// Every locale is served from its own subdirectory, so a relative asset path silently
// changes meaning depending on which page you are on: 'logo/aegis.png' is /logo/aegis.png
// from the English page and /de/logo/aegis.png — a 404 — from the German one. The
// partner logos shipped exactly that bug, and it is invisible in development, where
// only the root page is ever open.
//
// The CSP sets base-uri 'none', so a <base href> cannot rescue relative paths either.
// Root-absolute is the only option, and this test is what keeps it that way.

import assert from 'node:assert/strict';
import { execFileSync } from 'node:child_process';
import { readFileSync } from 'node:fs';
import path from 'node:path';
import { fileURLToPath } from 'node:url';

const ROOT = fileURLToPath(new URL('..', import.meta.url));

// Directories that exist at the site root. A reference to one of them from inside a
// locale page has to start with a slash.
const ROOT_DIRS = ['logo', 'assets', 'libs', 'dist', 'config', 'src'];

// Prose about a path is not a path. A comment quoting './sw.js' to explain why it is
// wrong must not itself be reported as the thing being wrong.
const isComment = (line) => /^\s*(\/\/|\/?\*)/.test(line);

const files = execFileSync('git', ['ls-files', 'src'], { cwd: ROOT, encoding: 'utf8' })
    .trim().split('\n')
    .filter((f) => /\.(js|jsx)$/.test(f) && f !== 'src/i18n/generated.js');

const offenders = [];
for (const file of files) {
    const text = readFileSync(path.join(ROOT, file), 'utf8');
    text.split('\n').forEach((line, i) => {
        if (isComment(line)) return;
        // A quoted path that starts with a root directory name and no leading slash.
        for (const match of line.matchAll(new RegExp(`['"](?:${ROOT_DIRS.join('|')})/[A-Za-z0-9_./-]+\\.(png|jpe?g|svg|gif|webp|ico|css|mp3|mp4|webm|woff2?)['"]`, 'g'))) {
            // An ES import specifier is resolved by the bundler at build time, not by the
            // browser against the page URL, so it is not affected.
            if (/\b(import|from|require)\b/.test(line)) continue;
            offenders.push(`${file}:${i + 1}  ${match[0]}`);
        }
    });
}

// The check above only knows about root *directories*, so a root-level *file* walked
// straight past it: the Service Worker was registered as './sw.js', which asks /ar/ for
// /ar/sw.js and gets a 404. That left twelve of the thirteen pages with no worker at all
// — no offline shell, no update prompt — and it was invisible from the English page,
// which is the only one where the relative path happens to be right.
const ROOT_FILES = ['sw.js', 'manifest.json', 'meta.json', 'robots.txt', 'sitemap.xml', 'browserconfig.xml'];
for (const file of files) {
    const text = readFileSync(path.join(ROOT, file), 'utf8');
    text.split('\n').forEach((line, i) => {
        if (isComment(line)) return;
        for (const match of line.matchAll(new RegExp(`['"](?:\\./)?(?:${ROOT_FILES.join('|').replace(/\./g, '\\.')})['"]`, 'g'))) {
            if (/\b(import|from|require)\b/.test(line)) continue;
            offenders.push(`${file}:${i + 1}  ${match[0]}`);
        }
    });
}

// A worker scoped to './' controls only the directory it was registered from, so an app
// installed at /ar/ would stop being covered the moment it navigated to the root. There
// is one worker for the whole site; its scope is the whole site.
for (const file of files) {
    const text = readFileSync(path.join(ROOT, file), 'utf8');
    if (!text.includes('serviceWorker.register')) continue;
    text.split('\n').forEach((line, i) => {
        if (isComment(line)) return;
        if (/scope:\s*['"](?!\/['"])/.test(line)) offenders.push(`${file}:${i + 1}  ${line.trim()}`);
    });
}

assert.deepEqual(
    offenders, [],
    'these paths are relative and change meaning inside a locale subdirectory — make them root-absolute:\n' +
    offenders.join('\n')
);

console.log(`asset-paths-locale-safe.test.mjs: ${files.length} source files checked, no relative asset paths`);