#!/bin/bash
# 01-macos-notification.sh — show a native macOS banner when HearthGate
# fires a connect / disconnect event.
#
# Why you might want this:
#   The simplest possible "someone connected" alert. The banner appears in
#   the top-right of the screen via Notification Center, no third-party
#   service required, no internet, no setup. If you only ever install one
#   HearthGate hook, this is it.
#
# Setup:
#   Make the script executable, then add it from HearthGate's Hooks tab.
#   Full guide: https://codnamacs.com/hearthgate/help/features/hooks
#
# Environment HearthGate provides (you do not need to set these):
#   HEARTHGATE_EVENT                 — on-connect | after-connect | on-disconnect | after-disconnect
#   HEARTHGATE_SESSION_DURATION_SEC  — only on disconnect events; how long the session ran
#
# Test it without a real SSH connection:
#   HEARTHGATE_EVENT=on-connect ./01-macos-notification.sh
#   HEARTHGATE_EVENT=on-disconnect HEARTHGATE_SESSION_DURATION_SEC=125 ./01-macos-notification.sh

set -euo pipefail

EVENT="${HEARTHGATE_EVENT:-${1:-unknown}}"
DURATION_SEC="${HEARTHGATE_SESSION_DURATION_SEC:-}"

# Format the duration in a human-friendly way: "2m 5s" beats "125".
format_duration() {
    local secs="$1"
    if [ "$secs" -lt 60 ]; then
        echo "${secs}s"
    elif [ "$secs" -lt 3600 ]; then
        echo "$((secs / 60))m $((secs % 60))s"
    else
        echo "$((secs / 3600))h $(((secs % 3600) / 60))m"
    fi
}

notify() {
    local message="$1"
    # `display notification` lives in osascript so we never have to install
    # anything. The title shows up bold; subtitle is one line below.
    osascript -e "display notification \"${message}\" with title \"HearthGate\" sound name \"Tink\""
}

case "$EVENT" in
    on-connect|after-connect)
        notify "Remote session started"
        ;;
    on-disconnect|after-disconnect)
        if [ -n "$DURATION_SEC" ]; then
            notify "Session ended after $(format_duration "$DURATION_SEC")"
        else
            notify "Session ended"
        fi
        ;;
    *)
        # Unknown event — log so the user can debug, but do not fail. A non-
        # zero exit code would mark the hook as "errored" in HearthGate's UI.
        echo "macos-notification: unrecognised event '$EVENT'" >&2
        ;;
esac