<?php
if (!defined('WPINC')) {
    die;
}

class Studiou_WC_FPP_Single_Product {

    /** @var Studiou_WC_FPP_DB */
    private $db;

    public function __construct($db) {
        $this->db = $db;

        // Render upload cards UI at priority 35 on single product page.
        // Also suppress pvtfw's variant table + available-options button on FPP products.
        add_action('wp', array($this, 'maybe_suppress_pvtfw'), 5);
        add_action('woocommerce_single_product_summary', array($this, 'render_upload_area'), 35);

        // Add a body class on FPP product pages for CSS scoping
        add_filter('body_class', array($this, 'body_class'));

        // Server-side validation: block add-to-cart without photo (priority 1 = very early)
        add_filter('woocommerce_add_to_cart_validation', array($this, 'validate_add_to_cart'), 1, 6);

        // Safety net: if item was added without photo, remove it immediately
        add_action('woocommerce_add_to_cart', array($this, 'check_after_add_to_cart'), 10, 6);

        // AJAX: store uploaded file reference in WC session (legacy — shortcode path)
        add_action('wp_ajax_studiou_wcfpp_set_upload_session', array($this, 'ajax_set_upload_session'));
        add_action('wp_ajax_nopriv_studiou_wcfpp_set_upload_session', array($this, 'ajax_set_upload_session'));
        add_action('wp_ajax_studiou_wcfpp_clear_upload_session', array($this, 'ajax_clear_upload_session'));
        add_action('wp_ajax_nopriv_studiou_wcfpp_clear_upload_session', array($this, 'ajax_clear_upload_session'));
    }

    /**
     * Detach pvtfw's variant-table + available-options-button hooks on FPP products.
     * pvtfw exposes its instances as globals $pvtfw_print_table and $pvtfw_available_btn;
     * the table hook/priority is derived from the same option pvtfw itself reads
     * (pvtfw_variant_table_place, default woocommerce_after_single_product_summary_9).
     */
    public function maybe_suppress_pvtfw() {
        if (!function_exists('is_product') || !is_product()) {
            return;
        }
        $product_id = get_queried_object_id();
        if (!$product_id || !Studiou_WC_FPP_Product::is_fpp_product($product_id)) {
            return;
        }

        global $pvtfw_print_table, $pvtfw_available_btn;

        if ($pvtfw_print_table) {
            $place = get_option('pvtfw_variant_table_place', 'woocommerce_after_single_product_summary_9');
            $tail  = strrchr((string) $place, '_');
            if ($tail !== false && strlen($tail) > 1) {
                $priority = (int) ltrim($tail, '_');
                $hook     = substr($place, 0, -strlen($tail));
                if ($hook) {
                    remove_action($hook, array($pvtfw_print_table, 'print_table'), $priority);
                }
            }
        } elseif (defined('WP_DEBUG') && WP_DEBUG) {
            error_log('STUDIOU FPP: $pvtfw_print_table not found; cannot detach pvtfw variant table.');
        }

        if ($pvtfw_available_btn) {
            remove_action('woocommerce_single_product_summary', array($pvtfw_available_btn, 'available_options_btn'), 11);
        }
    }

    public function body_class($classes) {
        if (function_exists('is_product') && is_product()) {
            $product_id = get_queried_object_id();
            if ($product_id && Studiou_WC_FPP_Product::is_fpp_product($product_id)) {
                $classes[] = 'studiou-fpp-product-page';
            }
        }
        return $classes;
    }

    public function render_upload_area() {
        global $product;
        if (!$product || !Studiou_WC_FPP_Product::is_fpp_product($product->get_id())) {
            return;
        }

        wp_enqueue_style('studiou-wcfpp-frontend');
        wp_enqueue_script('studiou-wcfpp-frontend');

        $product_id    = $product->get_id();
        $max_file_size = Studiou_WC_FPP_Product::get_product_max_file_size($product_id);
        $max_uploads   = Studiou_WC_FPP_Product::get_product_max_uploads($product_id);

        // Variant list (id, label, base_price, tiers) — injected into the files-cards JS
        $variants = $this->build_variant_list($product);

        // Existing batch files (rehydrate the card stack across reloads)
        $batch_files = self::resolve_batch_files($this->db, $product_id);
        $batch_cards = array();
        $hero_preview_url = '';
        foreach ($batch_files as $row) {
            $att_id  = (int) $row->attachment_id;
            $thumb   = wp_get_attachment_image_src($att_id, 'thumbnail');
            $preview = wp_get_attachment_image_src($att_id, 'woocommerce_single');
            if ($hero_preview_url === '') {
                $hero_preview_url = $preview ? $preview[0] : ($thumb ? $thumb[0] : '');
            }
            $batch_cards[] = array(
                'file_record_id' => (int) $row->id,
                'attachment_id'  => $att_id,
                'file_name'      => (string) $row->file_name,
                'thumb_url'      => $thumb ? $thumb[0] : ($preview ? $preview[0] : ''),
                'variation_id'   => (int) $row->variation_id,
            );
        }

        wp_localize_script('studiou-wcfpp-frontend', 'studiouFppCardData', array(
            'productId'      => $product_id,
            'variants'       => $variants,
            'maxUploads'     => $max_uploads,
            'batchFiles'     => $batch_cards,
            'heroPreviewUrl' => $hero_preview_url,
        ));

