export

src/utils/csv.js

@@ -0,0 +1,41 @@
+/** Escape a value for a CSV field ("..." double-quoting per RFC 4180). */
+function csvField(value) {
+  const text = value == null ? '' : String(value);
+  return /[";\n\r]/.test(text) ? `"${text.replace(/"/g, '""')}"` : text;
+}
+
+/**
+ * Build a CSV string from an array of row objects (keys become the header).
+ * Uses `;` as the field separator with a `sep=;` hint line so Excel opens it
+ * correctly regardless of the OS list-separator locale.
+ */
+export function toCsv(rows) {
+  if (!rows.length) return '';
+  const headers = Object.keys(rows[0]);
+  const lines = [
+    'sep=;',
+    headers.map(csvField).join(';'),
+    ...rows.map((row) => headers.map((h) => csvField(row[h])).join(';')),
+  ];
+  return lines.join('\r\n');
+}
+
+/** Trigger a browser download of the given string, encoded as Windows-1252. */
+export function downloadCsv(filename, csv) {
+  const bytes = new Uint8Array(csv.length);
+  for (let i = 0; i < csv.length; i++) {
+    const code = csv.charCodeAt(i);
+    // Windows-1252 covers the single-byte Latin-1 range + punctuation (e.g. „ " –).
+    // Category names are German/single-byte, so chars are well inside this range.
+    bytes[i] = code <= 0xff ? code : 0x3f; // '?' for any out-of-range char
+  }
+  const blob = new Blob([bytes], { type: 'text/csv;charset=windows-1252;' });
+  const url = URL.createObjectURL(blob);
+  const link = document.createElement('a');
+  link.href = url;
+  link.download = filename;
+  document.body.appendChild(link);
+  link.click();
+  document.body.removeChild(link);
+  URL.revokeObjectURL(url);
+}