TaoLer/public/static/component/pear/module/watermark/watermark.js

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2023-03-16 22:40:15 +08:00
/* global Watermark */
layui.define(['jquery', 'element'], function(exports) {
var $=layui.$;
var _parentEle;
var _wmContainer;
var _wmObserver;
var _wmParentObserver;
var _resizeHandler;
var _windowsWidth = window.outerWidth;
var _windowsHeight = window.outerHeight;
var _left = 0;
var _top = 0;
/**
* Create DOM of watermark's container
* @param {Watermark} watermark
*/
var _createContainer = function (watermark) {
watermark._container = document.createElement('div');
watermark._container.classList.add('cell-watermark-container');
watermark._container.style.cssText = 'display: block; pointer-events: none;';
watermark._container.setAttribute('aria-hidden', true);
_parentEle = document.querySelector(watermark.options.appendTo) || document.body;
//获取页面最大宽度
_windowsWidth = Math.min(_parentEle.scrollWidth, _parentEle.clientWidth);
//获取页面最大高度
_windowsHeight = Math.min(_parentEle.scrollHeight, _parentEle.clientHeight);
_parentEle.appendChild(watermark._container);
};
/**
* Create watermark's DOM
* @param {Watermark} watermark
* @param {Object} options
*/
var _createWatermark = function (watermark, options) {
options.rowSpacing = options.rowSpacing || 60;
options.colSpacing = options.colSpacing || 30;
options.width = options.width || 150;
options.height = options.height || 20;
let rows = parseInt(_windowsHeight / (options.height + options.rowSpacing));
let cols = parseInt(_windowsWidth / (options.width + options.colSpacing));
let offsetLeft =_left+ (_windowsWidth - options.width * cols - options.colSpacing * (cols - 1)) / 2;
let offsetTop = _top+(_windowsHeight - options.height * rows - options.rowSpacing * (rows - 1)) / 2;
let watermarkBase = document.createElement('div');
watermarkBase.classList.add('cell-watermark');
watermarkBase.style.cssText =
'transform: rotate(15deg); opacity: 0.1; font-size: 0.85rem; text-align: center;' +
'position: absolute; user-select: none; word-break: break-all; overflow: hidden; z-index: 999999;';
for (let row = 0; row < rows; row++) {
let top = offsetTop + (options.rowSpacing + options.height) * row;
let tempCols = cols;
row % 2 !== 0 && tempCols++;
for (let col = 0; col < tempCols; col++) {
let left = offsetLeft + (options.colSpacing + options.width) * col;
tempCols !== cols && (left -= (options.colSpacing + options.width) / 2);
let watermarkEle = watermarkBase.cloneNode();
watermarkEle.style.cssText += `left: ${left}px; top: ${top}px; width: ${options.width}px; height: ${options.height}px`;
watermarkEle.style.transform = `rotate(${options.rotate}deg)`;
watermarkEle.style.opacity = options.opacity;
watermarkEle.style.fontSize = `${options.fontSize}rem`;
watermarkEle.style.fontFamily = options.fontFamily;
watermarkEle.innerHTML = options.content;
watermark._container.appendChild(watermarkEle);
}
}
//Backup for recover the watermark's container when the its DOM is removed
_wmContainer = watermark._container;
};
/**
* Rerender watermark
* @param {Watermark} watermark
* @param {Object} options
*/
var _render = function (watermark, options) {
_wmObserver.disconnect();
watermark._container.innerHTML = '';
_createWatermark(watermark, options);
_wmObserver.observe(watermark._container, {
attributes: true,
childList: true,
characterData: true,
subtree: true
});
};
/**
* Observe watermark and watermark's parentNode mutations
* @param {Watermark} watermark
*/
var _addObserve = function (watermark) {
//Observe watermark element and its child element
_wmObserver = new MutationObserver(function (mutations, observer) {
_render(watermark, watermark.options);
});
_wmObserver.observe(watermark._container, {
attributes: true,
childList: true,
characterData: true,
subtree: true
});
//Observe parent element, recreate if the element is deleted
_wmParentObserver = new MutationObserver(function (mutations) {
for (let m of mutations) {
if (
m.type === 'childList' &&
m.removedNodes.length > 0 &&
document.querySelectorAll('.cell-watermark-container').length === 0
) {
_parentEle.appendChild(_wmContainer);
}
}
});
_wmParentObserver.observe(watermark._container.parentNode, {
childList: true,
subtree: true
});
};
/**
* Window's resize listener
* @param {Watermark} watermark
*/
var _addResizeListener = function (watermark) {
_resizeHandler = function () {
//获取页面最大宽度
var _windowsWidth_n = Math.max(_parentEle.scrollWidth, _parentEle.clientWidth);
//获取页面最大高度
var _windowsHeight_n = Math.max(_parentEle.scrollHeight, _parentEle.clientHeight);
/*if (window.outerHeight !== _windowsHeight || window.outerWidth !== _windowsWidth) {
_windowsHeight = window.outerHeight;
_windowsWidth = window.outerWidth;
_render(watermark, watermark.options);
}*/
if (_windowsHeight_n !== _windowsHeight || _windowsWidth_n !== _windowsWidth) {
_windowsHeight = _windowsHeight_n;
_windowsWidth = _windowsWidth_n;
_render(watermark, watermark.options);
}
};
window.addEventListener('resize', _resizeHandler);
};
/**
* Watermark.
* Create watermark for webpage and automatic adjust when windows resize.
* @param {Object} options
* @param {String} [options.content] watermark's text
* @param {String} [options.appendTo='body'] parent of watermark's container
* @param {Number} [options.width=150] watermark's width. unit: px
* @param {Number} [options.height=20] watermark's height. unit: px
* @param {Number} [options.rowSpacing=60] row spacing of watermarks. unit: px
* @param {Number} [options.colSpacing=30] col spacing of watermarks. unit: px
* @param {Number} [options.rotate=15] watermark's tangent angle. unit: deg
* @param {Number} [options.opacity=0.1] watermark's transparency
* @param {Number} [options.fontSize=0.85] watermark's fontSize. unit: rem
* @param {Number} [options.fontFamily='inherit'] watermark's fontFamily.
* @namespace Watermark
* @class Watermark
* @version 1.0.3
* @author @Lruihao https://lruihao.cn
*/
function Watermark(options = {}) {
var _proto = Watermark.prototype;
this.options = options;
_createContainer(this);
_createWatermark(this, this.options);
_addObserve(this);
_addResizeListener(this);
/**
* Upload watermark's text content
* @param {String} content watermark's text
*/
_proto.upload = function (content) {
if (!content) {
return;
}
_wmParentObserver.disconnect();
_wmObserver.disconnect();
this.options.content = content;
for (const watermark of this._container.querySelectorAll('.cell-watermark')) {
watermark.innerHTML = content;
}
_wmParentObserver.observe(this._container.parentNode, {
childList: true,
subtree: true
});
_wmObserver.observe(this._container, {
attributes: true,
childList: true,
characterData: true,
subtree: true
});
};
/**
* Rerender watermark
* @param {Object} options
*/
_proto.render = function (options = {}) {
_render(this, Object.assign(this.options, options));
};
/**
* Force destroy watermark
*/
_proto.destroy = function () {
_wmObserver.disconnect();
_wmParentObserver.disconnect();
window.removeEventListener('resize', _resizeHandler);
this._container.parentNode.removeChild(this._container);
};
}
exports("watermark",Watermark);
})