site/quartz/plugins/transformers/description.ts
2024-04-05 02:03:11 +02:00

83 lines
2.6 KiB
TypeScript

import { Root as HTMLRoot } from "hast"
import { toString } from "hast-util-to-string"
import { QuartzTransformerPlugin } from "../types"
import { escapeHTML } from "../../util/escape"
export interface Options {
descriptionLength: number
replaceExternalLinks: boolean
}
const defaultOptions: Options = {
descriptionLength: 150,
replaceExternalLinks: true,
}
const urlRegex = new RegExp(
/(https?:\/\/)?(?<domain>([\da-z\.-]+)\.([a-z\.]{2,6})(:\d+)?)(?<path>[\/\w\.-]*)(\?[\/\w\.=&;-]*)?/,
"g",
)
export const Description: QuartzTransformerPlugin<Partial<Options> | undefined> = (userOpts) => {
const opts = { ...defaultOptions, ...userOpts }
return {
name: "Description",
htmlPlugins() {
return [
() => {
return async (tree: HTMLRoot, file) => {
let frontMatterDescription = file.data.frontmatter?.description
let text = escapeHTML(toString(tree))
if (opts.replaceExternalLinks) {
frontMatterDescription = frontMatterDescription?.replace(
urlRegex,
"$<domain>" + "$<path>",
)
text = text.replace(urlRegex, "$<domain>" + "$<path>")
}
const desc = frontMatterDescription ?? text
const sentences = desc.replace(/\s+/g, " ").split(/\.\s/)
const finalDesc: string[] = []
const len = opts.descriptionLength
let sentenceIdx = 0
let currentDescriptionLength = 0
if (sentences[0] !== undefined && sentences[0].length >= len) {
const firstSentence = sentences[0].split(" ")
while (currentDescriptionLength < len) {
const sentence = firstSentence[sentenceIdx]
if (!sentence) break
finalDesc.push(sentence)
currentDescriptionLength += sentence.length
sentenceIdx++
}
finalDesc.push("...")
} else {
while (currentDescriptionLength < len) {
const sentence = sentences[sentenceIdx]
if (!sentence) break
const currentSentence = sentence.endsWith(".") ? sentence : sentence + "."
finalDesc.push(currentSentence)
currentDescriptionLength += currentSentence.length
sentenceIdx++
}
}
file.data.description = finalDesc.join(" ")
file.data.text = text
}
},
]
},
}
}
declare module "vfile" {
interface DataMap {
description: string
text: string
}
}