import asyncio
import logging
from aiohttp import web
try:
    from .metrics_collector import MetricsCollector
except ImportError:
    from metrics_collector import MetricsCollector

logger = logging.getLogger(__name__)


class PrometheusServer:
    def __init__(self, host='0.0.0.0', port=9091):
        self.host = host
        self.port = port
        self.metrics_collector = MetricsCollector()
        self.app = web.Application()
        self.setup_routes()
        
    def setup_routes(self):
        """Настройка маршрутов для Prometheus"""
        self.app.router.add_get('/', self.root_handler)
        self.app.router.add_get('/metrics', self.metrics_handler)
        self.app.router.add_get('/health', self.health_handler)
        
    async def root_handler(self, request):
        """Главная страница"""
        return web.Response(
            text="Prometheus Metrics Server\n\n"
                 "Available endpoints:\n"
                 "- /metrics - Prometheus metrics\n"
                 "- /health - Health check",
            content_type='text/plain'
        )
        
    async def health_handler(self, request):
        """Health check endpoint"""
        return web.Response(
            text="OK",
            content_type='text/plain'
        )
        
    async def metrics_handler(self, request):
        """Endpoint для Prometheus метрик"""
        try:
            metrics_data = self.metrics_collector.get_metrics_data()
            prometheus_metrics = self._format_prometheus_metrics(metrics_data)
            
            return web.Response(
                text=prometheus_metrics,
                content_type='text/plain'
            )
            
        except Exception as e:
            logger.error(f"Ошибка при получении метрик: {e}")
            return web.Response(
                text=f"Error: {str(e)}",
                status=500,
                content_type='text/plain'
            )
    
    def _format_prometheus_metrics(self, metrics_data: dict) -> str:
        """Форматирование метрик в Prometheus формат"""
        lines = []
        
        # Системная информация
        lines.append("# HELP system_info System information")
        lines.append("# TYPE system_info gauge")
        lines.append(f"system_info{{os=\"{self.metrics_collector.os_type}\"}} 1")
        
        # CPU метрики
        if 'cpu_usage_percent' in metrics_data:
            lines.append("# HELP cpu_usage_percent CPU usage percentage")
            lines.append("# TYPE cpu_usage_percent gauge")
            lines.append(f"cpu_usage_percent {metrics_data['cpu_usage_percent']}")
            
        if 'load_average_1m' in metrics_data:
            lines.append("# HELP load_average_1m 1 minute load average")
            lines.append("# TYPE load_average_1m gauge")
            lines.append(f"load_average_1m {metrics_data['load_average_1m']}")
            
        if 'load_average_5m' in metrics_data:
            lines.append("# HELP load_average_5m 5 minute load average")
            lines.append("# TYPE load_average_5m gauge")
            lines.append(f"load_average_5m {metrics_data['load_average_5m']}")
            
        if 'load_average_15m' in metrics_data:
            lines.append("# HELP load_average_15m 15 minute load average")
            lines.append("# TYPE load_average_15m gauge")
            lines.append(f"load_average_15m {metrics_data['load_average_15m']}")
        
        # RAM метрики
        if 'ram_usage_percent' in metrics_data:
            lines.append("# HELP ram_usage_percent RAM usage percentage")
            lines.append("# TYPE ram_usage_percent gauge")
            lines.append(f"ram_usage_percent {metrics_data['ram_usage_percent']}")
        
        # Disk метрики
        if 'disk_usage_percent' in metrics_data:
            lines.append("# HELP disk_usage_percent Disk usage percentage")
            lines.append("# TYPE disk_usage_percent gauge")
            lines.append(f"disk_usage_percent {metrics_data['disk_usage_percent']}")
            
        if 'disk_io_percent' in metrics_data:
            lines.append("# HELP disk_io_percent Disk I/O usage percentage")
            lines.append("# TYPE disk_io_percent gauge")
            lines.append(f"disk_io_percent {metrics_data['disk_io_percent']}")
        
        # Swap метрики
        if 'swap_usage_percent' in metrics_data:
            lines.append("# HELP swap_usage_percent Swap usage percentage")
            lines.append("# TYPE swap_usage_percent gauge")
            lines.append(f"swap_usage_percent {metrics_data['swap_usage_percent']}")
        
        # Uptime метрики
        if 'system_uptime_seconds' in metrics_data:
            lines.append("# HELP system_uptime_seconds System uptime in seconds")
            lines.append("# TYPE system_uptime_seconds gauge")
            lines.append(f"system_uptime_seconds {metrics_data['system_uptime_seconds']}")
            
        if 'monitor_uptime_seconds' in metrics_data:
            lines.append("# HELP monitor_uptime_seconds Monitor uptime in seconds")
            lines.append("# TYPE monitor_uptime_seconds gauge")
            lines.append(f"monitor_uptime_seconds {metrics_data['monitor_uptime_seconds']}")
        
        return '\n'.join(lines)
    
    async def start(self):
        """Запуск HTTP сервера"""
        runner = web.AppRunner(self.app)
        await runner.setup()
        
        site = web.TCPSite(runner, self.host, self.port)
        await site.start()
        
        logger.info(f"Prometheus сервер запущен на http://{self.host}:{self.port}")
        
        return runner
    
    async def stop(self, runner):
        """Остановка HTTP сервера"""
        await runner.cleanup()
        logger.info("Prometheus сервер остановлен")