/**
 * V.AI STUDIO - Excel Export Fix Ultimate v2.0
 * ============================================
 * FIX 100%: Multi-download Excel for Quote & Order modals
 * 
 * Key fixes:
 * 1. Global blob URL registry - prevents premature URL.revokeObjectURL
 * 2. Creates fresh blob for each download
 * 3. Proper cleanup on page unload only
 * 4. Click protection to prevent double-clicks
 */
(function(){
'use strict';

// ===== GLOBAL STATE =====
window.__VAI_EXCEL_FIX = window.__VAI_EXCEL_FIX || {
    blobRegistry: [],
    isUnloading: false
};

var g = window.__VAI_EXCEL_FIX;

// ===== CLEANUP ON UNLOAD =====
function cleanupAllBlobs() {
    g.isUnloading = true;
    g.blobRegistry.forEach(function(entry) {
        if (!entry.revoked && entry.url) {
            try { URL.revokeObjectURL(entry.url); entry.revoked = true; } catch(e) {}
        }
    });
    g.blobRegistry = [];
}

window.addEventListener('pagehide', cleanupAllBlobs);
window.addEventListener('beforeunload', cleanupAllBlobs);
window.addEventListener('unload', cleanupAllBlobs);

// ===== PATCH URL.revokeObjectURL - CRITICAL =====
if (!window.__VAI_REVOKE_PATCHED) {
    var originalRevoke = URL.revokeObjectURL;
    URL.revokeObjectURL = function(url) {
        // Only revoke on unload or non-blob URLs
        if (g.isUnloading || !url || typeof url !== 'string' || !url.startsWith('blob:')) {
            return originalRevoke.call(this, url);
        }
        // Register but DON'T revoke - this is the key fix for multi-download
        var exists = g.blobRegistry.find(function(e) { return e.url === url; });
        if (!exists) {
            g.blobRegistry.push({ url: url, revoked: false, created: Date.now() });
        }
        return undefined;
    };
    window.__VAI_REVOKE_PATCHED = true;
}

// ===== UTILITIES =====
function fmt(n) {
    if (!n || isNaN(n)) return '0đ';
    return Number(n).toLocaleString('vi-VN') + 'đ';
}

function stripDiacritics(s) {
    return s.normalize('NFD').replace(/[\u0300-\u036f]/g, '').replace(/[Đđ]/g, 'D');
}

function generateOrderCode(name) {
    var d = new Date();
    var dd = String(d.getDate()).padStart(2, '0');
    var mm = String(d.getMonth() + 1).padStart(2, '0');
    var yy = String(d.getFullYear()).slice(-2);
    var ini = '';
    if (name && name.trim()) {
        name.trim().split(/\s+/).forEach(function(w) {
            if (w) {
                var ch = stripDiacritics(w.charAt(0)).toUpperCase();
                if (/[A-Z]/.test(ch)) {
                    ini += ch;
                }
            }
        });
    }
    return 'VAS' + (ini || 'X') + dd + mm + yy;
}

// ===== BUTTON STATE =====
function setBtnState(btn, exporting) {
    if (!btn) return;
    if (exporting) {
        btn.disabled = true;
        btn.dataset.vaiExporting = '1';
        btn.dataset.vaiOrigHTML = btn.innerHTML;
        btn.innerHTML = '<span style="opacity:0.7">⏳ Đang xuất...</span>';
    } else {
        btn.disabled = false;
        btn.dataset.vaiExporting = '0';
        if (btn.dataset.vaiOrigHTML) {
            btn.innerHTML = btn.dataset.vaiOrigHTML;
        }
    }
}

// ===== CREATE DOWNLOAD =====
function downloadBlob(blob, filename) {
    var url = URL.createObjectURL(blob);
    g.blobRegistry.push({ url: url, revoked: false });
    
    var a = document.createElement('a');
    a.href = url;
    a.download = filename;
    a.style.cssText = 'position:fixed;left:-10000px;top:-10000px;width:1px;height:1px;';
    document.body.appendChild(a);
    a.click();
    
    setTimeout(function() {
        try { document.body.removeChild(a); } catch(e) {}
    }, 100);
}

// ===== GET QUOTE DATA FROM MODAL =====
function getQuoteData() {
    var data = {
        customer: { name: '', phone: '', email: '', addr: '', date: new Date().toLocaleDateString('vi-VN') },
        items: [],
        grandTotal: 0
    };
    
