feat: restore direct PDF download via background; drop printdoc

background.js

@@ -0,0 +1,35 @@
+'use strict';
+
+function errMsg(err) {
+  return String((err && err.message) || err);
+}
+
+browser.runtime.onMessage.addListener((msg, sender, sendResponse) => {
+  if (msg && msg.type === 'generate-pdf') {
+    generatePdf(msg.data)
+      .then(() => sendResponse({ ok: true }))
+      .catch((err) => sendResponse({ ok: false, error: errMsg(err) }));
+    return true;
+  }
+});
+
+async function generatePdf(data) {
+  const bytes = await ISMIStools.buildStudyLoadPdf(data);
+  const blob = new Blob([bytes], { type: 'application/pdf' });
+  const url = URL.createObjectURL(blob);
+  const name = (data.header && data.header.fullName) || 'Student';
+  const filename = 'Study Load - ' + name + '.pdf';
+  try {
+    const id = await browser.downloads.download({ url, filename, saveAs: true });
+    const onChanged = (delta) => {
+      if (delta.id === id && delta.state && (delta.state.current === 'complete' || delta.state.current === 'interrupted')) {
+        browser.downloads.onChanged.removeListener(onChanged);
+        URL.revokeObjectURL(url);
+      }
+    };
+    browser.downloads.onChanged.addListener(onChanged);
+  } catch (err) {
+    URL.revokeObjectURL(url);
+    throw err;
+  }
+}