books-cli/lib/Prism.js

由于本人经常性的写一些文档，然后现有的很多插件版本各方面存在问题，甚至还有一些作者已经放弃维护了，所以决定自己写一个综合性的插件用来满足个人需求。

/**
 * 代码高亮
 */
var Prism = require('prismjs');
var languages = require('prismjs').languages;
var cheerio = require('cheerio');

var DEFAULT_LANGUAGE = 'markup';
var MAP_LANGUAGES = {
    'py': 'python',
    'js': 'javascript',
    'rb': 'ruby',
    'cs': 'csharp',
    'sh': 'bash',
    'shell': 'bash',
    'html': 'markup'
};

// Base languages syntaxes (as of prism@1.6.0), extended by other syntaxes.
// They need to be required before the others.
var PRELUDE = [
    'markup-templating', 'clike', 'javascript', 'markup', 'c', 'ruby', 'css',
    // The following depends on previous ones
    'java', 'php'
];
PRELUDE.map(requireSyntax);

/**
 * Load the syntax definition for a language id
 */
function requireSyntax(lang) {
    require('prismjs/components/prism-' + lang + '.js');
}

const cssNames = ['prismjs/themes/prism-okaidia.css'];
const assets = {
    'prismjs/themes': 'prismjs/themes/prism-okaidia.css'
};

function code_highlighted(body, lang) {
    var highlighted = '';
    if (lang !== undefined) {
        lang = lang.toLowerCase();
        lang = MAP_LANGUAGES[lang] || lang;
        // Try and find the language definition in components folder
        if (!languages[lang]) {
            try {
                requireSyntax(lang);
            } catch (e) {
                console.warn('未能加载 prism 语法: ' + lang);
                console.warn(e);
            }
        }
    }
    if (!languages[lang]) lang = DEFAULT_LANGUAGE;

    // Check against html, prism "markup" works for this
    if (lang === 'html') {
        lang = 'markup';
    }

    try {
        // The process can fail (failed to parse)
        highlighted = Prism.highlight(body, languages[lang]);
    } catch (e) {
        console.warn('高亮代码失败:');
        console.warn(e);
        highlighted = body;
    }
    return highlighted;
}

function hooks_page(page) {
    var highlighted = false;
    var $ = cheerio.load(page.content);
    $('pre').each(function () {
        highlighted = true;
        const $this = $(this);
        $this.addClass('language-');
    });
    if (highlighted) {
        page.content = $("body").html();
    }
    return page;
}

module.exports = {
    cssNames,
    assets,
    code_highlighted,
    hooks_page
};