#!/bin/bash

# Versión del script
VERSION="1.0.0"

# Colores y símbolos
RED='\033[0;31m'
GREEN='\033[0;32m'
YELLOW='\033[1;33m'
BLUE='\033[0;34m'
MAGENTA='\033[0;35m'
CYAN='\033[0;36m'
NC='\033[0m'
CHECK_MARK="✓"
CROSS_MARK="✗"
WARN_MARK="⚠️"
LOADING="⏳"
SEARCH="🔍"

VERBOSE=false
STEALTH=false
DELAY=0
SECURITY_SCORE=0
IS_SPOOFABLE=false
SPF_STRICT=false
DMARC_ENFORCED=false

show_banner() {
  echo "    
  ███████╗███╗   ███╗ █████╗ ██╗██╗      ██████╗ ███████╗██╗███╗   ██╗████████╗
  ██╔════╝████╗ ████║██╔══██╗██║██║     ██╔═══██╗██╔════╝██║████╗  ██║╚══██╔══╝
  █████╗  ██╔████╔██║███████║██║██║     ██║   ██║███████╗██║██╔██╗ ██║   ██║   
  ██╔══╝  ██║╚██╔╝██║██╔══██║██║██║     ██║   ██║╚════██║██║██║╚██╗██║   ██║   
  ███████╗██║ ╚═╝ ██║██║  ██║██║███████╗╚██████╔╝███████║██║██║ ╚████║   ██║   
  ╚══════╝╚═╝     ╚═╝╚═╝  ╚═╝╚═╝╚══════╝ ╚═════╝ ╚══════╝╚═╝╚═╝  ╚═══╝   ╚═╝   
  "
  echo -e "${CYAN} Email OSINT Validator v$VERSION${NC}"
  echo -e "${YELLOW} Uso ético - Solo para investigación autorizada${NC}"
  echo
}

show_help() {
  echo "Uso: $0 [opciones] <email>"
  echo
  echo "Opciones:"
  echo "  -v, --verbose    Modo verbose, muestra información detallada"
  echo "  -s, --stealth    Modo sigiloso, más lento pero menos detectable"
  echo "  -d, --delay N    Añade un delay de N segundos entre consultas"
  echo "  -h, --help       Muestra esta ayuda"
  echo "      --version    Muestra la versión"
  echo
  echo "Ejemplos:"
  echo "  $0 usuario@dominio.com"
  echo "  $0 -v usuario@dominio.com"
  echo "  $0 -s -d 2 usuario@dominio.com"
  exit 0
}

show_spinner() {
  local pid=$1
  local delay=0.1
  local spinstr='⠋⠙⠹⠸⠼⠴⠦⠧⠇⠏'
  printf "\r"
  while ps -p $pid > /dev/null 2>&1; do
    local temp=${spinstr#?}
    printf "\r[%c] " "$spinstr"
    local spinstr=$temp${spinstr%"$temp"}
    sleep $delay
  done
  printf "\r   \r"
}

log() {
  local level=$1
  local message=$2
  if [[ $VERBOSE == true ]] || [[ $level != "DEBUG" ]]; then
    case $level in
      "INFO")  echo -e "${GREEN}${CHECK_MARK}${NC} $message";;
      "WARN")  echo -e "${YELLOW}${WARN_MARK}${NC} $message";;
      "ERROR") echo -e "${RED}${CROSS_MARK}${NC} $message";;
      "DEBUG") echo -e "${BLUE}${SEARCH}${NC} $message";;
    esac
  fi
}
analyze_mx_security() {
  local domain=$1
  local security_features=()
  local vulnerabilities=()
  local spf_strict=false
  local dmarc_enforced=false
  local spoofable=false
  local security_score=0
  local max_score=100

  log "DEBUG" "Iniciando análisis de seguridad profundo para $domain"

    log "DEBUG" "Analizando registros SPF..."
    local spf_record=$(host -t TXT "$domain" | grep "v=spf1")
    if [ -n "$spf_record" ]; then
      security_features+=("SPF")
      security_score=$((security_score + 20))

