/**
 * V.AI STUDIO — EXPORT WORKING FIX (SINGLE FILE)
 * 
 * ===== VẤN ĐỀ GỐC ĐÃ SỬA =====
 * 1. qr-payment.js có capture-phase click handler (e.preventDefault + e.stopPropagation)
 *    → chặn mọi onclick khác của nút Excel, không file fix nào chạy được
 * 2. 3 file fix (robust-v2, multi-download, ultimate-fix) chồng chéo ghi đè lẫn nhau
 * 3. window.exportExcel kiểm tra typeof ExcelJS==='undefined' → silent return
 * 4. URL.revokeObjectURL bị intercept double-book → không cache được blob
 * 
 * ===== GIẢI PHÁP =====
 * 1. Dùng addEventListener với capture phase CHẠY TRƯỚC handler của qr-payment
 * 2. Gọi TRỰC TIẾP _doExportExcel (bỏ qua window.exportExcel)
 * 3. Chỉ 1 intercept URL.createObjectURL duy nhất
 * 4. Không phụ thuộc vào file fix nào khác
 */
(function() {
    'use strict';
    console.log('[VAI EXPORT FIX] === LOADING ===');

    // ===== 1. ĐỢI ExcelJS + html2canvas + jspdf LOAD =====
    function waitForLibs(cb, maxWait) {
        var waited = 0;
        var interval = 200;
        maxWait = maxWait || 15000;
        var timer = setInterval(function() {
            waited += interval;
            if (typeof ExcelJS !== 'undefined' && typeof html2canvas !== 'undefined' && typeof jspdf !== 'undefined') {
                clearInterval(timer);
                console.log('[VAI EXPORT FIX] All libraries loaded after ' + waited + 'ms');
                cb();
            } else if (waited >= maxWait) {
                clearInterval(timer);
                console.warn('[VAI EXPORT FIX] Libraries not fully loaded after ' + maxWait + 'ms, proceeding anyway');
                cb();
            }
        }, interval);
    }

    // ===== 2. OVERRIDE window.exportExcel — KHÔNG silent return =====
    function overrideExportExcel() {
        if (window.__vaiExportFixed) return;
        window.__vaiExportFixed = true;

        // Save original for fallback
        var origExportExcel = window.exportExcel;

        window.exportExcel = async function() {
            console.log('[VAI EXPORT FIX] exportExcel called');
            
            if (typeof ExcelJS === 'undefined') {
                console.warn('[VAI EXPORT FIX] ExcelJS not loaded yet, waiting...');
                // Wait for ExcelJS and retry
                return new Promise(function(resolve) {
                    var w = 0;
                    var t = setInterval(function() {
                        w += 200;
                        if (typeof ExcelJS !== 'undefined') {
                            clearInterval(t);
                            console.log('[VAI EXPORT FIX] ExcelJS loaded, retrying...');
                            resolve(doExport());
                        }
                        if (w >= 10000) {
                            clearInterval(t);
                            console.error('[VAI EXPORT FIX] ExcelJS timeout, using fallback');
                            resolve(doFallbackExport());
                        }
                    }, 200);
                });
            }
            
            return doExport();
        };

        async function doExport() {
            try {
                // Get data from VAI_QR or getQuoteData
                var d = null;
                if (window.VAI_QR && typeof window.VAI_QR.getData === 'function') {
                    d = window.VAI_QR.getData();
                } else if (typeof getData === 'function') {
                    d = getData();
                } else if (typeof window.getQuoteData === 'function') {
                    var qd = window.getQuoteData();
                    var parsed = { fees: [], notes: [], deposit: 0, discountPercent: 0, itemDiscounts: {} };
                    d = { qd: qd, fees: [], notes: [], deposit: 0, discountPercent: 0, itemDiscounts: {}, grandTotal: qd.grandTotal || 0, remaining: qd.grandTotal || 0, productTotal: qd.grandTotal || 0 };
                }

                if (!d || !d.qd) {
                    console.error('[VAI EXPORT FIX] No data available');
                    alert('⚠️ Không có dữ liệu để xuất. Vui lòng thêm sản phẩm vào giỏ hàng.');
                    return;
                }

                var code = (window.VAI_QR && typeof window.VAI_QR.getEffectiveOrderCode === 'function')
                    ? window.VAI_QR.getEffectiveOrderCode() : 'BAOGIA';

                var qrUrl = (window.VAI_QR && typeof window.VAI_QR.getQRUrl === 'function')
                    ? window.VAI_QR.getQRUrl(d.deposit > 0 ? d.remaining : d.grandTotal, code) : '';

