import { frontmatter } from './utils/frontmatter.js';

import { mkdir, readdir, readFile, writeFile } from 'fs/promises';

import { readFileSync } from 'fs';

import { glob } from 'glob10';

import yaml from 'js-yaml';

import sortBy from 'lodash/sortBy.js';

import { join } from 'path';

import { LOCALES } from './actions/utils/constants.js';

if (process.env.BUILD_LANG !== 'en') {

await mkdir('./public').catch(() => null);

writeFile('./public/_redirects', '', 'utf-8');

console.log('`BUILD_LANG` is not `en`, writting empty _redirects file');

process.exit();

}

// from -> to key/value structure, since redirects are a 1:many relationship.

// ie, redirecting _from_ `/docs/security` can only redirect to one place,

// but many paths can redirect _to_ `/docs/security/overview`

const redirects = new Map();

const mdxPaths = await glob('src/content/docs/**/*.{md,mdx}');

const installYamlPaths = await glob('src/install/config/**/*.yaml');

const urlFromFsPath = (fspath) =>

fspath.replace(/src\/content/, '').replace(/\.mdx?$/, '');

// external redirects

// take priority over frontmatter defined redirects

const externalRedirects = JSON.parse(

await readFile('./src/data/external-redirects.json', 'utf-8')

);

for (const redirect of externalRedirects) {

const to = redirect.url;

for (const from of redirect.paths) {

redirects.set(from, to);

}

}

// manual redirects (for non 'src/content/docs' md|x pages)

// take priority over frontmatter defined redirects

const manualRedirects = JSON.parse(

await readFile('./src/data/manual-redirects.json', 'utf-8')

);

for (const redirect of manualRedirects) {

redirects.set(redirect.from, redirect.to);

}

for (const path of mdxPaths) {

const contents = await readFile(join(process.cwd(), path), 'utf-8');

const to = urlFromFsPath(path);

const { attributes } = frontmatter(contents);

const enRedirects = attributes.redirects ?? [];

enRedirects.forEach((from) => redirects.set(from, to));

for (const locale of LOCALES) {

const localizedTo = `/${locale}${to}`;

const localizedRedirects = enRedirects.map((from) => `/${locale}${from}`);

localizedRedirects.forEach((from) => redirects.set(from, localizedTo));

}

}

// install config redirects

for (const path of installYamlPaths) {

const contents = await yaml.load(readFileSync(join(process.cwd(), path)));

const to = `/install/${contents.agentName}`;

const enRedirects = contents.redirects ?? [];

enRedirects.forEach((from) => redirects.set(from, to));

for (const locale of LOCALES) {

const localizedTo = `/${locale}${to}`;

const localizedRedirects = enRedirects.map((from) => `/${locale}${from}`);

localizedRedirects.forEach((from) => redirects.set(from, localizedTo));

}

}

// adds a rewrite so these URLs work:

// `release-notes/agent-release-notes/<agent>/current`

const AGENT_RELEASE_NOTES_DIR =

'./src/content/docs/release-notes/agent-release-notes';

const agentDirs = await readdir(AGENT_RELEASE_NOTES_DIR);

const currentReleaseNotesRedirects = await Promise.all(

agentDirs.map(async (agentDir) => {

const notesDir = join(AGENT_RELEASE_NOTES_DIR, agentDir);

const releaseNoteDirs = (await readdir(notesDir)).map((releaseNote) =>

join(notesDir, releaseNote)

);

const releaseNotes = (

await Promise.all(

releaseNoteDirs.map(async (path) => {

const contents = await readFile(path);

const {

attributes: { releaseDate },

} = frontmatter(contents);

return [path, releaseDate ? new Date(releaseDate) : null];

})

)

).filter(([_path, date]) => date != null);

// this is in ascending order, so the last item is the most recent

const sortedReleaseNotes = sortBy(releaseNotes, ([_path, date]) => date);

const current = sortedReleaseNotes

.at(-1)[0]

.replace('src/content', '')

.replace(/\.mdx$/, '');

const agentPath = join(AGENT_RELEASE_NOTES_DIR, agentDir).replace(

'src/content',

''

);

return [join(agentPath, 'current'), [current, 200]];

})

);

currentReleaseNotesRedirects.forEach(([path, to]) => {

redirects.set(path, to);

});

const redirectsList = Array.from(redirects.entries())

.map(([from, to]) => {

if (typeof to === 'string') {

return {

from,

to,

status: 301,

};

}

const [path, status] = to;

return {

from,

to: path,

status,

};

})

.map(({ from, to, status }) => `${from} ${to} ${status}`)

.join('\n');

let redirectsAndRewrites = `${redirectsList}`;

// rewrites with splats for i18n sites

LOCALES.forEach(

(locale) =>

(redirectsAndRewrites += `\n/${locale}/* https://docs-website-${locale}.netlify.app/${locale}/:splat 200!`)

);

await mkdir('./public').catch(() => null);

writeFile('./public/_redirects', redirectsAndRewrites, 'utf-8');