#!/bin/bash
# post-merge: auto-detect changes and reinstall/restart services on the board
set -euo pipefail

REPO="$(cd "$(dirname "$0")/.." && pwd)"
CHANGED=$(git diff HEAD@{1} --name-only 2>/dev/null || echo "")

if [ -z "$CHANGED" ]; then
    exit 0
fi

# Always ensure scripts are executable (git may lose +x on clone/checkout)
sudo chmod +x "$REPO/scripts/"*.py "$REPO/scripts/"*.sh 2>/dev/null || true

SYSTEMD_CHANGED=$(echo "$CHANGED" | grep -c "^system/" || true)
SCRIPT_CHANGED=$(echo "$CHANGED" | grep -c "^scripts/" || true)
SKETCH_CHANGED=$(echo "$CHANGED" | grep -c "^sketch/" || true)

# Reflash MCU if sketch changed
if [ "$SKETCH_CHANGED" -gt 0 ]; then
    echo "[githook:post-merge] MCU sketch changed — reflashing..."
    cd "$REPO" && arduino-cli compile --upload --fqbn arduino:zephyr:unoq sketch/ 2>&1
fi

# Reinstall systemd units if any changed
if [ "$SYSTEMD_CHANGED" -gt 0 ]; then
    echo "[githook:post-merge] Systemd units changed — reinstalling..."
    sudo systemctl daemon-reload
fi

# Restart services if scripts or systemd changed
if [ "$SYSTEMD_CHANGED" -gt 0 ] || [ "$SCRIPT_CHANGED" -gt 0 ]; then
    echo "[githook:post-merge] Scripts/services changed — restarting..."
    sudo chmod +x "$REPO/scripts/"*.py "$REPO/scripts/"*.sh 2>/dev/null || true
    for svc in midi-bridge pd-synth-onboard led-matrix-viz prometheus-exporter; do
        sudo systemctl restart "$svc" 2>/dev/null || true
    done
    echo "[githook:post-merge] Services restarted"
fi