"""Request ID, logging, and error handling middleware."""
import logging
import time
import uuid

import structlog
from fastapi import Request
from starlette.middleware.base import BaseHTTPMiddleware



def add_request_id(request: Request) -> str:
    """Extract or generate request ID."""
    request_id = request.headers.get("x-request-id")
    if not request_id:
        request_id = str(uuid.uuid4())
    return request_id


class RequestIDMiddleware(BaseHTTPMiddleware):
    """Add request_id to request state and response headers."""

    async def dispatch(self, request: Request, call_next):
        request_id = add_request_id(request)
        request.state.request_id = request_id

        response = await call_next(request)
        response.headers["x-request-id"] = request_id
        return response


class LoggingMiddleware(BaseHTTPMiddleware):
    """Log request/response with request_id and timing."""

    async def dispatch(self, request: Request, call_next):
        request_id = getattr(request.state, "request_id", str(uuid.uuid4()))
        start = time.perf_counter()

        structlog.contextvars.clear_contextvars()
        structlog.contextvars.bind_contextvars(request_id=request_id)

        response = await call_next(request)

        duration_ms = (time.perf_counter() - start) * 1000
        structlog.get_logger().info(
            "request_completed",
            method=request.method,
            path=request.url.path,
            status=response.status_code,
            duration_ms=round(duration_ms, 2),
        )

        return response


def setup_structlog() -> None:
    """Configure structlog for JSON logging."""
    structlog.configure(
        processors=[
            structlog.contextvars.merge_contextvars,
            structlog.processors.add_log_level,
            structlog.processors.TimeStamper(fmt="iso"),
            structlog.processors.JSONRenderer(),
        ],
        wrapper_class=structlog.make_filtering_bound_logger(logging.INFO),
        context_class=dict,
        logger_factory=structlog.PrintLoggerFactory(),
        cache_logger_on_first_use=True,
    )