docsify/lib/plugins/zoom-image.js
2017-03-09 20:30:38 +08:00

305 lines
8.4 KiB
JavaScript

this.D = this.D || {};
(function () {
'use strict';
var commonjsGlobal = typeof window !== 'undefined' ? window : typeof global !== 'undefined' ? global : typeof self !== 'undefined' ? self : {};
function createCommonjsModule(fn, module) {
return module = { exports: {} }, fn(module, module.exports), module.exports;
}
var zoomImage = createCommonjsModule(function (module, exports) {
(function (global, factory) {
module.exports = factory();
}(commonjsGlobal, (function () { 'use strict';
var windowWidth = function () { return document.documentElement.clientWidth; };
var windowHeight = function () { return document.documentElement.clientHeight; };
var elemOffset = function (elem) {
var rect = elem.getBoundingClientRect();
var docElem = document.documentElement;
var win = window;
return {
top: rect.top + win.pageYOffset - docElem.clientTop,
left: rect.left + win.pageXOffset - docElem.clientLeft
}
};
var once = function (elem, type, handler) {
var fn = function (e) {
e.target.removeEventListener(type, fn);
handler();
};
elem.addEventListener(type, fn);
};
var Size = function Size(w, h) {
this.w = w;
this.h = h;
};
var ZoomImage = function ZoomImage(img, offset) {
this.img = img;
this.preservedTransform = img.style.transform;
this.wrap = null;
this.overlay = null;
this.offset = offset;
};
ZoomImage.prototype.forceRepaint = function forceRepaint () {
var _ = this.img.offsetWidth;
return
};
ZoomImage.prototype.zoom = function zoom () {
var size = new Size(this.img.naturalWidth, this.img.naturalHeight);
this.wrap = document.createElement('div');
this.wrap.classList.add('zoom-img-wrap');
this.img.parentNode.insertBefore(this.wrap, this.img);
this.wrap.appendChild(this.img);
this.img.classList.add('zoom-img');
this.img.setAttribute('data-action', 'zoom-out');
this.overlay = document.createElement('div');
this.overlay.classList.add('zoom-overlay');
document.body.appendChild(this.overlay);
this.forceRepaint();
var scale = this.calculateScale(size);
this.forceRepaint();
this.animate(scale);
document.body.classList.add('zoom-overlay-open');
};
ZoomImage.prototype.calculateScale = function calculateScale (size) {
var maxScaleFactor = size.w / this.img.width;
var viewportWidth = (windowWidth() - this.offset);
var viewportHeight = (windowHeight() - this.offset);
var imageAspectRatio = size.w / size.h;
var viewportAspectRatio = viewportWidth / viewportHeight;
if (size.w < viewportWidth && size.h < viewportHeight) {
return maxScaleFactor
} else if (imageAspectRatio < viewportAspectRatio) {
return (viewportHeight / size.h) * maxScaleFactor
}
return (viewportWidth / size.w) * maxScaleFactor
};
ZoomImage.prototype.animate = function animate (scale) {
var imageOffset = elemOffset(this.img);
var scrollTop = window.pageYOffset;
var viewportX = (windowWidth() / 2);
var viewportY = scrollTop + (windowHeight() / 2);
var imageCenterX = imageOffset.left + (this.img.width / 2);
var imageCenterY = imageOffset.top + (this.img.height / 2);
var tx = viewportX - imageCenterX;
var ty = viewportY - imageCenterY;
var tz = 0;
var imgTr = "scale(" + scale + ")";
var wrapTr = "translate3d(" + tx + "px, " + ty + "px, " + tz + "px)";
this.img.style.transform = imgTr;
this.wrap.style.transform = wrapTr;
};
ZoomImage.prototype.dispose = function dispose () {
if (this.wrap === null || this.wrap.parentNode === null) {
return
}
this.img.classList.remove('zoom-img');
this.img.setAttribute('data-action', 'zoom');
this.wrap.parentNode.insertBefore(this.img, this.wrap);
this.wrap.parentNode.removeChild(this.wrap);
document.body.removeChild(this.overlay);
document.body.classList.remove('zoom-overlay-transitioning');
};
ZoomImage.prototype.close = function close () {
var this$1 = this;
document.body.classList.add('zoom-overlay-transitioning');
this.img.style.transform = this.preservedTransform;
if (this.img.style.length === 0) {
this.img.removeAttribute('style');
}
this.wrap.style.transform = 'none';
once(this.img, 'transitionend', function () {
this$1.dispose();
// remove class should happen after dispose. Otherwise,
// a new click event could fire and create a duplicate ZoomImage for
// the same <img> element.
document.body.classList.remove('zoom-overlay-open');
});
};
/**
* Pure JavaScript implementation of zoom.js.
