(function ($) {
    'use strict';

    $(document).ready(function () {

        var $uploadWrap = $('.studiou-fpp-upload-wrap');
        if (!$uploadWrap.length) {
            return;
        }

        var productId = $uploadWrap.data('product-id');
        var maxFileSize = parseInt($uploadWrap.data('max-file-size'), 10) || 50;
        var chunkSize = parseInt(studiouWcfppFront.chunkSize, 10) || 1048576;
        var uploadedAttachmentId = null;
        var uploadedFileRecordId = null;
        var isUploading = false;
        var originalGalleryImages = {};

        // Upload area elements
        var $dropzone = $uploadWrap.find('#studiou-fpp-dropzone');
        var $fileInput = $uploadWrap.find('#studiou-fpp-file-input');
        var $progress = $uploadWrap.find('.studiou-fpp-progress');
        var $progressFill = $uploadWrap.find('.studiou-fpp-progress-fill');
        var $progressText = $uploadWrap.find('.studiou-fpp-progress-text');
        var $preview = $uploadWrap.find('.studiou-fpp-preview');
        var $previewImg = $preview.find('img');
        var $previewName = $uploadWrap.find('.studiou-fpp-preview-name');
        var $removeBtn = $uploadWrap.find('.studiou-fpp-remove-file');
        var $messages = $uploadWrap.find('.studiou-fpp-messages');

        // ==========================================
        // Restore session state on page load
        // ==========================================
        if (typeof studiouWcfppSession !== 'undefined' && studiouWcfppSession.attachment_id) {
            uploadedAttachmentId = studiouWcfppSession.attachment_id;
            uploadedFileRecordId = studiouWcfppSession.file_record_id;
            showPreview(studiouWcfppSession.thumbnail_url, studiouWcfppSession.file_name);
            updateProductGallery(studiouWcfppSession.preview_url || studiouWcfppSession.thumbnail_url);
        }

        // ==========================================
        // Drag and drop
        // ==========================================
        $dropzone.on('dragover dragenter', function (e) {
            e.preventDefault();
            e.stopPropagation();
            $(this).addClass('studiou-fpp-dragover');
        });

        $dropzone.on('dragleave drop', function (e) {
            e.preventDefault();
            e.stopPropagation();
            $(this).removeClass('studiou-fpp-dragover');
        });

        $dropzone.on('drop', function (e) {
            var files = e.originalEvent.dataTransfer.files;
            if (files.length > 0) {
                handleFile(files[0]);
            }
        });

        $dropzone.on('click', function () {
            if (!isUploading) {
                $fileInput.trigger('click');
            }
        });

        $fileInput.on('change', function () {
            if (this.files.length > 0) {
                handleFile(this.files[0]);
            }
        });

        // Remove file
        $removeBtn.on('click', function () {
            removeUploadedFile();
        });

        // ==========================================
        // Upload logic
        // ==========================================
        function handleFile(file) {
            if (isUploading) return;

            var maxBytes = maxFileSize * 1024 * 1024;
            if (file.size > maxBytes) {
                showMessage(studiouWcfppFront.i18n.fileTooLarge.replace('%s', maxFileSize), 'error');
                return;
            }

            clearMessages();
            startChunkedUpload(file);
        }

        function startChunkedUpload(file) {
            isUploading = true;
            var totalChunks = Math.ceil(file.size / chunkSize);
            var uploadId = 'upload_' + Date.now() + '_' + Math.random().toString(36).substr(2, 9);
            var currentChunk = 0;

            $dropzone.hide();
            $progress.show();

            function uploadNextChunk() {
                var start = currentChunk * chunkSize;
                var end = Math.min(start + chunkSize, file.size);
                var blob = file.slice(start, end);

                var formData = new FormData();
                formData.append('action', 'studiou_wcfpp_upload_chunk');
                formData.append('nonce', studiouWcfppFront.nonce);
                formData.append('product_id', productId);
                formData.append('upload_id', uploadId);
                formData.append('chunk_index', currentChunk);
                formData.append('total_chunks', totalChunks);
                formData.append('file_name', file.name);
                formData.append('file_size', file.size);
                formData.append('chunk', blob, 'chunk');

                var isLastChunk = (currentChunk === totalChunks - 1);
                if (isLastChunk) {
                    $progressFill.css('width', '100%');
                    $progressText.text(studiouWcfppFront.i18n.processing || 'Processing...');
                }

