import { getConfig } from "../config/store.ts";
import { FETCH_PROVIDER_IDS, type FetchProviderId } from "./provider.ts";

export interface FetchRouting {
	providers: FetchProviderId[];
	allowRemoteHostedProviders: boolean;
}

export const DEFAULT_FETCH_PROVIDERS: FetchProviderId[] = ["http", "firecrawl", "jina", "tinyfish", "search1api", "querit", "kagi", "ollama", "parallel", "brightdata", "gemini"];

export function getFetchRouting(): FetchRouting {
	const root = getConfig();
	if (root.fetchRouting === undefined) return { providers: DEFAULT_FETCH_PROVIDERS, allowRemoteHostedProviders: false };
	if (!root.fetchRouting || typeof root.fetchRouting !== "object" || Array.isArray(root.fetchRouting)) throw new Error("fetchRouting must be an object");
	const config = root.fetchRouting as Record<string, unknown>;
	let providers = DEFAULT_FETCH_PROVIDERS;
	if (config.providers !== undefined) {
		if (!Array.isArray(config.providers) || config.providers.length === 0) throw new Error("fetchRouting.providers must be a non-empty array");
		providers = [];
		for (const value of config.providers) {
			const provider = typeof value === "string" ? value.trim().toLowerCase() : "";
			if (!FETCH_PROVIDER_IDS.includes(provider as FetchProviderId)) throw new Error(`fetchRouting.providers contains an invalid provider: ${String(value)}`);
			if (providers.includes(provider as FetchProviderId)) throw new Error(`fetchRouting.providers must not contain duplicates: ${provider}`);
			providers.push(provider as FetchProviderId);
		}
	}
	if (config.allowRemoteHostedProviders !== undefined && typeof config.allowRemoteHostedProviders !== "boolean") throw new Error("fetchRouting.allowRemoteHostedProviders must be a boolean");
	return { providers, allowRemoteHostedProviders: config.allowRemoteHostedProviders === true };
}