<?php
/**
 * Store facts: time zone, currency, and the "Reading your store" checklist.
 *
 * @package Askshelf
 */

declare( strict_types = 1 );

namespace Askshelf\Data;

use Automattic\WooCommerce\Utilities\OrderUtil;
use DateTimeImmutable;
use Throwable;

defined( 'ABSPATH' ) || exit;

/**
 * Store-level facts used by the admin page and the model's system prompt.
 */
final class Store {

	/**
	 * Context sent with every question so the model can resolve "last week".
	 *
	 * @return array{today: string, now: string, timezone: string, currency: string, currency_symbol: string, price_decimals: int, week_starts_on: int, locale: string}
	 */
	public static function context(): array {
		$now = new DateTimeImmutable( 'now', wp_timezone() );
		return array(
			'today'           => $now->format( 'Y-m-d' ),
			'now'             => $now->format( 'H:i' ),
			'timezone'        => wp_timezone_string(),
			'currency'        => get_woocommerce_currency(),
			'currency_symbol' => html_entity_decode( get_woocommerce_currency_symbol(), ENT_QUOTES, 'UTF-8' ),
			'price_decimals'  => wc_get_price_decimals(),
			'week_starts_on'  => (int) get_option( 'start_of_week', 1 ),
			'locale'          => str_replace( '_', '-', get_user_locale() ),
		);
	}

	/**
	 * Order meta table and its order-id column, for whichever order storage is authoritative.
	 *
	 * @return array{table: string, id_column: string}
	 */
	public static function order_meta_table(): array {
		global $wpdb;
		if ( class_exists( OrderUtil::class ) && OrderUtil::custom_orders_table_usage_is_enabled() ) {
			return array(
				'table'     => $wpdb->prefix . 'wc_orders_meta',
				'id_column' => 'order_id',
			);
		}
		return array(
			'table'     => $wpdb->postmeta,
			'id_column' => 'post_id',
		);
	}

	/**
	 * What Askshelf can read, with row counts, for the first-run checklist.
	 *
	 * @return array{items: list<array{key: string, label: string, detail: string, count: int|null}>, import_pending: array{orders: int, customers: int}|null}
	 */
	public static function checklist(): array {
		global $wpdb;
		$stats = $wpdb->prefix . 'wc_order_stats';

		// phpcs:disable WordPress.DB.DirectDatabaseQuery.DirectQuery, WordPress.DB.DirectDatabaseQuery.NoCaching -- Read-only counts on WooCommerce's Analytics tables.
		$orders    = (int) $wpdb->get_var( $wpdb->prepare( 'SELECT COUNT(*) FROM %i WHERE parent_id = 0', $stats ) );
		$refunds   = (int) $wpdb->get_var( $wpdb->prepare( 'SELECT COUNT(*) FROM %i WHERE parent_id > 0', $stats ) );
		$customers = (int) $wpdb->get_var( $wpdb->prepare( 'SELECT COUNT(*) FROM %i', $wpdb->prefix . 'wc_customer_lookup' ) );

		$meta            = self::order_meta_table();
		$first_attribute = $wpdb->get_var(
			$wpdb->prepare(
				'SELECT MIN(s.date_created) FROM %i s INNER JOIN %i m ON m.%i = s.order_id AND m.meta_key = %s WHERE s.parent_id = 0',
				$stats,
				$meta['table'],
				$meta['id_column'],
				'_wc_order_attribution_source_type'
			)
		);
		// phpcs:enable

		$products   = self::count_posts( 'product' );
		$variations = self::count_posts( 'product_variation' );
		$coupons    = self::count_posts( 'shop_coupon' );

		$attribution_detail = $first_attribute
			? sprintf(
				/* translators: %s: a date such as "March 2024". */
				__( 'since %s', 'askshelf' ),
				wp_date( 'F Y', (int) strtotime( (string) $first_attribute . ' ' . wp_timezone_string() ) )
			)
			: __( 'no attributed orders yet', 'askshelf' );

		$items = array(
			array(
				'key'    => 'orders',
				'label'  => __( 'Orders', 'askshelf' ),
				/* translators: %s: number of rows. */
				'detail' => sprintf( _n( '%s row', '%s rows', $orders, 'askshelf' ), number_format_i18n( $orders ) ),
				'count'  => $orders,
			),
			array(
				'key'    => 'refunds',
				'label'  => __( 'Refunds', 'askshelf' ),
				/* translators: %s: number of rows. */
				'detail' => sprintf( _n( '%s row', '%s rows', $refunds, 'askshelf' ), number_format_i18n( $refunds ) ),
				'count'  => $refunds,
			),
			array(
				'key'    => 'products',
				'label'  => __( 'Products and variations', 'askshelf' ),
				'detail' => number_format_i18n( $products + $variations ),
				'count'  => $products + $variations,
			),
			array(
				'key'    => 'customers',
				'label'  => __( 'Customers', 'askshelf' ),
				/* translators: %s: number of customers. */
				'detail' => sprintf( __( '%s, counted only', 'askshelf' ), number_format_i18n( $customers ) ),
				'count'  => $customers,
			),
			array(
				'key'    => 'coupons',
				'label'  => __( 'Coupons', 'askshelf' ),
				/* translators: %s: number of coupon codes. */
				'detail' => sprintf( _n( '%s code', '%s codes', $coupons, 'askshelf' ), number_format_i18n( $coupons ) ),
				'count'  => $coupons,
			),
			array(
				'key'    => 'attribution',
				'label'  => __( 'Order attribution', 'askshelf' ),
				'detail' => $attribution_detail,
				'count'  => null,
			),
		);

		return array(
			'items'          => $items,
			'import_pending' => self::import_pending(),
		);
	}

	/**
	 * Orders and customers Analytics has not imported yet, or null if unknown.
	 *
	 * @return array{orders: int, customers: int}|null
	 */
	private static function import_pending(): ?array {
		try {
			$result = Analytics::get( '/reports/import/totals', array( 'skip_existing' => true ) );
		} catch ( Throwable $e ) {
			return null;
		}
		$data = $result['data'];
		if ( ! is_array( $data ) ) {
			return null;
		}
		return array(
			'orders'    => (int) ( $data['orders'] ?? 0 ),
			'customers' => (int) ( $data['customers'] ?? 0 ),
		);
	}

	/**
	 * Published or private posts of a type.
	 *
	 * @param string $type Post type.
	 */
	private static function count_posts( string $type ): int {
		$counts = wp_count_posts( $type );
		return (int) ( $counts->publish ?? 0 ) + (int) ( $counts->private ?? 0 );
	}
}