#!/usr/bin/env bash
set -e
ROOT="$(cd "$(dirname "$0")" && pwd)"

BACKEND_PORT=18004
FRONTEND_PORT=18003

stop_port() {
  local port=$1
  local label=$2
  local pids
  pids=$(lsof -ti tcp:"$port" 2>/dev/null || true)
  if [ -z "$pids" ]; then
    return 0
  fi
  echo "停止 ${label}（端口 ${port}）..."
  echo "$pids" | xargs kill -TERM 2>/dev/null || true
  sleep 1
  pids=$(lsof -ti tcp:"$port" 2>/dev/null || true)
  if [ -n "$pids" ]; then
    echo "$pids" | xargs kill -KILL 2>/dev/null || true
    sleep 0.5
  fi
}

stop_services() {
  local target="${1:-all}"
  case "$target" in
    backend) stop_port "$BACKEND_PORT" "后端" ;;
    frontend) stop_port "$FRONTEND_PORT" "前端" ;;
    all)
      stop_port "$BACKEND_PORT" "后端"
      stop_port "$FRONTEND_PORT" "前端"
      ;;
  esac
}

ensure_backend_venv() {
  cd "$ROOT/backend"
  if [ ! -d venv ]; then
    python3 -m venv venv
    source venv/bin/activate
    pip install -r requirements.txt -q
  else
    source venv/bin/activate
  fi
}

run_backend() {
  stop_services backend
  ensure_backend_venv
  exec uvicorn main:app --reload --host 0.0.0.0 --port "$BACKEND_PORT"
}

run_frontend() {
  stop_services frontend
  cd "$ROOT/frontend"
  [ -d node_modules ] || npm install
  exec npm run dev -- --host 0.0.0.0 --port "$FRONTEND_PORT"
}

run_all() {
  stop_services all
  ensure_backend_venv
  cd "$ROOT/frontend"
  [ -d node_modules ] || npm install

  trap 'kill $(jobs -p) 2>/dev/null' EXIT INT TERM

  echo "启动后端 http://localhost:${BACKEND_PORT} (API 文档 /docs)"
  (cd "$ROOT/backend" && source venv/bin/activate && uvicorn main:app --reload --host 0.0.0.0 --port "$BACKEND_PORT") &

  echo "启动前端 http://localhost:${FRONTEND_PORT}"
  (cd "$ROOT/frontend" && npm run dev -- --host 0.0.0.0 --port "$FRONTEND_PORT") &

  echo "按 Ctrl+C 停止前后端"
  wait
}

case "${1:-all}" in
  stop) stop_services all ;;
  backend) run_backend ;;
  frontend) run_frontend ;;
  all) run_all ;;
  *)
    echo "用法: ./start.sh [all|backend|frontend|stop]"
    echo ""
    echo "  ./start.sh          # 先停旧进程，再同一终端启动前后端"
    echo "  ./start.sh all      # 同上"
    echo "  ./start.sh backend  # 先停旧后端，再仅启动后端"
    echo "  ./start.sh frontend # 先停旧前端，再仅启动前端"
    echo "  ./start.sh stop     # 仅停止前后端，不启动"
    echo ""
    echo "或按 README 在两个终端分别执行 backend / frontend 下的命令。"
    exit 1
    ;;
esac