createTIL.mts

#!/usr/bin/env -S pnpm tsx
import * as fs from 'fs';
import * as url from 'url';
import * as path from 'path';
import assert from 'assert';

const dirname = path.dirname(url.fileURLToPath(import.meta.url));

const [newCategory, newTopic] = process.argv.slice(2);

assert(newCategory, 'Category is required');
assert(newTopic, 'Topic is required');

const structure: Record<string, string[]> = JSON.parse(
  fs.readFileSync('structure.json', 'utf8'),
);
let output = structure;

const topicToFileName = (topic: string) =>
  topic.toLowerCase().replace(/ /g, '-').replace(/[`.]/g, '');
const catToDir = (category: string) =>
  category.toLowerCase().replace(/ /g, '-');
const fullPath = (category: string, topic: string) =>
  `${catToDir(category)}/${topicToFileName(topic)}.md`;

if (newCategory !== 'rebuild') {
  try {
    fs.mkdirSync(`${dirname}/${catToDir(newCategory)}`);
  } catch {}

  fs.writeFileSync(
    fullPath(`${dirname}/${newCategory}`, newTopic),
    `# ${newTopic}

Here is some text explaining the thing I learned, how I came across it, and
demonstrating it:

\`\`\`shell
$ echo "The example"
\`\`\`

Here is some more text maybe with the source or some additional info.
`,
    { encoding: 'utf8', flag: 'wx' },
  );

  const sortLowerCase = (a, b) =>
    topicToFileName(a) < topicToFileName(b) ? -1 : 1;

  structure[newCategory] = (structure[newCategory] || [])
    .concat([newTopic])
    .sort(sortLowerCase);
  output = Object.keys(structure)
    .sort((a, b) => (catToDir(a) < catToDir(b) ? -1 : 1))
    .reduce((acc, cat) => {
      acc[cat] = structure[cat];
      return acc;
    }, {});

  fs.writeFileSync('structure.json', JSON.stringify(output, null, 2), 'utf8');
}

const tils = Object.values(structure);
const tilCount = tils.reduce((acc, tils) => acc + tils.length, 0);

const readme = fs.createWriteStream('README.md', 'utf8');
readme.write(`# TIL

> Today I Learned

A collection of concise write-ups on small things I learn day to day across a
variety of languages and technologies. Sometimes I find them by knowing what I'm
looking for. Other times I go looking for anything that will help. Most times I
end up saying "neat" and creating an entry.

These TILs are a mix between "this is a useful thing that I learned that could
help others" and "this is something really annoying that took forever to find
out and I know I'll come across it again at some point so I want it committed
for posterity".

${tilCount} TILs across ${tils.length} categories and growing!

---

### Categories

`);

const categories = ['', '---', ''];
Object.keys(output).forEach((category) => {
  readme.write(`- [${category}](#${category.replace(/ /g, '-')})\n`);
  categories.push(
    `### ${category}`,
    '',
    ...structure[category].map(
      (topic) => `- [${topic}](${fullPath(category, topic)})`,
    ),
    '',
  );
});

readme.write(categories.join('\n'));
readme.write(`
## About

I shamelessly stole this idea from
[jbranchaud/til](https://github.com/jbranchaud/til).

## Other TIL Collections

- [jwworth/til](https://github.com/jwworth/til)
- [thoughtbot/til](https://github.com/thoughtbot/til)
- [jbranchaud/til](https://github.com/jbranchaud/til)

## License

This repository is licensed under the MIT license. See \`LICENSE\` for
details.
`);