    // Get cart data
    var cart = window.cart || [];
    var products = window.D || [];
    
    cart.forEach(function(item, i) {
        var product = products[item.idx] || (products.find ? products.find(function(p) { return p.id === item.id; }) : null);
        var price = item.priceNum || item.price || (product ? product.price : 0) || 0;
        data.items.push({
            stt: i + 1,
            image: product ? product.img : '',
            name: product ? (product.name || product.n || '') : (item.name || ''),
            model: product ? (product.sku || product.mod || '') : (item.sku || item.model || ''),
            specs: product ? (product.info || product.desc || '') : '',
            qty: item.qty || 1,
            price: price,
            discPrice: price,
            total: (item.qty || 1) * price,
            note: ''
        });
    });
    
    // Get customer info from modal
    var nameSelectors = ['#quoteName', '#quoteCustomerName', '#checkoutName'];
    for (var j = 0; j < nameSelectors.length; j++) {
        var el = document.querySelector(nameSelectors[j]);
        if (el && el.value && el.value.trim()) {
            data.customer.name = el.value.trim();
            break;
        }
    }
    
    var phoneEl = document.querySelector('#quotePhone, #checkoutPhone');
    if (phoneEl && phoneEl.value) data.customer.phone = phoneEl.value.trim();
    
    var emailEl = document.querySelector('#quoteEmail');
    if (emailEl && emailEl.value) data.customer.email = emailEl.value.trim();
    
    var addrEl = document.querySelector('#quoteAddr, #checkoutAddr');
    if (addrEl && addrEl.value) data.customer.addr = addrEl.value.trim();
    
    data.grandTotal = data.items.reduce(function(s, i) { return s + (i.total || 0); }, 0);
    return data;
}

// ===== EXPORT QUOTE EXCEL =====
async function exportQuoteExcel(quoteData, code) {
    if (typeof ExcelJS === 'undefined') {
        if (typeof showToast === 'function') showToast('⚠️ Chưa có thư viện ExcelJS');
        return false;
    }
    
    try {
        var wb = new ExcelJS.Workbook();
        var ws = wb.addWorksheet('Báo giá');
        ws.views = [{ showGridLines: false }];
        ws.columns = [
            { width: 5 }, { width: 11 }, { width: 28 },
            { width: 13 }, { width: 20 }, { width: 6 },
            { width: 13 }, { width: 13 }, { width: 15 }, { width: 14 }
        ];
        
        ws.mergeCells('A3:J3');
        ws.getCell('A3').value = 'BẢNG BÁO GIÁ';
        ws.getCell('A3').font = { bold: true, size: 18, color: { argb: 'FFDB9815' } };
        ws.getCell('A3').alignment = { horizontal: 'center' };
        
        ws.getCell('A5').value = 'Khách hàng:';
        ws.mergeCells('B5:E5');
        ws.getCell('B5').value = quoteData.customer?.name || '';
        
        ws.getCell('H5').value = 'Mã đơn:';
        ws.mergeCells('I5:J5');
        ws.getCell('I5').value = code;
        
        ws.getCell('A6').value = 'SĐT:';
        ws.mergeCells('B6:E6');
        ws.getCell('B6').value = quoteData.customer?.phone || '';
        
        ws.getCell('H6').value = 'Ngày:';
        ws.mergeCells('I6:J6');
        ws.getCell('I6').value = quoteData.customer?.date || '';
        
        ws.getCell('A7').value = 'Email:';
        ws.mergeCells('B7:E7');
        ws.getCell('B7').value = quoteData.customer?.email || '';
        
        ws.getCell('A8').value = 'Địa chỉ:';
        ws.mergeCells('B8:J8');
        ws.getCell('B8').value = quoteData.customer?.addr || '';
        
        var hr = ws.getRow(10);
        ['STT', 'Hình', 'Tên sản phẩm', 'Mã SP', 'Thông tin', 'SL', 'Đơn giá', 'Giá CK', 'Thành tiền', 'Ghi chú'].forEach(function(h, i) {
            var c = hr.getCell(i + 1);
            c.value = h;
            c.font = { bold: true, color: { argb: 'FFFFFFFF' } };
            c.fill = { type: 'pattern', pattern: 'solid', fgColor: { argb: 'FF003F62' } };
        });
        
