import { NextRequest } from 'next/server';
import { createLogger } from '@/lib/logger';
import { apiError, apiSuccess } from '@/lib/server/api-response';
import { fetchPinnedPublicUrl, PublicUrlFetchError } from '@/lib/server/public-url-fetch';
const log = createLogger('Azure Voices');

export const maxDuration = 30;
export const runtime = 'nodejs';

function publicFetchError(error: unknown) {
  if (
    error instanceof PublicUrlFetchError &&
    (error.code === 'INVALID_URL' ||
      error.code === 'BLOCKED_TARGET' ||
      error.code === 'DNS_FAILURE')
  ) {
    return apiError('INVALID_URL', 403, 'Azure endpoint is not an allowed public URL');
  }
  return apiError('UPSTREAM_ERROR', 502, 'Unable to connect to Azure Speech Services');
}

/**
 * Azure TTS Voice List API
 * Fetches available voices from Azure Speech Services
 */
export async function POST(req: NextRequest) {
  let baseUrl: string | undefined;
  try {
    const body = await req.json();
    const { apiKey } = body;
    baseUrl = body.baseUrl;

    if (typeof apiKey !== 'string' || !apiKey) {
      return apiError('MISSING_API_KEY', 400, 'API Key is required');
    }

    if (typeof baseUrl !== 'string' || !baseUrl) {
      return apiError('MISSING_REQUIRED_FIELD', 400, 'Base URL is required');
    }

    let voicesUrl: string;
    try {
      voicesUrl = new URL(
        'cognitiveservices/voices/list',
        baseUrl.endsWith('/') ? baseUrl : `${baseUrl}/`,
      ).href;
    } catch {
      return apiError('INVALID_URL', 403, 'Azure endpoint is not an allowed public URL');
    }

    let pinnedResponse;
    try {
      pinnedResponse = await fetchPinnedPublicUrl(voicesUrl, {
        headers: { 'Ocp-Apim-Subscription-Key': apiKey },
        signal: AbortSignal.timeout(25_000),
        maxResponseBytes: 8 * 1024 * 1024,
      });
    } catch (error) {
      return publicFetchError(error);
    }

    const { response } = pinnedResponse;
    try {
      if (response.status >= 300 && response.status < 400) {
        return apiError('REDIRECT_NOT_ALLOWED', 403, 'Redirects are not allowed');
      }

      if (!response.ok) {
        const errorText = await response.text();
        return apiError(
          'UPSTREAM_ERROR',
          response.status,
          'Failed to fetch voices from Azure',
          errorText || response.statusText,
        );
      }

      const voices = await response.json();

      return apiSuccess({ voices });
    } finally {
      await pinnedResponse.dispose();
    }
  } catch (error) {
    log.error(`Azure voices fetch failed [baseUrl="${baseUrl ?? 'unknown'}"]:`, error);
    return apiError('INTERNAL_ERROR', 500, 'Failed to fetch voices');
  }
}