gmi-web/to-html.js
2021-01-29 22:32:30 +00:00

96 lines
3 KiB
JavaScript

const fs = require("fs");
const path = require("path");
const TOKENS_EXT = /\.tokens\.json$/;
// https://developer.mozilla.org/en-US/docs/Web/Media/Formats
const IMG_EXT = (exports.IMG_EXT = /\.(apng|avif|gif|jpg|jpeg|jfif|pjpeg|pjp|png|svg|webp)$/);
const AUDIO_EXT = (exports.AUDIO_EXT = /\.(mp3|wav|aac|aacp|mpeg|off|flac)$/);
const VIDEO_EXT = (exports.VIDEO_EXT = /\.(mp4|webm)$/);
const BASE_STYLE = (exports.baseStyle =
"<style>p,a,pre,h1,h2,h3,ul,blockquote,img,audio,video{display:block;max-width:100%;margin:0;padding:0;overflow-wrap:anywhere;}</style>");
const toHTML = (exports.toHTML = (file, options) => `<!DOCTYPE html>
<html style="${options.override}">
${head(file.path, options)}
<body>
${gemtext(JSON.parse(file.contents.toString("utf8")), options)}
</body>
</html>
`);
module.exports = (options) => (file, cb) => {
if (!TOKENS_EXT.test(file.path)) return cb(null);
file.contents = Buffer.from(toHTML(file, options));
file.path = file.path.replace(TOKENS_EXT, ".html");
if (options.verbose) console.log(file.path);
return cb(null, file);
};
// TODO: meta: language, description, canonical
function head(file, options) {
return `<head>
<meta charset="utf-8">
<meta name="viewport" content="width=device-width,initial-scale=1">${
!options.css
? BASE_STYLE
: `\n<meta name="color-scheme" content="dark light">\n<style>${fs.readFileSync(
path.resolve(__dirname, "./gmi.min.css"),
"utf8"
)}</style>`
}
</head>
`;
}
function gemtext(tokens, options) {
let body = [];
let cursor = tokens.shift();
while (tokens.length) {
if (cursor.pre) {
body.push(`<pre${cursor.alt ? `title="${cursor.alt}"` : ""}>`);
const closing = tokens.findIndex((token) => token.pre);
body = body.concat(tokens.slice(0, closing).map(({ text }) => text));
body.push("</pre>");
tokens = tokens.slice(closing + 1);
}
if (cursor.li) {
body.push(`<ul>`);
const closing = tokens.findIndex((token) => !token.li);
body = body.concat(tokens.slice(0, closing).map(line));
body.push("</ul>");
tokens = tokens.slice(closing + 1);
}
body.push(line(cursor, options));
cursor = tokens.shift();
}
return body.join("\n");
}
function line(
{ text, href, title, pre, alt, h1, h2, h3, li, quote },
{ inline }
) {
if (text) return `<p>${text}</p>`;
if (href) {
if (inline.images && IMG_EXT.test(href))
return `<img src="${href}" title="${title}"/>`;
if (inline.audio && AUDIO_EXT.test(href))
return `<audio controls src="${href}" title="${title}"></audio>`;
if (inline.video && VIDEO_EXT.test(href))
return `<video controls src="${href}" title="${title}"/></video>`;
return `<a href="${href}">${title || href}</a>`;
}
if (h1) return `<h1>${h1}</h1>`;
if (h2) return `<h2>${h2}</h2>`;
if (h3) return `<h3>${h3}</h3>`;
if (li) return `<li>${li}</li>`;
if (quote) return `<blockquote>${quote}</blockquote>`;
return `<p><br></p>`;
}
function omit(key, obj) {
const { [key]: omitted, ...rest } = obj;
return rest;
}