import type { ProviderId, ProviderInfo, WeatherProvider } from "../types";
import { openMeteo } from "./openmeteo";
import { openWeather } from "./openweather";
import { tomorrowIo } from "./tomorrow";
import { weatherApi } from "./weatherapi";

/**
 * The provider registry.
 * To add a provider: write an adapter that satisfies WeatherProvider,
 * add it here, and add its id to ProviderId in ../types.ts.
 */
export const PROVIDERS: Record<ProviderId, WeatherProvider> = {
  openweather: openWeather,
  weatherapi: weatherApi,
  tomorrow: tomorrowIo,
  openmeteo: openMeteo,
};

/** Order shown in the picker. OpenWeather first because it's the default. */
const DISPLAY_ORDER: ProviderId[] = ["openweather", "weatherapi", "tomorrow", "openmeteo"];

export function isProviderId(value: string): value is ProviderId {
  return value in PROVIDERS;
}

/** A provider is ready if it needs no key, or its key is present. */
export function isReady(provider: WeatherProvider): boolean {
  return provider.envKey === null || Boolean(process.env[provider.envKey]?.trim());
}

/** Provider list for the browser — readiness and limits only, never the keys.
 *  Ready sources lead so the picker starts with working options out of the box. */
export function listProviders(): ProviderInfo[] {
  const all = DISPLAY_ORDER.map((id) => {
    const provider = PROVIDERS[id];
    return {
      id,
      label: provider.label,
      ready: isReady(provider),
      signupUrl: provider.signupUrl,
      ...provider.limits(),
    };
  });
  return [...all.filter((p) => p.ready), ...all.filter((p) => !p.ready)];
}