      if [[ $spf_record =~ "-all" ]]; then
        security_features+=("SPF_STRICT")
        spf_strict=true
        security_score=$((security_score + 15))
      elif [[ $spf_record =~ "~all" ]]; then
        security_features+=("SPF_SOFT_FAIL")
        vulnerabilities+=("SPF no es estricto (usa ~all)")
        security_score=$((security_score + 10))
      elif [[ $spf_record =~ "\?all" ]]; then
        vulnerabilities+=("SPF en modo neutral")
        security_score=$((security_score + 5))
      elif [[ $spf_record =~ "\+all" ]]; then
        vulnerabilities+=("SPF permite cualquier remitente")
        spoofable=true
      fi
    else
      vulnerabilities+=("No se encontró registro SPF")
      spoofable=true
    fi

    log "DEBUG" "Analizando política DMARC..."
    local dmarc_record=$(host -t TXT "_dmarc.$domain" | grep "v=DMARC1")
    if [ -n "$dmarc_record" ]; then
      security_features+=("DMARC")
      security_score=$((security_score + 20))

      if [[ $dmarc_record =~ "p=reject" ]]; then
        security_features+=("DMARC_ENFORCED")
        dmarc_enforced=true
        security_score=$((security_score + 15))
      elif [[ $dmarc_record =~ "p=quarantine" ]]; then
        security_features+=("DMARC_QUARANTINE")
        security_score=$((security_score + 10))
      elif [[ $dmarc_record =~ "p=none" ]]; then
        vulnerabilities+=("DMARC en modo monitoreo")
        security_score=$((security_score + 5))
      fi

      if [[ $dmarc_record =~ "pct=100" ]] || [[ ! $dmarc_record =~ "pct=" ]]; then
        security_score=$((security_score + 5))
      else
        local pct=$(echo "$dmarc_record" | grep -oP 'pct=\K[0-9]+')
        vulnerabilities+=("DMARC solo aplicado al $pct% del tráfico")
      fi
    else
      vulnerabilities+=("No se encontró registro DMARC")
      spoofable=true
    fi

    log "DEBUG" "Analizando configuración DKIM..."
    local dkim_selectors=("default" "google" "mail" "email" "key1" "selector1" "selector2")
    local dkim_found=false

    for selector in "${dkim_selectors[@]}"; do
      if host -t TXT "${selector}._domainkey.$domain" 2>/dev/null | grep -q "v=DKIM1"; then
        security_features+=("DKIM")
        security_score=$((security_score + 15))
        dkim_found=true
        break
      fi
    done

    if ! $dkim_found; then
      vulnerabilities+=("No se encontró registro DKIM")
    fi

    log "DEBUG" "Verificando MTA-STS..."
    if host -t TXT "_mta-sts.$domain" 2>/dev/null | grep -q "v=STSv1"; then
      security_features+=("MTA-STS")
      security_score=$((security_score + 10))
    else
      vulnerabilities+=("MTA-STS no configurado")
    fi

    if host -t TXT "_smtp._tls.$domain" 2>/dev/null | grep -q "v=TLSRPTv1"; then
      security_features+=("TLSRPT")
      security_score=$((security_score + 5))
    fi

    if dig "$domain" +dnssec | grep -q "RRSIG"; then
      security_features+=("DNSSEC")
      security_score=$((security_score + 10))
    fi

    cat << EOF
╔════════════════════════════════════════════════════════════════
║ 🔒 Análisis de Seguridad para $domain
╠════════════════════════════════════════════════════════════════
║ 📊 Puntuación de Seguridad: $security_score/$max_score
EOF

    if [ ${#security_features[@]} -gt 0 ]; then
        cat << EOF
║
║ ✅ Características de Seguridad Detectadas:
EOF
        for feature in "${security_features[@]}"; do
            printf "║    - %s\n" "$feature"
        done
    fi

    if [ ${#vulnerabilities[@]} -gt 0 ]; then
        cat << EOF
║
║ ⚠️  Vulnerabilidades Detectadas:
EOF
        for vuln in "${vulnerabilities[@]}"; do
            printf "║    - %s\n" "$vuln"
        done
    fi

    cat << EOF
║
║ 🎯 Estado de Protecciones:
║    - SPF Estricto: $(if $spf_strict; then echo "✅"; else echo "❌"; fi)
║    - DMARC Enforced: $(if $dmarc_enforced; then echo "✅"; else echo "❌"; fi)
║    - Spoofing Posible: $(if $spoofable; then echo "⚠️ SÍ"; else echo "✅ NO"; fi)
╚════════════════════════════════════════════════════════════════
EOF

