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

172 lines
5.8 KiB
TypeScript

import { QuartzTransformerPlugin } from "../types"
import {
FullSlug,
RelativeURL,
SimpleSlug,
TransformOptions,
stripSlashes,
simplifySlug,
splitAnchor,
transformLink,
joinSegments,
} from "../../util/path"
import path from "path"
import { visit } from "unist-util-visit"
import isAbsoluteUrl from "is-absolute-url"
import { Root } from "hast"
interface Options {
/** How to resolve Markdown paths */
markdownLinkResolution: TransformOptions["strategy"]
/** Strips folders from a link so that it looks nice */
prettyLinks: boolean
openLinksInNewTab: boolean
lazyLoad: boolean
externalLinkIcon: boolean
}
const defaultOptions: Options = {
markdownLinkResolution: "absolute",
prettyLinks: true,
openLinksInNewTab: false,
lazyLoad: false,
externalLinkIcon: true,
}
export const CrawlLinks: QuartzTransformerPlugin<Partial<Options> | undefined> = (userOpts) => {
const opts = { ...defaultOptions, ...userOpts }
return {
name: "LinkProcessing",
htmlPlugins(ctx) {
return [
() => {
return (tree: Root, file) => {
const curSlug = simplifySlug(file.data.slug!)
const outgoing: Set<SimpleSlug> = new Set()
const transformOptions: TransformOptions = {
strategy: opts.markdownLinkResolution,
allSlugs: ctx.allSlugs,
}
visit(tree, "element", (node, _index, _parent) => {
// rewrite all links
if (
node.tagName === "a" &&
node.properties &&
typeof node.properties.href === "string"
) {
let dest = node.properties.href as RelativeURL
const classes = (node.properties.className ?? []) as string[]
const isExternal = isAbsoluteUrl(dest)
classes.push(isExternal ? "external" : "internal")
if (isExternal && opts.externalLinkIcon) {
node.children.push({
type: "element",
tagName: "svg",
properties: {
class: "external-icon",
viewBox: "0 0 512 512",
},
children: [
{
type: "element",
tagName: "path",
properties: {
d: "M320 0H288V64h32 82.7L201.4 265.4 178.7 288 224 333.3l22.6-22.6L448 109.3V192v32h64V192 32 0H480 320zM32 32H0V64 480v32H32 456h32V480 352 320H424v32 96H64V96h96 32V32H160 32z",
},
children: [],
},
],
})
}
// Check if the link has alias text
if (
node.children.length === 1 &&
node.children[0].type === "text" &&
node.children[0].value !== dest
) {
// Add the 'alias' class if the text content is not the same as the href
classes.push("alias")
}
node.properties.className = classes
if (opts.openLinksInNewTab) {
node.properties.target = "_blank"
}
// don't process external links or intra-document anchors
const isInternal = !(isAbsoluteUrl(dest) || dest.startsWith("#"))
if (isInternal) {
dest = node.properties.href = transformLink(
file.data.slug!,
dest,
transformOptions,
)
// url.resolve is considered legacy
// WHATWG equivalent https://nodejs.dev/en/api/v18/url/#urlresolvefrom-to
const url = new URL(dest, "https://base.com/" + stripSlashes(curSlug, true))
const canonicalDest = url.pathname
let [destCanonical, _destAnchor] = splitAnchor(canonicalDest)
if (destCanonical.endsWith("/")) {
destCanonical += "index"
}
// need to decodeURIComponent here as WHATWG URL percent-encodes everything
const full = decodeURIComponent(stripSlashes(destCanonical, true)) as FullSlug
const simple = simplifySlug(full)
outgoing.add(simple)
node.properties["data-slug"] = full
}
// rewrite link internals if prettylinks is on
if (
opts.prettyLinks &&
isInternal &&
node.children.length === 1 &&
node.children[0].type === "text" &&
!node.children[0].value.startsWith("#")
) {
node.children[0].value = path.basename(node.children[0].value)
}
}
// transform all other resources that may use links
if (
["img", "video", "audio", "iframe"].includes(node.tagName) &&
node.properties &&
typeof node.properties.src === "string"
) {
if (opts.lazyLoad) {
node.properties.loading = "lazy"
}
if (!isAbsoluteUrl(node.properties.src)) {
let dest = node.properties.src as RelativeURL
dest = node.properties.src = transformLink(
file.data.slug!,
dest,
transformOptions,
)
node.properties.src = dest
}
}
})
file.data.links = [...outgoing]
}
},
]
},
}
}
declare module "vfile" {
interface DataMap {
links: SimpleSlug[]
}
}