                $.ajax({
                    url: studiouWcfppFront.ajaxUrl,
                    type: 'POST',
                    data: formData,
                    processData: false,
                    contentType: false,
                    timeout: isLastChunk ? 120000 : 30000,
                    success: function (response) {
                        if (response.success) {
                            if (!isLastChunk) {
                                currentChunk++;
                                var percent = Math.round((currentChunk / totalChunks) * 100);
                                $progressFill.css('width', percent + '%');
                                $progressText.text(percent + '%');
                            }

                            if (response.data.complete) {
                                uploadedAttachmentId = response.data.attachment_id;
                                uploadedFileRecordId = response.data.file_record_id;

                                storeInSession(
                                    response.data.attachment_id,
                                    response.data.file_record_id,
                                    response.data.file_name
                                );

                                showPreview(response.data.thumbnail_url, response.data.file_name);
                                updateProductGallery(response.data.preview_url || response.data.thumbnail_url);
                                $progress.hide();
                                isUploading = false;
                            } else {
                                uploadNextChunk();
                            }
                        } else {
                            uploadFailed(response.data ? response.data.message : studiouWcfppFront.i18n.uploadError);
                        }
                    },
                    error: function () {
                        uploadFailed(studiouWcfppFront.i18n.uploadError);
                    }
                });
            }

            uploadNextChunk();
        }

        // ==========================================
        // Session management
        // ==========================================
        function storeInSession(attachmentId, fileRecordId, fileName) {
            $.ajax({
                url: studiouWcfppFront.ajaxUrl,
                type: 'POST',
                data: {
                    action: 'studiou_wcfpp_set_upload_session',
                    nonce: studiouWcfppFront.nonce,
                    attachment_id: attachmentId,
                    file_record_id: fileRecordId,
                    file_name: fileName
                }
            });
        }

        function clearSession() {
            $.ajax({
                url: studiouWcfppFront.ajaxUrl,
                type: 'POST',
                data: {
                    action: 'studiou_wcfpp_clear_upload_session',
                    nonce: studiouWcfppFront.nonce
                }
            });
        }

        // ==========================================
        // Product gallery image replacement
        // ==========================================
        function updateProductGallery(imageUrl) {
            if (!imageUrl) return;

            var selectors = [
                '.woocommerce-product-gallery__image img',
                '.product .wp-post-image',
                '.product-image img',
                '.product-thumbnail img',
                '.entry-summary img.attachment-woocommerce_thumbnail',
                '.product-gallery img:first'
            ];

            var $img = null;
            for (var i = 0; i < selectors.length; i++) {
                $img = $(selectors[i]).first();
                if ($img.length) break;
            }
            if (!$img || !$img.length) return;

            if (!originalGalleryImages.src) {
                originalGalleryImages.src = $img.attr('src');
                originalGalleryImages.srcset = $img.attr('srcset') || '';
                originalGalleryImages.sizes = $img.attr('sizes') || '';
                var $link = $img.closest('a');
                if ($link.length) originalGalleryImages.href = $link.attr('href');
            }

            $img.attr('src', imageUrl).removeAttr('srcset').removeAttr('sizes');
            var $link = $img.closest('a');
            if ($link.length) $link.attr('href', imageUrl);
        }

        function restoreProductGallery() {
            if (!originalGalleryImages.src) return;

            var selectors = [
                '.woocommerce-product-gallery__image img',
                '.product .wp-post-image',
                '.product-image img',
                '.product-thumbnail img',
                '.entry-summary img.attachment-woocommerce_thumbnail',
                '.product-gallery img:first'
            ];

            var $img = null;
            for (var i = 0; i < selectors.length; i++) {
                $img = $(selectors[i]).first();
                if ($img.length) break;
            }
            if (!$img || !$img.length) return;

            $img.attr('src', originalGalleryImages.src);
            if (originalGalleryImages.srcset) $img.attr('srcset', originalGalleryImages.srcset);
            if (originalGalleryImages.sizes) $img.attr('sizes', originalGalleryImages.sizes);
            if (originalGalleryImages.href) $img.closest('a').attr('href', originalGalleryImages.href);

            originalGalleryImages = {};
        }

        // ==========================================
        // UI helpers
        // ==========================================
        function uploadFailed(message) {
            isUploading = false;
            $progress.hide();
            $dropzone.show();
            showMessage(message, 'error');
            $fileInput.val('');
        }

        function showPreview(thumbnailUrl, fileName) {
            if (thumbnailUrl) {
                $previewImg.attr('src', thumbnailUrl).show();
            } else {
                $previewImg.hide();
            }
            $previewName.text(fileName);
            $preview.show();
            $dropzone.hide();
        }

        function removeUploadedFile() {
            if (!uploadedFileRecordId) return;

