import * as radius from 'radius';
import * as gblConfig from '../config';
import { IPacket } from './types/PacketHandler';
import { Authentication } from './auth';
import { UDPServer } from './server/UDPServer';
import { RadiusService } from './radius/RadiusService';

export type PacketDecoder = (msg: Buffer) =>
	| {
			packet?: radius.RadiusPacket & IPacket;
			secret: string;
	  }
	| Promise<{
			packet?: radius.RadiusPacket & IPacket;
			secret: string;
	  }>;

export default class PackageInterface {
	private static _instance?: PackageInterface;

	public static get(): PackageInterface {
		if (!this._instance) {
			this._instance = new PackageInterface();
		}

		return this._instance;
	}

	public packetDecoder?: PacketDecoder;

	public start = true;

	public cacheTTL = 60000;

	public cacheSuccessTTL = 86400;

	public cacheFailTTL = 60;

	public logger: (...any: unknown[]) => unknown = console.log; // eslint-disable-line no-console

	private config: any = gblConfig;

	private server?: UDPServer;

	public log(...any: unknown[]): void {
		this.logger(...any);
	}

	public getConfig(): any {
		return this.config;
	}

	// eslint-disable-next-line @typescript-eslint/explicit-module-boundary-types
	public setConfig(inConfig: any) {
		this.config = inConfig;
	}

	public async up(): Promise<void> {
		const config = this.getConfig();
		const AuthMechanismus = (await import(`./auth/${config.authentication}`))[
			config.authentication
		];

		const auth = new AuthMechanismus(config.authenticationOptions);
		const authentication = new Authentication(auth);
		this.server = new UDPServer(config.port);
		const radiusService = new RadiusService(config.secret, authentication);

		this.server.on('message', async (msg, rinfo) => {
			const response = await radiusService.handleMessage(msg);

			if (response && this.server) {
				this.server.sendToClient(
					response.data,
					rinfo.port,
					rinfo.address,
					(err, _bytes) => {
						if (err) {
							this.log('Error sending response to ', rinfo);
						}
					},
					response.expectAcknowledgment
				);
			}
		});

		await this.server.start();
	}

	public isUp(): boolean {
		return !!this.server;
	}

	public async down(): Promise<void> {
		if (this.server) {
			await this.server.stop();
			this.server = undefined;
		}
	}
}