Refaktorisierungs-Optionen und Fix für Zahlen-Parsing

hugo/layouts/conversion/single.html

@@ -79,7 +79,7 @@
 					<div class="text-center sm:pt-6">
 						<button type="button"
 							@click="navigate(
-								$el.dataset.swapUrl, prettyNumber(convert(prepareValue(inputValue))))"
+								$el.dataset.swapUrl, prettyNumber(convert(parseNumber(inputValue))))"
 							data-swap-url="/{{ .Params.to }}-in-{{ .Params.from }}/"
 							class="inline-flex items-center text-sm
 								font-medium text-primary
@@ -145,7 +145,7 @@
 					</label>
 					<input type="text" id="result"
 						disabled
-						:value="prettyNumber(convert(prepareValue(inputValue)))"
+						:value="prettyNumber(convert(parseNumber(inputValue)))"
 						class="textinput mt-1 block w-full">
 				</div>
 			</div>

hugo/static/js/converter.js

@@ -44,32 +44,35 @@ function prettyNumber(num, minPrecision, maxPrecision) {
 }
 
 /**
- * Parses a German number string.
- * Accepts both comma and dot as decimal separator.
- * @param {string} input
- * @returns {string} Normalized string with dot as decimal
+ * Parses a number string for conversion.
+ * Accepts both German (1.234,56) and US (1,234.56) notation.
+ * The last dot or comma is always the decimal separator;
+ * all preceding ones are treated as thousand separators and removed.
+ * Invalid or empty input returns Decimal(0).
+ * @param {string} input - User input from field
+ * @returns {Decimal} Parsed Decimal value
  */
 function parseNumber(input) {
-	if (!input) return '0';
-	const hasComma = input.indexOf(',') !== -1;
-	const hasDot = input.indexOf('.') !== -1;
-	if (hasComma && hasDot) {
-		return input.replace(/\./g, '').replace(/,/g, '.') || '0';
-	}
-	return input.replace(/,/g, '.') || '0';
-}
-
-/**
- * Prepares input value for conversion.
- * Returns a Decimal, or 1 if input is empty.
- * @param {string} input - User input from field
- * @returns {Decimal} Prepared value
- */
-function prepareValue(input) {
 	if (!input || input.trim() === '') {
-		return new Decimal(1);
+		return new Decimal(0);
+	}
+	const trimmed = input.trim();
+	const lastDot = trimmed.lastIndexOf('.');
+	const lastComma = trimmed.lastIndexOf(',');
+	const lastSep = Math.max(lastDot, lastComma);
+	let normalized;
+	if (lastSep === -1) {
+		normalized = trimmed;
+	} else {
+		const beforeSep = trimmed.slice(0, lastSep).replace(/[.,]/g, '');
+		const afterSep = trimmed.slice(lastSep + 1);
+		normalized = beforeSep + '.' + afterSep;
+	}
+	try {
+		return new Decimal(normalized);
+	} catch (e) {
+		return new Decimal(0);
 	}
-	return new Decimal(input.replace(/,/g, '.'));
 }
 
 /**