            $.ajax({
                url: studiouWcfppFront.ajaxUrl,
                type: 'POST',
                data: {
                    action: 'studiou_wcfpp_remove_upload',
                    nonce: studiouWcfppFront.nonce,
                    file_record_id: uploadedFileRecordId
                },
                success: function () {
                    resetUpload();
                }
            });
        }

        function resetUpload() {
            uploadedAttachmentId = null;
            uploadedFileRecordId = null;
            clearSession();
            restoreProductGallery();
            $preview.hide();
            $previewImg.attr('src', '');
            $previewName.text('');
            $dropzone.show();
            $fileInput.val('');
            clearMessages();
        }

        function showMessage(text, type) {
            var cls = type === 'error' ? 'studiou-fpp-msg-error' : 'studiou-fpp-msg-success';
            $messages.html('<div class="studiou-fpp-msg ' + cls + '">' + escHtml(text) + '</div>');
        }

        function clearMessages() {
            $messages.empty();
        }

        function escHtml(str) {
            var div = document.createElement('div');
            div.appendChild(document.createTextNode(str));
            return div.innerHTML;
        }

        // ==========================================
        // Quantity discount tier display + live price update
        // ==========================================
        initQtyTiers();
        initVariantTableTiers();

        function initVariantTableTiers() {
            // Handles custom variant-table plugins (e.g. pvtfw / product-variant-table-for-woocommerce)
            // where each variation is rendered as a <tr> with its own qty input and price.
            var tierData = (typeof window.studiouFppTierData === 'object' && window.studiouFppTierData) ? window.studiouFppTierData : null;
            if (!tierData) {
                return;
            }
            var $table = $('table.variant').first();
            if (!$table.length) {
                return;
            }

            var i18n = studiouWcfppFront.i18n;

            $table.find('tbody > tr').each(function () {
                var $row = $(this);
                var $cartBtn = $row.find('.pvtfw_variant_table_cart_btn').first();
                var variantId = $cartBtn.length ? String($cartBtn.data('variant')) : '';
                if (!variantId) {
                    var $qtyInput = $row.find('input.qty').first();
                    variantId = $qtyInput.attr('id') || '';
                }
                if (!variantId || !tierData[variantId]) {
                    return;
                }

                var cfg = tierData[variantId];
                var tiers = cfg.tiers || [];
                var basePrice = parseFloat(cfg.base_price) || 0;
                if (tiers.length === 0 || basePrice <= 0) {
                    return;
                }

                var $priceCell = $row.find('td[data-title="Price"]').first();
                if (!$priceCell.length) $priceCell = $row.find('.woocommerce-Price-amount').first().closest('td');
                var $priceEl = $priceCell.find('.woocommerce-Price-amount').first();
                var $qty = $row.find('input.qty').first();
                if (!$priceEl.length || !$qty.length) {
                    return;
                }

                // Append a compact tier summary beneath the price
                var tierListHtml = '<div class="studiou-fpp-row-tiers" title="' + escHtml(i18n.qtyTiersTitle) + '">';
                tierListHtml += '<span class="dashicons dashicons-tag"></span>';
                tierListHtml += '<span class="studiou-fpp-row-tiers-list">';
                for (var i = 0; i < tiers.length; i++) {
                    var t = tiers[i];
                    tierListHtml += '<span class="studiou-fpp-row-tier">' + t.from_qty + '+: −' + formatPercent(t.percent) + '</span>';
                }
                tierListHtml += '</span></div>';
                $priceCell.append(tierListHtml);

                // Store the original price HTML so we can revert when qty falls below the first tier
                if (!$priceEl.data('studiou-fpp-base-html')) {
                    $priceEl.data('studiou-fpp-base-html', $priceEl.html());
                }