    SECURITY_SCORE=$security_score
    IS_SPOOFABLE=$spoofable
    SPF_STRICT=$spf_strict
    DMARC_ENFORCED=$dmarc_enforced
}

  fingerprint_server() {
    local response=$1
    local server_info=$(echo "$response" | grep -i "^220" | head -n1)

    if [[ $server_info =~ "Microsoft" ]]; then
      log "INFO" "Servidor detectado: Microsoft Exchange/Office 365"
      [[ $VERBOSE == true ]] && log "DEBUG" "Sistema de correo empresarial Microsoft"
    elif [[ $server_info =~ "Google" ]]; then
      log "INFO" "Servidor detectado: Google Workspace"
      [[ $VERBOSE == true ]] && log "DEBUG" "Sistema de correo Google Workspace"
    elif [[ $server_info =~ "Postfix" ]]; then
      log "INFO" "Servidor detectado: Postfix"
      [[ $VERBOSE == true ]] && log "DEBUG" "Servidor de correo Postfix (Linux)"
    elif [[ $server_info =~ "Exim" ]]; then
      log "INFO" "Servidor detectado: Exim"
      [[ $VERBOSE == true ]] && log "DEBUG" "Servidor de correo Exim"
    elif [[ $server_info =~ "Sendmail" ]]; then
      log "INFO" "Servidor detectado: Sendmail"
      [[ $VERBOSE == true ]] && log "DEBUG" "Servidor de correo Sendmail"
    elif [[ $server_info =~ "Zimbra" ]]; then
      log "INFO" "Servidor detectado: Zimbra"
      [[ $VERBOSE == true ]] && log "DEBUG" "Suite de colaboración Zimbra"
    else
      log "INFO" "Servidor no identificado específicamente"
      [[ $VERBOSE == true ]] && log "DEBUG" "Banner del servidor: $server_info"
    fi
  }

  validate_email() {
    local email=$1
    local domain=$(echo "$email" | cut -d "@" -f 2)
    local our_hostname="email-validator-osint.local"

    log "INFO" "Verificando correo: $email"

    if ! echo "$email" | grep -E "^[A-Za-z0-9._%+-]+@[A-Za-z0-9.-]+\.[A-Za-z]{2,}$" >/dev/null; then
      log "ERROR" "Formato de correo inválido"
      return 1
    fi
    log "INFO" "La sintaxis del correo es correcta"

    log "INFO" "Buscando registros MX..."
    local mx_output=$(host -t MX "$domain")
    if [ $? -ne 0 ]; then
      log "ERROR" "No se encontraron registros MX para $domain"
      return 1
    fi

    log "INFO" "Registros MX encontrados:"
    local primary_mx=""
    local current_priority=999

    while read -r line; do
      if [[ $line =~ "is handled by" ]]; then
        local server=$(echo "$line" | awk '{print $NF}' | sed 's/\.$//')
        local priority=$(echo "$line" | awk '{print $(NF-1)}')
        log "INFO" "MX record encontrado: $server (Prioridad $priority)"

        if [ -z "$primary_mx" ] || [ "$priority" -lt "$current_priority" ]; then
          primary_mx=$server
          current_priority=$priority
        fi
      fi
    done <<< "$mx_output"

    [[ $VERBOSE == true ]] && analyze_mx_security "$domain"

    if [ -n "$primary_mx" ]; then
      [[ $STEALTH == true ]] && sleep $DELAY

      echo -ne "${LOADING} Iniciando diálogo con $primary_mx "

        temp_commands=$(mktemp)
        {
          echo "EHLO $our_hostname"
          echo "MAIL FROM:<validator@$our_hostname>"
          echo "RCPT TO:<$email>"
          echo "QUIT"
        } > "$temp_commands"

        nc -w 10 "$primary_mx" 25 < "$temp_commands" > response.tmp 2>&1 &

        nc_pid=$!
        show_spinner $nc_pid
        wait $nc_pid

        rm -f "$temp_commands"

