<?php
namespace ToDownload\Hosted;

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

use ToDownload\PostTypes\DownloadPostType;
use ToDownload\Sellers\Sellers;

final class HostedProductsImporter {
	public const META_HOSTED_PRODUCT_PUBLIC_ID = '_ToDownload_hosted_product_public_id_v1';
	public const META_HOSTED_PRODUCT_EXTERNAL_ID = '_ToDownload_hosted_product_external_id_v1';
	public const META_HOSTED_PRODUCT_LAST_SYNC_AT = '_ToDownload_hosted_product_last_sync_at_v1';

	/**
	 * @return array{ok:bool,created:int,updated:int,linked:int,skipped:int,non_usd:int,error?:string}
	 */
	public static function sync_now(int $seller_user_id): array {
		$request_id = self::request_id();
		$hosted = Sellers::hosted_credentials($seller_user_id);
		$hosted_base = trim((string) ($hosted['hosted_base'] ?? ''));
		$store_public_id = trim((string) ($hosted['store_public_id'] ?? ''));
		$api_key = trim((string) ($hosted['api_key'] ?? ''));

		if ($hosted_base === '' || $store_public_id === '' || $api_key === '') {
			return [
				'ok' => false,
				'created' => 0,
				'updated' => 0,
				'linked' => 0,
				'skipped' => 0,
				'non_usd' => 0,
				'error' => 'Missing hosted connection. Please connect your store first.',
			];
		}

		$path = '/api/v1/stores/' . rawurlencode($store_public_id) . '/products?include_files=0';
		$res = HostedClient::get_json($hosted_base, $path, $api_key, $request_id);
		if (empty($res['ok'])) {
			$err = isset($res['error']) && is_array($res['error']) ? (array) $res['error'] : [];
			$msg = (string) ($res['message'] ?? ($err['message'] ?? 'Failed to fetch products'));
			return [
				'ok' => false,
				'created' => 0,
				'updated' => 0,
				'linked' => 0,
				'skipped' => 0,
				'non_usd' => 0,
				'error' => $msg,
			];
		}

		$data = isset($res['data']) && is_array($res['data']) ? (array) $res['data'] : [];
		$products = isset($data['products']) && is_array($data['products']) ? (array) $data['products'] : [];

		$created = 0;
		$updated = 0;
		$linked = 0;
		$skipped = 0;
		$non_usd = 0;

		$existing_map = self::existing_downloads_by_hosted_product_public_id($seller_user_id);
		$now = gmdate('c');

		foreach ($products as $p) {
			if (!is_array($p)) {
				$skipped += 1;
				continue;
			}

			$public_id = isset($p['publicId']) ? trim((string) $p['publicId']) : '';
			$external_id = isset($p['externalId']) ? trim((string) $p['externalId']) : '';
			$name = isset($p['name']) ? trim((string) $p['name']) : '';
			$status = isset($p['status']) ? trim((string) $p['status']) : '';
			$currency = isset($p['currency']) ? strtolower(trim((string) $p['currency'])) : '';
			$amount_minor = isset($p['amountMinor']) && is_int($p['amountMinor']) ? (int) $p['amountMinor'] : null;

			if ($public_id === '' || $name === '') {
				$skipped += 1;
				continue;
			}

			$download_id = 0;

			// If the hosted product was created via a WP download checkout, link it back.
			if ($external_id !== '' && preg_match('/^wp_download_(\d+)$/', $external_id, $m)) {
				$maybe_id = (int) ($m[1] ?? 0);
				$post = $maybe_id > 0 ? get_post($maybe_id) : null;
				if ($post instanceof \WP_Post && ($post->post_type ?? '') === DownloadPostType::POST_TYPE) {
					// Only link to the current seller's products.
					if ($seller_user_id <= 0 || (int) ($post->post_author ?? 0) === $seller_user_id) {
						$download_id = $maybe_id;
					}
				}
			}

			// If not linked by external id, check our stored mapping.
			if ($download_id <= 0 && isset($existing_map[$public_id])) {
				$download_id = (int) $existing_map[$public_id];
			}

			if ($download_id > 0) {
				update_post_meta($download_id, self::META_HOSTED_PRODUCT_PUBLIC_ID, $public_id);
				if ($external_id !== '') {
					update_post_meta($download_id, self::META_HOSTED_PRODUCT_EXTERNAL_ID, $external_id);
				}
				update_post_meta($download_id, self::META_HOSTED_PRODUCT_LAST_SYNC_AT, $now);

				if ($currency === 'usd' && is_int($amount_minor) && $amount_minor > 0) {
					$price = number_format(((float) $amount_minor) / 100.0, 2, '.', '');
					update_post_meta($download_id, '_ToDownload_price', $price);
				} elseif ($currency !== '' && $currency !== 'usd') {
					$non_usd += 1;
				}

				if (isset($existing_map[$public_id])) {
					$updated += 1;
				} else {
					$linked += 1;
				}
				continue;
			}

			// Import hosted-native products as new WP downloads.
			$post_status = ($status === 'active') ? 'publish' : 'draft';
			$new_id = wp_insert_post([
				'post_type' => DownloadPostType::POST_TYPE,
				'post_status' => $post_status,
				'post_title' => $name,
				'post_content' => '',
				'post_author' => max(0, $seller_user_id),
			], true);

			if (is_wp_error($new_id) || (int) $new_id <= 0) {
				$skipped += 1;
				continue;
			}

			$download_id = (int) $new_id;
			update_post_meta($download_id, self::META_HOSTED_PRODUCT_PUBLIC_ID, $public_id);
			if ($external_id !== '') {
				update_post_meta($download_id, self::META_HOSTED_PRODUCT_EXTERNAL_ID, $external_id);
			}
			update_post_meta($download_id, self::META_HOSTED_PRODUCT_LAST_SYNC_AT, $now);

			if ($currency === 'usd' && is_int($amount_minor) && $amount_minor > 0) {
				$price = number_format(((float) $amount_minor) / 100.0, 2, '.', '');
				update_post_meta($download_id, '_ToDownload_price', $price);
			} elseif ($currency !== '' && $currency !== 'usd') {
				$non_usd += 1;
			}

			$created += 1;
		}

		return [
			'ok' => true,
			'created' => $created,
			'updated' => $updated,
			'linked' => $linked,
			'skipped' => $skipped,
			'non_usd' => $non_usd,
		];
	}

	/**
	 * @return array<string,int>
	 */
	private static function existing_downloads_by_hosted_product_public_id(int $seller_user_id): array {
		$args = [
			'post_type' => DownloadPostType::POST_TYPE,
			'post_status' => ['publish', 'draft', 'pending', 'private'],
			'posts_per_page' => 500,
			'orderby' => 'ID',
			'order' => 'ASC',
			'fields' => 'ids',
		];
		if ($seller_user_id > 0) {
			$args['author'] = $seller_user_id;
		}

		$ids = get_posts($args);
		if (!is_array($ids)) {
			return [];
		}

		$map = [];
		foreach ($ids as $id) {
			$pid = (int) $id;
			if ($pid <= 0) {
				continue;
			}
			$pub = trim((string) get_post_meta($pid, self::META_HOSTED_PRODUCT_PUBLIC_ID, true));
			if ($pub !== '') {
				$map[$pub] = $pid;
			}
		}
		return $map;
	}

	private static function request_id(): string {
		try {
			return bin2hex(random_bytes(8));
		} catch (\Throwable $e) {
			return (string) wp_generate_password(16, false, false);
		}
	}
}