        // Keep studiouWcfppSession populated for legacy JS code paths that still read it
        wp_localize_script('studiou-wcfpp-frontend', 'studiouWcfppSession', array());

        include STUDIOU_WCFPP_PLUGIN_DIR . 'views/single-product-upload.php';

        if (is_product() && Studiou_WC_FPP_Product::is_fpp_product($product_id)) {
            // Render the order-overview panel below the cards (see views/single-product-order-overview.php)
            $cart = function_exists('WC') ? WC()->cart : null;
            include STUDIOU_WCFPP_PLUGIN_DIR . 'views/single-product-order-overview.php';
        }
    }

    /**
     * Produce the array of variation descriptors consumed by the upload-card JS.
     * One entry per in-stock, purchasable variation: id, label, base_price, tiers.
     */
    private function build_variant_list($product) {
        if (!$product || !$product->is_type('variable')) {
            return array();
        }
        $variants = array();
        foreach ($product->get_children() as $variation_id) {
            $variation = wc_get_product($variation_id);
            if (!$variation || !$variation->is_purchasable() || !$variation->variation_is_visible()) {
                continue;
            }
            $base_price = get_post_meta($variation_id, '_price', true);
            $label_parts = array();
            foreach ($variation->get_attributes() as $attr_name => $attr_value) {
                if ($attr_value === '') {
                    continue;
                }
                $taxonomy  = str_replace('attribute_', '', $attr_name);
                $term      = taxonomy_exists($taxonomy) ? get_term_by('slug', $attr_value, $taxonomy) : null;
                $label_parts[] = $term ? $term->name : $attr_value;
            }
            $tiers = class_exists('Studiou_WC_FPP_Pricing')
                ? Studiou_WC_FPP_Pricing::get_tiers($variation_id)
                : array();

            $variants[] = array(
                'id'         => (int) $variation_id,
                'label'      => implode(' / ', $label_parts),
                'base_price' => ($base_price !== '' && $base_price !== false) ? (float) $base_price : 0.0,
                'tiers'      => $tiers,
                'in_stock'   => $variation->is_in_stock(),
            );
        }
        return $variants;
    }

    /**
     * Resolve whether a product_id or its parent is FPP-enabled.
     */
    private function resolve_fpp_product_id($product_id, $variation_id = 0) {
        // Check direct product
        if (Studiou_WC_FPP_Product::is_fpp_product($product_id)) {
            return $product_id;
        }

        // Check parent of the product (in case product_id is variation)
        $product = wc_get_product($product_id);
        if ($product && $product->get_parent_id() && Studiou_WC_FPP_Product::is_fpp_product($product->get_parent_id())) {
            return $product->get_parent_id();
        }

        // Check variation_id's parent
        if ($variation_id && $variation_id !== $product_id) {
            $variation = wc_get_product($variation_id);
            if ($variation && $variation->get_parent_id() && Studiou_WC_FPP_Product::is_fpp_product($variation->get_parent_id())) {
                return $variation->get_parent_id();
            }
        }

        return false;
    }

    /**
     * Validate before add-to-cart: block if FPP product and no photo reference resolvable.
     *
     * 1.5.0: the per-card Add-to-Cart path pre-stamps $cart_item_data['studiou_fpp_file_record_id']
     * via our ajax_add_file_to_cart handler — accept that as the primary signal. Fall back to the
     * legacy visitor-level resolver for the shortcode path.
     */
    public function validate_add_to_cart($passed, $product_id, $quantity, $variation_id = 0, $variations = array(), $cart_item_data = array()) {
        $fpp_id = $this->resolve_fpp_product_id($product_id, $variation_id);
        if (!$fpp_id) {
            return $passed;
        }

        if (!empty($cart_item_data['studiou_fpp_file_record_id'])) {
            $record = $this->db->get_file_record((int) $cart_item_data['studiou_fpp_file_record_id']);
            if ($record && (int) $record->order_id === 0) {
                return $passed;
            }
        }

        if (self::resolve_uploaded_file($this->db)) {
            return $passed;
        }

        wc_add_notice(__('Please upload a photo before adding to cart.', 'studiou-wc-free-photo-product'), 'error');
        return false;
    }

    /**
     * Return all upload records belonging to the current visitor's batch
     * that are not yet attached to an order, optionally scoped to a product.
     *
     * @return array<int,object>  list of DB rows, oldest first (ascending id)
     */
    public static function resolve_batch_files(Studiou_WC_FPP_DB $db, $product_id = 0) {
        $token = Studiou_WC_FPP_Upload::get_batch_token();
        if (empty($token)) {
            return array();
        }
        return $db->get_batch_files($token, (int) $product_id);
    }

