export const REQUEST_TYPE_POST = "POST";
export const REQUEST_TYPE_GET = "GET";
export const REQUEST_TYPE_PUT = "PUT";
export const REQUEST_TYPE_DELETE = "DELETE";
export const CONTENT_TYPE_JSON = "json";
export const CONTENT_TYPE_FORM = "x-www-form-urlencoded";
export const API_STATUS = "/api/v1/status";
export const API_INIT = "/api/v1/init";
export const API_LOGIN = "/api/v1/login";
export const API_GET_PAGES = "/api/v1/page/published";
export const API_GET_PAGE = "/api/v1/page/single";
import * as DataEvent from "../com/events/DataEvent";
export default class APIUtils {
  //--------------------------
  // constructor
  //--------------------------
  constructor() {}
  //--------------------------
  // public
  //--------------------------
  login(data) {
    return new Promise((resolve, reject) => {
      this._request(
        API_LOGIN,
        DataEvent.AUTH_STATUS,
        REQUEST_TYPE_POST,
        CONTENT_TYPE_JSON,
        data
      )
        .then((result) => {
          resolve(result);
        })
        .catch((err) => {
          reject(err);
        });
    });
  }
  init(data) {
    return new Promise((resolve, reject) => {
      this._request(
        API_INIT,
        DataEvent.API_INIT,
        REQUEST_TYPE_POST,
        CONTENT_TYPE_JSON,
        data
      )
        .then((result) => {
          resolve(result);
        })
        .catch((err) => {
          reject(err);
        });
    });
  }
  getPages(num) {
    let pageNum = num;
    if (pageNum === null || pageNum === "" || !pageNum) pageNum = 1;
    return new Promise((resolve, reject) => {
      this._request(
        API_GET_PAGES + "/" + pageNum,
        DataEvent.API_GET_PAGES,
        REQUEST_TYPE_GET
      )
        .then((result) => {
          resolve(result);
        })
        .catch((err) => {
          reject(err);
        });
    });
  }

  getPage(id) {
    return new Promise((resolve, reject) => {
      this._request(
        API_GET_PAGE + "/" + id,
        DataEvent.API_GET_PAGES,
        REQUEST_TYPE_GET
      )
        .then((result) => {
          resolve(result);
        })
        .catch((err) => {
          reject(err);
        });
    });
  }
  //--------------------------
  // private
  //--------------------------
  _request(
    requestURL,
    eventType,
    requestType = REQUEST_TYPE_GET,
    contentType = CONTENT_TYPE_JSON,
    requestData = null
  ) {
    var self = this;
    return new Promise(function (resolve, reject) {
      var request = new XMLHttpRequest();
      request.upload.onprogress = self.handleLoadProgress;
      request.open(requestType, requestURL, true);
      request.onload = () => {
        if (request.status == 200) {
          let response = JSON.parse(request["response"]);
          resolve(response);
        } else {
          let error = JSON.parse(request["response"]);
          reject(error);
        }
      };
      if (requestType == REQUEST_TYPE_PUT || requestType == REQUEST_TYPE_POST) {
        switch (contentType) {
          case CONTENT_TYPE_JSON:
            request.setRequestHeader(
              "Content-type",
              "application/" + contentType
            );
            request.send(JSON.stringify(requestData));
            break;
          case CONTENT_TYPE_FORM:
            request.send(requestData);
            break;
        }
      } else {
        request.send();
      }
    });
  }

  //--------------------------
  // event handlers
  //--------------------------
  handleLoadProgress(e) {
    this.percentComplete = Math.ceil((e.loaded / e.total) * 100);
    //pass element to display request progress
  }
}