import { Context } from '@nuxt/types/app'
import { AnyJson, DataProviderArgs } from '~/types/interfaces'
import { DENORMALIZER_TYPE, HTTP_METHOD, QUERY_TYPE } from '~/types/enums'
import { providers } from '~/services/dataProvider/provider/_import'
import ConstructUrl from '~/services/connection/constructUrl'
import Connection from '~/services/connection/connection'
import Serializer from '~/services/serializer/serializer'
import ApiError from '~/services/utils/apiError'

/**
 * Le DataProvider a pour rôle de fournir des données issues de l'API Opentalent
 */
class DataProvider {
  private ctx !: Context;
  private readonly defaultArguments!: DataProviderArgs;

  constructor () {
    this.defaultArguments = {
      type: QUERY_TYPE.MODEL,
      progress: false
    }
  }

  /**
   * Initialise le contexte (la connection en particulier)
   * @param ctx
   */
  public initCtx (ctx: Context) {
    Connection.initConnector(ctx.$axios)
    this.ctx = ctx
  }

  /**
   * Exécute la requête et retourne la réponse désérialisée
   * @param args
   */
  public async invoke (args: DataProviderArgs): Promise<any> {
    try {
      // complete args with defaults
      args = { ...this.defaultArguments, ...args }

      DataProvider.startLoading(args)

      const url = ConstructUrl.invoke(args)

      const response = await DataProvider.sendRequest(url, args)

      const deserializeResponse = await Serializer.denormalize(response, DENORMALIZER_TYPE.HYDRA)

      return await this.provide(deserializeResponse, args)
    } catch (error) {
      throw new ApiError(500, error)
    }
  }

  /**
   * Signale le début du chargement à nuxt (si progress est true)
   * @param args
   */
  private static startLoading (args: DataProviderArgs) {
    if (args.progress) {
      const $nuxt = window.$nuxt
      $nuxt.$loading.start()
    }
  }

  /**
   * Send the request trough the Connection
   * @param url
   * @param args
   */
  public static sendRequest (url: string, args: DataProviderArgs): Promise<any> {
    return Connection.invoke(HTTP_METHOD.GET, url, args)
  }

  /**
   * Iterate over the available providers and invoke
   * the first one that support the given args
   * @param data
   * @param args
   */
  public provide (data: AnyJson, args: DataProviderArgs): any {
    for (const Provider of providers) {
      if (Provider.support(args)) {
        return new Provider(this.ctx, args).invoke(data)
      }
    }
  }
}

export default DataProvider