document.addEventListener("DOMContentLoaded", function () {
    function getValue(id) {
        var el = document.getElementsByName(id)[0];
        return el ? parseFloat(el.value) || 0 : 0;
    }

    function setValue(id, val) {
        var el = document.getElementsByName(id)[0];
        if (el) el.value = Number(val).toFixed(2);
    }

    window.calculate = function () {
        // --- BASIC INPUTS ---
        var gross_total_income = getValue("gross_total_income");
        var disallowance_14a = getValue("disallowance_14a");
        var disallowance_37 = getValue("disallowance_37");

        // -- total gross income --
        var gross_total = gross_total_income + disallowance_37 + disallowance_14a;
        setValue("gti_as_per_ao", gross_total);

        // --- DEDUCTIONS ---
        var d80_business = getValue("deduction_80ia_business");
        var d80_misc = getValue("deduction_80ia_misc");
        var d80_other = getValue("deduction_80ia_other");
        var d80_sec37 = getValue("deduction_sec37_disallowance");

        // -- TAX A CALCULATIONS --
        var per_a = getValue("per_a");
        var tax_a = getValue("tax_a");
        var per_surcharge_a = getValue("per_surcharge_a");
        var surcharge_a = getValue("surcharge_a");
        var per_cess_a = getValue("per_cess_a");
        var edu_cess_a = getValue("edu_cess_a");

        // -- TAX b CALCULATIONS --

        var tax_book_profit = getValue("tax_book_profit");
        console.log(tax_book_profit);

        var per_surcharge_b = getValue("per_surcharge_b");
        var surcharge_b = getValue("surcharge_b");
        var per_cess_b = getValue("per_cess_b");
        var edu_cess_b = getValue("edu_cess_b");

        var deduction = d80_business + d80_misc + d80_other + d80_sec37 - 1.35;

        var deduction_80g = getValue("deduction_80g");

        // --- NET TAXABLE INCOME ---
        var net_taxable_income = gross_total - deduction - deduction_80g;
        setValue("net_taxable_income", net_taxable_income);

        // --- TAX (A)% AMOUNT ---
        var tax_a = net_taxable_income * (per_a / 100);
        setValue("tax_a", tax_a);

        // --- SURCHARGE (A)% AMOUNT ---
        var surcharge_a = tax_a * (per_surcharge_a / 100);
        setValue("surcharge_a", surcharge_a);

        // --- CESS (A)% AMOUNT ---
        var edu_cess_a = (surcharge_a + tax_a) * (per_cess_a / 100);
        setValue("edu_cess_a", edu_cess_a);

        //SUM OF (A)%
        var sum_of_a = tax_a + surcharge_a + edu_cess_a;

        setValue("sum_of_a", sum_of_a);

        //-----------------------------------------------------------------------------------------------------------
        //-----------------------------------------------------------------------------------------------------------

        // --- SURCHARGE (B)% AMOUNT ---
        var surcharge_b = tax_book_profit * (per_surcharge_b / 100);
        setValue("surcharge_b", surcharge_b);

        // --- CESS (B)% AMOUNT ---
        var edu_cess_b = (surcharge_b + tax_book_profit) * (per_cess_b / 100);
        setValue("edu_cess_b", edu_cess_b);

        //SUM OF (B)%
        var sum_of_b = tax_book_profit + surcharge_b + edu_cess_b;

        setValue("sum_of_b", sum_of_b);

        // --- TAX PAYABLE (18.5%) ---
        var tax185 = getValue("tax_book_profit_18_5");

        // --- Education Cess 3% ---
        var tax_payable = tax_a > tax_book_profit ? tax_a : tax_book_profit;
        setValue("tax_payable", tax_payable);

        // --- SURCHARGE ---
        var percent = getValue("persentage");
        var surcharge = tax_payable * (percent / 100);
        setValue("surcharge", surcharge);

        // --- EDUCATION CESS ---
        var per_cess = getValue("persentage_cess");
        var edu_cess = (tax_payable + surcharge) * (per_cess / 100);
        setValue("edu_cess", edu_cess);

        // --- total tax payable ---
        var total_tax_payable = sum_of_a > sum_of_b ? sum_of_a : sum_of_b;
        setValue("total_tax_payable", total_tax_payable);

        // // --- mat_credit_created --- new
        // setValue("mat_credit_created", Math.max(tax185 - total_tax_payable, 0));
        // // --- mat credit_utilized --- new
        // setValue("mat_credit_utilized", Math.max(total_tax_payable - tax185, 0));

        // --- MAT credit and utilized ---
        var a = sum_of_a;
        var b = sum_of_b;
        var result = 0;
        var zero = 0;
        if (b > a) {
            result = b - a;
            setValue("mat_credit_created", result);
            setValue("mat_credit_utilized", zero);
        }

        if (a > b) {
            result = a - b;
            setValue("mat_credit_utilized", result);
            setValue("mat_credit_created", zero);
        }

        // --- FINAL TAX ---
        var mat_credit_uti = getValue("mat_credit_utilized");
        var interest_234c = getValue("interest_234c");

        // var total_tax = total_tax_payable + mat_credit + interest_234c;
        var total_tax = total_tax_payable + interest_234c - mat_credit_uti;
        setValue("total_tax", total_tax);

        // --- ASSESSMENT ---
        var adv_tax = getValue("advance_tax");
        var tds = getValue("tds");
        var tcs = getValue("tcs");
        var tax_on_regular_assessment = getValue("tax_on_assessment");

        var all_tax = adv_tax + tds + tcs + tax_on_regular_assessment;

        var refund = total_tax - all_tax;
        setValue("refund", refund);
    };
});