import { inject } from '@loopback/context'
import {
  FindRoute,
  InvokeMethod,
  ParseParams,
  Reject,
  RequestContext,
  RestBindings,
  Send,
  SequenceHandler
} from '@loopback/rest'

const SequenceActions = RestBindings.SequenceActions

export class MySequence implements SequenceHandler {
  constructor(
    @inject(SequenceActions.FIND_ROUTE) protected findRoute: FindRoute,
    @inject(SequenceActions.PARSE_PARAMS) protected parseParams: ParseParams,
    @inject(SequenceActions.INVOKE_METHOD) protected invoke: InvokeMethod,
    @inject(SequenceActions.SEND) public send: Send,
    @inject(SequenceActions.REJECT) public reject: Reject
  ) {}

  async handle(context: RequestContext) {
    try {
      const { request, response } = context
      const route = this.findRoute(request)
      const args = await this.parseParams(request, route)
      const result = await this.invoke(route, args)
      this.send(response, result)
    } catch (err) {
      this.reject(context, err)
    }
  }
}