# frozen_string_literal: true

# DNS CLI — Gestión del servidor DNS (srvv-dns)
#
# Responsabilidad: Comandos para administración de CoreDNS
#
# Uso:
#   ./adn/tools/run dns help           # Ayuda
#   ./adn/tools/run dns status         # Estado del servidor
#   ./adn/tools/run dns zona           # Listar zona activa
#   ./adn/tools/run dns registros      # Listar todos los registros
#   ./adn/tools/run dns buscar <nombre>
#   ./adn/tools/run dns backup         # Crear backup de zona
#   ./adn/tools/run dns reload         # Forzar reload de CoreDNS

require 'open3'
require 'time'
require_relative '../core/colores'

module ADN
  class SubcomandoDNS
    SSH_HOST = 'rmonla@10.0.10.2'
    SSH_OPTS = '-o StrictHostKeyChecking=no -o ConnectTimeout=10'
    ZONA_PATH = '/docker/coreDNS/zones/frlr.utn.edu.ar.db'
    COREFILE_PATH = '/docker/coreDNS/Corefile'
    ZONA_NAME = 'frlr.utn.edu.ar'

    def initialize(args, logger)
      @args = args
      @logger = logger
    end

    def ejecutar
      if @args.empty? || @args[0] == 'help'
        mostrar_ayuda
        return
      end

      comando = @args[0]

      case comando
      when 'status'
        status
      when 'zona'
        zona
      when 'registros'
        registros
      when 'buscar'
        buscar(@args[1])
      when 'backup'
        backup
      when 'reload'
        reload
      when 'corefile'
        corefile
      else
        puts "#{Color::RED}✗ Comando DNS desconocido: #{comando}#{Color::RESET}"
        mostrar_ayuda
        exit 1
      end
    end

    private

    def mostrar_ayuda
      puts <<~HELP
        #{Color::CYAN}🌐 DNS CLI — Gestión del servidor DNS (srvv-dns)#{Color::RESET}

        #{Color::GREEN}Uso:#{Color::RESET} ./adn/tools/run dns <subcomando> [args]

        #{Color::YELLOW}━━━ Comandos de Consulta ━━━#{Color::RESET}
          #{Color::BOLD}status#{Color::RESET}            Estado del servidor CoreDNS
          #{Color::BOLD}zona#{Color::RESET}              Información de la zona #{ZONA_NAME}
          #{Color::BOLD}registros#{Color::RESET}         Listar todos los registros DNS
          #{Color::BOLD}buscar <nombre>#{Color::RESET}   Buscar registros por nombre

        #{Color::YELLOW}━━━ Comandos de Mantenimiento ━━━#{Color::RESET}
          #{Color::BOLD}backup#{Color::RESET}            Crear backup de la zona
          #{Color::BOLD}reload#{Color::RESET}            Forzar reload de CoreDNS
          #{Color::BOLD}corefile#{Color::RESET}          Mostrar configuración CoreDNS

        #{Color::YELLOW}Ejemplos:#{Color::RESET}
          #{Color::DIM}# Ver estado del servidor#{Color::RESET}
          ./adn/tools/run dns status

          #{Color::DIM}# Listar todos los registros#{Color::RESET}
          ./adn/tools/run dns registros

          #{Color::DIM}# Buscar registros de ns8#{Color::RESET}
          ./adn/tools/run dns buscar ns8

          #{Color::DIM}# Crear backup antes de cambios#{Color::RESET}
          ./adn/tools/run dns backup
      HELP
    end

    def status
      puts "#{Color::CYAN}🌐 Estado del servidor DNS (srvv-dns)#{Color::RESET}\n\n"

      # Verificar conectividad
      print "  Conectividad SSH... "
      if ssh_exec_simple('true')
        puts "#{Color::GREEN}✅ OK#{Color::RESET}"
      else
        puts "#{Color::RED}❌ Fallido#{Color::RESET}"
        return
      end

      # Verificar contenedor CoreDNS
      print "  Contenedor CoreDNS... "
      output = ssh_exec('docker ps --filter "name=coredns" --format "{{.Status}}"')
      if output&.include?('Up')
        puts "#{Color::GREEN}✅ Activo (#{output.strip})#{Color::RESET}"
      else
        puts "#{Color::RED}❌ Inactivo#{Color::RESET}"
      end

      # Verificar puerto 53
      print "  Puerto 53... "
      output = ssh_exec('ss -tuln | grep ":53" | head -1')
      if output&.include?('53')
        puts "#{Color::GREEN}✅ Escuchando#{Color::RESET}"
      else
        puts "#{Color::RED}❌ Cerrado#{Color::RESET}"
      end

      # Verificar zona
      print "  Zona #{ZONA_NAME}... "
      output = ssh_exec("test -f #{ZONA_PATH} && echo 'exists' || echo 'missing'")
      if output&.include?('exists')
        puts "#{Color::GREEN}✅ Existente#{Color::RESET}"
      else
        puts "#{Color::RED}❌ No encontrada#{Color::RESET}"
      end

