add auto-calculation of Itr and Ao form and also back-to dashboard button commit

static/js/itr_calc.js

@@ -0,0 +1,83 @@
+document.addEventListener("DOMContentLoaded", function () {
+    const fields = [
+        "gross_total_income", "disallowance_14a", "disallowance_37",
+        "deduction_80ia_business", "deduction_80ia_misc", "deduction_80ia_other",
+        "deduction_sec37_disallowance", "deduction_80g", "net_taxable_income",
+        "tax_30_percent", "tax_book_profit_18_5", "tax_payable", "surcharge_12",
+        "edu_cess_3", "total_tax_payable", "mat_credit", "interest_234c",
+        "total_tax", "advance_tax", "tds", "tcs", "tax_on_assessment", "refund"
+    ];
+
+    function getValue(id) {
+        return parseFloat(document.getElementsByName(id)[0].value) || 0;
+    }
+
+    function setValue(id, val) {
+        document.getElementsByName(id)[0].value = val.toFixed(2);
+    }
+
+    function calculate() {
+
+        let gross_total_income = getValue("gross_total_income");
+        let disallowance_14a = getValue("disallowance_14a");
+        let disallowance_37 = getValue("disallowance_37");
+
+        // FORMULAS
+        setValue("gross_total_income", disallowance_37 + gross_total_income);
+        setValue("disallowance_37", disallowance_14a + disallowance_37);
+
+        // Deductions
+        let d80_business = getValue("deduction_80ia_business");
+        let d80_misc = getValue("deduction_80ia_misc");
+        let d80_other = getValue("deduction_80ia_other");
+
+        let deduction_sec37 = d80_business + d80_misc + d80_other - 1.35;
+        setValue("deduction_sec37_disallowance", deduction_sec37);
+
+        let deduction_80g = getValue("deduction_80g");
+
+        // Net taxable income
+        let net_taxable_income = gross_total_income - deduction_sec37 - deduction_80g;
+        setValue("net_taxable_income", net_taxable_income);
+
+        // Tax calculations
+        setValue("tax_30_percent", net_taxable_income * 0.30);
+
+        let tax_book_profit = getValue("tax_book_profit_18_5");
+        setValue("tax_payable", tax_book_profit);
+
+        let surcharge = tax_book_profit * 0.12;
+        setValue("surcharge_12", surcharge);
+
+        let edu_cess = (tax_book_profit + surcharge) * 0.03;
+        setValue("edu_cess_3", edu_cess);
+
+        let total_tax_payable = tax_book_profit + surcharge + edu_cess;
+        setValue("total_tax_payable", total_tax_payable);
+
+        let mat_credit = getValue("mat_credit");
+        let interest_234c = getValue("interest_234c");
+
+        let total_tax = total_tax_payable + mat_credit + interest_234c;
+        setValue("total_tax", total_tax);
+
+        // Assessment
+        let adv_tax = getValue("advance_tax");
+        let tds = getValue("tds");
+        let tcs = getValue("tcs");
+
+        let tax_on_assessment = adv_tax + tds + tcs;
+        setValue("tax_on_assessment", tax_on_assessment);
+
+        let refund = total_tax - tax_on_assessment;
+        setValue("refund", refund);
+    }
+
+    // Attach event listeners
+    fields.forEach(id => {
+        const element = document.getElementsByName(id)[0];
+        if (element) {
+            element.addEventListener("input", calculate);
+        }
+    });
+});