import { loadQueueTopologyFromEnv, type QueueTopology } from "@image-platform/queue"
import { loadStorageConfigFromEnv, type StorageConfig } from "@image-platform/storage"

export type WorkerConfig = {
  imgproxyUpstream: URL
  prefetch: number
  queueTopology: QueueTopology
  rabbitmqUrl: string
  storage: StorageConfig
}

export function loadWorkerConfig(env: NodeJS.ProcessEnv = process.env): WorkerConfig {
  return {
    imgproxyUpstream: new URL(getRequiredEnv(env, "IMGPROXY_UPSTREAM")),
    prefetch: parsePositiveInteger(env.WORKER_PREFETCH, 2),
    queueTopology: loadQueueTopologyFromEnv(env),
    rabbitmqUrl: getRequiredEnv(env, "RABBITMQ_URL"),
    storage: loadStorageConfigFromEnv(env),
  }
}

function getRequiredEnv(env: NodeJS.ProcessEnv, name: string) {
  const value = env[name]

  if (!value) {
    throw new Error(`${name} is required`)
  }

  return value
}

function parsePositiveInteger(value: string | undefined, fallback: number) {
  if (!value) {
    return fallback
  }

  const parsed = Number.parseInt(value, 10)

  return Number.isSafeInteger(parsed) && parsed > 0 ? parsed : fallback
}