import type { BackendVersion, VersionStatus } from '@/types'

function isUnknownVersion(version: string | undefined): boolean {
  const normalized = version?.trim().toLowerCase()
  return !normalized || normalized === 'dev' || normalized === 'unknown'
}

export function getVersionStatus(
  frontendVersion: string,
  backendVersion?: BackendVersion,
  hasError = false
): VersionStatus {
  if (hasError) {
    return {
      kind: 'unavailable',
      label: '无法获取后端版本',
      description: '后端版本接口暂时不可用，当前仅展示前端版本。',
    }
  }

  if (!backendVersion || isUnknownVersion(frontendVersion) || isUnknownVersion(backendVersion.version)) {
    return {
      kind: 'unknown',
      label: '无法判断版本',
      description: '当前处于开发构建或版本信息不完整，不判定为版本错误。',
    }
  }

  if (frontendVersion === backendVersion.version) {
    return {
      kind: 'matched',
      label: '版本一致',
      description: '前端和后端来自同一版本构建。',
    }
  }

  return {
    kind: 'mismatched',
    label: '版本不一致',
    description: '前后端版本不同，该状态用于部署诊断，不影响当前功能使用。',
  }
}