#!/usr/bin/env bash

set -u

if (( BASH_VERSINFO[0] < 4 || (BASH_VERSINFO[0] == 4 && BASH_VERSINFO[1] < 3) )); then
  echo "[ERROR] start-all.sh requires Bash 4.3 or newer." >&2
  exit 1
fi

SCRIPT_DIR="$(cd -- "$(dirname -- "${BASH_SOURCE[0]}")" && pwd -P)"
BACKEND_SCRIPT="$SCRIPT_DIR/start-backend.sh"
FRONTEND_SCRIPT="$SCRIPT_DIR/start-reactflow.sh"

if [[ ! -x "$BACKEND_SCRIPT" ]]; then
  echo "[ERROR] Backend start script is missing or not executable:" >&2
  echo "        $BACKEND_SCRIPT" >&2
  exit 1
fi

if [[ ! -x "$FRONTEND_SCRIPT" ]]; then
  echo "[ERROR] Frontend start script is missing or not executable:" >&2
  echo "        $FRONTEND_SCRIPT" >&2
  exit 1
fi

BACKEND_PID=""
FRONTEND_PID=""

signal_process_group() {
  local signal="$1"
  local pid="$2"

  [[ -n "$pid" ]] || return 0
  kill "-$signal" -- "-$pid" 2>/dev/null || kill "-$signal" "$pid" 2>/dev/null || true
}

process_group_is_running() {
  local pid="$1"

  [[ -n "$pid" ]] && kill -0 -- "-$pid" 2>/dev/null
}

cleanup() {
  local backend_cleared=false
  local force_kill=false
  local frontend_cleared=false
  local launcher_pid=$$
  local timer_pid

  trap '' INT TERM HUP
  trap - EXIT
  trap 'force_kill=true' ALRM

  signal_process_group TERM "$BACKEND_PID"
  signal_process_group TERM "$FRONTEND_PID"

  (
    sleep 5
    kill -ALRM "$launcher_pid" 2>/dev/null || true
  ) &
  timer_pid=$!

  if [[ -n "$BACKEND_PID" ]]; then
    wait "$BACKEND_PID" 2>/dev/null || true
  fi
  if [[ "$force_kill" == false && -n "$FRONTEND_PID" ]]; then
    wait "$FRONTEND_PID" 2>/dev/null || true
  fi

  while [[ "$force_kill" == false ]]; do
    if [[ "$backend_cleared" == false ]] && ! process_group_is_running "$BACKEND_PID"; then
      backend_cleared=true
    fi
    if [[ "$frontend_cleared" == false ]] && ! process_group_is_running "$FRONTEND_PID"; then
      frontend_cleared=true
    fi
    if [[ "$backend_cleared" == true && "$frontend_cleared" == true ]]; then
      break
    fi
    sleep 0.1
  done

  kill -KILL "$timer_pid" 2>/dev/null || true
  wait "$timer_pid" 2>/dev/null || true

  if [[ "$force_kill" == true ]]; then
    if [[ "$backend_cleared" == false ]] && ! process_group_is_running "$BACKEND_PID"; then
      backend_cleared=true
    fi
    if [[ "$frontend_cleared" == false ]] && ! process_group_is_running "$FRONTEND_PID"; then
      frontend_cleared=true
    fi
    if [[ "$backend_cleared" == false ]]; then
      signal_process_group KILL "$BACKEND_PID"
    fi
    if [[ "$frontend_cleared" == false ]]; then
      signal_process_group KILL "$FRONTEND_PID"
    fi
  fi

  if [[ -n "$BACKEND_PID" ]]; then
    wait "$BACKEND_PID" 2>/dev/null || true
  fi
  if [[ -n "$FRONTEND_PID" ]]; then
    wait "$FRONTEND_PID" 2>/dev/null || true
  fi

  trap - ALRM
}

trap cleanup EXIT
trap 'exit 130' INT
trap 'exit 143' TERM
trap 'exit 129' HUP

echo "Starting FastAPI and ReactFlow..."
echo "Press Ctrl+C to stop both services."
echo

set -m
"$BACKEND_SCRIPT" &
BACKEND_PID=$!
"$FRONTEND_SCRIPT" &
FRONTEND_PID=$!
set +m

wait -n
EXIT_CODE=$?

exit "$EXIT_CODE"