#!/bin/bash

# Patch mdbook theme to add language selector and utility links

# Usage: patch-mdbook-theme.sh <coreutils-docs-dir> <coreutils-l10n-dir>

set -euo pipefail

DOCS_DIR="${1:?Usage: $0 <coreutils-docs-dir> <coreutils-l10n-dir>}"

L10N_DIR="${2:?Usage: $0 <coreutils-docs-dir> <coreutils-l10n-dir>}"

HEAD_HBS="$DOCS_DIR/theme/head.hbs"

# Convert FTL locale code to URL code: strip region when language == region

# (e.g., fr-FR -> fr, es-ES -> es) but keep distinct ones (zh-Hans, pt-BR, nb-NO)

ftl_to_url() {

local code="$1"

local lang="${code%%-*}"

local region="${code#*-}"

# If region is the language uppercased (fr-FR, es-ES, etc.), simplify to just the language

if [ "${region,,}" = "${lang,,}" ]; then

echo "$lang"

else

echo "$code"

fi

}

# Generate display name for a locale code

# Uses python3+babel if available, otherwise falls back to the code itself

locale_display_name() {

local code="$1"

if command -v python3 > /dev/null 2>&1; then

local name

name=$(python3 -c "

try:

from babel import Locale

print(Locale.parse('${code}'.replace('-', '_')).get_display_name())

except Exception:

print('${code}')

" 2>/dev/null)

# Capitalize first letter for consistency

echo "${name^}"

else

echo "$code"

fi

}

# Scan l10n repo to find which locales have translations

# Use a representative utility (ls) to find available locales

LANGS_JSON="['en', 'English']"

for ftl in "$L10N_DIR"/src/uu/ls/locales/*.ftl; do

[ -f "$ftl" ] || continue

ftl_name=$(basename "$ftl" .ftl)

[ "$ftl_name" = "en-US" ] && continue

url_code=$(ftl_to_url "$ftl_name")

display=$(locale_display_name "$ftl_name")

LANGS_JSON="$LANGS_JSON, ['$url_code', '$display']"

done

# Append styles and JS to head.hbs

cat >> "$HEAD_HBS" << 'ENDSTYLE'

<style>

.util-links {

display: flex;

gap: 12px;

align-items: center;

font-size: 0.75em;

}

.util-links a {

color: var(--links);

text-decoration: none;

}

.util-links a:hover {

text-decoration: underline;

}

.lang-selector {

position: relative;

display: inline-block;

}

.lang-selector select {

appearance: none;

background: var(--bg);

color: var(--fg);

border: 1px solid var(--table-border-color);

border-radius: 4px;

padding: 2px 20px 2px 6px;

font-size: 1em;

cursor: pointer;

}

.lang-selector::after {

content: "▾";

position: absolute;

right: 6px;

top: 50%;

transform: translateY(-50%);

pointer-events: none;

color: var(--fg);

font-size: 0.8em;

}

</style>

ENDSTYLE

cat >> "$HEAD_HBS" << 'ENDSCRIPT'

<script>

document.addEventListener('DOMContentLoaded', function() {

var path = window.location.pathname;

// Match both deployed (/coreutils/docs[-lang]/utils/X.html) and local (book[-lang]/utils/X.html)

var match = path.match(/\/(?:coreutils\/)?docs(?:-([a-zA-Z]{2}(?:-[a-zA-Z]+)?))?\/utils\/(\w+)\.html/)

|| path.match(/\/book(?:-([a-zA-Z]{2}(?:-[a-zA-Z]+)?))?\/utils\/(\w+)\.html/);

if (!match) return;

var currentLang = match[1] || 'en';

var utilName = match[2];

// Find the existing .additional div and append our links there

var additional = document.querySelector('.additional');

if (!additional) return;

var links = document.createElement('div');

links.className = 'util-links';

// Source code link

var srcLink = document.createElement('a');

srcLink.href = 'https://github.com/uutils/coreutils/tree/main/src/uu/' + utilName;

srcLink.textContent = 'Source';

srcLink.target = '_blank';

links.appendChild(srcLink);

// Report issue link

var issueLink = document.createElement('a');

issueLink.href = 'https://github.com/uutils/coreutils/issues/new?title=' + utilName + ':%20&labels=bug';

issueLink.textContent = 'Report a bug';

issueLink.target = '_blank';

links.appendChild(issueLink);

// Language selector

var langDiv = document.createElement('div');

langDiv.className = 'lang-selector';

var select = document.createElement('select');

var langs = LANGS_PLACEHOLDER;

langs.forEach(function(l) {

var opt = document.createElement('option');

opt.value = l[0];

opt.textContent = l[1];

if (l[0] === currentLang) opt.selected = true;

select.appendChild(opt);

});

select.addEventListener('change', function() {

var newLang = this.value;

var curPath = window.location.pathname;

// Replace the directory segment right before /utils/:

// .../book[-lang]/utils/X.html or .../docs[-lang]/utils/X.html

var newPath = curPath.replace(

/\/(book|docs)(?:-[a-zA-Z]{2}(?:-[a-zA-Z]+)?)?\/utils\//,

function(m, base) {

return '/' + base + (newLang === 'en' ? '' : '-' + newLang) + '/utils/';

}

);

window.location.href = newPath;

});

langDiv.appendChild(select);

links.appendChild(langDiv);

additional.appendChild(links);

// Generation date (localized) — append at the bottom of <main>

var main = document.querySelector('#mdbook-content main');

if (main) {

var genDate = document.createElement('div');

genDate.style.fontSize = '0.75em';

genDate.style.color = 'var(--fg)';

genDate.style.opacity = '0.6';

genDate.style.marginTop = '2em';

genDate.style.textAlign = 'right';

var locale = currentLang.replace('_', '-');

var dateStr = new Date(GENDATE_PLACEHOLDER).toLocaleDateString(locale, {

year: 'numeric', month: 'long', day: 'numeric'

});

genDate.textContent = dateStr;

main.appendChild(genDate);

}

});

</script>

ENDSCRIPT

# Inject the dynamically-built language list and generation date

GENDATE=$(date -u +%Y-%m-%dT%H:%M:%SZ)

sed -i "s|LANGS_PLACEHOLDER|[${LANGS_JSON}]|" "$HEAD_HBS"

sed -i "s|GENDATE_PLACEHOLDER|'${GENDATE}'|" "$HEAD_HBS"

echo "Patched $HEAD_HBS with language selector and utility links"