auth.ts

import { WebStorageStateStore } from "oidc-client-ts";

// Configuration type matching the cognitoAuthConfig structure
type AwsExportsConfig = {
  authority?: string;
  client_id?: string;
  redirect_uri?: string;
  post_logout_redirect_uri?: string;
  response_type?: string;
  scope?: string;
  automaticSilentRenew?: boolean;
  userStore: WebStorageStateStore | undefined;
};

/**
 * Configuration Priority (highest to lowest):
 * 1. Environment variables (VITE_COGNITO_*)
 * 2. aws-exports.json file
 * 3. Default values
 */

// Cache for loaded config
let configCache: AwsExportsConfig | null = null;
let configPromise: Promise<AwsExportsConfig | null> | null = null;

// Load configuration from aws-exports.json at runtime
async function loadAwsConfig(): Promise<AwsExportsConfig | null> {
  if (configCache) {
    return configCache;
  }

  if (configPromise) {
    return configPromise;
  }

  configPromise = (async () => {
    try {
      const response = await fetch("/aws-exports.json");
      if (!response.ok) {
        throw new Error(`Failed to load aws-exports.json: ${response.status}`);
      }
      const config = await response.json();
      configCache = config;
      return config;
    } catch (error) {
      console.error("Failed to load aws-exports.json:", error);
      throw error;
    }
  })();

  return configPromise;
}

// Create auth config factory function that loads config dynamically
export async function createCognitoAuthConfig(): Promise<AwsExportsConfig> {
  const awsConfig = await loadAwsConfig();

  if (awsConfig === null) {
    throw Error("aws-exports.json file not found");
  }

  // Get environment variables
  const userPoolId = import.meta.env.VITE_COGNITO_USER_POOL_ID;
  const clientId = import.meta.env.VITE_COGNITO_CLIENT_ID;
  const region = import.meta.env.VITE_COGNITO_REGION;
  const redirectUri = import.meta.env.VITE_COGNITO_REDIRECT_URI;
  const postLogoutRedirectUri = import.meta.env
    .VITE_COGNITO_POST_LOGOUT_REDIRECT_URI;
  const responseType = import.meta.env.VITE_COGNITO_RESPONSE_TYPE;
  const scope = import.meta.env.VITE_COGNITO_SCOPE;
  const automaticSilentRenew = import.meta.env
    .VITE_COGNITO_AUTOMATIC_SILENT_RENEW;

  // Build authority from environment variables if region and userPoolId are provided
  const envAuthority =
    region && userPoolId
      ? `https://cognito-idp.${region}.amazonaws.com/${userPoolId}`
      : undefined;

  return {
    authority: envAuthority || awsConfig.authority,
    client_id: clientId || awsConfig.client_id,
    redirect_uri: redirectUri || awsConfig.redirect_uri,
    post_logout_redirect_uri:
      postLogoutRedirectUri ||
      redirectUri ||
      awsConfig.post_logout_redirect_uri,
    response_type: responseType || awsConfig.response_type || "code",
    scope: scope || awsConfig.scope || "email openid profile",
    automaticSilentRenew:
      automaticSilentRenew === "false"
        ? false
        : automaticSilentRenew === "true"
          ? true
          : (awsConfig.automaticSilentRenew ?? true),
    userStore:
      typeof window !== "undefined"
        ? new WebStorageStateStore({ store: window.localStorage })
        : undefined,
  };
}

// Synchronous version for backwards compatibility (uses env vars as fallback)
export const cognitoAuthConfig = {
  authority: `https://cognito-idp.${import.meta.env.VITE_COGNITO_REGION}.amazonaws.com/${import.meta.env.VITE_COGNITO_USER_POOL_ID}`,
  client_id: import.meta.env.VITE_COGNITO_CLIENT_ID,
  redirect_uri: import.meta.env.VITE_COGNITO_REDIRECT_URI,
  post_logout_redirect_uri: import.meta.env.VITE_COGNITO_REDIRECT_URI,
  response_type: "code",
  scope: "email openid profile",
  automaticSilentRenew: true,
  userStore:
    typeof window !== "undefined"
      ? new WebStorageStateStore({ store: window.localStorage })
      : undefined,
};