Add Social Security and Medicare taxes

[inverse-tax] / tax_ui.js

diff --git a/tax_ui.js b/tax_ui.js
index 0117dcc19df4ae62c77bc4265aa5e0c00644e538..1148f54246986fa27fe86d349f9d9a96af710e1a 100644 (file)
--- a/tax_ui.js
+++ b/tax_ui.js
@@ -10,17 +10,22 @@ function format_number(n) {
 }
 
 function calculate() {
-  const table1 = load_tax_table('tax_table_1', 'deductible_1');
-  const table2 = load_tax_table('tax_table_2', 'deductible_2');
+  const tax_tables = [
+    load_tax_table('tax_table_1', 'deductible_1'),
+    load_tax_table('tax_table_2', 'deductible_2'),
+    load_tax_table('tax_table_3'),
+    load_tax_table('tax_table_4')
+  ];
   const after_tax = parseFloat(document.getElementById('after_tax').value);
 
-  const before_tax = invert(merge_tax_tables(table1, table2))(after_tax);
-
-  const tax1 = tax(table1, before_tax);
-  const tax2 = tax(table2, before_tax);
+  const merged_tax_table = tax_tables.reduce(merge_tax_tables);
+  const before_tax = invert(merged_tax_table)(after_tax);
+  const taxes = tax_tables.map(t => tax(t, before_tax));
 
   document.getElementById('before_tax').textContent = format_number(before_tax);
-  document.getElementById('tax_1').textContent = format_number(tax1);
-  document.getElementById('tax_2').textContent = format_number(tax2);
-  document.getElementById('after_tax_verification').textContent = format_number(before_tax - (tax1 + tax2));
+  document.getElementById('tax_1').textContent = format_number(taxes[0]);
+  document.getElementById('tax_2').textContent = format_number(taxes[1]);
+  document.getElementById('tax_3').textContent = format_number(taxes[2]);
+  document.getElementById('tax_4').textContent = format_number(taxes[3]);
+  document.getElementById('after_tax_verification').textContent = format_number(before_tax - sum(taxes));
 }