#!/bin/bash

# ============================================
# Flutter Learning 项目启动/关闭脚本
# ============================================

APP_NAME="flutter_learning"
APP_DIR="$(cd "$(dirname "$0")" && pwd)"
PORT="${PORT:-3031}"
LOG_FILE="$APP_DIR/app.log"
PID_FILE="$APP_DIR/app.pid"

start() {
  if [ -f "$PID_FILE" ]; then
    pid=$(cat "$PID_FILE")
    if kill -0 "$pid" 2>/dev/null; then
      echo "❌ 服务已在运行中 (PID: $pid)"
      echo "   如需重启请先执行: $0 stop"
      exit 1
    else
      rm -f "$PID_FILE"
    fi
  fi

  echo "🚀 正在启动 $APP_NAME ..."
  echo "   端口: $PORT"
  echo "   日志: $LOG_FILE"

  cd "$APP_DIR" || exit 1
  nohup npm start > "$LOG_FILE" 2>&1 &
  pid=$!
  echo "$pid" > "$PID_FILE"

  sleep 2
  if kill -0 "$pid" 2>/dev/null; then
    echo "✅ 启动成功 (PID: $pid)"
  else
    echo "❌ 启动失败，请查看日志: tail -f $LOG_FILE"
    rm -f "$PID_FILE"
  fi
}

stop() {
  if [ ! -f "$PID_FILE" ]; then
    echo "⚠️  未找到 PID 文件，尝试通过端口查找进程..."
    pid=$(lsof -ti :"$PORT" 2>/dev/null)
    if [ -z "$pid" ]; then
      echo "❌ 未找到运行中的服务"
      exit 1
    fi
  else
    pid=$(cat "$PID_FILE")
  fi

  echo "🛑 正在停止 $APP_NAME (PID: $pid) ..."
  kill "$pid" 2>/dev/null
  sleep 1

  if kill -0 "$pid" 2>/dev/null; then
    echo "   强制终止中..."
    kill -9 "$pid" 2>/dev/null
    sleep 1
  fi

  if ! kill -0 "$pid" 2>/dev/null; then
    echo "✅ 已停止"
    rm -f "$PID_FILE"
  else
    echo "❌ 停止失败"
  fi
}

status() {
  if [ -f "$PID_FILE" ]; then
    pid=$(cat "$PID_FILE")
    if kill -0 "$pid" 2>/dev/null; then
      echo "✅ $APP_NAME 正在运行 (PID: $pid, 端口: $PORT)"
      return 0
    else
      echo "⚠️  发现残留 PID 文件，但进程不存在"
      rm -f "$PID_FILE"
    fi
  fi

  pid=$(lsof -ti :"$PORT" 2>/dev/null)
  if [ -n "$pid" ]; then
    echo "⚠️  端口 $PORT 被其他进程占用 (PID: $pid, 命令: $(ps -p "$pid" -o comm= 2>/dev/null))"
  else
    echo "❌ $APP_NAME 未运行"
  fi
}

restart() {
  stop
  sleep 1
  start
}

case "${1:-start}" in
  start)
    start
    ;;
  stop)
    stop
    ;;
  restart)
    restart
    ;;
  status)
    status
    ;;
  *)
    echo "用法: $0 {start|stop|restart|status}"
    echo ""
    echo "   start   - 后台启动服务 (默认)"
    echo "   stop    - 停止服务"
    echo "   restart - 重启服务"
    echo "   status  - 查看服务状态"
    echo ""
    echo "环境变量:"
    echo "   PORT    - 监听端口 (默认: 3031)"
    exit 1
    ;;
esac