*
* Original preamble:
* zoom.js - It's the best way to zoom an image
* @version v0.0.2
* @link https://github.com/fat/zoom.js
* @license MIT
*
* Needs a related CSS file to work. See the README at
* https://github.com/nishanths/zoom.js for more info.
*
* This is a fork of the original zoom.js implementation by @fat.
* Copyrights for the original project are held by @fat. All other copyright
* for changes in the fork are held by Nishanth Shanmugham.
*
* Copyright (c) 2013 @fat
* The MIT License. Copyright © 2016 Nishanth Shanmugham.
*/
var current = null;
var offset = 80;
var initialScrollPos = -1;
var initialTouchPos = -1;
function handleScroll() {
if (initialScrollPos === -1) {
initialScrollPos = window.pageYOffset;
}
var deltaY = Math.abs(initialScrollPos - window.pageYOffset);
if (deltaY >= 40) {
closeCurrent();
}
}
function handleKeyup(e) {
if (e.keyCode === 27) {
closeCurrent();
}
}
function handleTouchStart(e) {
var t = e.touches[0];
if (t === null) {
return
}
initialTouchPos = t.pageY;
e.target.addEventListener('touchmove', handleTouchMove);
}
function handleTouchMove(e) {
var t = e.touches[0];
if (t === null) {
return
}
if (Math.abs(t.pageY - initialTouchPos) > 10) {
closeCurrent();
e.target.removeEventListener('touchmove', handleTouchMove);
}
}
function handleClick() {
closeCurrent();
}
function addCloseListeners() {
document.addEventListener('scroll', handleScroll);
document.addEventListener('keyup', handleKeyup);
document.addEventListener('touchstart', handleTouchStart);
document.addEventListener('click', handleClick, true);
}
function removeCloseListeners() {
document.removeEventListener('scroll', handleScroll);
document.removeEventListener('keyup', handleKeyup);
document.removeEventListener('touchstart', handleTouchStart);
document.removeEventListener('click', handleClick, true);
}
function closeCurrent(force) {
if (current === null) {
return
}
if (force) {
current.dispose();
} else {
current.close();
}
removeCloseListeners();
current = null;
}
function prepareZoom(e) {
if (document.body.classList.contains('zoom-overlay-open')) {
return
}
if (e.metaKey || e.ctrlKey) {
window.open((e.target.getAttribute('data-original') || e.target.src), '_blank');
return
}
if (e.target.width >= windowWidth() - offset) {
return
}
closeCurrent(true);
current = new ZoomImage(e.target, offset);
current.zoom();
addCloseListeners();
}
var zoom = function (el) {
el.setAttribute('data-action', 'zoom');
el.addEventListener('click', prepareZoom);
return function () { return el.removeEventListener('click', prepareZoom); }
};
return zoom;
})));
});
var style = "img[data-action=\"zoom\"] {\n cursor: pointer;\n cursor: -webkit-zoom-in;\n cursor: zoom-in;\n}\n.zoom-img,\n.zoom-img-wrap {\n position: relative;\n z-index: 666;\n transition: -webkit-transform 300ms cubic-bezier(.2,0,.2,1);\n transition: transform 300ms cubic-bezier(.2,0,.2,1);\n transition: transform 300ms cubic-bezier(.2,0,.2,1), -webkit-transform 300ms cubic-bezier(.2,0,.2,1);\n}\n.zoom-overlay {\n z-index: 420;\n background: #fff;\n position: fixed;\n top: 0;\n left: 0;\n right: 0;\n bottom: 0;\n pointer-events: none;\n opacity: 0;\n transition: opacity 300ms;\n}\n.zoom-overlay-open .zoom-overlay {\n opacity: 1;\n}\n.zoom-overlay-open {\n cursor: pointer;\n cursor: -webkit-zoom-out;\n cursor: zoom-out;\n}\n.zoom-overlay-transitioning {\n cursor: default;\n}\n.zoom-overlay-open.zoom-overlay-transitioning .zoom-overlay{\n opacity: 0;\n}\n";
function install (hook) {
var dom = Docsify.dom;
var destroys;
// add style
dom.appendTo(dom.head, dom.create('style', style));
hook.doneEach(function (_) {
var images = dom.findAll('img:not(.emoji)');
if (Array.isArray(destroys) && destroys.length) {
destroys.forEach(function (o) { return o(); });
destroys = [];
}
destroys = images.map(zoomImage);
});
}
$docsify.plugins = [].concat(install, $docsify.plugins);
}());