RetryEngine

Pure retry delay calculator. Stateless — no side effects.

Used by platform workers (Android CoroutineWorker, iOS task handler) to determine how long to wait before the next attempt.

Delay formula by policy:

• RetryPolicy.None → 0ms (caller should not retry)

• RetryPolicy.Linear → delayMillis (fixed)

• RetryPolicy.Exponential → initialDelayMillis × 2^retryCount

Example:

val policy = RetryPolicy.Exponential(initialDelayMillis = 5_000)
RetryEngine.nextDelay(0, policy) // 5_000ms
RetryEngine.nextDelay(1, policy) // 10_000ms
RetryEngine.nextDelay(2, policy) // 20_000ms