<?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 area below the variation table on single product page
        add_action('woocommerce_single_product_summary', array($this, 'render_upload_area'), 35);

        // 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
        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'));
    }

    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);

        // Pass existing state (WC session or cookie fallback) to JS for restore on page load
        $session_data = array();
        $resolved = self::resolve_uploaded_file($this->db);
        if ($resolved) {
            $att_id  = (int) $resolved['attachment_id'];
            $thumb   = wp_get_attachment_image_src($att_id, 'thumbnail');
            $preview = wp_get_attachment_image_src($att_id, 'woocommerce_single');
            $session_data = array(
                'attachment_id'  => $att_id,
                'file_record_id' => (int) $resolved['file_record_id'],
                'file_name'      => $resolved['file_name'],
                'thumbnail_url'  => $thumb ? $thumb[0] : '',
                'preview_url'    => $preview ? $preview[0] : ($thumb ? $thumb[0] : ''),
            );
        }

        wp_localize_script('studiou-wcfpp-frontend', 'studiouWcfppSession', $session_data);

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

    /**
     * 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.
     */
    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 (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;
    }

    /**
     * Resolve the currently "attached" upload for this visitor, checking WC session first
     * and falling back to a first-party cookie written at upload time.
     *
     * The cookie fallback is required because pvtfw 1.9.3+ / WC 10.7.0+ may route
     * Add to Cart through the WC Store API, which identifies the session via the
     * Cart-Token header rather than the classic wp_woocommerce_session_* cookie —
     * that path sees a different (empty) session than the one the upload wrote to.
     *
     * @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();
    }
}