/*--------------------------------------------------------------------------------------------- * Copyright (c) Microsoft Corporation. All rights reserved. * Licensed under the MIT License. See License.txt in the project root for license information. *--------------------------------------------------------------------------------------------*/ 'use strict'; import * as vscode from 'vscode'; import * as path from 'path'; import { TableOfContentsProvider } from './tableOfContentsProvider'; export interface IToken { type: string; map: [number, number]; } interface MarkdownIt { render(text: string): string; parse(text: string): IToken[]; utils: any; } const FrontMatterRegex = /^---\s*[^]*?---\s*/; export class MarkdownEngine { private md: MarkdownIt; private firstLine: number; private currentDocument: vscode.Uri; private get engine(): MarkdownIt { if (!this.md) { const hljs = require('highlight.js'); const mdnh = require('markdown-it-named-headers'); this.md = require('markdown-it')({ html: true, highlight: (str: string, lang: string) => { if (lang && hljs.getLanguage(lang)) { try { return `
${hljs.highlight(lang, str, true).value}
`;
} catch (error) { }
}
return `${this.engine.utils.escapeHtml(str)}
`;
}
}).use(mdnh, {
slugify: (header: string) => TableOfContentsProvider.slugify(header)
});
for (const renderName of ['paragraph_open', 'heading_open', 'image', 'code_block', 'blockquote_open', 'list_item_open']) {
this.addLineNumberRenderer(this.md, renderName);
}
this.addLinkNormalizer(this.md);
this.addLinkValidator(this.md);
}
return this.md;
}
private stripFrontmatter(text: string): { text: string, offset: number } {
let offset = 0;
const frontMatterMatch = FrontMatterRegex.exec(text);
if (frontMatterMatch) {
const frontMatter = frontMatterMatch[0];
offset = frontMatter.split(/\r\n|\n|\r/g).length - 1;
text = text.substr(frontMatter.length);
}
return { text, offset };
}
public render(document: vscode.Uri, stripFrontmatter: boolean, text: string): string {
let offset = 0;
if (stripFrontmatter) {
const markdownContent = this.stripFrontmatter(text);
offset = markdownContent.offset;
text = markdownContent.text;
}
this.currentDocument = document;
this.firstLine = offset;
return this.engine.render(text);
}
public parse(source: string): IToken[] {
const {text, offset} = this.stripFrontmatter(source);
return this.engine.parse(text).map(token => {
if (token.map) {
token.map[0] += offset;
}
return token;
});
}
private addLineNumberRenderer(md: any, ruleName: string): void {
const original = md.renderer.rules[ruleName];
md.renderer.rules[ruleName] = (tokens: any, idx: number, options: any, env: any, self: any) => {
const token = tokens[idx];
if ((token.level === 0 || token.type === 'list_item_open' && token.level === 1) && token.map && token.map.length) {
token.attrSet('data-line', this.firstLine + token.map[0]);
token.attrJoin('class', 'code-line');
}
if (original) {
return original(tokens, idx, options, env, self);
} else {
return self.renderToken(tokens, idx, options, env, self);
}
};
}
private addLinkNormalizer(md: any): void {
const normalizeLink = md.normalizeLink;
md.normalizeLink = (link: string) => {
try {
let uri = vscode.Uri.parse(link);
if (!uri.scheme && uri.path && !uri.fragment) {
// Assume it must be a file
if (uri.path[0] === '/') {
uri = vscode.Uri.file(path.join(vscode.workspace.rootPath || '', uri.path));
} else {
uri = vscode.Uri.file(path.join(path.dirname(this.currentDocument.path), uri.path));
}
return normalizeLink(uri.toString(true));
}
} catch (e) {
// noop
}
return normalizeLink(link);
};
}
private addLinkValidator(md: any): void {
const validateLink = md.validateLink;
md.validateLink = (link: string) => {
// support file:// links
return validateLink(link) || link.indexOf('file:') === 0;
};
}
}