android client from Visual Studio or install the generated APK:

dotnet build .\src\Massenger.Client\Massenger.Client.csproj -f net10.0-android

The default server URL is:

Windows: http://localhost:5099
Android emulator: http://10.0.2.2:5099

On a physical Android device, set the server URL manually in the app to the PC LAN IP, for example http://192.168.1.10:5099.

Publish

Windows EXE:

./scripts/publish-windows.ps1

Android APK:

./scripts/publish-android-apk.ps1

Smoke test against the running backend:

./scripts/smoke-test.ps1

Published Artifacts

Windows EXE: src/Massenger.Client/bin/Release/net10.0-windows10.0.19041.0/win-x64/publish/Massenger.Client.exe
Android APK: src/Massenger.Client/bin/Release/net10.0-android/publish/com.seven.massenger.apk
Signed Android APK: src/Massenger.Client/bin/Release/net10.0-android/publish/com.seven.massenger-Signed.apk

Solutions

XML solution: Massenger.slnx
classic Visual Studio solution: MassengerClassic.sln

Auth Notes

Access tokens are short-lived JWTs.
Refresh tokens are rotated on refresh and stored as hashed server-side sessions.
Logout revokes the active session immediately, and the revoked access token stops working because the server validates the session id (sid) on authenticated requests.
The JWT signing key in src/Massenger.Server/appsettings.json is a development default. Replace it with a strong secret via configuration before any real deployment.

Attachment Notes

Attachments are stored on the server under src/Massenger.Server/Data/Attachments.
Metadata stored for each attachment: original file name, content type, file size, upload time, and owning message.
Audio files are classified as voice notes by MIME type / file extension and use the same secure attachment pipeline.
Attachment content is downloaded through an authenticated API route, not via a public static files directory.

Channel And Message Lifecycle Notes

Channels are broadcast rooms: the creator is the owner, selected users join as subscribers, and only owners can publish.
Message edit/delete is synchronized through SignalR MessageUpdated events.
Delete is implemented as a soft-delete on the message row with attachment cleanup on the server.

Push Setup Notes

Android push in this repo is implemented through Firebase Cloud Messaging HTTP v1 on the server and FirebaseMessagingService on the Android client.
Server-side device registrations are stored in SQLite in the PushDevices table and managed through api/push/devices.
To enable real Android delivery, set Push:FirebaseProjectId and either Push:ServiceAccountJsonPath or Push:ServiceAccountJson in src/Massenger.Server/appsettings.json or environment-specific configuration.
Before building the Android APK, fill src/Massenger.Client/Resources/Raw/firebase.android.json with the Android Firebase values: applicationId, projectId, apiKey, senderId.
If the Firebase configuration is left empty, the app still builds and the server still accepts device registrations, but actual FCM delivery is skipped.
The current Windows desktop target remains unpackaged (WindowsPackageType=None), so this pass does not implement Windows cloud push.