feat: on-page Download PDF opens Letter-size printable Study Load; drop pdf-lib/background path

content.js

@@ -123,22 +123,89 @@
       header = {};
     }
 
-    const totalUnits = extractTotalUnits(document.body.innerText);
-    return { header, courses, totalUnits };
+    return { header, courses };
   }
 
-  browser.runtime.onMessage.addListener((msg, sender, sendResponse) => {
-    if (msg && msg.type === 'scrape-study-load') {
-      scrapeStudyLoad()
-        .then((data) => sendResponse({ ok: true, data }))
-        .catch((err) => sendResponse({ ok: false, error: String((err && err.message) || err) }));
-      return true; // async response
+  // ---- On-page Download PDF button ----
+  const BTN_ID = 'ismisHelperDownloadBtn';
+
+  function showToast(msg, isError) {
+    if (window.toastr) {
+      if (isError) window.toastr.error(msg);
+      else window.toastr.success(msg);
+    } else if (isError) {
+      alert(msg);
     }
-  });
+  }
+
+  function findTotalUnitsP() {
+    const ps = document.querySelectorAll('#StudyLoad p');
+    for (const p of ps) {
+      if (/Total Units/i.test(p.textContent || '')) return p;
+    }
+    return null;
+  }
+
+  async function onDownloadPdf() {
+    const btn = document.getElementById(BTN_ID);
+    try {
+      btn.disabled = true;
+      btn.innerHTML = '<i class="fa fa-spinner fa-spin"></i> Opening...';
+      const { header, courses } = await scrapeStudyLoad();
+      const included = ISMIStools.filterStudyLoadCourses(courses);
+      if (!included.length) throw new Error('No enrolled courses found.');
+      const totalUnits = ISMIStools.sumUnits(included);
+      const html = ISMIStools.buildStudyLoadHtml({ header, courses: included, totalUnits });
+      const win = window.open('', '_blank');
+      if (!win) {
+        showToast('Popup blocked — allow popups for this site, then try again.', true);
+        return;
+      }
+      win.document.write(html);
+      win.document.close();
+      showToast('Opened printable Study Load.');
+    } catch (err) {
+      showToast('Error: ' + ((err && err.message) || err), true);
+    } finally {
+      btn.disabled = false;
+      btn.innerHTML = '<i class="fa fa-download"></i> Download PDF';
+    }
+  }
+
+  function injectDownloadButton() {
+    if (document.getElementById(BTN_ID)) return;
+    const unitsP = findTotalUnitsP();
+    if (!unitsP) return;
+    const btn = document.createElement('button');
+    btn.id = BTN_ID;
+    btn.type = 'button';
+    btn.className = 'btn green pull-right';
+    btn.style.marginTop = '10px';
+    btn.innerHTML = '<i class="fa fa-download"></i> Download PDF';
+    btn.addEventListener('click', onDownloadPdf);
+    unitsP.insertAdjacentElement('afterend', btn);
+  }
+
+  function tryInjectButton() {
+    if (document.getElementById(BTN_ID)) return;
+    if (document.querySelector('#StudyLoad table.table-forum')) injectDownloadButton();
+  }
+
+  function watchStudyLoad() {
+    tryInjectButton();
+    const observer = new MutationObserver((mutations) => {
+      const inStudyLoad = mutations.some(
+        (m) => m.target && m.target.closest && m.target.closest('#StudyLoad')
+      );
+      if (inStudyLoad) tryInjectButton();
+    });
+    observer.observe(document.body, { childList: true, subtree: true });
+  }
 
   (async function init() {
     if (!(await isEnabled())) return;
     watchPrivacyModal();
     if (/\/Account\/Login/i.test(location.href)) autoLogin();
+    if (document.getElementById('StudyLoad')) watchStudyLoad();
   })();
 })();