// helper: format currency (Indonesia style) - untuk fallback client-side rendering
function fmtMoney(n) {
    n = Number(n) || 0;
    var parts = n.toFixed(2).split('.');
    parts[0] = parts[0].replace(/\B(?=(\d{3})+(?!\d))/g, ".");
    return parts[0] + ',' + parts[1];
}

// Function: build HTML client-side (same logic as template) - dipakai ketika doc belum disimpan
function build_message_html_client(doc, ref_doc) {
    var amount = Number(doc.grand_total || doc.amount || 0);
    var netto = amount ? (amount / 1.11) : 0;
    var ppn = amount - netto;

    var qty = 0;
    if (ref_doc) {
        qty = Number(ref_doc.total_qty || 0);
        if (!qty && ref_doc.items) {
            for (var i = 0; i < ref_doc.items.length; i++) {
                qty += Number(ref_doc.items[i].qty || 0);
            }
        }
    }
    if (!qty) qty = 1;

    var per_unit = netto / qty;

    var html = '';
    html += '<div style="font-family: Arial, sans-serif; font-size: 13px; line-height: 1.6;">';
    html += '<table border="1" cellspacing="0" cellpadding="6" width="100%" style="border-collapse: collapse;">';
    html += '<thead style="background:#f2f2f2;"><tr><th style="width:5%">No</th><th style="width:55%">Nama Barang</th><th style="width:10%;text-align:center">Banyaknya</th><th style="text-align:right;width:15%">Harga Satuan</th><th style="text-align:right;width:15%">Jumlah Satuan</th></tr></thead>';
    html += '<tbody>';
    html += '<tr>';
    html += '<td style="text-align:center;">1</td>';
    var name = (ref_doc && ref_doc.items && ref_doc.items.length>0) ? (ref_doc.items[0].item_name || "Nama Barang / Uraian") : "Nama Barang / Uraian";
    html += '<td>' + name + '</td>';
    html += '<td style="text-align:center;">' + (qty.toFixed(2)) + '</td>';
    html += '<td style="text-align:right;">Rp ' + fmtMoney(per_unit) + '</td>';
    html += '<td style="text-align:right;">Rp ' + fmtMoney(netto) + '</td>';
    html += '</tr>';

    html += '<tr><td colspan="4" style="text-align:right;">Diskon</td><td style="text-align:right;">Rp ' + fmtMoney(0) + '</td></tr>';
    html += '<tr><td colspan="4" style="text-align:right;">PPN 11%</td><td style="text-align:right;">Rp ' + fmtMoney(ppn) + '</td></tr>';
    html += '<tr><td colspan="4" style="text-align:right;font-weight:bold;">Total</td><td style="text-align:right;font-weight:bold;">Rp ' + fmtMoney(amount) + '</td></tr>';

    html += '</tbody></table>';

    html += '<p style="margin-top:10px;">Terbilang : <b>' + ( (typeof frappe !== 'undefined' && frappe.utils && frappe.utils.money_in_words) ? frappe.utils.money_in_words(amount, (doc.currency || "IDR")) : "") + '</b></p>';

    html += '<p style="margin-top:30px; text-align:right;">Jakarta, ' + ((doc.transaction_date) ? doc.transaction_date : ( (typeof frappe !== 'undefined' && frappe.utils && frappe.utils.nowdate) ? frappe.utils.nowdate() : "" )) + '<br>Hormat kami,</p>';

    html += '</div>';
    return html;
}

// Function: update message - uses server render if docname exists, otherwise client-side render
function update_message(frm) {
    // If there's a reference document, fetch it (for client-side rendering)
    var ref_doctype = frm.doc.reference_doctype;
    var ref_name = frm.doc.reference_name;

    var do_server_render = !!frm.doc.name; // prefer server render when doc saved (has name)

