import {AnyJson} from "~/types/types";

/**
 * @category Services/utils
 * @class HydraParser
 * Classe permettant d'assurer le parsing d'une réponse Hydra
 */
class HydraParser {
  /**
   * Parcours une réponse Hydra pour retourner son équivalent en Json
   * @param {AnyJson} hydraData
   * @return {AnyJson} réponse parsée
   */
  parse(hydraData: AnyJson): AnyJson {
    if (hydraData['hydra:member']) {
      hydraData.totalCount = hydraData['hydra:totalItems'];
      return this.parseCollection(hydraData);
    } else {
      return this.parseItem(hydraData);
    }
  }

  /**
   * Méthode de parsing appelé si on est dans un GET
   * @param {AnyJson} hydraData
   */
  parseItem(hydraData: AnyJson): AnyJson {
    this.populateId(hydraData);

    if (hydraData['hydra:previous']) {
      let iriParts = hydraData['hydra:previous'].split('/');
      hydraData.previous = iriParts[iriParts.length - 1];
    }
    if (hydraData['hydra:next']) {
      let iriParts = hydraData['hydra:next'].split('/');
      hydraData.next = iriParts[iriParts.length - 1];
    }
    if (hydraData['hydra:totalItems']) {
      hydraData.totalItems = hydraData['hydra:totalItems'];
    }
    if (hydraData['hydra:itemPosition']) {
      hydraData.itemPosition = hydraData['hydra:itemPosition'];
    }
    return hydraData;
  }

  /**
   * Méthode de parsing appelé si on est dans un GET Collection
   * @param {AnyJson} hydraData
   */
  parseCollection(hydraData: AnyJson): AnyJson {
    let collectionResponse = hydraData['hydra:member'];
    collectionResponse.metadata = {};
    collectionResponse.order = {};
    collectionResponse.search = {};

    // Put metadata in a property of the collection
    for (const key in hydraData) {
      const value = hydraData[key];
      if ('hydra:member' !== key) {
        collectionResponse.metadata[key] = value;
      }
    }

    // Populate href property for all elements of the collection
    for (const key in collectionResponse) {
      const value = collectionResponse[key];
      this.populateAllData(value);
    }

    if ('undefined' !== typeof (hydraData['hydra:search'])) {
      let collectionSearch = hydraData['hydra:search']['hydra:mapping'];
      for (const key in collectionSearch) {
        const value = collectionSearch[key];
        if (value['variable'].indexOf("filter[order]") === 0) {
          collectionResponse.order[value['property']] = value;
        } else if (value['variable'].indexOf("filter[where]") === 0) {
          collectionResponse.search[value['property']] = value;
        }
      }
    }
    return collectionResponse;
  }


  /**
   * Hydrate l'objet Json avec la valeur id correspondant à l'uri de l'objet
   * @param {AnyJson} data
   */
  populateId(data: AnyJson): void{
    if (data['@id'] && data['@id'] instanceof String) {
      var iriParts = data['@id'].split('/');
      data.id = iriParts[iriParts.length - 1];
    }
  }

  /**
   * Hydrate l'objet JSON de façon récursive (afin de gérer les objet nested)
   * @param {AnyJson} data
   */
  populateAllData(data: AnyJson):void {
    this.populateId(data);
    for (const key in data) {
      const value = data[key];
      if (value instanceof Object) {
        this.populateAllData(value);
      }
    }
  }
}

export const $hydraParser = new HydraParser()