bmstu-mt-wp/scripts/script.js

279 lines
6.3 KiB
JavaScript
Executable File

(function () {
var url = window.location,
body = document.body,
slides = document.querySelectorAll('div.slide'),
progress = document.querySelector('div.progress div'),
slideList = [],
l = slides.length, i;
for (i = 0; i < l; i++) {
slideList.push({
id: slides[i].id,
hasInnerNavigation: null !== slides[i].querySelector('.inner')
});
}
function getTransform() {
var denominator = Math.max(
body.clientWidth / window.innerWidth,
body.clientHeight / window.innerHeight
);
return 'scale(' + (1 / denominator) + ')';
}
function applyTransform(transform) {
body.style.WebkitTransform = transform;
body.style.MozTransform = transform;
body.style.msTransform = transform;
body.style.OTransform = transform;
body.style.transform = transform;
}
function enterSlideMode() {
body.className = 'full';
applyTransform(getTransform());
}
function enterListMode() {
body.className = 'list';
applyTransform('none');
}
function getCurrentSlideNumber() {
var i, l = slideList.length,
currentSlideId = url.hash.substr(1);
for (i = 0; i < l; ++i) {
if (currentSlideId === slideList[i].id) {
return i;
}
}
return -1;
}
function scrollToCurrentSlide() {
var currentSlide = document.getElementById(
slideList[getCurrentSlideNumber()].id
);
if (null != currentSlide) {
window.scrollTo(0, currentSlide.offsetTop);
}
}
function isListMode() {
return 'full' !== url.search.substr(1);
}
function normalizeSlideNumber(slideNumber) {
if (0 > slideNumber) {
return slideList.length - 1;
} else if (slideList.length <= slideNumber) {
return 0;
} else {
return slideNumber;
}
}
function updateProgress(slideNumber) {
if (null === progress) { return; }
progress.style.width = (100 / (slideList.length - 1) * normalizeSlideNumber(slideNumber)).toFixed(2) + '%';
}
function getSlideHash(slideNumber) {
return '#' + slideList[normalizeSlideNumber(slideNumber)].id;
}
function goToSlide(slideNumber) {
url.hash = getSlideHash(slideNumber);
if (!isListMode()) {
updateProgress(slideNumber);
}
}
function getContainingSlideId(el) {
var node = el;
while ('BODY' !== node.nodeName && 'HTML' !== node.nodeName) {
if (node.classList.contains('slide')) {
return node.id;
} else {
node = node.parentNode;
}
}
return '';
}
function dispatchSingleSlideMode(e) {
var slideId = getContainingSlideId(e.target);
if ('' !== slideId && isListMode()) {
e.preventDefault();
// NOTE: we should update hash to get things work properly
url.hash = '#' + slideId;
history.replaceState(null, null, url.pathname + '?full#' + slideId);
enterSlideMode();
updateProgress(getCurrentSlideNumber());
}
}
// Increases inner navigation by adding 'active' class to next inactive inner navigation item
function increaseInnerNavigation(slideNumber) {
// Shortcut for slides without inner navigation
if (true !== slideList[slideNumber].hasInnerNavigation) { return -1; }
var activeNodes = document.querySelectorAll(getSlideHash(slideNumber) + ' .active'),
// NOTE: we assume there is no other elements in inner navigation
node = activeNodes[activeNodes.length - 1].nextElementSibling;
if (null !== node) {
node.classList.add('active');
return activeNodes.length + 1;
} else {
return -1;
}
}
// Event handlers
window.addEventListener('DOMContentLoaded', function () {
if (!isListMode()) {
// "?full" is present without slide hash, so we should display first slide
if (-1 === getCurrentSlideNumber()) {
history.replaceState(null, null, url.pathname + '?full' + getSlideHash(0));
}
enterSlideMode();
updateProgress(getCurrentSlideNumber());
}
}, false);
window.addEventListener('popstate', function (e) {
if (isListMode()) {
enterListMode();
scrollToCurrentSlide();
} else {
enterSlideMode();
}
}, false);
window.addEventListener('resize', function (e) {
if (!isListMode()) {
applyTransform(getTransform());
}
}, false);
document.addEventListener('keydown', function (e) {
// Shortcut for alt, shift and meta keys
if (e.altKey || e.ctrlKey || e.metaKey) { return; }
var currentSlideNumber = getCurrentSlideNumber();
switch (e.which) {
case 116: // F5
case 13: // Enter
if (isListMode()) {
e.preventDefault();
history.pushState(null, null, url.pathname + '?full' + getSlideHash(currentSlideNumber));
enterSlideMode();
updateProgress(currentSlideNumber);
}
break;
case 27: // Esc
if (!isListMode()) {
e.preventDefault();
history.pushState(null, null, url.pathname + getSlideHash(currentSlideNumber));
enterListMode();
scrollToCurrentSlide();
}
break;
case 33: // PgUp
case 38: // Up
case 37: // Left
case 72: // h
case 75: // k
e.preventDefault();
currentSlideNumber--;
goToSlide(currentSlideNumber);
break;
case 34: // PgDown
case 40: // Down
case 39: // Right
case 76: // l
case 74: // j
e.preventDefault();
// Only go to next slide if current slide have no inner
// navigation or inner navigation is fully shown
if (
!slideList[currentSlideNumber].hasInnerNavigation ||
-1 === increaseInnerNavigation(currentSlideNumber)
) {
currentSlideNumber++;
goToSlide(currentSlideNumber);
}
break;
case 36: // Home
e.preventDefault();
currentSlideNumber = 0;
goToSlide(currentSlideNumber);
break;
case 35: // End
e.preventDefault();
currentSlideNumber = slideList.length - 1;
goToSlide(currentSlideNumber);
break;
case 9: // Tab = +1; Shift + Tab = -1
case 32: // Space = +1; Shift + Space = -1
e.preventDefault();
currentSlideNumber += e.shiftKey ? -1 : 1;
goToSlide(currentSlideNumber);
break;
default:
// Behave as usual
}
}, false);
document.addEventListener('click', dispatchSingleSlideMode, false);
document.addEventListener('touchend', dispatchSingleSlideMode, false);
document.addEventListener('touchstart', function (e) {
if (!isListMode()) {
var currentSlideNumber = getCurrentSlideNumber(),
x = e.touches[0].pageX;
if (x > window.innerWidth / 2) {
currentSlideNumber++;
} else {
currentSlideNumber--;
}
goToSlide(currentSlideNumber);
}
}, false);
document.addEventListener('touchmove', function (e) {
if (!isListMode()) {
e.preventDefault();
}
}, false);
}());