init the awkward code

static/html/jspaint/localization/preprocess.js

@@ -0,0 +1,96 @@
+const fs = require("fs");
+const glob = require("glob");
+const parse_rc_file = require("./parse-rc-file");
+
+const base_lang = "en";
+const available_langs = fs.readdirSync(__dirname).filter((dir) => dir.match(/^\w+(-\w+)?$/));
+const target_langs = available_langs.filter((lang) => lang !== base_lang);
+
+console.log("Target languages:", target_langs);
+
+// @TODO: DRY hotkey helpers
+// & defines accelerators (hotkeys) in menus and buttons and things, which get underlined in the UI.
+// & can be escaped by doubling it, e.g. "&Taskbar && Start Menu"
+function index_of_hotkey(text) {
+	// Returns the index of the ampersand that defines a hotkey, or -1 if not present.
+
+	// return english_text.search(/(?<!&)&(?!&|\s)/); // not enough browser support for negative lookbehind assertions
+
+	// The space here handles beginning-of-string matching and counteracts the offset for the [^&] so it acts like a negative lookbehind
+	return ` ${text}`.search(/[^&]&[^&\s]/);
+}
+function has_hotkey(text) {
+	return index_of_hotkey(text) !== -1;
+}
+function remove_hotkey(text) {
+	return text.replace(/\s?\(&.\)/, "").replace(/([^&]|^)&([^&\s])/, "$1$2");
+}
+const remove_ellipsis = str => str.replace("...", "");
+
+const only_unique = (value, index, self) => self.indexOf(value) === index;
+
+const get_strings = (lang) => {
+	return glob.sync(`${__dirname}/${lang}/**/*.rc`).map(
+		(rc_file) => parse_rc_file(fs.readFileSync(rc_file, "utf16le").replace(/\ufeff/g, ""))
+	).flat();
+};
+
+const base_strings = get_strings(base_lang);
+for (const target_lang of target_langs) {
+	const target_strings = get_strings(target_lang);
+	const localizations = {};
+	const add_localization = (base_string, target_string, fudgedness) => {
+		localizations[base_string] = localizations[base_string] || [];
+		localizations[base_string].push({ target_string, fudgedness });
+	};
+	const add_localizations = (base_strings, target_strings) => {
+		for (let i = 0; i < target_strings.length; i++) {
+			const base_string = base_strings[i];
+			const target_string = target_strings[i];
+			if (base_string !== target_string && base_string && target_string) {
+				// Split strings like "&Attributes...\tCtrl+E"
+				// and "Fills an area with the current drawing color.\nFill With Color"
+				const splitter = /\t|\r?\n/;
+				if (base_string.match(splitter)) {
+					add_localizations(
+						base_string.split(splitter),
+						target_string.split(splitter)
+					);
+				} else {
+					// add_localization(base_string, target_string, 0);
+					add_localization(remove_ellipsis(base_string), remove_ellipsis(target_string), 1);
+					if (has_hotkey(base_string)) {
+						// add_localization(remove_hotkey(base_string), remove_hotkey(target_string), 2);
+						add_localization(remove_ellipsis(remove_hotkey(base_string)), remove_ellipsis(remove_hotkey(target_string)), 3);
+					}
+				}
+			}
+		}
+	};
+	add_localizations(base_strings, target_strings);
+
+	for (const base_string in localizations) {
+		const options = localizations[base_string];
+		options.sort((a, b) => a.fudgedness - b.fudgedness);
+		const unique_strings = options.map(({ target_string }) => target_string).filter(only_unique);
+		if (unique_strings.length > 1) {
+			console.warn(`Collision for "${base_string}": ${JSON.stringify(unique_strings, null, "\t")}`);
+		}
+		localizations[base_string] = unique_strings[0];
+	}
+	const js = `//
+// NOTE: This is a generated file! Don't edit it directly.
+// Eventually community translation will be set up on some translation platform.
+// 
+// Generated with: npm run update-localization
+//
+loaded_localizations("${target_lang}", ${JSON.stringify(localizations, null, "\t")});\n`;
+	fs.writeFileSync(`${__dirname}/${target_lang}/localizations.js`, js);
+}
+
+// Update available_languages list automatically!
+const file = require("path").resolve(__dirname + "/../index.html");
+let code = fs.readFileSync(file, "utf8");
+code = code.replace(/(available_languages\s*=\s*)\[[^\]]*\]/, `$1${JSON.stringify(available_langs).replace(/","/g, `", "`)}`);
+fs.writeFileSync(file, code, "utf8");
+console.log(`Updated available_languages list in "${file}"`);