      # Serial de zona
      print "  Serial de zona... "
      serial = obtener_serial
      if serial
        puts "#{Color::GREEN}#{serial}#{Color::RESET}"
      else
        puts "#{Color::RED}❌ No se pudo leer#{Color::RESET}"
      end

      puts "\n  #{Color::DIM}Última consulta: #{Time.now.strftime('%Y-%m-%d %H:%M:%S')}#{Color::RESET}"
    end

    def zona
      puts "#{Color::CYAN}📋 Zona DNS: #{ZONA_NAME}#{Color::RESET}\n\n"

      serial = obtener_serial
      puts "  SOA Serial: #{serial || 'N/A'}"

      output = ssh_exec("cat #{ZONA_PATH}")
      return unless output

      # Contar registros por tipo
      registros = { 'A' => 0, 'CNAME' => 0, 'MX' => 0, 'TXT' => 0, 'NS' => 0, 'SRV' => 0 }
      output.each_line do |line|
        next if line.start_with?('$', ';')
        registros.each_key do |tipo|
          registros[tipo] += 1 if line.include?(" IN #{tipo} ")
        end
      end

      puts "\n  Registros por tipo:"
      registros.each do |tipo, count|
        puts "    #{tipo}: #{count}" if count > 0
      end

      # Nameservers
      puts "\n  Nameservers:"
      output.each_line do |line|
        puts "    #{line.strip}" if line.include?(' IN NS ')
      end
    end

    def registros
      output = ssh_exec("cat #{ZONA_PATH}")
      return unless output

      puts "#{Color::CYAN}📋 Registros de zona #{ZONA_NAME}#{Color::RESET}\n\n"
      puts "```\n"

      # Imprimir solo líneas de registros (no comentarios ni directivas)
      output.each_line do |line|
        line = line.strip
        next if line.empty? || line.start_with?('$', ';', '(', ')')
        puts line if line.include?(' IN ')
      end

      puts "```"
    end

    def buscar(nombre)
      return puts "#{Color::RED}✗ Falta nombre a buscar#{Color::RESET}" unless nombre

      output = ssh_exec("cat #{ZONA_PATH}")
      return unless output

      puts "#{Color::CYAN}🔍 Buscando '#{nombre}' en #{ZONA_NAME}#{Color::RESET}\n\n"

      encontrados = []
      output.each_line do |line|
        line = line.strip
        next if line.empty? || line.start_with?('$', ';')
        encontrados << line if line.include?(nombre)
      end

      if encontrados.empty?
        puts "  #{Color::RED}No se encontraron registros#{Color::RESET}"
      else
        puts "```\n"
        encontrados.each { |l| puts l }
        puts "```"
      end
    end

    def backup
      timestamp = Time.now.strftime('%y%m%d-%H%M')
      backup_path = "/docker/coreDNS/zones/bkp_#{timestamp}_frlr.utn.edu.ar.db"

      puts "  Creando backup: #{File.basename(backup_path)}..."

      output = ssh_exec("cp #{ZONA_PATH} #{backup_path} && ls -la #{backup_path}")
      if output
        puts "  #{Color::GREEN}✅ Backup creado#{Color::RESET}"
      else
        puts "  #{Color::RED}❌ Error al crear backup#{Color::RESET}"
      end
    end

    def reload
      puts "  Forzando reload de CoreDNS..."

      output = ssh_exec("touch #{ZONA_PATH} && docker kill --signal=HUP coredns 2>/dev/null || echo 'reload manual'")

      if output
        puts "  #{Color::GREEN}✅ Reload solicitado#{Color::RESET}"
        puts "  #{Color::DIM}CoreDNS recargará la zona en ~30s#{Color::RESET}"
      else
        puts "  #{Color::RED}❌ Error al solicitar reload#{Color::RESET}"
      end
    end

    def corefile
      puts "#{Color::CYAN}⚙️  Corefile de CoreDNS#{Color::RESET}\n\n"
      puts "```\n"
      output = ssh_exec("cat #{COREFILE_PATH}")
      puts output if output
      puts "```"
    end

    def ssh_exec(cmd)
      full_cmd = "ssh #{SSH_OPTS} #{SSH_HOST} '#{cmd}'"
      begin
        stdout, stderr, status = Open3.capture3(full_cmd)
        if status.success?
          stdout.strip
        else
          $stderr.puts "#{Color::RED}SSH error: #{stderr.strip}#{Color::RESET}"
          nil
        end
      rescue => e
        $stderr.puts "#{Color::RED}Error en SSH: #{e.message}#{Color::RESET}"
        nil
      end
    end

    def ssh_exec_simple(cmd)
      full_cmd = "ssh #{SSH_OPTS} #{SSH_HOST} '#{cmd}'"
      begin
        _, _, status = Open3.capture3(full_cmd)
        status.success?
      rescue
        false
      end
    end

    def obtener_serial
      output = ssh_exec("grep -A5 'IN SOA' #{ZONA_PATH} | grep -oE '[0-9]{10}' | head -1")
      output
    end
  end
end