ns_erpnext_app/ns_app/public/js/customer_statements.js

// Customer Statements: generate printable, one-page-per-customer account
// statements formatted for a window envelope. Two entry points share the same
// generate/print helpers — a multi-select action on the Customer list and a
// single-customer button on the Customer form. Loaded globally so both the
// list view and the form can reach the shared `ns_statements` helpers.

frappe.provide("ns_statements");

// The Customer list button is registered separately in customer_list.js
// (a doctype_list_js) so it merges with — rather than overwrites — ERPNext's
// own listview_settings["Customer"]. Shared helpers live here on ns_statements.

// ── Entry point: Customer form ───────────────────────────────────────────────
frappe.ui.form.on("Customer", {
    refresh(frm) {
        if (frm.is_new()) return;
        frm.add_custom_button(__("Generate Statement"), () => {
            ns_statements.generate_for_customer(frm.doc.name);
        });
    }
});

// ── Shared: call the backend and open the printable document ─────────────────
ns_statements.run = function (customers, skip_late_fee) {
    frappe.call({
        method: "ns_app.api.statements.generate_statements",
        args: { customers, skip_late_fee: skip_late_fee ? 1 : 0 },
        freeze: true,
        freeze_message: __("Generating statements..."),
        callback(r) {
            if (!r.message || !r.message.html) return;
            ns_statements.open_print_window(r.message.html);
            const skipped = (r.message.skipped || []).length;
            if (skipped) {
                frappe.show_alert({
                    message: __("Skipped {0} customer(s) with no balance.", [skipped]),
                    indicator: "orange"
                });
            }
        }
    });
};

ns_statements.open_print_window = function (html) {
    const w = window.open("", "_blank");
    if (!w) {
        frappe.msgprint(__("Please allow pop-ups to view the statements."));
        return;
    }
    w.document.open();
    w.document.write(html);
    w.document.close();
};

// ── List flow: pick customers with overdue invoices, then generate ───────────
ns_statements.pick_and_generate = function () {
    frappe.call({
        method: "ns_app.api.statements.get_customers_with_overdue_invoices",
        freeze: true,
        freeze_message: __("Finding customers with overdue invoices..."),
        callback(r) {
            const rows = r.message || [];
            if (!rows.length) {
                frappe.msgprint({
                    title: __("No Overdue Customers"),
                    message: __("No customers currently have overdue invoices."),
                    indicator: "green"
                });
                return;
            }
            ns_statements._selection_dialog(rows);
        }
    });
};

ns_statements._selection_dialog = function (rows) {
    const uid = Date.now();
    const selected = new Set(rows.map(r => r.customer)); // default: all selected

    const body = rows.map(r => `
        <tr>
          <td class="text-center">
            <input type="checkbox" class="cust-check-${uid}"
                   data-name="${frappe.utils.escape_html(r.customer)}" checked>
          </td>
          <td>${frappe.utils.escape_html(r.customer_name || r.customer)}</td>
          <td class="text-center">${r.overdue_count}</td>
          <td class="text-center">${r.max_days_overdue}</td>
          <td class="text-right">${format_currency(r.total_outstanding)}</td>
        </tr>`).join("");

    const dialog = new frappe.ui.Dialog({
        title: __("Generate Customer Statements"),
        size: "large",
        fields: [
            {
                fieldtype: "HTML",
                fieldname: "selector",
                options: `
                    <div style="max-height:45vh; overflow:auto;">
                      <table class="table table-bordered table-sm" style="font-size:13px; margin:0;">
                        <thead style="position:sticky; top:0; background:#f5f5f5;">
                          <tr>
                            <th style="width:36px;">
                              <input type="checkbox" id="sel_all_${uid}" title="${__("Select all")}" checked>
                            </th>
                            <th>${__("Customer")}</th>
                            <th class="text-center">${__("Overdue Invoices")}</th>
                            <th class="text-center">${__("Max Days Overdue")}</th>
                            <th class="text-right">${__("Total Outstanding")}</th>
                          </tr>
                        </thead>
                        <tbody id="sel_body_${uid}">${body}</tbody>
                      </table>
                    </div>
                    <div id="sel_count_${uid}" style="margin-top:8px; font-weight:bold;"></div>`
            },
            {
                fieldtype: "Check",
                fieldname: "generate_late_fee",
                label: __("Generate late payment fee"),
                default: 1,
                description: __("Bills a late-fee invoice (once per customer this month) for overdue balances.")
            }
        ],
        primary_action_label: __("Generate Statements"),
        primary_action() {
            const customers = [...selected];
            if (!customers.length) {
                frappe.msgprint(__("Select at least one customer."));
                return;
            }
            const gen_fee = dialog.get_value("generate_late_fee");
            const proceed = () => {
                dialog.hide();
                ns_statements.run(customers, !gen_fee);
            };
            if (gen_fee) {
                frappe.confirm(
                    __("Generate statements for {0} customer(s)? A late-fee invoice will be raised (once per customer this month) for any overdue balances.", [customers.length]),
                    proceed
                );
            } else {
                proceed();
            }
        }
    });

    dialog.show();

    const update_count = () => {
        const el = document.getElementById(`sel_count_${uid}`);
        if (el) el.innerText = __("{0} of {1} selected", [selected.size, rows.length]);
    };
    update_count();

    dialog.$wrapper.on("change", `.cust-check-${uid}`, function () {
        if (this.checked) selected.add(this.dataset.name);
        else selected.delete(this.dataset.name);
        const all = dialog.$wrapper[0].querySelectorAll(`.cust-check-${uid}`);
        const selAll = document.getElementById(`sel_all_${uid}`);
        if (selAll) selAll.checked = [...all].every(c => c.checked);
        update_count();
    });

    dialog.$wrapper.on("change", `#sel_all_${uid}`, function () {
        dialog.$wrapper[0].querySelectorAll(`.cust-check-${uid}`).forEach(cb => {
            cb.checked = this.checked;
            if (this.checked) selected.add(cb.dataset.name);
            else selected.delete(cb.dataset.name);
        });
        update_count();
    });
};

// ── Form flow: single customer, with the same fee toggle ─────────────────────
ns_statements.generate_for_customer = function (customer) {
    const d = new frappe.ui.Dialog({
        title: __("Generate Statement"),
        fields: [
            {
                fieldtype: "HTML",
                options: `<p>${__("Generate an account statement for <b>{0}</b>.", [frappe.utils.escape_html(customer)])}</p>`
            },
            {
                fieldtype: "Check",
                fieldname: "generate_late_fee",
                label: __("Generate late payment fee"),
                default: 1,
                description: __("Bills a late-fee invoice (once this month) for overdue balances.")
            }
        ],
        primary_action_label: __("Generate"),
        primary_action(values) {
            d.hide();
            ns_statements.run([customer], !values.generate_late_fee);
        }
    });
    d.show();
};