ditto/src/utils/note.ts

122 lines
3.3 KiB
TypeScript

import 'linkify-plugin-hashtag';
import linkifyStr from 'linkify-string';
import linkify from 'linkifyjs';
import { nip19, nip21 } from 'nostr-tools';
import { Conf } from '@/config.ts';
import { getUrlMediaType, isPermittedMediaType } from '@/utils/media.ts';
linkify.registerCustomProtocol('nostr', true);
linkify.registerCustomProtocol('wss');
const linkifyOpts: linkify.Opts = {
render: {
hashtag: ({ content }) => {
const tag = content.replace(/^#/, '');
const href = Conf.local(`/tags/${tag}`);
return `<a class=\"mention hashtag\" href=\"${href}\" rel=\"tag\"><span>#</span>${tag}</a>`;
},
url: ({ content }) => {
try {
const { decoded } = nip21.parse(content);
const pubkey = getDecodedPubkey(decoded);
if (pubkey) {
const name = pubkey.substring(0, 8);
const href = Conf.local(`/users/${pubkey}`);
return `<span class="h-card"><a class="u-url mention" href="${href}" rel="ugc">@<span>${name}</span></a></span>`;
} else {
return '';
}
} catch {
return `<a href="${content}">${content}</a>`;
}
},
},
};
type Link = ReturnType<typeof linkify.find>[0];
interface ParsedNoteContent {
html: string;
links: Link[];
/** First non-media URL - eligible for a preview card. */
firstUrl: string | undefined;
}
/** Convert Nostr content to Mastodon API HTML. Also return parsed data. */
function parseNoteContent(content: string): ParsedNoteContent {
// Parsing twice is ineffecient, but I don't know how to do only once.
const html = linkifyStr(content, linkifyOpts);
const links = linkify.find(content).filter(isLinkURL);
const firstUrl = links.find(isNonMediaLink)?.href;
return {
html,
links,
firstUrl,
};
}
/** Remove imeta links. */
function stripimeta(content: string, tags: string[][]): string {
const imeta = tags.filter(([name]) => name === 'imeta');
if (!imeta.length) {
return content;
}
const urls = new Set(
imeta.map(([, ...values]) => values.map((v) => v.split(' ')).find(([name]) => name === 'url')?.[1]),
);
const lines = content.split('\n').reverse();
for (const line of [...lines]) {
if (line === '' || urls.has(line)) {
lines.splice(0, 1);
} else {
break;
}
}
return lines.reverse().join('\n');
}
/** Returns a matrix of tags. Each item is a list of NIP-94 tags representing a file. */
function getMediaLinks(links: Pick<Link, 'href'>[]): string[][][] {
return links.reduce<string[][][]>((acc, link) => {
const mediaType = getUrlMediaType(link.href);
if (!mediaType) return acc;
if (isPermittedMediaType(mediaType, ['audio', 'image', 'video'])) {
acc.push([
['url', link.href],
['m', mediaType],
]);
}
return acc;
}, []);
}
function isNonMediaLink({ href }: Link): boolean {
return /^https?:\/\//.test(href) && !getUrlMediaType(href);
}
/** Ensures the Link is a URL so it can be parsed. */
function isLinkURL(link: Link): boolean {
return link.type === 'url';
}
/** Get pubkey from decoded bech32 entity, or undefined if not applicable. */
function getDecodedPubkey(decoded: nip19.DecodeResult): string | undefined {
switch (decoded.type) {
case 'npub':
return decoded.data;
case 'nprofile':
return decoded.data.pubkey;
}
}
export { getMediaLinks, parseNoteContent, stripimeta };