                // Bind qty change handlers to update this row's price display
                var handler = function () {
                    updateRowPrice($row, tiers, basePrice, $priceEl, $qty);
                };
                $qty.on('input change keyup', handler);
                // pvtfw ± buttons sit next to the input; they dispatch change events on the input,
                // but some themes intercept them — bind click too
                $row.find('.qty-count').on('click', function () {
                    setTimeout(handler, 0);
                });

                // Initial update (qty=1 usually, just to install the "Save X%" indicator if applicable)
                updateRowPrice($row, tiers, basePrice, $priceEl, $qty);
            });
        }

        function updateRowPrice($row, tiers, basePrice, $priceEl, $qty) {
            var qty = parseInt($qty.val(), 10) || 1;
            var tier = resolveTierSimple(tiers, qty);
            $row.find('.studiou-fpp-row-save-badge').remove();

            if (!tier || tier.percent <= 0) {
                // Revert to original HTML
                var base = $priceEl.data('studiou-fpp-base-html');
                if (base) {
                    $priceEl.html(base);
                }
                return;
            }

            var unit = basePrice * (1 - tier.percent / 100);
            $priceEl.html(formatPriceInner(unit));

            var badge = '<span class="studiou-fpp-row-save-badge">−' + formatPercent(tier.percent) + '</span>';
            $priceEl.after(badge);
        }

        function resolveTierSimple(tiers, qty) {
            var match = null;
            for (var i = 0; i < tiers.length; i++) {
                if (tiers[i].from_qty <= qty) match = tiers[i];
                else break;
            }
            return match;
        }

        function formatPercent(percent) {
            var p = parseFloat(percent) || 0;
            var str = p.toFixed(2).replace(/\.?0+$/, '');
            return str + ' %';
        }

        function formatPriceInner(amount) {
            var curr = studiouWcfppFront.currency || {};
            var decimals = parseInt(curr.decimals, 10);
            if (isNaN(decimals)) decimals = 2;
            var decSep = curr.decimalSeparator || '.';
            var thouSep = curr.thousandSeparator || ',';
            var fmt = curr.priceFormat || '%1$s%2$s';
            var symbol = curr.symbol || '';

            var fixed = parseFloat(amount).toFixed(decimals);
            var parts = fixed.split('.');
            var intPart = parts[0].replace(/\B(?=(\d{3})+(?!\d))/g, thouSep);
            var decPart = parts.length > 1 ? parts[1] : '';
            var numStr = decPart ? intPart + decSep + decPart : intPart;

            var symbolHtml = '<span class="woocommerce-Price-currencySymbol">' + symbol + '</span>';
            return fmt.replace('%1$s', symbolHtml).replace('%2$s', numStr);
        }

        function initQtyTiers() {
            var $container = $('.studiou-fpp-qty-tiers-display');
            var $form = $('form.variations_form').first();
            if (!$container.length || !$form.length) {
                return;
            }

            var currentTiers = [];
            var currentBasePrice = 0;

            $form.on('found_variation', function (event, variation) {
                currentTiers = (variation && variation.studiou_fpp_qty_tiers) ? variation.studiou_fpp_qty_tiers : [];
                currentBasePrice = (variation && variation.studiou_fpp_base_price) ? parseFloat(variation.studiou_fpp_base_price) : 0;
                // WC re-renders .single_variation on every selection, so defer a tick to run after it
                setTimeout(function () {
                    renderTierTable();
                    updateDisplayedPrice();
                }, 0);
            });

            $form.on('reset_data', function () {
                currentTiers = [];
                currentBasePrice = 0;
                $container.hide().empty();
            });

            // Live price update on quantity change — broad listener so themes with non-standard
            // qty input placement still trigger the update.
            $(document).on('input change keyup', 'input.qty, input[name="quantity"]', function () {
                updateDisplayedPrice();
            });

            function renderTierTable() {
                if (!currentTiers || currentTiers.length === 0) {
                    $container.hide().empty();
                    return;
                }

                var i18n = studiouWcfppFront.i18n;
                var html = '<div class="studiou-fpp-qty-tiers-box">';
                html += '<h4><span class="dashicons dashicons-tag"></span> ' + escHtml(i18n.qtyTiersTitle || 'Quantity Discount') + '</h4>';
                html += '<table class="studiou-fpp-qty-tiers-table-display"><thead><tr>';
                html += '<th>' + escHtml(i18n.qtyTiersFromQty || 'From Qty') + '</th>';
                html += '<th>' + escHtml(i18n.qtyTiersDiscount || 'Discount') + '</th>';
                html += '<th>' + escHtml(i18n.qtyTiersUnitPrice || 'Unit Price') + '</th>';
                html += '</tr></thead><tbody>';

