import { Module, Type } from '@nestjs/common';
import { NestjsOemcService, OemcController } from './nestjs-oemc.service';
import { NestjsOemcExecuteService } from './nestjs-oemc-execute.service';
import { NestjsOemcController } from './nestjs-oemc.controller';
import { DiscoveryModule, DiscoveryService } from '@nestjs/core';
import { OEMC_CONTROLLER } from './nestjs-oemc.constants';

type ControllerType = any;

function getOemcControllerName(controllerType: ControllerType): string | null {
  if (Reflect.getMetadata(OEMC_CONTROLLER, controllerType)) {
    return Reflect.getMetadata(OEMC_CONTROLLER, controllerType);
  }
  return null;
}

function isOemcController(controllerType: ControllerType): boolean {
  if (getOemcControllerName(controllerType) !== null) {
    return true;
  }
  return false;
}

@Module({
  imports: [DiscoveryModule],
  providers: [NestjsOemcService, NestjsOemcExecuteService],
  controllers: [NestjsOemcController],
  exports: [NestjsOemcService, NestjsOemcExecuteService],
})
export class NestjsOemcModule {
  constructor(
    private readonly discoveryService: DiscoveryService,
    private readonly nestjsOemcService: NestjsOemcService,
  ) {}

  onModuleInit(): any {
    const wrappers = this.discoveryService.getControllers();

    const oemcControllerMaps: OemcController[] = wrappers
      .filter((wrapper) => wrapper.metatype && isOemcController(wrapper.metatype))
      .map((wrapper) => {
        return {
          controllerAlias: getOemcControllerName(wrapper.metatype),
          oemcController: wrapper.instance,
        };
      });

    oemcControllerMaps.forEach((provider) => this.nestjsOemcService.registerOemcController(provider));
  }
}