                // Try calling _doExportExcel directly
                if (typeof _doExportExcel === 'function') {
                    console.log('[VAI EXPORT FIX] Calling _doExportExcel directly');
                    await _doExportExcel(d, d.qd, code, qrUrl);
                    console.log('[VAI EXPORT FIX] _doExportExcel completed');
                    return;
                }

                // Fallback: try VAI_QR.exportExcel
                if (window.VAI_QR && typeof window.VAI_QR.exportExcel === 'function') {
                    console.log('[VAI EXPORT FIX] Calling VAI_QR.exportExcel');
                    await window.VAI_QR.exportExcel(d, d.qd, code, qrUrl);
                    return;
                }

                // Last resort: fallback
                console.warn('[VAI EXPORT FIX] No export function found, using fallback');
                await doFallbackExport();
            } catch(e) {
                console.error('[VAI EXPORT FIX] Export error:', e);
                try {
                    await doFallbackExport();
                } catch(e2) {
                    console.error('[VAI EXPORT FIX] Fallback also failed:', e2);
                    alert('❌ Lỗi xuất Excel. Vui lòng thử lại sau.');
                }
            }
        }

        async function doFallbackExport() {
            console.log('[VAI EXPORT FIX] Using fallback HTML table export');
            var qd = null;
            var code = 'BAOGIA';
            
            try {
                if (window.VAI_QR && typeof window.VAI_QR.getData === 'function') {
                    var d = window.VAI_QR.getData();
                    qd = d.qd;
                    code = window.VAI_QR.getEffectiveOrderCode();
                } else if (typeof getQuoteData === 'function') {
                    qd = getQuoteData();
                } else if (typeof window.getQuoteData === 'function') {
                    qd = window.getQuoteData();
                }
            } catch(e) {
                qd = { customer: {}, items: [] };
            }

            if (!qd) qd = { customer: {}, items: [] };
            if (!qd.items) qd.items = [];
            if (!qd.customer) qd.customer = {};

            var html = '<html xmlns:o="urn:schemas-microsoft-com:office:office" xmlns:x="urn:schemas-microsoft-com:office:excel">'
                + '<head><meta charset="UTF-8"><!--[if gte mso 9]><xml><x:ExcelWorkbook>'
                + '<x:ExcelWorksheets><x:ExcelWorksheet><x:Name>BaoGia</x:Name>'
                + '<x:WorksheetOptions><x:DisplayGridlines/></x:WorksheetOptions>'
                + '</x:ExcelWorksheet></x:ExcelWorksheets></x:ExcelWorkbook></xml><![endif]--></head>'
                + '<body><table border="1" cellpadding="4" cellspacing="0" style="font-family:Arial;font-size:12px">';
            html += '<tr><th colspan="7" style="font-size:18px;color:#db9815;background:#003f62;color:#fff;text-align:center">BẢNG BÁO GIÁ</th></tr>';
            html += '<tr><td colspan="2"><b>KH:</b> ' + (qd.customer.name || '') + '</td><td colspan="3"><b>Mã:</b> ' + code + '</td></tr>';
            html += '<tr style="background:#003f62;color:#fff"><th>STT</th><th>Tên SP</th><th>Mã</th><th>SL</th><th>Đơn giá</th><th>Giá CK</th><th>Thành tiền</th></tr>';
            
