# frozen_string_literal: true

require 'socket'
require 'async'
require 'sequel'
require 'openssl'
require 'securerandom'

# Set up the database
DB = Sequel.sqlite # In-memory database

# Create processors table
DB.create_table :processors do
  primary_key :proto_handler_id
  String :uuid
  String :domain
  Integer :port
end

# Create orchestrators table
DB.create_table :orchestrators do
  primary_key :id
  String :domain
  Integer :port
end

# Create blacklist table
DB.create_table :blacklist do
  primary_key :id
  String :uuid
end

processors = DB[:processors]
orchestrators = DB[:orchestrators]
blacklist = DB[:blacklist]

listen_ip = ENV['LISTEN_IP'] || '0.0.0.0'
listen_port = ENV['LISTEN_PORT'] || 3080

server = TCPServer.new(listen_ip, listen_port)

# This hash will store the recently connected UUIDs with their last validation timestamp
recently_connected = {}

def create_socket(ip, port) # rubocop:disable Metrics/MethodLength
  ip = '127.0.0.1' if ip.downcase == 'loopback'
  if ip =~ Resolv::IPv4::Regex
    TCPSocket.new(ip, port)
  else
    ssl_context = OpenSSL::SSL::SSLContext.new
    ssl_context.verify_mode = OpenSSL::SSL::VERIFY_PEER
    tcp_socket = TCPSocket.new(ip, port)
    ssl_socket = OpenSSL::SSL::SSLSocket.new(tcp_socket, ssl_context)
    ssl_socket.sync_close = true
    ssl_socket.connect
    ssl_socket
  end
end

def handle_input(line, connections, consumer_uuids, blacklisted_ips, client, processors, blacklist, recently_connected) # rubocop:disable Metrics/AbcSize, Metrics/MethodLength, Metrics/CyclomaticComplexity, Metrics/PerceivedComplexity, Metrics/ParameterLists
  command, *args = line.split
  uuid = args.shift if command != 'REGISTER'

  # Check if the UUID is blacklisted
  if blacklisted_ips.include?(client.peeraddr[3]) || blacklist.where(uuid:).count.positive?
    client.puts 'TERMINATE'
    return
  end

  # Check if the UUID is in the recently connected cache
  if recently_connected[uuid] && Time.now - recently_connected[uuid] < 120
    # UUID is recently connected and within 2 minutes, no need to re-validate
  elsif command != 'REGISTER' && (uuid.nil? || !consumer_uuids.values.include?(uuid))
    # UUID is not recently connected or is invalid, add to blacklist
    blacklisted_ips.add(client.peeraddr[3])
    blacklist.insert(uuid:)
    client.puts 'ERROR Unrecognized UUID'
    return
  else
    # UUID is valid, update the recently connected cache
    recently_connected[uuid] = Time.now
  end

  case command
  when 'REGISTER'
    id = processors.max(:proto_handler_id).to_i + 1
    domain, port = args
    uuid = SecureRandom.uuid
    client.puts "UUID #{uuid}"
    consumer_uuids[id] = uuid
    Async do
      processor_connection = create_socket(domain, port)
      connections[id] = processor_connection
      processors.insert(proto_handler_id: id, uuid:, domain:, port:)
    end

  when 'REQUEST'
    # Handle request from orchestrator
    consumer_id, request_type, pcap_chunk_id = args

    # Get the connection for this consumer
    connection = connections[consumer_id]

    # Send the request to the consumer
    connection.puts "REQUEST #{request_type} #{pcap_chunk_id}"

  when 'UPSTATE'
    # Handle upstate from consumer
    consumer_id, state, pcap_chunk_id = args

    # Do something with the state update...
    # For now, we'll just print it out
    puts "Consumer #{consumer_id} is now #{state} for chunk #{pcap_chunk_id}"

  when 'FINISHED'
    # Handle finished from consumer
    consumer_id, pcap_chunk_id = args

    # Do something with the finished message...
    # For now, we'll just print it out
    puts "Consumer #{consumer_id} has finished chunk #{pcap_chunk_id}"

  when 'CHANGE'
    # Handle change from orchestrator
    consumer_id, state, urgency = args

    # Get the connection for this consumer
    connection = connections[consumer_id]

    # Send the change to the consumer
    connection.puts "CHANGE #{state} #{urgency}"

  when 'SHUTDOWN'
    # Handle shutdown from orchestrator
    consumer_id, urgency = args

    # Get the connection for this consumer
    connection = connections[consumer_id]

    # Send the shutdown to the consumer
    connection.puts "SHUTDOWN #{urgency}"

  else
    puts "Unknown command: #{command}"
  end
end

def register_orchestrator(line, orchestrators)
  domain, port = line.split
  id = orchestrators.max(:id).to_i + 1
  orchestrators.insert(id:, domain:, port:)
  puts "Orchestrator registered with domain: #{domain}, port: #{port}"
end

Async do
  loop do
    Async::Task.new do
      client = server.accept

      begin
        line = client.gets
        # Determine if the connection is from an orchestrator for registration
        if is_orchestrator_registration?(line) # Define this method to identify orchestrator registration
          register_orchestrator(line, orchestrators)
        else
          # Here we handle each line of input from the client
          handle_input(line, client, processors, blacklist, recently_connected) # Pass the variables here
        end
      ensure
        # This code will be executed when the fiber is finished, regardless of whether an exception was raised
        client.close
        Async::Task.current.stop
      end
    end
  end
end