import { ConfigurableModuleBuilder, Module } from '@nestjs/common';
import type { NatsConnection } from 'nats';
import { type ClientConnection, type ClientMiddleware, type ServerRequest, ServiceClientModule } from '../../service';
import { SERVICE_CLIENT_MODULE_OPTIONS } from '../../service/client/ServiceClientModule';
import { NATS_CONNECTION, NatsModule } from '../NatsModule';
import { createNatsClientConnection } from './createNatsClientConnection';

export interface NatsServiceClientModuleOptions {
	getSubject?: (req: ServerRequest) => string;
	middlewares?: ClientMiddleware[];
}

const { ConfigurableModuleClass, MODULE_OPTIONS_TOKEN } =
	new ConfigurableModuleBuilder<NatsServiceClientModuleOptions>()
		.setExtras({ isGlobal: true }, (definition, extras) => ({ ...definition, global: extras.isGlobal }))
		.setClassMethodName('forRoot')
		.build();

const NATS_SERVICE_CLIENT_CONNECTION = Symbol('NATS_SERVICE_CLIENT_CONNECTION');

@Module({
	imports: [NatsModule, ServiceClientModule],
	providers: [
		{
			provide: NATS_SERVICE_CLIENT_CONNECTION,
			useFactory(nc: NatsConnection, { getSubject }: NatsServiceClientModuleOptions = {}) {
				return createNatsClientConnection({ nc, getSubject });
			},
			inject: [NATS_CONNECTION, { token: MODULE_OPTIONS_TOKEN, optional: true }],
		},
		{
			provide: SERVICE_CLIENT_MODULE_OPTIONS,
			useFactory(conn: ClientConnection, { middlewares = [] }: NatsServiceClientModuleOptions = {}) {
				return { connection: conn, middlewares };
			},
			inject: [NATS_SERVICE_CLIENT_CONNECTION, { token: MODULE_OPTIONS_TOKEN, optional: true }],
		},
	],
	exports: [ServiceClientModule, SERVICE_CLIENT_MODULE_OPTIONS],
})
export class NatsServiceClientModule extends ConfigurableModuleClass {}