        var cr = 11, firstRow = cr;
        (quoteData.items || []).forEach(function(it, i) {
            var row = ws.getRow(cr);
            row.height = 50;
            var bg = i % 2 === 0 ? 'FFF8FAFC' : 'FFFFFFFF';
            
            row.getCell(1).value = it.stt || i + 1;
            row.getCell(3).value = it.name || '';
            row.getCell(3).font = { bold: true, size: 9 };
            row.getCell(4).value = it.model || '';
            row.getCell(5).value = it.specs || '';
            row.getCell(5).font = { size: 8, color: { argb: 'FF64748B' } };
            row.getCell(6).value = Number(it.qty || 1);
            row.getCell(6).numFmt = '#,##0';
            row.getCell(7).value = Number(it.price || 0);
            row.getCell(7).numFmt = '#,##0"đ"';
            row.getCell(8).value = Number(it.discPrice || it.price || 0);
            row.getCell(8).numFmt = '#,##0"đ"';
            if ((it.price || 0) > (it.discPrice || 0)) {
                row.getCell(8).font = { bold: true, color: { argb: 'FFDC3545' } };
            }
            row.getCell(9).value = Number(it.total || 0);
            row.getCell(9).numFmt = '#,##0"đ"';
            row.getCell(9).font = { bold: true };
            row.getCell(10).value = it.note || '';
            
            cr++;
        });
        
        ws.getRow(cr).height = 28;
        ws.mergeCells(cr, 1, cr, 5);
        ws.getCell('A' + cr).value = 'TỔNG CỘNG';
        ws.getCell('A' + cr).font = { bold: true, size: 13, color: { argb: 'FFFFFFFF' } };
        ws.getCell('A' + cr).fill = { type: 'pattern', pattern: 'solid', fgColor: { argb: 'FF003F62' } };
        ws.getCell('E' + cr).value = { formula: 'SUM(I' + firstRow + ':I' + (cr - 1) + ')', result: Number(quoteData.grandTotal || 0) };
        ws.getCell('E' + cr).numFmt = '#,##0"đ"';
        ws.getCell('E' + cr).font = { bold: true, size: 14, color: { argb: 'FFF0B840' } };
        
        wb.calcProperties.fullCalcOnLoad = true;
        
        var buf = await wb.xlsx.writeBuffer();
        var blob = new Blob([buf], { type: 'application/vnd.openxmlformats-officedocument.spreadsheetml.sheet' });
        
        downloadBlob(blob, code + '.xlsx');
        return true;
        
    } catch (err) {
        console.error('[VAI Excel Fix] exportQuoteExcel error:', err);
        alert('❌ Lỗi: ' + err.message);
        return false;
    }
}

// ===== EXPORT DELIVERY EXCEL =====
async function exportDeliveryExcel(quoteData, code) {
    if (typeof ExcelJS === 'undefined') {
        if (typeof showToast === 'function') showToast('⚠️ Chưa có thư viện ExcelJS');
        return false;
    }
    
    try {
        var wb = new ExcelJS.Workbook();
        var ws = wb.addWorksheet('Giao hàng');
        ws.views = [{ showGridLines: false }];
        ws.columns = [
            { width: 5 }, { width: 34 }, { width: 14 }, { width: 8 }, { width: 20 }
        ];
        
        ws.mergeCells('A1:E1');
        ws.getCell('A1').value = 'PHIẾU GIAO HÀNG';
        ws.getCell('A1').font = { bold: true, size: 16, color: { argb: 'FF003F62' } };
        ws.getCell('A1').alignment = { horizontal: 'center' };
        
        ws.getCell('A2').value = 'KH: ' + (quoteData.customer?.name || '');
        ws.getCell('D2').value = 'Mã: ' + code;
        ws.getCell('A3').value = 'SĐT: ' + (quoteData.customer?.phone || '');
        ws.getCell('D3').value = 'Ngày: ' + (quoteData.customer?.date || '');
        ws.getCell('A4').value = 'Địa chỉ: ' + (quoteData.customer?.addr || '');
        
        var hr = ws.getRow(6);
        ['STT', 'Tên sản phẩm', 'Mã SP', 'SL', 'Ghi chú'].forEach(function(h, i) {
            var c = hr.getCell(i + 1);
            c.value = h;
            c.font = { bold: true, color: { argb: 'FFFFFFFF' } };
            c.fill = { type: 'pattern', pattern: 'solid', fgColor: { argb: 'FF003F62' } };
        });
        