    if (ref_doctype && ref_name) {
        frappe.call({
            method: "frappe.client.get",
            args: { doctype: ref_doctype, name: ref_name },
            callback: function(r) {
                var ref_doc = r.message || null;
                if (do_server_render) {
                    // server render (uses api.get_payment_message)
                    frappe.call({
                        method: "editor_override.api.get_payment_message",
                        args: { docname: frm.doc.name },
                        callback: function(res) {
                            if (res.message) {
                                frm.set_value("message", res.message);
                                frm.refresh_field("message");
                            }
                        }
                    });
                } else {
                    // client-side render for unsaved doc
                    var html = build_message_html_client(frm.doc, ref_doc);
                    frm.set_value("message", html);
                    frm.refresh_field("message");
                }
            }
        });
    } else {
        // no reference doc
        if (do_server_render) {
            frappe.call({
                method: "editor_override.api.get_payment_message",
                args: { docname: frm.doc.name },
                callback: function(res) {
                    if (res.message) {
                        frm.set_value("message", res.message);
                        frm.refresh_field("message");
                    }
                }
            });
        } else {
            var html = build_message_html_client(frm.doc, null);
            frm.set_value("message", html);
            frm.refresh_field("message");
        }
    }
}

// ===========================
// Payment Term logic (existing) + tie to update_message
// ===========================
frappe.ui.form.on("Payment Request", {
    onload: function(frm) {
        // set default or initial behaviours if needed
        // e.g. df property toggles, default percent, etc. (adapt from your original code)
        if (!frm.doc.custom_payment_term_percentage) {
            frm.set_value("custom_payment_term_percentage", 100);
        }
    },

    refresh: function(frm) {
        // always update message UI on refresh (safe)
        update_message(frm);
    },

    reference_name: function(frm) {
        // when reference changes, fetch base amount and refresh message
        if (frm.doc.reference_doctype === "Sales Order" && frm.doc.reference_name) {
            // fetch SO grand_total and set as amount (default 100% portion)
            frappe.call({
                method: "frappe.client.get",
                args: { doctype: "Sales Order", name: frm.doc.reference_name },
                callback: function(r) {
                    if (r.message && r.message.grand_total) {
                        // if no custom percent set, set amount to full SO
                        var portion = frm.doc.custom_payment_term_percentage || 100;
                        var final_amount = (r.message.grand_total * portion) / 100;
                        frm.set_value("grand_total", final_amount);
                        frm.refresh_field("grand_total");
                        // now update message
                        update_message(frm);
                    }
                }
            });
        } else {
            update_message(frm);
        }
    },

    custom_payment_term: function(frm) {
        var value = frm.doc.custom_payment_term;
        if (!value) {
            frm.set_value("custom_payment_term_percentage", 100);
            // get original amount from SO and refresh message
            if (frm.doc.reference_doctype === "Sales Order" && frm.doc.reference_name) {
                frappe.call({
                    method: "frappe.client.get",
                    args: { doctype: "Sales Order", name: frm.doc.reference_name },
                    callback: function(r) {
                        if (r.message && r.message.grand_total) {
                            frm.set_value("grand_total", r.message.grand_total);
                            frm.refresh_field("grand_total");
                            update_message(frm);
                        }
                    }
                });
            } else {
                update_message(frm);
            }
        } else {
            // fetch selected Payment Term invoice_portion
            frappe.call({
                method: "frappe.client.get",
                args: {
                    doctype: "Payment Term",
                    name: value
                },
                callback: function(r) {
                    if (r.message && r.message.invoice_portion !== undefined) {
                        var portion = r.message.invoice_portion;
                        frm.set_value("custom_payment_term_percentage", portion);
                        // calc final amount based on sales order base
                        if (frm.doc.reference_doctype === "Sales Order" && frm.doc.reference_name) {
                            frappe.call({
                                method: "frappe.client.get",
                                args: { doctype: "Sales Order", name: frm.doc.reference_name },
                                callback: function(rr) {
                                    if (rr.message && rr.message.grand_total) {
                                        var final_amount = (rr.message.grand_total * portion) / 100;
                                        frm.set_value("grand_total", final_amount);
                                        frm.refresh_field("grand_total");
                                        // Immediately update message to reflect new grand_total
                                        update_message(frm);
                                    }
                                }
                            });
                        } else {
                            update_message(frm);
                        }
                    }
                }
            });
        }
    },

    // in case grand_total is edited manually
    grand_total: function(frm) {
        update_message(frm);
    }

});