#!/usr/bin/env bash
set -euo pipefail

ROOT_DIR="$(CDPATH= cd -- "$(dirname -- "$0")/.." && pwd)"
RUN_DIR="$ROOT_DIR/run"
PID_FILE="$RUN_DIR/hy-app-monitor.pid"
LOG_FILE="$RUN_DIR/hy-app-monitor.log"
ENV_FILE="${APP_ENV_FILE:-$ROOT_DIR/.env}"
SYSTEMD_SERVICE_NAME="hy-app-monitor.service"

if [ -f "$ENV_FILE" ]; then
  set -a
  # shellcheck disable=SC1090
  . "$ENV_FILE"
  set +a
fi

APP_BIND="${APP_BIND:-0.0.0.0}"
APP_PORT="${APP_PORT:-2026}"
TARGETS_FILE="${TARGETS_FILE:-$ROOT_DIR/config/targets.json}"

if [ -x "$ROOT_DIR/.venv/bin/python" ]; then
  PYTHON_BIN_DEFAULT="$ROOT_DIR/.venv/bin/python"
else
  PYTHON_BIN_DEFAULT="python3"
fi

PYTHON_BIN="${PYTHON_BIN:-$PYTHON_BIN_DEFAULT}"

mkdir -p "$RUN_DIR"

read_pid() {
  if [ -f "$PID_FILE" ]; then
    cat "$PID_FILE"
  fi
}

is_running() {
  local pid
  pid="$(read_pid || true)"
  if [ -z "${pid:-}" ]; then
    return 1
  fi
  kill -0 "$pid" >/dev/null 2>&1
}

has_systemd_unit() {
  if ! command -v systemctl >/dev/null 2>&1; then
    return 1
  fi
  systemctl cat "$SYSTEMD_SERVICE_NAME" >/dev/null 2>&1
}

stop_legacy_process() {
  local pid
  pid="$(read_pid || true)"

  if [ -n "${pid:-}" ] && kill -0 "$pid" >/dev/null 2>&1; then
    kill "$pid" >/dev/null 2>&1 || true
    for _ in $(seq 1 10); do
      if ! kill -0 "$pid" >/dev/null 2>&1; then
        break
      fi
      sleep 1
    done
    kill -9 "$pid" >/dev/null 2>&1 || true
  fi

  rm -f "$PID_FILE"
}