                for (var i = 0; i < currentTiers.length; i++) {
                    var t = currentTiers[i];
                    var unit = computeDiscounted(currentBasePrice, t.percent);
                    html += '<tr data-from-qty="' + t.from_qty + '">';
                    html += '<td>' + t.from_qty + '+</td>';
                    html += '<td>' + formatPercent(t.percent) + '</td>';
                    html += '<td>' + formatPrice(unit) + '</td>';
                    html += '</tr>';
                }
                html += '</tbody></table></div>';

                $container.html(html).show();
            }

            function findPriceElement() {
                var selectors = [
                    '.single_variation .woocommerce-variation-price .woocommerce-Price-amount',
                    'form.variations_form .woocommerce-variation-price .woocommerce-Price-amount',
                    '.single_variation_wrap .woocommerce-Price-amount',
                    'form.variations_form .price .woocommerce-Price-amount'
                ];
                for (var i = 0; i < selectors.length; i++) {
                    var $el = $(selectors[i]).first();
                    if ($el.length) return $el;
                }
                return $();
            }

            function findQtyInput() {
                var $qty = $form.find('input.qty').first();
                if (!$qty.length) $qty = $('input.qty').first();
                if (!$qty.length) $qty = $('input[name="quantity"]').first();
                return $qty;
            }

            function updateDisplayedPrice() {
                if (!currentBasePrice || !currentTiers || currentTiers.length === 0) {
                    highlightActiveTierRow(0);
                    return;
                }
                var $qty = findQtyInput();
                var qty = $qty.length ? (parseInt($qty.val(), 10) || 1) : 1;
                var tier = resolveTier(currentTiers, qty);
                var unit = tier ? computeDiscounted(currentBasePrice, tier.percent) : currentBasePrice;

                var $wcPrice = findPriceElement();
                if ($wcPrice.length) {
                    $wcPrice.html(formatPriceInner(unit));
                }

                highlightActiveTierRow(tier ? tier.from_qty : 0);
            }

            function highlightActiveTierRow(fromQty) {
                $container.find('tr').removeClass('studiou-fpp-qty-tier-active');
                if (fromQty > 0) {
                    $container.find('tr[data-from-qty="' + fromQty + '"]').addClass('studiou-fpp-qty-tier-active');
                }
            }

            function resolveTier(tiers, qty) {
                var match = null;
                for (var i = 0; i < tiers.length; i++) {
                    if (tiers[i].from_qty <= qty) {
                        match = tiers[i];
                    } else {
                        break;
                    }
                }
                return match;
            }

            function computeDiscounted(basePrice, percent) {
                var p = parseFloat(percent) || 0;
                if (p <= 0) return basePrice;
                return basePrice * (1 - p / 100);
            }

            function formatPercent(percent) {
                var p = parseFloat(percent) || 0;
                // Strip trailing zeros
                var str = p.toFixed(2).replace(/\.?0+$/, '');
                return str + ' %';
            }

            function formatPrice(amount) {
                return '<span class="woocommerce-Price-amount amount">' + formatPriceInner(amount) + '</span>';
            }

            function formatPriceInner(amount) {
                var curr = studiouWcfppFront.currency || {};
                var decimals = parseInt(curr.decimals, 10);
                if (isNaN(decimals)) decimals = 2;
                var decSep = curr.decimalSeparator || '.';
                var thouSep = curr.thousandSeparator || ',';
                var fmt = curr.priceFormat || '%1$s%2$s';
                var symbol = curr.symbol || '';

                var fixed = parseFloat(amount).toFixed(decimals);
                var parts = fixed.split('.');
                var intPart = parts[0].replace(/\B(?=(\d{3})+(?!\d))/g, thouSep);
                var decPart = parts.length > 1 ? parts[1] : '';
                var numStr = decPart ? intPart + decSep + decPart : intPart;

                var symbolHtml = '<span class="woocommerce-Price-currencySymbol">' + symbol + '</span>';
                return fmt.replace('%1$s', symbolHtml).replace('%2$s', numStr);
            }
        }
    });
})(jQuery);