/**
 * Harvest EN→locale phrase map from already-translated message keys,
 * then merge into phrase-map.json (does not overwrite non-empty existing locales).
 *
 * Run: node apps/web/scripts/harvest-phrase-map.mjs
 */
import fs from "node:fs";
import path from "node:path";
import { fileURLToPath } from "node:url";

const __dirname = path.dirname(fileURLToPath(import.meta.url));
const messagesDir = path.resolve(__dirname, "../src/lib/i18n/messages");
const mapPath = path.join(__dirname, "phrase-map.json");
const LOCALES = ["es", "fr", "de", "it", "pt", "nl", "pl", "ja"];

function parseMessageDict(source) {
	const dict = {};
	const re = /"([^"\\]+)"\s*:\s*((?:"(?:\\.|[^"\\])*")|(?:`(?:\\.|[^`\\])*`))/gs;
	let m;
	while ((m = re.exec(source))) {
		const key = m[1];
		const raw = m[2];
		dict[key] = raw.startsWith("`")
			? raw.slice(1, -1).replace(/\\`/g, "`").replace(/\\\$/g, "$").replace(/\\n/g, "\n")
			: JSON.parse(raw);
	}
	return dict;
}

function load(code) {
	return parseMessageDict(fs.readFileSync(path.join(messagesDir, `${code}.ts`), "utf8"));
}

const en = load("en");
const packs = Object.fromEntries(LOCALES.map((c) => [c, load(c)]));
const map = fs.existsSync(mapPath) ? JSON.parse(fs.readFileSync(mapPath, "utf8")) : {};

let harvestedPhrases = 0;
let filledSlots = 0;
let newPhrases = 0;

for (const [key, enVal] of Object.entries(en)) {
	if (!enVal || typeof enVal !== "string") continue;
	const byLoc = {};
	let good = 0;
	for (const code of LOCALES) {
		const v = packs[code][key];
		if (typeof v === "string" && v.trim() && v !== enVal) {
			byLoc[code] = v;
			good += 1;
		}
	}
	if (good < 4) continue;

	const existing = map[enVal] ?? {};
	let changed = false;
	const next = { ...existing };
	for (const code of LOCALES) {
		if ((!next[code] || !String(next[code]).trim()) && byLoc[code]) {
			next[code] = byLoc[code];
			filledSlots += 1;
			changed = true;
		}
	}
	if (changed) {
		if (!map[enVal]) newPhrases += 1;
		map[enVal] = next;
		harvestedPhrases += 1;
	}
}

fs.writeFileSync(mapPath, JSON.stringify(map, null, "\t") + "\n", "utf8");
console.log({
	phraseCount: Object.keys(map).length,
	harvestedPhrases,
	newPhrases,
	filledSlots,
});