import type { ApiErrorBody } from './types'

export class AgentSdkError extends Error {
  readonly status: number | undefined
  readonly code: string | undefined
  readonly retryAfterMs: number | undefined
  readonly body: string | undefined

  constructor(
    message: string,
    options: {
      status?: number
      code?: string
      retryAfterMs?: number
      body?: string
      cause?: unknown
    } = {},
  ) {
    super(message, options.cause === undefined ? undefined : { cause: options.cause })
    this.name = 'AgentSdkError'
    this.status = options.status
    this.code = options.code
    this.retryAfterMs = options.retryAfterMs
    this.body = options.body
  }

  get isUnauthorized(): boolean {
    return this.status === 401
  }

  get isForbidden(): boolean {
    return this.status === 403
  }

  get isNotFound(): boolean {
    return this.status === 404
  }

  get isRetryable(): boolean {
    if (this.status === undefined) return true
    if (this.status === 429) return true
    return this.status >= 500
  }
}

export async function errorFromResponse(response: Response): Promise<AgentSdkError> {
  const body = await response.text().catch(() => '')
  let parsed: ApiErrorBody | undefined
  try {
    parsed = JSON.parse(body) as ApiErrorBody
  } catch {
    parsed = undefined
  }
  const message = parsed?.message ?? body.trim() ?? response.statusText
  return new AgentSdkError(message, {
    status: response.status,
    code: parsed?.code,
    retryAfterMs: parsed?.retry_after_ms,
    body,
  })
}