"Add assignment" button makes it add to current category (#162)

adds to buttonFuntions.js and home.js, changing the newAssignment function so it adds to the current category filter (and if none is selected just the first category filter), and tracks what the filter is currently. I did this based off a variable and not the filter because it's easier.

public/js/buttonFunctions.js

@@ -6,7 +6,7 @@ let newAssignment = function() {
 
     currentTableData.currentTermData.classes[selected_class_i].assignments.unshift({
       "name": "Assignment",
-      "category": Object.keys(currentTableData.currentTermData.classes[selected_class_i].categories)[0],
+      "category": Object.keys(currentTableData.currentTermData.classes[selected_class_i].categories)[currentFilterRow >= 0 ? currentFilterRow : 0],
       "score": 10,
       "max_score": 10,
       "percentage": 100,

public/js/home.js

@@ -150,6 +150,10 @@ let recentActivity = new Tabulator("#recentActivity", {
         classesTable.selectRow(1);
     },
 });
+
+// Index of the row that's currently selected in the categories table
+// (gets reset to -1 whenever the class is changed)
+let currentFilterRow = -1;
 let categoriesTable = new Tabulator("#categoriesTable", {
     //	height: 400,
     selectable: 1,
@@ -173,9 +177,16 @@ let categoriesTable = new Tabulator("#categoriesTable", {
     ],
     rowClick: function(e, row) { //trigger an alert message when the row is clicked
         assignmentsTable.clearFilter();
-        assignmentsTable.addFilter([
-            {field: "category", type:"=", value: row.getData().category}
-        ]);
+
+        if (currentFilterRow !== row.getPosition()) {
+            currentFilterRow = row.getPosition();
+            assignmentsTable.addFilter([
+                {field: "category", type:"=", value: row.getData().category}
+            ]);
+        }
+        else {
+            currentFilterRow = -1;
+        }
     },
 });
 
@@ -633,7 +644,10 @@ let classesTable = new Tabulator("#classesTable", {
     ],
     rowClick: function(e, row) { // trigger an alert message when the row is clicked
         $("#mostRecentDiv").hide();
+
         assignmentsTable.clearFilter();
+        currentFilterRow = -1;
+
         document.getElementById("categoriesTable").style.display = "block";
         document.getElementById("assignmentsTable").style.display = "block";
         selected_class_i = row.getPosition();