import type { ApiInfo, ApiData } from "../types";
import semiver from "semiver";
import { API_INFO_URL, BROKEN_CONNECTION_MSG } from "../constants";
import { Client } from "../client";
import { SPACE_FETCHER_URL } from "../constants";
import { join_urls, transform_api_info } from "../helpers/api_info";

export async function view_api(this: Client): Promise<any> {
	if (this.api_info) return this.api_info;

	const { hf_token } = this.options;
	const { config } = this;

	const headers: {
		Authorization?: string;
		"Content-Type": "application/json";
	} = { "Content-Type": "application/json" };

	if (hf_token) {
		headers.Authorization = `Bearer ${hf_token}`;
	}

	if (!config) {
		return;
	}

	try {
		let response: Response;

		if (semiver(config?.version || "2.0.0", "3.30") < 0) {
			response = await this.fetch(SPACE_FETCHER_URL, {
				method: "POST",
				body: JSON.stringify({
					serialize: false,
					config: JSON.stringify(config)
				}),
				headers,
				credentials: "include"
			});
		} else {
			const url = join_urls(config.root, API_INFO_URL);
			response = await this.fetch(url, {
				headers,
				credentials: "include"
			});
		}

		if (!response.ok) {
			throw new Error(BROKEN_CONNECTION_MSG);
		}

		let api_info = (await response.json()) as
			| ApiInfo<ApiData>
			| { api: ApiInfo<ApiData> };
		if ("api" in api_info) {
			api_info = api_info.api;
		}

		if (
			api_info.named_endpoints["/predict"] &&
			!api_info.unnamed_endpoints["0"]
		) {
			api_info.unnamed_endpoints[0] = api_info.named_endpoints["/predict"];
		}

		return transform_api_info(api_info, config, this.api_map);
	} catch (e) {
		"Could not get API info. " + (e as Error).message;
	}
}