【这是 Reading mode for mobile 的功能插件，无法单独工作】对代码块进行高亮
// ==UserScript==
// @name [RMFM addons]代码高亮
// @namespace RMFM_code_highlight
// @version 0.0.2
// @description 【这是 Reading mode for mobile 的功能插件，无法单独工作】对代码块进行高亮
// @author 稻米鼠
// @icon https://i.v2ex.co/UuYzTkNus.png
// @supportURL https://meta.appinn.net/t/23292
// @contributionURL https://afdian.net/@daomishu
// @contributionAmount 8.88
// @antifeature payment 主脚本（Reading mode for mobile）为付费脚本
// @match *://*/*
// @require https://cdnjs.cloudflare.com/ajax/libs/highlight.js/11.4.0/highlight.min.js
// @grant none
// ==/UserScript==
(function() {
'use strict';
const codeStyle = `pre code.hljs{display:block;overflow-x:auto;padding:1em}code.hljs{padding:3px 5px}.hljs{color:#abb2bf;background:#282c34}.hljs-comment,.hljs-quote{color:#5c6370;font-style:italic}.hljs-doctag,.hljs-formula,.hljs-keyword{color:#c678dd}.hljs-deletion,.hljs-name,.hljs-section,.hljs-selector-tag,.hljs-subst{color:#e06c75}.hljs-literal{color:#56b6c2}.hljs-addition,.hljs-attribute,.hljs-meta .hljs-string,.hljs-regexp,.hljs-string{color:#98c379}.hljs-attr,.hljs-number,.hljs-selector-attr,.hljs-selector-class,.hljs-selector-pseudo,.hljs-template-variable,.hljs-type,.hljs-variable{color:#d19a66}.hljs-bullet,.hljs-link,.hljs-meta,.hljs-selector-id,.hljs-symbol,.hljs-title{color:#61aeee}.hljs-built_in,.hljs-class .hljs-title,.hljs-title.class_{color:#e6c07b}.hljs-emphasis{font-style:italic}.hljs-strong{font-weight:700}.hljs-link{text-decoration:underline}
pre > div.code-copy-button {
position: absolute;
top: 4px;
right: 18px;
width: 18px;
height: 18px;
background-color: rgba(255, 255, 255, .3);
border: 1px solid rgba(255, 255, 255, .4);
border-radius: 2px;
}
pre > div.code-copy-button:hover {
background-color: rgba(255, 255, 255, .6);
border: 1px solid rgba(255, 255, 255, .7);
}
pre > div.code-copy-button::before,
pre > div.code-copy-button::after {
content: ' ';
box-sizing: border-box;
position: absolute;
width: 9px;
height: 12px;
border: 2px solid rgba(0, 0, 0, .5);
border-radius: 2px;
}
pre > div.code-copy-button::before {
left: 3px;
top: 2px;
}
pre > div.code-copy-button::after {
right: 3px;
bottom: 2px;
}`
/**
* 为代码块生成行号图片
*
* @param {string|number} num 行号的数字
* @param {string} style 相关的样式，字号、行高和字体
* @return {string} 返回 base64 格式的图片地址
*/
const generateLineNumber = (num, style)=>{
const canvas = document.createElement('canvas')
const ctx = canvas.getContext('2d')
const context = {
font: style.fontSize + ' ' + (style.fontFamily ? style.fontFamily : window.getComputedStyle(document.body).fontFamily),
textAlign: "right",
fillStyle: "#999999",
}
for(const s in context){ ctx[s] = context[s] }
style.width = ctx.measureText(num).width
style.height = Number(style.lineHeight.replace('px', ''))
canvas.width = style.width
canvas.height = style.height
for(const s in context){ ctx[s] = context[s] }
const textY = style.height/2+Number(style.fontSize.replace('px', ''))/2
ctx.fillText(num, style.width, textY)
return canvas.toDataURL("image/png")
}
/**
* 为代码块设置行号
*
* @param {HTMLElement} codeEl
*/
const setLineNumber = (codeEl)=>{
const codeEls = codeEl ? [codeEl] : []
codeEls.forEach(cEl=>{
const cElStyle = window.getComputedStyle(cEl)
const style = {
fontSize: cElStyle.fontSize,
fontFamily: cElStyle.fontFamily,
lineHeight: cElStyle.lineHeight,
// lineHeight: cElStyle.fontSize.replace('px', '')*1.2+'px',
}
cEl.innerHTML = cEl.innerHTML
.split(/\n|<br[^>]?>/gi)
.map((lineCode, index)=>{
const lineNum = index+1
const lineBG = generateLineNumber(lineNum, style)
return '<div class="rmfm-code-line"><div class="rmfm-code-line-num" date-line-num="'+lineNum+'" style="background-image: url('+lineBG+')"></div>'+lineCode+'</div>'
})
.join('')
})
}
const copyParentText = function(){
const textArea = document.createElement('textarea')
textArea.setAttribute('readonly', 'readonly')
textArea.value = this.parentElement.innerText
document.body.appendChild(textArea)
textArea.select()
document.execCommand('copy')
document.body.removeChild(textArea)
alert('Code is copied.')
}
const opt = window.RMFM ? window.RMFM : window.RMFM={}
const addons = (opt.addons && opt.addons instanceof Array) ? opt.addons : opt.addons=[]
const eventRemver = []
addons.push({
name: 'Code block highlight',
contentStyle: codeStyle,
contentFilter: (glo, contentEl)=>{
contentEl.querySelectorAll('pre').forEach(pre=>{
const codeEl = pre.querySelector('code')
const copyButton = document.createElement('div')
copyButton.className = 'code-copy-button'
pre.appendChild(copyButton)
copyButton.addEventListener('click', copyParentText)
eventRemver.push(()=>{
copyButton.removeEventListener('click', copyParentText)
})
if(typeof(hljs) === "undefined") return
hljs.highlightBlock(codeEl)
setLineNumber(codeEl)
})
},
onMainHide: ()=>{
while(eventRemver.length){
(eventRemver.shift())()
}
}
})
})()