#!/usr/bin/env bash
# Retry with exponential backoff - Recommendation from docs/10-best-practices/RECOMMENDATIONS_AND_SUGGESTIONS.md
# Usage: source this file, then: retry_with_backoff 3 2 some_command [args...]
#   $1 = max_attempts, $2 = initial_delay_seconds, rest = command and args

retry_with_backoff() {
  local max_attempts="${1:?Usage: retry_with_backoff MAX_ATTEMPTS INITIAL_DELAY COMMAND [ARGS...]}"
  local delay="${2:?Usage: retry_with_backoff MAX_ATTEMPTS INITIAL_DELAY COMMAND [ARGS...]}"
  shift 2
  local attempt=1

  while [ "$attempt" -le "$max_attempts" ]; do
    if "$@"; then
      return 0
    fi
    if [ "$attempt" -lt "$max_attempts" ]; then
      echo "[WARN] Attempt $attempt failed, retrying in ${delay}s..." >&2
      sleep "$delay"
      delay=$((delay * 2))
    fi
    attempt=$((attempt + 1))
  done
  echo "[ERROR] Failed after $max_attempts attempts" >&2
  return 1
}

# Allow script to be sourced or run (run = execute first non-option args as command)
if [[ "${BASH_SOURCE[0]}" == "${0}" ]]; then
  if [[ $# -ge 3 ]]; then
    retry_with_backoff "$@"
  else
    echo "Usage: $0 MAX_ATTEMPTS INITIAL_DELAY COMMAND [ARGS...]"
    echo "Example: $0 3 2 curl -s -o /dev/null -w '%{http_code}' https://example.com"
    exit 2
  fi
fi