import { refreshRuntimeUrlAuthToken, setRuntimeBearerToken } from '@/lib/runtime-auth';
import { configureRuntimeUrlResolver } from '@/lib/runtime-url';

export type RuntimeEndpointChangedDetail = {
  apiBaseUrl: string;
  previousApiBaseUrl: string;
  runtimeKey: string;
  previousRuntimeKey: string;
};

const RUNTIME_ENDPOINT_CHANGED_EVENT = 'openchamber:runtime-endpoint-changed';

let activeApiBaseUrl = '';
let activeRuntimeKey = '';

const normalizeRuntimeUrlKey = (value: string): string => {
  try {
    const url = new URL(value);
    url.hash = '';
    url.search = '';
    url.pathname = url.pathname.replace(/\/+$/, '') || '/';
    return `url:${url.toString().replace(/\/+$/, '')}`;
  } catch {
    return `url:${value.trim().replace(/\/+$/, '') || 'default'}`;
  }
};

const readInjectedApiBaseUrl = (): string => {
  if (typeof window === 'undefined') return '';
  const injected = (window as typeof window & { __OPENCHAMBER_API_BASE_URL__?: string }).__OPENCHAMBER_API_BASE_URL__;
  return typeof injected === 'string' ? injected.trim() : '';
};

const readInjectedLocalOrigin = (): string => {
  if (typeof window === 'undefined') return '';
  const injected = (window as typeof window & { __OPENCHAMBER_LOCAL_ORIGIN__?: string }).__OPENCHAMBER_LOCAL_ORIGIN__;
  return typeof injected === 'string' ? injected.trim() : '';
};

const sameOrigin = (left: string, right: string): boolean => {
  if (!left || !right) return false;
  try {
    return new URL(left).origin === new URL(right).origin;
  } catch {
    return false;
  }
};

export const getRuntimeApiBaseUrl = (): string => activeApiBaseUrl || readInjectedApiBaseUrl();
export const getRuntimeKey = (): string => {
  if (activeRuntimeKey) return activeRuntimeKey;
  const apiBaseUrl = getRuntimeApiBaseUrl();
  if (sameOrigin(apiBaseUrl, readInjectedLocalOrigin())) return 'local';
  return normalizeRuntimeUrlKey(apiBaseUrl);
};

export const initializeRuntimeEndpoint = (options: { apiBaseUrl?: string | null; runtimeKey?: string | null } = {}): void => {
  if (activeApiBaseUrl || activeRuntimeKey) {
    return;
  }

  const apiBaseUrl = options.apiBaseUrl?.trim() || readInjectedApiBaseUrl();
  if (!apiBaseUrl) {
    return;
  }

  activeApiBaseUrl = apiBaseUrl;
  activeRuntimeKey = options.runtimeKey?.trim() || (sameOrigin(apiBaseUrl, readInjectedLocalOrigin()) ? 'local' : normalizeRuntimeUrlKey(apiBaseUrl));
};

export const switchRuntimeEndpoint = (options: { apiBaseUrl: string; clientToken?: string | null; runtimeKey?: string | null }): void => {
  const apiBaseUrl = options.apiBaseUrl.trim();
  const previousApiBaseUrl = getRuntimeApiBaseUrl();
  const previousRuntimeKey = getRuntimeKey();
  const runtimeKey = options.runtimeKey?.trim() || normalizeRuntimeUrlKey(apiBaseUrl);
  activeApiBaseUrl = apiBaseUrl;
  activeRuntimeKey = runtimeKey;
  if (typeof window !== 'undefined') {
    const runtimeWindow = window as typeof window & {
      __OPENCHAMBER_API_BASE_URL__?: string;
      __OPENCHAMBER_CLIENT_TOKEN__?: string;
    };
    runtimeWindow.__OPENCHAMBER_API_BASE_URL__ = apiBaseUrl;
    runtimeWindow.__OPENCHAMBER_CLIENT_TOKEN__ = options.clientToken || undefined;
  }
  configureRuntimeUrlResolver({ apiBaseUrl, realtimeBaseUrl: apiBaseUrl });
  setRuntimeBearerToken(options.clientToken || null);
  void refreshRuntimeUrlAuthToken(apiBaseUrl).catch(() => {});
  if (typeof window !== 'undefined') {
    window.dispatchEvent(new CustomEvent<RuntimeEndpointChangedDetail>(RUNTIME_ENDPOINT_CHANGED_EVENT, {
      detail: { apiBaseUrl, previousApiBaseUrl, runtimeKey, previousRuntimeKey },
    }));
  }
};

export const subscribeRuntimeEndpointChanged = (callback: (detail: RuntimeEndpointChangedDetail) => void): (() => void) => {
  if (typeof window === 'undefined') return () => {};
  const listener = (event: Event) => {
    callback((event as CustomEvent<RuntimeEndpointChangedDetail>).detail);
  };
  window.addEventListener(RUNTIME_ENDPOINT_CHANGED_EVENT, listener);
  return () => window.removeEventListener(RUNTIME_ENDPOINT_CHANGED_EVENT, listener);
};