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());
}

/** Configured providers available to the browser — never exposes keys or unconfigured sources. */
export function listProviders(): ProviderInfo[] {
  return DISPLAY_ORDER.map((id) => PROVIDERS[id])
    .filter(isReady)
    .map((provider) => ({
      id: provider.id,
      label: provider.label,
      ...provider.limits(),
    }));
}