import { createAstratoApp } from '@astrato-io/app-runtime';
import { createVisualizationAvailableFields } from '@astrato-io/visualizations/definitions';
import type { DemoView } from './demo-shell.js';
import { createDemoDashboard } from './demo-shell.js';

/** Astrato-hosted adapter. Externally hosted apps supply their own authenticated client. */
export async function startDemo(
  root: HTMLElement,
  plan: {
    title: string;
    scope: string;
    buildViews: (fields: ReturnType<typeof createVisualizationAvailableFields>) => readonly DemoView[];
  },
) {
  root.textContent = 'Preparing your app…';
  let app: Awaited<ReturnType<typeof createAstratoApp>> | undefined;
  try {
    const liveApp = await createAstratoApp();
    app = liveApp;
    const load = liveApp.client.services.engine.fields.getFieldMetadata;
    if (!load) throw new Error('Field metadata is unavailable.');
    const fieldMetadata = await load({ ...liveApp.dataBinding });
    const dashboard = await createDemoDashboard({
      root,
      title: plan.title,
      scope: plan.scope,
      client: liveApp.client,
      dataBinding: { ...liveApp.dataBinding },
      fieldMetadata,
      views: plan.buildViews(createVisualizationAvailableFields(fieldMetadata)),
    });
    return {
      setEmpty: dashboard.setEmpty,
      async destroy() {
        await dashboard.destroy();
        liveApp.destroy();
      },
    };
  } catch (error) {
    app?.destroy();
    root.textContent = error instanceof Error ? error.message : 'App initialization failed.';
    throw error;
  }
}