quartz-research-note/quartz/plugins/transformers/toc.ts
Jacky Zhao b8c011410d toc
2023-06-09 23:06:02 -07:00

73 lines
1.7 KiB
TypeScript

import { PluggableList } from "unified"
import { QuartzTransformerPlugin } from "../types"
import { Root } from "mdast"
import { visit } from "unist-util-visit"
import { toString } from "mdast-util-to-string"
import { slugAnchor } from "../../path"
export interface Options {
maxDepth: 1 | 2 | 3 | 4 | 5 | 6,
minEntries: 1,
showByDefault: boolean
}
const defaultOptions: Options = {
maxDepth: 3,
minEntries: 1,
showByDefault: true,
}
interface TocEntry {
depth: number,
text: string,
slug: string
}
export class TableOfContents extends QuartzTransformerPlugin {
name = "TableOfContents"
opts: Options
constructor(opts?: Partial<Options>) {
super()
this.opts = { ...defaultOptions, ...opts }
}
markdownPlugins(): PluggableList {
return [() => {
return async (tree: Root, file) => {
const display = file.data.frontmatter?.enableToc ?? this.opts.showByDefault
if (display) {
const toc: TocEntry[] = []
let highestDepth: number = this.opts.maxDepth
visit(tree, 'heading', (node) => {
if (node.depth <= this.opts.maxDepth) {
const text = toString(node)
highestDepth = Math.min(highestDepth, node.depth)
toc.push({
depth: node.depth,
text,
slug: slugAnchor.slug(text)
})
}
})
if (toc.length > this.opts.minEntries) {
file.data.toc = toc.map(entry => ({ ...entry, depth: entry.depth - highestDepth }))
}
}
}
}]
}
htmlPlugins(): PluggableList {
return []
}
}
declare module 'vfile' {
interface DataMap {
toc: TocEntry[]
}
}