Add real desktop notifications and systemd autostart for Gmail tray app

[shrutsureja]

Summary

This branch was originally a minimal skeleton (cmd/notifier + internal/...) that only had config loading and a one-shot IMAP connection test. The ai branch had a much more complete implementation (multi-account IMAP IDLE monitoring, encrypted app-password storage, systray UI, .deb packaging), so this PR:

• Replaces the old skeleton with the ai branch's implementation as the new base
• Adds the one thing that implementation was missing: actual desktop popup notifications. Previously the tray only updated an unread-count badge — nothing ever called notify-send/similar for new mail. Each account's last-seen IMAP UID is now tracked in state.json so genuinely new messages (not the existing unread backlog on first run) trigger a popup showing sender + subject.
• Adds a systemd --user unit (gmail-notifier.service) for autostart on login. The existing .desktop file's X-GNOME-Autostart-enabled=true had no effect since it lived under /usr/share/applications rather than /etc/xdg/autostart or ~/.config/autostart.
• Updates build.sh and README.md accordingly (dependency on libnotify-bin, autostart instructions for both .deb and from-source installs).

Changes

• state.go: track LastUID per account, add GetLastUID/SetLastUID
• imap.go: new Refresh()/checkNewMail() that detects newly-arrived UIDs via UidFetch, fetches sender/subject, and calls back into the UI; replaces ad-hoc GetUnreadCount() call sites
• ui.go: wires the new-mail callback to notify-send
• gmail-notifier.service: new systemd user unit
• build.sh: packages the systemd unit into the .deb, adds libnotify-bin dependency
• README.md: documents notifications behavior and autostart setup

Test plan

• go build ./..., go vet ./..., go test ./... all pass
• gofmt -l . clean
• Manual test on a real Ubuntu desktop: configure a Gmail App Password, confirm tray icon shows unread counts, send a test email and confirm a popup notification appears with correct sender/subject, confirm systemd unit autostarts on login

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Generated by Claude Code

[shrutsureja]

How to test this locally on Ubuntu

1. Install build dependencies

sudo apt-get update
sudo apt-get install -y libayatana-appindicator3-dev libnotify-bin golang

• libayatana-appindicator3-dev — needed to compile the systray icon
• libnotify-bin — provides notify-send, which is what pops up the new-mail notification
• golang — Go 1.21+ is fine; go.mod targets 1.24 but older toolchains that support modules will still build it

2. Get a Gmail App Password (skip if you already have one)

1. Gmail → Settings → Forwarding and POP/IMAP → enable IMAP
2. Google Account → Security → turn on 2-Step Verification (required for App Passwords)
3. Google Account → Security → App passwords → generate one for "Mail" → copy the 16-character password

3. Clone this branch and build

git clone -b claude/ubuntu-email-notifications-bak0b8 https://github.com/shrutsureja/gmail-notifier.git
cd gmail-notifier
go build -o gmail-notifier

This produces a gmail-notifier binary in the current directory. go vet ./... and go test ./... should also pass clean if you want to double check.

4. Configure your account(s)

Create ~/.config/gmail-notifier/config.json (the app also auto-creates an empty one on first run if it doesn't exist):

{
  "accounts": [
    {
      "email": "your-email@gmail.com",
      "password": "your-16-char-app-password"
    }
  ]
}

Enter the App Password in plaintext here — it gets encrypted in place (AES-GCM, key at ~/.config/gmail-notifier/.encryption_key, 0600 perms) the first time the app reads/writes the config.

5. Run it

./gmail-notifier

• A mail icon should appear in your system tray with the total unread count.
• Clicking it shows per-account unread counts, Refresh, and Quit.
• Logs go to ~/.config/gmail-notifier/gmail-notifier.log — useful if the tray icon doesn't show up or login fails.

Important on first run: existing unread mail in your inbox will NOT pop up a notification — that backlog is used to set the "last seen" baseline (state.json) so you don't get flooded with notifications for old mail. Only mail that arrives after that first run triggers a popup.

6. Test the actual notification

With the app running, send yourself a test email (from another account, or via curl/swaks to your monitored address) and wait for IMAP IDLE to pick it up — usually a few seconds. You should see:

• A desktop notification via notify-send with the sender and subject
• The tray unread count incrementing

If no popup appears but the count updates, check that a notification daemon is running (built into GNOME/KDE; minimal WMs like i3/bspwm need something like dunst) and that notify-send hello works standalone.

7. (Optional) Enable autostart

mkdir -p ~/.local/bin && cp gmail-notifier ~/.local/bin/
mkdir -p ~/.config/systemd/user
sed "s|/usr/bin/gmail-notifier|$HOME/.local/bin/gmail-notifier|" gmail-notifier.service > ~/.config/systemd/user/gmail-notifier.service
systemctl --user daemon-reload
systemctl --user enable --now gmail-notifier.service
systemctl --user status gmail-notifier.service   # confirm it's active
journalctl --user -u gmail-notifier.service -f   # tail logs

Things I couldn't verify myself

This PR was built and go build/vet/test verified in a sandboxed container without a graphical session, so I could not confirm the tray icon renders correctly or that a real notify-send popup fires end-to-end against a live Gmail inbox. That real-world check is the main thing left before merging — happy to help debug if anything doesn't behave as described above.

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Generated by Claude Code