let haveRegistered = false;
import { Workflow, Domain } from 'simple-swf/build/src/entities';
import { ActivityWorker, DeciderWorker } from './workers';
import { Config } from './Config';

export interface InitedEntities {
  domain: Domain;
  workflow: Workflow;
  activityWorker: ActivityWorker;
  deciderWorker: DeciderWorker;
  config: Config;
}

let registration = {
  registerDomain(config: Config, cb: {(Error?, Domain?)}) {
    config.domain.ensureDomain(config.getConfigFor('swf.domain'), (err, created) => {
      if (err) { return cb(err); }

      config.logger.info(`domain  ${config.domain.name} ${created ? 'was created' : 'already exists'}`);
      cb(null, config.domain);
    });
  },

  registerWorkflowType(config: Config, domain: Domain, cb: {(Error?, Workflow?)}) {
    let workflow = new Workflow(domain, config.workflowName, config.defaultVersion, config.fieldSerializer);
    workflow.ensureWorkflow(config.getConfigFor('swf.workflow'), (err, created) => {
      if (err) { return cb(err); }

      config.logger.info(`workflow ${workflow.name} ${created ? 'was created' : 'already exists'}`);
      cb(null, workflow);
    });
  },

  init(config: Config, cb: {(err: Error | null, entities?: InitedEntities)}) {
    if (haveRegistered) { return cb(null); }

    registration.registerDomain(config, (err, domain) => {
      if (err) { return cb(err); }

      registration.registerWorkflowType(config, domain, (err, workflow) => {
        if (err) { return cb(err); }

        haveRegistered = true;
        const activityWorker = registration.initActivityWorker(config, workflow);
        const deciderWorker = registration.initDeciderWorker(config, workflow);

        cb(null, {workflow, domain, activityWorker, deciderWorker, config});
      });
    });
  },

  initActivityWorker(config: Config, workflow: Workflow) {
    let worker = new ActivityWorker(workflow, config, config.getConfigFor('swf.activityWorker'));
    config.activities.getModules().map((actType) => worker.registerActivityType(actType));

    return worker;
  },

  initDeciderWorker(config: Config, workflow: Workflow) {
    let TaskGraph = config.deciders.getModule('taskGraph');
    if (!TaskGraph) {
      throw new Error('missing taskGraph plugin!');
    }
    let taskGraphDecider = new TaskGraph(config, workflow);
    return new DeciderWorker(taskGraphDecider, config, config.getConfigFor('swf.deciderWorker'));
  }
};

export { registration }