#!/bin/bash

PORT=$1

# Check if a port number was provided
if [ -z "$PORT" ]; then
  echo "Usage: $0 <port_number>"
  echo "Example: $0 8080"
  exit 1
fi

# Check if lsof is installed
if ! command -v lsof &> /dev/null
then
    echo "Error: 'lsof' command not found. Please install it (e.g., 'sudo apt-get install lsof' or 'brew install lsof')."
    exit 1
fi

echo "Checking if port $PORT is in use..."

# Find the PID using the specified port
# -t: output process IDs only
# -i :PORT: list network files by internet address (port)
PID=$(lsof -t -i :"$PORT" 2>/dev/null)

if [ -n "$PID" ]; then
  echo "Port $PORT is in use by process(es) with PID: $PID"
  read -p "Do you want to kill these processes? (y/N): " response
  if [[ "$response" =~ ^[yY]$ ]]; then
    echo "Killing process(es) $PID..."
    kill -9 "$PID" # -9 sends a SIGKILL signal, ensuring termination
    if [ $? -eq 0 ]; then
      echo "Process(es) $PID killed successfully."
    else
      echo "Failed to kill process(es) $PID."
    fi
  else
    echo "Processes on port $PORT were not killed."
  fi
else
  echo "Port $PORT is free. No process found listening on this port."
fi