        echo -e "\r${CHECK_MARK} Diálogo con $primary_mx completado    "
        log "INFO" "Respuestas del servidor:"

        local email_status="válido"
        local problem_description=""
        local valid_response=false

        while read -r line; do
          if [[ $line =~ ^[0-9]{3} ]]; then
            echo "  $line"
            local code=${line:0:3}
            valid_response=true

                if [[ $code == "220" ]] && [[ $VERBOSE == true ]]; then
                  fingerprint_server "$line"
                fi

                case $code in
                  250)
                    if [[ $line =~ "RCPT" ]]; then
                      email_status="válido"
                      log "INFO" "Correo verificado exitosamente"
                    fi
                    ;;
                  421)
                    email_status="no verificable"
                    problem_description="El servidor no está disponible temporalmente"
                    log "WARN" "$problem_description"
                    ;;
                  450|452)
                    email_status="temporalmente no disponible"
                    problem_description="Buzón temporalmente no disponible"
                    log "WARN" "$problem_description"
                    ;;
                  500|501|502|503|504)
                    if [[ $VERBOSE == true ]]; then
                      log "DEBUG" "Código $code: Error de protocolo (normal durante la negociación)"
                    fi
                    ;;
                  550)
                    if [[ $line =~ "RCPT" ]] || [[ $line =~ "user" ]] || [[ $line =~ "recipient" ]]; then
                      email_status="no válido"
                      problem_description="La dirección de correo no existe"
                      log "ERROR" "$problem_description"
                    fi
                    ;;
                  551|553)
                    email_status="no válido"
                    problem_description="La dirección de correo no está permitida"
                    log "ERROR" "$problem_description"
                    ;;
                  554)
                    email_status="no válido"
                    problem_description="Transacción fallida"
                    log "ERROR" "$problem_description"
                    ;;
                esac
          fi
        done < response.tmp

        rm -f response.tmp

        if [[ "$email_status" == "válido" ]]; then
          log "INFO" "El correo $email es válido"
          return 0
        elif [[ "$email_status" == "no válido" ]]; then
          log "ERROR" "El correo $email no es válido"
          [ -n "$problem_description" ] && log "ERROR" "Razón: $problem_description"
          return 1
        else
          log "WARN" "Estado del correo $email: $email_status"
          [ -n "$problem_description" ] && log "WARN" "Razón: $problem_description"
          return 1
        fi
    fi
  }

for cmd in host nc timeout dig bc mktemp; do
  if ! command -v $cmd &> /dev/null; then
    echo -e "${RED}${CROSS_MARK} Error: El comando '$cmd' no está instalado.${NC}"
    echo "  Instala las dependencias necesarias con:"
    echo "  sudo pacman -S bind-tools openbsd-netcat coreutils bc"
    echo "  o"
    echo "  sudo apt install bind9-host netcat coreutils bc"
    exit 1
  fi
done

while [[ $# -gt 0 ]]; do
  case $1 in
    -v|--verbose) VERBOSE=true; shift;;
    -s|--stealth) STEALTH=true; shift;;
    -d|--delay) DELAY="$2"; shift 2;;
    -h|--help) show_help;;
    --version) echo "Email Validator OSINT v$VERSION"; exit 0;;
    *) EMAIL="$1"; shift;;
  esac
done

if [ -z "$EMAIL" ]; then
  show_help
fi

show_banner
validate_email "$EMAIL"
exit_code=$?

if [[ $VERBOSE == true ]] && [[ $exit_code -eq 0 ]]; then
  echo -e "\n${GREEN}🎉 Análisis completado exitosamente${NC}"
  if [[ $SECURITY_SCORE -ge 80 ]]; then
    echo -e "${GREEN}🛡️  El dominio tiene buenas protecciones de seguridad${NC}"
  elif [[ $SECURITY_SCORE -ge 50 ]]; then
    echo -e "${YELLOW}⚠️  El dominio tiene protecciones moderadas${NC}"
  else
    echo -e "${RED}⚠️  El dominio tiene protecciones débiles${NC}"
  fi
fi

exit $exit_code