/**

* Write loading image to a container for ajax request

*

* @param container: a jQuery object

*/

function showLoadingImage(container) {

container.empty().append('<div class="barspinner dark"><div class="rect1"></div><div class="rect2"></div><div class="rect3"></div><div class="rect4"></div><div class="rect5"></div></div>');

}

/**

* Returns the highest z-index in the page.

* Accepts a jquery style selector to only check those elements,

* uses all container tags by default

* If no element found, returns null.

*

* @param selector: a jquery style selector for target elements

* @return int|null

*/

function get_highest_zindex(selector) {

if (!selector) {

selector = 'div,p,area,nav,section,header,canvas,aside,span';

}

const all = [];

const _store_zindex = function () {

if ($(this).is(':visible')) {

const z = $(this).css('z-index');

if (!isNaN(z)) {

all.push(z);

}

}

};

$(selector).each(_store_zindex);

return all.length ? Math.max(...all) : null;

}

function downloadCSV(csvContents, filename) {

filename = filename || 'data.csv';

if (navigator.msSaveBlob) { // IE 10+

navigator.msSaveBlob(new Blob([csvContents], { type: 'text/csv;charset=utf-8;' }), filename);

} else { // Other browsers

const csv = 'data:text/csv;charset=utf-8,' + csvContents;

const downloadLink = document.createElement('a');

downloadLink.href = encodeURI(csv);

downloadLink.download = filename;

document.body.appendChild(downloadLink);

downloadLink.click();

document.body.removeChild(downloadLink);

}

}

function template(string, content) {

return string.replace(/\[_(\d+)\]/g, function(s, index) {

return content[(+index) - 1];

});

}

function objectNotEmpty(obj) {

let isEmpty = true;

if (obj && obj instanceof Object) {

Object.keys(obj).forEach(function(key) {

if (obj.hasOwnProperty(key)) isEmpty = false;

});

}

return !isEmpty;

}

module.exports = {

showLoadingImage : showLoadingImage,

get_highest_zindex: get_highest_zindex,

downloadCSV : downloadCSV,

template : template,

objectNotEmpty : objectNotEmpty,

};