import paramiko
import time
import re
from collections import defaultdict
import logging

logger = logging.getLogger(__name__)

# Глобальный словарь для хранения предыдущих значений RX/TX (для расчета за час)
prev_net_stats = {}

def get_ssh_client(host_config):
    """Создает SSH подключение с детальным логированием"""
    client = paramiko.SSHClient()
    client.set_missing_host_key_policy(paramiko.AutoAddPolicy())
    try:
        logger.info(f"🔌 Подключаюсь к {host_config['ip']}:{host_config['port']} как {host_config['user']}")
        client.connect(
            hostname=host_config['ip'],
            port=host_config['port'],
            username=host_config['user'],
            key_filename=host_config['key_path'],
            timeout=10
        )
        logger.info(f"✅ Подключено к {host_config['ip']}")
        return client
    except paramiko.AuthenticationException:
        error_msg = f"❌ Ошибка аутентификации для {host_config['ip']}! Проверь логин или ключ."
        logger.error(error_msg)
        return error_msg
    except paramiko.SSHException as e:
        error_msg = f"❌ SSH ошибка для {host_config['ip']}: {str(e)}"
        logger.error(error_msg)
        return error_msg
    except Exception as e:
        error_msg = f"❌ Неизвестная ошибка для {host_config['ip']}: {str(e)}"
        logger.error(error_msg)
        return error_msg

def exec_cmd(client, command):
    """Выполняет команду и возвращает вывод"""
    try:
        stdin, stdout, stderr = client.exec_command(command, timeout=10)
        return stdout.read().decode('utf-8').strip()
    except Exception as e:
        return f"CMD Error: {str(e)}"

def collect_metrics(host_config):
    """Сбор всех метрик с одного хоста"""
    client = get_ssh_client(host_config)
    if isinstance(client, str):
        return {"error": client, "host": host_config['name'], "ip": host_config['ip']}

    result = {
        "host": host_config['name'],
        "ip": host_config['ip'],
        "metrics": {}
    }

    # 1. CPU загрузка (%)
    cpu_output = exec_cmd(client, "top -bn1 | grep 'Cpu(s)' | awk '{print $2}' | cut -d'%' -f1")
    try:
        result["metrics"]["cpu"] = float(cpu_output.replace(',', '.'))
    except:
        result["metrics"]["cpu"] = 0.0

    # 2. ОЗУ (используется в MB и %)
    mem_output = exec_cmd(client, "free -m | grep Mem")
    parts = re.split(r'\s+', mem_output)
    if len(parts) >= 3:
        total_mem = int(parts[1])
        used_mem = int(parts[2])
        result["metrics"]["mem_used_mb"] = used_mem
        result["metrics"]["mem_percent"] = round((used_mem / total_mem) * 100, 1)
    else:
        result["metrics"]["mem_used_mb"] = 0
        result["metrics"]["mem_percent"] = 0

    # 3. Uptime и Load Average
    uptime_output = exec_cmd(client, "uptime")
    load_avg = re.search(r'load average:\s+([\d.]+),\s+([\d.]+),\s+([\d.]+)', uptime_output)
    if load_avg:
        result["metrics"]["load_1"] = load_avg.group(1)
        result["metrics"]["load_5"] = load_avg.group(2)
        result["metrics"]["load_15"] = load_avg.group(3)
    
    uptime_seconds = exec_cmd(client, "cat /proc/uptime | awk '{print $1}'")
    try:
        uptime_seconds = float(uptime_seconds.split('.')[0])
        days = uptime_seconds // 86400
        hours = (uptime_seconds % 86400) // 3600
        minutes = (uptime_seconds % 3600) // 60
        result["metrics"]["uptime"] = f"{int(days)}d {int(hours)}h {int(minutes)}m"
    except:
        result["metrics"]["uptime"] = "N/A"

    # 4. Сеть (трафик за последний час)
    net_output = exec_cmd(client, "cat /proc/net/dev | tail -n +3 | grep -v lo")
    current_net = {}
    for line in net_output.split('\n'):
        if not line.strip():
            continue
        parts = re.split(r'\s+', line.strip())
        iface = parts[0].replace(':', '')
        rx_bytes = int(parts[1])
        tx_bytes = int(parts[9])
        current_net[iface] = {'rx': rx_bytes, 'tx': tx_bytes}

    global prev_net_stats
    host_key = host_config['ip']
    total_rx_hour = 0
    total_tx_hour = 0

