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/auth/status';
export const API_INIT = '/api/v1/auth/init';
export const API_LOGIN = '/api/v1/auth/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
	}
}