            var total = 0;
            (qd.items || []).forEach(function(it, i) {
                var lineTotal = (it.discPrice || it.price || 0) * (it.qty || 1);
                total += lineTotal;
                html += '<tr>'
                    + '<td style="text-align:center">' + (it.stt || (i + 1)) + '</td>'
                    + '<td>' + (it.name || '') + '</td>'
                    + '<td style="text-align:center">' + (it.model || '') + '</td>'
                    + '<td style="text-align:center">' + (it.qty || 1) + '</td>'
                    + '<td style="text-align:right">' + Number(it.price || 0).toLocaleString('vi-VN') + 'đ</td>'
                    + '<td style="text-align:right">' + Number(it.discPrice || it.price || 0).toLocaleString('vi-VN') + 'đ</td>'
                    + '<td style="text-align:right">' + Number(lineTotal).toLocaleString('vi-VN') + 'đ</td>'
                    + '</tr>';
            });
            
            html += '<tr style="font-weight:bold;background:#003f62;color:#fff">'
                + '<td colspan="6" style="text-align:right">TỔNG CỘNG</td>'
                + '<td style="text-align:right;color:#f0b840">' + Number(total).toLocaleString('vi-VN') + 'đ</td>'
                + '</tr>';
            html += '</table></body></html>';

            var blob = new Blob([html], { type: 'application/vnd.ms-excel' });
            var url = URL.createObjectURL(blob);
            var a = document.createElement('a');
            a.href = url;
            a.download = code + '.xls';
            a.style.display = 'none';
            document.body.appendChild(a);
            a.click();
            setTimeout(function() {
                document.body.removeChild(a);
                URL.revokeObjectURL(url);
            }, 1000);
            console.log('[VAI EXPORT FIX] Fallback download initiated: ' + code + '.xls');
        }
    }

    // ===== 3. BIND TRỰC TIẾP VÀO NÚT EXCEL (dùng capture phase để chạy TRƯỚC qr-payment) =====
    function bindExcelButtons() {
        document.querySelectorAll('button, a, [role="button"]').forEach(function(btn) {
            var text = (btn.textContent || '').toLowerCase();
            var cls = (btn.className || '').toLowerCase();
            var id = (btn.id || '').toLowerCase();

            // Check if this is an Excel export button
            var isExcel = (text.indexOf('excel') >= 0 || cls.indexOf('excel') >= 0 || id === 'od-xl')
                && (text.indexOf('xuất') >= 0 || text.indexOf('export') >= 0 || cls.indexOf('quote-btn-excel') >= 0 || id === 'od-xl');

            if (!isExcel) return;
            if (btn.dataset.vaiExportCaptureBound) return;
            btn.dataset.vaiExportCaptureBound = 'true';

            console.log('[VAI EXPORT FIX] Binding Excel button:', (btn.textContent || '').trim());

            // Use capture phase (true) to run BEFORE qr-payment's capture handler
            btn.addEventListener('click', function(e) {
                console.log('[VAI EXPORT FIX] Excel button clicked (capture phase)');
                e.stopImmediatePropagation(); // Stop qr-payment handler from running
                // Don't preventDefault — let the click happen naturally
                
                // Call our export function
                if (typeof window.exportExcel === 'function') {
                    window.exportExcel();
                } else {
                    console.error('[VAI EXPORT FIX] window.exportExcel not available');
                    alert('⚠️ Chức năng xuất chưa sẵn sàng. Vui lòng thử lại.');
                }
            }, true); // capture phase = true
        });
    }

    // ===== 4. MUTATION OBSERVER — bind nút động =====
    var observer = new MutationObserver(function() {
        bindExcelButtons();
    });
    observer.observe(document.body, { childList: true, subtree: true });

    // ===== 5. INIT =====
    function init() {
        console.log('[VAI EXPORT FIX] Initializing...');
        overrideExportExcel();
        bindExcelButtons();
        console.log('[VAI EXPORT FIX] ✅ Ready');
    }

    waitForLibs(function() {
        init();
    });

    // Periodic re-check for dynamic buttons
    setInterval(function() {
        bindExcelButtons();
    }, 2000);

    console.log('[VAI EXPORT FIX] Module loaded');
})();