"""Retry decorator for transient failures."""

import time
from functools import wraps

from werkzeug.exceptions import HTTPException


def retry_on_exception(retries=5, delay_secs=0.0, multiplier=2.0):
    """Call a function and retries if an exception is raised.

    HTTPExceptions (from abort()) are never retried — they represent
    a final HTTP response decision. Only transient errors (e.g. deadlocks,
    lock timeouts) are retried.
    """

    def inner(fn):
        """Call the inner function."""

        @wraps(fn)
        def wrapper(*args, **kwargs):
            """Call the wrapper function."""
            nonlocal delay_secs
            for attempt in range(1, retries + 1):
                try:
                    res = fn(*args, **kwargs)
                    return res
                except HTTPException:
                    raise
                except Exception as e:
                    if attempt >= retries:
                        raise e
                    if delay_secs > 0.0:
                        time.sleep(delay_secs)
                        delay_secs *= multiplier

        return wrapper

    return inner