    if host_key in prev_net_stats:
        old_data = prev_net_stats[host_key]
        for iface, vals in current_net.items():
            if iface in old_data:
                delta_rx = vals['rx'] - old_data[iface]['rx']
                delta_tx = vals['tx'] - old_data[iface]['tx']
                if delta_rx > 0:
                    total_rx_hour += delta_rx
                if delta_tx > 0:
                    total_tx_hour += delta_tx

    result["metrics"]["net_rx_mb"] = round(total_rx_hour / (1024 * 1024), 2)
    result["metrics"]["net_tx_mb"] = round(total_tx_hour / (1024 * 1024), 2)
    
    prev_net_stats[host_key] = current_net

    # 5. Диски (iostat %util)
    iostat_output = exec_cmd(client, "iostat -x -k 1 2 | grep -E 'sd[a-z]|vd[a-z]|nvme' | tail -n +3")
    disk_stats = []
    for line in iostat_output.split('\n'):
        if not line.strip():
            continue
        parts = re.split(r'\s+', line.strip())
        if len(parts) >= 14:
            disk_name = parts[0]
            try:
                util = float(parts[-1].replace(',', '.'))
                rps = float(parts[3].replace(',', '.'))
                wps = float(parts[4].replace(',', '.'))
                disk_stats.append({
                    "name": disk_name,
                    "util": util,
                    "rps": rps,
                    "wps": wps
                })
            except:
                pass
    
    disk_stats.sort(key=lambda x: x['util'], reverse=True)
    result["metrics"]["disks"] = disk_stats[:3]

    # 6. Температуры
    temp_output = exec_cmd(client, "sensors -u 2>/dev/null | grep -E 'temp[0-9]+_input|Core' | head -5")
    temps = []
    if temp_output and "Error" not in temp_output:
        for line in temp_output.split('\n'):
            if '_input:' in line:
                val = re.search(r'([\d.]+)', line)
                if val:
                    temps.append(float(val.group(1)))
    result["metrics"]["temps"] = temps

    # 7. Топ-5 процессов по CPU и RAM
    top_cpu = exec_cmd(client, "ps aux --sort=-%cpu | head -6 | tail -5")
    top_mem = exec_cmd(client, "ps aux --sort=-%mem | head -6 | tail -5")
    result["metrics"]["top_cpu"] = top_cpu
    result["metrics"]["top_mem"] = top_mem

    # 8. Логи (ошибки)
    last_logs = exec_cmd(client, "journalctl -p 3 -xn 5 --no-pager 2>/dev/null || dmesg | tail -5")
    result["metrics"]["logs_errors"] = last_logs

    # 9. Fail2ban (УЛУЧШЕННАЯ ВЕРСИЯ)
    # Проверяем статус
    fail2ban_status = exec_cmd(client, "fail2ban-client status 2>/dev/null")
    if not fail2ban_status or "not found" in fail2ban_status:
        # Проверяем, запущен ли процесс
        ps_fail2ban = exec_cmd(client, "ps aux | grep -v grep | grep fail2ban-server")
        if ps_fail2ban:
            fail2ban_status = "✅ Fail2ban запущен (проверь джейлы командой fail2ban-client status)"
        else:
            fail2ban_status = "❌ Fail2ban не установлен или не запущен"
    else:
        # Парсим статус для красивого вывода
        lines = fail2ban_status.split('\n')
        jails_info = []
        for line in lines:
            if '|- Number of jail:' in line or '`- Number of jail:' in line:
                jails_info.append(line.strip())
            if 'Currently banned:' in line:
                jails_info.append(line.strip())
        if jails_info:
            fail2ban_status = "✅ Fail2ban активен\n" + "\n".join(jails_info)
    
    # Логи банов
    fail2ban_logs = exec_cmd(client, "tail -20 /var/log/fail2ban.log 2>/dev/null | grep -E 'BAN|UNBAN' | tail -5 || echo 'Нет записей о банах'")
    
    # Активные баны
    active_bans = exec_cmd(client, "fail2ban-client status 2>/dev/null | grep -A 5 'Currently banned:'")
    if active_bans and "Currently banned:" in active_bans:
        fail2ban_logs += "\n\n🔒 Активные баны:\n" + active_bans
    
    result["metrics"]["fail2ban_status"] = fail2ban_status
    result["metrics"]["fail2ban_logs"] = fail2ban_logs

    # 10. Проверка на OOM
    oom_check = exec_cmd(client, "dmesg | grep -i 'out of memory' | tail -3 || echo 'Нет OOM-событий'")
    if oom_check and "Нет OOM-событий" not in oom_check:
        result["metrics"]["oom"] = oom_check
    else:
        result["metrics"]["oom"] = "✅ Нет OOM-событий"

    client.close()
    return result