/**
 * Onboarding state - prefers backend, falls back to localStorage for mock/offline.
 * Hardened: retries on 502/503, never blocks completion.
 */
import { rpcClient } from '@/api/rpc-client'

async function callWithRetry<T>(fn: () => Promise<T>, maxRetries = 3): Promise<T | null> {
  for (let i = 0; i < maxRetries; i++) {
    try {
      return await fn()
    } catch (e) {
      const msg = e instanceof Error ? e.message : ''
      const isRetryable = /502|503|timeout|fetch|network/i.test(msg)
      if (!isRetryable || i === maxRetries - 1) return null
      await new Promise((r) => setTimeout(r, 800 * (i + 1)))
    }
  }
  return null
}

export async function isOnboardingComplete(): Promise<boolean> {
  // Prefer the backend — localStorage gets stale across nodes (a
  // browser that onboarded node A would otherwise treat fresh node B
  // as already-onboarded and skip the wizard entirely). Only fall
  // back to localStorage if the backend is unreachable.
  const result = await callWithRetry(() => rpcClient.isOnboardingComplete(), 2)
  if (result !== null) return result
  return localStorage.getItem('neode_onboarding_complete') === '1'
}

export async function completeOnboarding(): Promise<void> {
  await callWithRetry(() => rpcClient.completeOnboarding(), 3)
  localStorage.setItem('neode_onboarding_complete', '1')
  localStorage.removeItem('neode_onboarding_step')
}

/** Save current onboarding step so refresh resumes where user left off */
export function saveOnboardingStep(step: string): void {
  localStorage.setItem('neode_onboarding_step', step)
}

/** Get the last saved onboarding step, or 'intro' if none */
export function getSavedOnboardingStep(): string {
  return localStorage.getItem('neode_onboarding_step') || 'intro'
}