Function createCodexFetch

src/services/api/codex-fetch-adapter.ts:746–812

(
  accessToken: string,
)

 * @returns A fetch function that translates Anthropic requests to Codex format
 */
export function createCodexFetch(
  accessToken: string,
): (input: RequestInfo | URL, init?: RequestInit) => Promise<Response> {
  const accountId = extractAccountId(accessToken)

  return async (input: RequestInfo | URL, init?: RequestInit): Promise<Response> => {
    const url = input instanceof Request ? input.url : String(input)

    // Only intercept Anthropic API message calls
    if (!url.includes('/v1/messages')) {
      return globalThis.fetch(input, init)
    }

    // Parse the Anthropic request body
    let anthropicBody: Record<string, unknown>
    try {
      const bodyText =
        init?.body instanceof ReadableStream
          ? await new Response(init.body).text()
          : typeof init?.body === 'string'
            ? init.body
            : '{}'
      anthropicBody = JSON.parse(bodyText)
    } catch {
      anthropicBody = {}
    }

    // Get current token (may have been refreshed)
    const tokens = getCodexOAuthTokens()
    const currentToken = tokens?.accessToken || accessToken

    // Translate to Codex format
    const { codexBody, codexModel } = translateToCodexBody(anthropicBody)

    // Call Codex API
    const codexResponse = await globalThis.fetch(CODEX_BASE_URL, {
      method: 'POST',
      headers: {
        'Content-Type': 'application/json',
        Accept: 'text/event-stream',
        Authorization: `Bearer ${currentToken}`,
        'chatgpt-account-id': accountId,
        originator: 'pi',
        'OpenAI-Beta': 'responses=experimental',
      },
      body: JSON.stringify(codexBody),
    })

    if (!codexResponse.ok) {
      const errorText = await codexResponse.text()
      const errorBody = {
        type: 'error',
        error: {
          type: 'api_error',
          message: `Codex API error (${codexResponse.status}): ${errorText}`,
        },
      }
      return new Response(JSON.stringify(errorBody), {