import type { CfDnsRecord } from "@cfdm/shared";
import { AppError } from "../../errors.js";
import { parseRetryAfter } from "../cf-retry.js";

export const CF_API_BASE = "https://api.cloudflare.com/client/v4";

export interface CfResponse<T> {
  success: boolean;
  result?: T;
  errors?: Array<{ code: number; message: string }>;
}

export function mapCloudflareFailure(
  operation: string,
  status: number,
  message: string,
): AppError {
  const lower = message.toLowerCase();
  if (status === 401 || status === 403 || lower.includes("authentication")) {
    if (
      operation.includes("workers") ||
      operation.includes("kv_") ||
      operation.includes("accounts")
    ) {
      return AppError.cloudflareAuthFailed(
        "Токену нужны права Account: Workers Scripts Write и Workers KV Storage Write. Zone DNS недостаточно.",
      );
    }
    return AppError.cloudflareAuthFailed(
      "Cloudflare отклонил токен. Проверьте CLOUDFLARE_API_TOKEN.",
    );
  }
  if (status === 429 || lower.includes("rate limit")) {
    return AppError.rateLimited();
  }
  if (lower.includes("zone") && (lower.includes("not found") || status === 404)) {
    return AppError.zoneNotFound();
  }
  if (
    operation.includes("healthcheck") &&
    (lower.includes("plan") ||
      lower.includes("not entitled") ||
      lower.includes("not allowed") ||
      lower.includes("permission"))
  ) {
    return AppError.healthcheckCreateFailed(
      "Cloudflare Health Checks недоступны для этой зоны. Используйте локальные проверки.",
    );
  }
  if (operation.includes("dns") || operation.includes("dns_record")) {
    return AppError.dnsUpdateFailed(`Не удалось обновить DNS в Cloudflare: ${message}`);
  }
  return AppError.cloudflare(`${operation}: ${message}`);
}

export async function handleCfResponse<T>(
  response: Response,
  operation: string,
): Promise<T> {
  if (response.status === 429) {
    const wait = parseRetryAfter(response.headers) ?? 5000;
    throw AppError.rateLimited(
      `Cloudflare временно ограничил запросы. Повторите через ${Math.ceil(wait / 1000)} с.`,
    );
  }

  const body = (await response.json()) as CfResponse<T>;
  if (!body.success) {
    const msg =
      body.errors?.map((e) => e.message).join("; ") ?? "unknown cloudflare error";
    throw mapCloudflareFailure(operation, response.status, msg);
  }
  if (body.result === undefined) {
    throw mapCloudflareFailure(operation, response.status, "empty result");
  }
  return body.result;
}

/** KV PUT / schedules often return `{ success: true }` without `result`. */
export async function handleCfSuccess(
  response: Response,
  operation: string,
): Promise<void> {
  if (response.status === 429) {
    const wait = parseRetryAfter(response.headers) ?? 5000;
    throw AppError.rateLimited(
      `Cloudflare временно ограничил запросы. Повторите через ${Math.ceil(wait / 1000)} с.`,
    );
  }
  const text = await response.text();
  if (!text) {
    if (!response.ok) {
      throw mapCloudflareFailure(operation, response.status, String(response.status));
    }
    return;
  }
  let body: CfResponse<unknown>;
  try {
    body = JSON.parse(text) as CfResponse<unknown>;
  } catch {
    if (!response.ok) {
      throw mapCloudflareFailure(operation, response.status, text.slice(0, 180));
    }
    return;
  }
  if (!body.success) {
    const msg =
      body.errors?.map((e) => e.message).join("; ") ?? "unknown cloudflare error";
    throw mapCloudflareFailure(operation, response.status, msg);
  }
}

export async function cfRequest<T>(
  token: string,
  path: string,
  operation: string,
  init: RequestInit = {},
): Promise<T> {
  const response = await fetch(`${CF_API_BASE}${path}`, {
    ...init,
    headers: {
      Authorization: `Bearer ${token}`,
      ...(init.body ? { "Content-Type": "application/json" } : {}),
      ...init.headers,
    },
    signal: init.signal ?? AbortSignal.timeout(30_000),
  });
  if (response.status >= 500 || response.status === 429) {
    throw mapCloudflareFailure(operation, response.status, String(response.status));
  }
  return handleCfResponse<T>(response, operation);
}

export type DnsRecordResult = CfDnsRecord;