        var cr = 7, totalQty = 0;
        (quoteData.items || []).forEach(function(it, i) {
            var row = ws.getRow(cr);
            row.height = 20;
            row.getCell(1).value = it.stt || i + 1;
            row.getCell(2).value = it.name || '';
            row.getCell(3).value = it.model || '';
            row.getCell(4).value = it.qty || 1;
            row.getCell(5).value = it.note || '';
            totalQty += Number(it.qty || 1);
            cr++;
        });
        
        ws.mergeCells(cr, 1, cr, 3);
        ws.getCell('A' + cr).value = 'TỔNG CỘNG SỐ LƯỢNG';
        ws.getCell('D' + cr).value = totalQty;
        
        var buf = await wb.xlsx.writeBuffer();
        var blob = new Blob([buf], { type: 'application/vnd.openxmlformats-officedocument.spreadsheetml.sheet' });
        
        downloadBlob(blob, 'GH-' + code + '.xlsx');
        return true;
        
    } catch (err) {
        console.error('[VAI Excel Fix] exportDeliveryExcel error:', err);
        alert('❌ Lỗi: ' + err.message);
        return false;
    }
}

// ===== CLICK HANDLER =====
function handleExportClick(e) {
    var btn = e.target.closest('button, a');
    if (!btn) return;
    
    var txt = (btn.textContent || '').toLowerCase();
    
    // Quote Excel - "Xuất Excel" button in quote modal
    if (txt.includes('excel') && !txt.includes('giao hàng') && !txt.includes('gh-') && !txt.includes('giao')) {
        e.preventDefault();
        e.stopPropagation();
        
        if (btn.dataset.vaiExporting === '1') return;
        setBtnState(btn, true);
        
        var qd = getQuoteData();
        var code = generateOrderCode(qd.customer?.name || '');
        
        exportQuoteExcel(qd, code).then(function(success) {
            setBtnState(btn, false);
            if (success && typeof showToast === 'function') {
                showToast('✅ Excel báo giá tải thành công!');
            }
        });
        
        return false;
    }
    
    // Delivery Excel - "GH Excel" button in order modal
    if ((txt.includes('gh') || txt.includes('giao hàng')) && txt.includes('excel')) {
        e.preventDefault();
        e.stopPropagation();
        
        if (btn.dataset.vaiExporting === '1') return;
        setBtnState(btn, true);
        
        // Check for order modal data
        var order = window.VAI_CURRENT_ORDER;
        var exportData, orderCode;
        
        if (order && order.items) {
            // From order modal
            exportData = {
                customer: { name: order.customer || '', phone: order.phone || '', addr: order.addr || '', date: order.date || '' },
                items: (order.items || []).map(function(it, i) {
                    return {
                        stt: i + 1,
                        name: it.name || '',
                        model: it.model || '',
                        qty: it.qty || 1,
                        note: it.note || '',
                        specs: it.specs || '',
                        price: it.price || 0,
                        discPrice: it.discPrice || it.price || 0,
                        total: it.total || 0
                    };
                }),
                grandTotal: order.grandTotal || 0
            };
            orderCode = order.code || generateOrderCode(order.customer || '');
        } else {
            // From cart
            exportData = getQuoteData();
            orderCode = generateOrderCode(exportData.customer?.name || '');
        }
        
        exportDeliveryExcel(exportData, orderCode).then(function(success) {
            setBtnState(btn, false);
            if (success && typeof showToast === 'function') {
                showToast('✅ Excel giao hàng tải thành công!');
            }
        });
        
        return false;
    }
}

// ===== INIT =====
function init() {
    // Remove any existing handler to avoid duplicates
    document.removeEventListener('click', handleExportClick, true);
    // Add click handler
    document.addEventListener('click', handleExportClick, true);
    console.log('[VAI Excel Fix v2.0] Loaded - Multi-download enabled');
}

// Run on DOM ready
if (document.readyState === 'loading') {
    document.addEventListener('DOMContentLoaded', init);
} else {
    init();
}

// Also run after delays for dynamic content
setTimeout(init, 2000);
setTimeout(init, 5000);

// Export for global use
window.VAI_EXCEL_FIX = {
    init: init,
    exportQuoteExcel: exportQuoteExcel,
    exportDeliveryExcel: exportDeliveryExcel,
    generateOrderCode: generateOrderCode,
    getQuoteData: getQuoteData
};

})();