    /**
     * Resolve the currently "attached" upload for this visitor (legacy single-file path).
     * Checks WC session first, then legacy cookie pair, and finally the first file in the
     * current batch as a last-resort fallback. Used only by the shortcode flow on 1.5+ —
     * the product-detail page uses resolve_batch_files() and pre-stamped file_record_id.
     *
     * @return array{attachment_id:int,file_record_id:int,file_name:string,thumb_url:string}|null
     */
    public static function resolve_uploaded_file(Studiou_WC_FPP_DB $db) {
        $attachment_id  = 0;
        $file_record_id = 0;
        $file_name      = '';
        $thumb_url      = '';

        if (function_exists('WC') && WC()->session) {
            $attachment_id  = (int) WC()->session->get('studiou_fpp_attachment_id');
            $file_record_id = (int) WC()->session->get('studiou_fpp_file_record_id');
            $file_name      = (string) WC()->session->get('studiou_fpp_file_name');
            $thumb_url      = (string) WC()->session->get('studiou_fpp_thumb_url');
        }

        if ($attachment_id <= 0 || $file_record_id <= 0) {
            $cookie_att = isset($_COOKIE[Studiou_WC_FPP_Upload::COOKIE_ATTACHMENT])
                ? (int) $_COOKIE[Studiou_WC_FPP_Upload::COOKIE_ATTACHMENT] : 0;
            $cookie_rec = isset($_COOKIE[Studiou_WC_FPP_Upload::COOKIE_RECORD])
                ? (int) $_COOKIE[Studiou_WC_FPP_Upload::COOKIE_RECORD] : 0;
            if ($cookie_att > 0 && $cookie_rec > 0) {
                $attachment_id  = $cookie_att;
                $file_record_id = $cookie_rec;
                $file_name      = '';
                $thumb_url      = '';
            }
        }

        if ($attachment_id <= 0 || $file_record_id <= 0) {
            return null;
        }

        $record = $db->get_file_record($file_record_id);
        if (!$record) {
            return null;
        }
        if ((int) $record->attachment_id !== $attachment_id) {
            return null;
        }
        // A record already attached to an order is no longer "in flight" for add-to-cart
        if ((int) $record->order_id !== 0) {
            return null;
        }

        if ($file_name === '') {
            $file_name = (string) $record->file_name;
        }
        if ($thumb_url === '') {
            $thumb = wp_get_attachment_image_src($attachment_id, 'thumbnail');
            if ($thumb) {
                $thumb_url = $thumb[0];
            } else {
                $thumb_url = (string) wp_get_attachment_url($attachment_id);
            }
        }

        return array(
            'attachment_id'  => $attachment_id,
            'file_record_id' => $file_record_id,
            'file_name'      => $file_name,
            'thumb_url'      => $thumb_url,
        );
    }

    /**
     * Safety net: if an FPP item was added without photo data, remove it.
     * This catches cases where validation was somehow bypassed.
     */
    public function check_after_add_to_cart($cart_item_key, $product_id, $quantity, $variation_id, $variation, $cart_item_data) {
        $fpp_id = $this->resolve_fpp_product_id($product_id, $variation_id);
        if (!$fpp_id) {
            return;
        }

        // If the cart item has no FPP attachment, remove it
        if (empty($cart_item_data['studiou_fpp_attachment_id'])) {
            WC()->cart->remove_cart_item($cart_item_key);
            wc_add_notice(__('Please upload a photo before adding to cart.', 'studiou-wc-free-photo-product'), 'error');
        }
    }

    public function ajax_set_upload_session() {
        check_ajax_referer('studiou-wcfpp-front-nonce', 'nonce');

        $attachment_id = isset($_POST['attachment_id']) ? absint($_POST['attachment_id']) : 0;
        $file_record_id = isset($_POST['file_record_id']) ? absint($_POST['file_record_id']) : 0;
        $file_name = isset($_POST['file_name']) ? sanitize_text_field($_POST['file_name']) : '';

        if (!$attachment_id || !$file_record_id) {
            wp_send_json_error(array('message' => __('Invalid file data.', 'studiou-wc-free-photo-product')));
            return;
        }

        if (WC()->session) {
            WC()->session->set('studiou_fpp_attachment_id', $attachment_id);
            WC()->session->set('studiou_fpp_file_record_id', $file_record_id);
            WC()->session->set('studiou_fpp_file_name', $file_name);

            // Store thumbnail URL directly so it can be used in cart without wp_get_attachment lookup
            $thumb_url = '';
            $thumb = wp_get_attachment_image_src($attachment_id, 'thumbnail');
            if ($thumb) {
                $thumb_url = $thumb[0];
            } else {
                $thumb_url = wp_get_attachment_url($attachment_id);
            }
            WC()->session->set('studiou_fpp_thumb_url', $thumb_url ?: '');
        }

        wp_send_json_success();
    }

    public function ajax_clear_upload_session() {
        check_ajax_referer('studiou-wcfpp-front-nonce', 'nonce');

        if (WC()->session) {
            WC()->session->set('studiou_fpp_attachment_id', null);
            WC()->session->set('studiou_fpp_file_record_id', null);
            WC()->session->set('studiou_fpp_file_name', null);
            WC()->session->set('studiou_fpp_thumb_url', null);
        }

        Studiou_WC_FPP_Upload::clear_upload_cookies();

        wp_send_json_success();
    }
}