"""Prometheus 指标模块"""

from prometheus_client import Counter, Histogram, Gauge, CollectorRegistry
from functools import wraps
import time
from typing import Callable

# 创建指标注册表
metrics_registry = CollectorRegistry()

# 请求计数器
request_counter = Counter(
    "http_requests_total",
    "Total HTTP requests",
    ["method", "endpoint", "status"],
    registry=metrics_registry,
)

# 请求延迟直方图
request_latency = Histogram(
    "http_request_duration_seconds",
    "HTTP request latency",
    ["method", "endpoint"],
    registry=metrics_registry,
)

# 算法执行计数器
algorithm_counter = Counter(
    "algorithm_executions_total",
    "Total algorithm executions",
    ["algorithm", "status"],
    registry=metrics_registry,
)

# 算法执行延迟
algorithm_latency = Histogram(
    "algorithm_execution_duration_seconds",
    "Algorithm execution latency",
    ["algorithm"],
    registry=metrics_registry,
)

# 当前处理中的请求数
in_progress_requests = Gauge(
    "http_requests_in_progress",
    "Number of HTTP requests in progress",
    registry=metrics_registry,
)


def track_request(method: str, endpoint: str):
    """
    装饰器：跟踪HTTP请求指标

    Args:
        method: HTTP方法
        endpoint: 端点路径
    """

    def decorator(func: Callable):
        @wraps(func)
        async def wrapper(*args, **kwargs):
            in_progress_requests.inc()
            start_time = time.time()

            try:
                result = await func(*args, **kwargs)
                status = "success"
                return result
            except Exception as e:
                status = "error"
                raise e
            finally:
                elapsed = time.time() - start_time
                request_counter.labels(method=method, endpoint=endpoint, status=status).inc()
                request_latency.labels(method=method, endpoint=endpoint).observe(elapsed)
                in_progress_requests.dec()

        return wrapper

    return decorator


def track_algorithm_execution(algorithm_name: str):
    """
    装饰器：跟踪算法执行指标

    Args:
        algorithm_name: 算法名称
    """

    def decorator(func: Callable):
        @wraps(func)
        def wrapper(*args, **kwargs):
            start_time = time.time()

            try:
                result = func(*args, **kwargs)
                status = "success"
                return result
            except Exception as e:
                status = "error"
                raise e
            finally:
                elapsed = time.time() - start_time
                algorithm_counter.labels(algorithm=algorithm_name, status=status).inc()
                algorithm_latency.labels(algorithm=algorithm_name).observe(elapsed)

        return wrapper

    return decorator