1 files changed, 81 insertions, 0 deletions
diff --git a/home/bt.nix b/home/bt.nix
new file mode 100644
index 0000000..b41950a
--- /dev/null
+++ b/home/bt.nix
@@ -0,0 +1,81 @@
+{ config, pkgs, ... }:
+{
+
+  systemd.user.services.bt-notify = {
+    Unit = {
+      Description = "Bluetooth Connection & Battery Notifications";
+      After = [ "graphical-session.target" ];
+      ConditionPathExists = "${config.home.homeDirectory}/.local/bin/bt-notify.sh";
+    };
+    Install = {
+      WantedBy = [ "graphical-session.target" ];
+    };
+    Service = {
+      Type = "simple";
+      ExecStart = "${config.home.homeDirectory}/.local/bin/bt-notify.sh";
+      Restart = "always";
+      RestartSec = 5;
+    };
+  };
+
+  home.file."/.local/bin/bt-notify.sh" = {
+    source = pkgs.writeShellScript "bt-notify" ''
+      set -euo pipefail
+
+      # Temporary file to remember which devices were connected last loop
+      STATE_FILE="/tmp/bt-connected-state"
+
+      # Ensure the file exists
+      touch "$STATE_FILE"
+
+      # Listen to BlueZ D-Bus signals AND poll for battery (some devices only report on poll)
+      (
+        # D-Bus listener (connection events)
+        ${pkgs.dbus}/bin/dbus-monitor "interface=org.bluez.Device1,member=PropertiesChanged" --system &
+
+        # Polling loop for battery (runs in background)
+        while true; do
+          ${pkgs.bluez}/bin/bluetoothctl devices | cut -f2 -d' ' | while read -r mac; do
+            info=$(${pkgs.bluez}/bin/bluetoothctl info "$mac")
+            name=$(echo "$info" | grep -i "Alias" | cut -d' ' -f2-)
+            connected=$(echo "$info" | grep -i "Connected" | awk '{print $2}')
+            battery_line=$(echo "$info" | grep -i "Battery Percentage" || true)
+            battery=$(echo "$battery_line" | awk '{print $3}' | tr -d '()')
+
+            # --- Connection change detection ---
+            if [[ "$connected" == "yes" ]] && ! grep -q "^$mac$" "$STATE_FILE"; then
+              ${pkgs.libnotify}/bin/notify-send -a "Bluetooth" "Connected" "$name"
+              echo "$mac" >> "$STATE_FILE"
+            elif [[ "$connected" == "no" ]] && grep -q "^$mac$" "$STATE_FILE"; then
+              ${pkgs.libnotify}/bin/notify-send -a "Bluetooth" "Disconnected" "$name"
+              sed -i "/^$mac$/d" "$STATE_FILE"
+            fi
+
+            # --- Low battery warning ---
+            if [[ -n "$battery" && "$battery" -lt 20 ]]; then
+              ${pkgs.libnotify}/bin/notify-send -u critical -a "Bluetooth" "Low Battery" "$name: ''${battery}%"
+            fi
+          done
+          sleep 10
+        done &
+      ) | while read -r line; do
+        # Parse D-Bus PropertiesChanged for Connected
+        if echo "$line" | grep -q '"Connected"'; then
+          path=$(echo "$line" | grep -oP 'path="\K[^"]+')
+          mac=$(basename "$path")
+          info=$(${pkgs.bluez}/bin/bluetoothctl info "$mac")
+          name=$(echo "$info" | grep -i "Alias" | cut -d' ' -f2-)
+          connected=$(echo "$info" | grep -i "Connected" | awk '{print $2}')
+
+          if [[ "$connected" == "yes" ]] && ! grep -q "^$mac$" "$STATE_FILE"; then
+            ${pkgs.libnotify}/bin/notify-send -a "Bluetooth" "Connected" "$name"
+            echo "$mac" >> "$STATE_FILE"
+          elif [[ "$connected" == "no" ]] && grep -q "^$mac$" "$STATE_FILE"; then
+            ${pkgs.libnotify}/bin/notify-send -a "Bluetooth" "Disconnected" "$name"
+            sed -i "/^$mac$/d" "$STATE_FILE"
+          fi
+        fi
+      done
+    '';
+  };
+}