<?php

if ( ! defined( 'ABSPATH' ) ) {
    exit;
}

class ACAI_API
{
    public function __construct()
    {
        add_action('rest_api_init', array($this, 'register_rest_routes'));
    }

    public function register_rest_routes()
    {
        register_rest_route('a2cai/v1', '/products/batch', array(
            'methods' => 'GET',
            'callback' => array($this, 'get_product_batch'),
            'permission_callback' => array($this, 'check_batch_permissions'),
        ));

        register_rest_route('a2cai/v1', '/health', array(
            'methods' => 'GET',
            'callback' => array($this, 'get_health'),
            'permission_callback' => array($this, 'check_batch_permissions'),
        ));
    }

    public function get_health(WP_REST_Request $request)
    {
        global $wp_version;

        $health_data = array(
            'status' => 'healthy',
            'version' => ACAI_VERSION,
            'environment' => array(
                'wordpress' => $wp_version,
                'woocommerce' => defined('WC_VERSION') ? WC_VERSION : null,
                'php' => PHP_VERSION,
            ),
            'timestamp' => current_time('mysql'),
        );

        return rest_ensure_response($health_data);
    }

    public function get_product_batch(WP_REST_Request $request)
    {
        $batch_size = 500;
        $batch_number = $request->get_param('batch_number') ? max(1, intval($request->get_param('batch_number'))) : 1;
        $offset = ($batch_number - 1) * $batch_size;

        $args = array(
            'post_type'      => 'product',
            'post_status'    => 'publish',
            'posts_per_page' => $batch_size,
            'offset'         => $offset,
            'fields'         => 'ids', // Only get post IDs for efficiency
        );

        $products_query = new WP_Query($args);
        $products = array_map(function ($post_id) {
            $product = wc_get_product($post_id);

            // Main image
            $image_id = get_post_thumbnail_id($post_id);
            $image_src = wp_get_attachment_image_src($image_id, 'full');
            $image_url = $image_src ? $image_src[0] : null;

            // Gallery images
            $gallery_ids = $product->get_gallery_image_ids();
            $image_urls = array();
            foreach ($gallery_ids as $gallery_id) {
                $gallery_src = wp_get_attachment_image_src($gallery_id, 'full');
                if ($gallery_src) {
                    $image_urls[] = $gallery_src[0];
                }
            }

            $in_stock = $product->is_in_stock();

            $is_published = $product->get_status() === 'publish';
            $visible = $is_published && $product->get_catalog_visibility() !== 'hidden';

            // Categories
            $category_ids = $product->get_category_ids();
            $categories = array();
            foreach ($category_ids as $cat_id) {
                $term = get_term($cat_id, 'product_cat');
                if ($term && !is_wp_error($term)) {
                    $categories[] = $term->name;
                }
            }
            $category = !empty($categories) ? implode(' > ', $categories) : null;

            // Rating and reviews
            $rating = $product->get_average_rating();
            $review_count = $product->get_review_count();

            // Compare at price (regular price when on sale)
            $regular_price = $product->get_regular_price();
            $sale_price = $product->get_sale_price();
            $compare_at_price = ($sale_price && $regular_price !== $sale_price) ? floatval($regular_price) : null;

            // Weight
            $weight = $product->get_weight();
            $weight_unit = $weight ? get_option('woocommerce_weight_unit', 'kg') : null;

            return array(
                'id' => strval($post_id),
                'title' => $product->get_title(),
                'price' => $product->get_price() ? floatval($product->get_price()) : null,
                'imageUrl' => $image_url,
                'inStock' => $in_stock,
                'visible' => $visible,

                // Basic Product Metadata
                'description' => $product->get_description() ?: $product->get_short_description(),
                'brand' => $this->get_product_brand($product, $post_id),
                'category' => $category,
                'currency' => get_woocommerce_currency(),
                'productUrl' => get_permalink($post_id),
                'rating' => $rating ? floatval($rating) : null,
                'reviewCount' => $review_count ? intval($review_count) : null,
                'compareAtPrice' => $compare_at_price,
                'sku' => $product->get_sku() ?: null,
                'stockQuantity' => $product->get_stock_quantity(),
                'imageUrls' => !empty($image_urls) ? $image_urls : null,

                // Packaging & Sizing - only pass weight from WooCommerce
                // packCount, itemSizeValue, itemSizeUnit, attributes will be AI-extracted during indexing
                'weight' => $weight ? floatval($weight) : null,
                'weightUnit' => $weight_unit,
            );
        }, $products_query->posts);

        $total_products = $products_query->found_posts;
        $more_products = $total_products > $offset + count($products);

        return rest_ensure_response(array(
            'products'      => $products,
            'moreBatches'   => $more_products,
            'totalProducts' => $total_products,
            'currentBatch'  => $batch_number,
            'totalBatches'  => ceil($total_products / $batch_size)
        ));
    }

    /**
     * Get product brand from various sources
     */
    private function get_product_brand($product, $post_id)
    {
        // Check for brand taxonomy (used by various brand plugins)
        $brand_taxonomies = array('product_brand', 'pa_brand', 'brand', 'yith_product_brand');
        foreach ($brand_taxonomies as $taxonomy) {
            if (taxonomy_exists($taxonomy)) {
                $terms = wc_get_product_terms($post_id, $taxonomy, array('fields' => 'names'));
                if (!empty($terms)) {
                    return $terms[0];
                }
            }
        }

        // Check for brand attribute
        $attributes = $product->get_attributes();
        foreach ($attributes as $attribute) {
            $name = strtolower($attribute->get_name());
            if (strpos($name, 'brand') !== false || strpos($name, 'marca') !== false) {
                if ($attribute->is_taxonomy()) {
                    $terms = wc_get_product_terms($post_id, $attribute->get_name(), array('fields' => 'names'));
                    if (!empty($terms)) {
                        return $terms[0];
                    }
                } else {
                    $options = $attribute->get_options();
                    if (!empty($options)) {
                        return $options[0];
                    }
                }
            }
        }

        return null;
    }

    public function check_batch_permissions(WP_REST_Request $request)
    {
        $auth_header = $request->get_header('Authorization');
        if (!$auth_header || strpos($auth_header, 'Bearer ') !== 0) {
            return new WP_Error('invalid_token', esc_html__('Invalid or missing bearer token', 'add-to-cart-ai'), array('status' => 401));
        }

        $token = substr($auth_header, 7);
        $stored_key = get_option('a2cai_activation_key');

        if (!hash_equals($stored_key, $token)) {
            return new WP_Error('invalid_token', esc_html__('Invalid bearer token', 'add-to-cart-ai'), array('status' => 401));
        }

        return true;
    }
}

new ACAI_API();