var addSorting = (function () {
"use strict";
var cols,
currentSort = {
index: 0,
desc: false
};
// returns the summary table element
function getTable() { return document.querySelector('.coverage-summary'); }
// returns the thead element of the summary table
function getTableHeader() { return getTable().querySelector('thead tr'); }
// returns the tbody element of the summary table
function getTableBody() { return getTable().querySelector('tbody'); }
// returns the th element for nth column
function getNthColumn(n) { return getTableHeader().querySelectorAll('th')[n]; }
// loads all columns
function loadColumns() {
var colNodes = getTableHeader().querySelectorAll('th'),
colNode,
cols = [],
col,
i;
for (i = 0; i < colNodes.length; i += 1) {
colNode = colNodes[i];
col = {
key: colNode.getAttribute('data-col'),
sortable: !colNode.getAttribute('data-nosort'),
type: colNode.getAttribute('data-type') || 'string'
};
cols.push(col);
if (col.sortable) {
col.defaultDescSort = col.type === 'number';
colNode.innerHTML = colNode.innerHTML + '<span class="sorter"></span>';
}
}
return cols;
}
// attaches a data attribute to every tr element with an object
// of data values keyed by column name
function loadRowData(tableRow) {
var tableCols = tableRow.querySelectorAll('td'),
colNode,
col,
data = {},
i,
val;
for (i = 0; i < tableCols.length; i += 1) {
colNode = tableCols[i];
col = cols[i];
val = colNode.getAttribute('data-value');
if (col.type === 'number') {
val = Number(val);
}
data[col.key] = val;
}
return data;
}
// loads all row data
function loadData() {
var rows = getTableBody().querySelectorAll('tr'),
i;
for (i = 0; i < rows.length; i += 1) {
rows[i].data = loadRowData(rows[i]);
}
}
// sorts the table using the data for the ith column
function sortByIndex(index, desc) {
var key = cols[index].key,
sorter = function (a, b) {
a = a.data[key];
b = b.data[key];
return a < b ? -1 : a > b ? 1 : 0;
},
finalSorter = sorter,
tableBody = document.querySelector('.coverage-summary tbody'),
rowNodes = tableBody.querySelectorAll('tr'),
rows = [],
i;
if (desc) {
finalSorter = function (a, b) {
return -1 * sorter(a, b);
};
}
for (i = 0; i < rowNodes.length; i += 1) {
rows.push(rowNodes[i]);
tableBody.removeChild(rowNodes[i]);
}
rows.sort(finalSorter);
for (i = 0; i < rows.length; i += 1) {
tableBody.appendChild(rows[i]);
}
}
// removes sort indicators for current column being sorted
function removeSortIndicators() {
var col = getNthColumn(currentSort.index),
cls = col.className;
cls = cls.replace(/ sorted$/, '').replace(/ sorted-desc$/, '');
col.className = cls;
}
// adds sort indicators for current column being sorted
function addSortIndicators() {
getNthColumn(currentSort.index).className += currentSort.desc ? ' sorted-desc' : ' sorted';
}
// adds event listeners for all sorter widgets
function enableUI() {
var i,
el,
ithSorter = function ithSorter(i) {
var col = cols[i];
return function () {
var desc = col.defaultDescSort;
if (currentSort.index === i) {
desc = !currentSort.desc;
}
sortByIndex(i, desc);
removeSortIndicators();
currentSort.index = i;
currentSort.desc = desc;
addSortIndicators();
};
};
for (i =0 ; i < cols.length; i += 1) {
if (cols[i].sortable) {
// add the click event handler on the th so users
// dont have to click on those tiny arrows
el = getNthColumn(i).querySelector('.sorter').parentElement;
if (el.addEventListener) {
el.addEventListener('click', ithSorter(i));
} else {
el.attachEvent('onclick', ithSorter(i));
}
}
}
}
// adds sorting functionality to the UI
return function () {
if (!getTable()) {
return;
}
cols = loadColumns();
loadData(cols);
addSortIndicators();
enableUI();
};
})();
window.addEventListener('load', addSorting);