<?php
/**
 * Public product listing.
 *
 * @package HostKhata
 */

namespace HostKhata\Frontend;

defined( 'ABSPATH' ) || exit;

use HostKhata\Core\Hookable;
use HostKhata\Database\Repositories\ProductRepository;
use HostKhata\Domain\Catalog\BillingCycle;
use HostKhata\Domain\Catalog\PriceType;
use HostKhata\Domain\Catalog\ProductType;
use HostKhata\Security\Sanitizer;
use HostKhata\Settings\Settings;
use HostKhata\Support\View;

/**
 * The `[hostkhata_products]` shortcode: package cards or a comparison table.
 *
 * Attributes: `group` (group slug), `type` (product type, default hosting),
 * `view` (`cards` or `table`), `cycle` (billing cycle to show first, default
 * monthly), `columns` (1 to 4), `button` (text of the order button).
 *
 * @since 0.1.0
 */
final class ProductsShortcode implements Hookable {

	/**
	 * Products.
	 *
	 * @var ProductRepository
	 */
	private $products;

	/**
	 * Settings.
	 *
	 * @var Settings
	 */
	private $settings;

	/**
	 * Constructor.
	 *
	 * @param ProductRepository $products Products.
	 * @param Settings          $settings Settings.
	 */
	public function __construct( ProductRepository $products, Settings $settings ) {
		$this->products = $products;
		$this->settings = $settings;
	}

	/**
	 * {@inheritdoc}
	 */
	public function register(): void {
		add_shortcode( 'hostkhata_products', array( $this, 'render' ) );
	}

	/**
	 * Renders the shortcode.
	 *
	 * @since 0.1.0
	 *
	 * @param array<string, string>|string $attributes Shortcode attributes.
	 * @return string
	 */
	public function render( $attributes = array() ): string {
		$atts = shortcode_atts(
			array(
				'group'   => '',
				'type'    => ProductType::HOSTING,
				'view'    => 'cards',
				'cycle'   => BillingCycle::MONTHLY,
				'columns' => '3',
				'button'  => '',
			),
			is_array( $attributes ) ? $attributes : array(),
			'hostkhata_products'
		);

		$type    = Sanitizer::enum( $atts['type'], ProductType::all(), ProductType::HOSTING );
		$cycle   = Sanitizer::enum( $atts['cycle'], BillingCycle::all(), BillingCycle::MONTHLY );
		$view    = Sanitizer::enum( $atts['view'], array( 'cards', 'table' ), 'cards' );
		$columns = max( 1, min( 4, Sanitizer::absint( $atts['columns'] ) ) );
		$button  = '' !== trim( (string) $atts['button'] ) ? Sanitizer::text( $atts['button'] ) : __( 'Order now', 'hostkhata' );

		$items = array();

		foreach ( $this->products->public_listing( Sanitizer::key( $atts['group'] ), $type ) as $product ) {
			$items[] = $this->present( $product, $cycle );
		}

		wp_enqueue_style( 'hostkhata-products', HOSTKHATA_URL . 'assets/public/products.css', array(), HOSTKHATA_VERSION );

		return View::render(
			'portal/products',
			array(
				'view'     => $view,
				'columns'  => $columns,
				'button'   => $button,
				'products' => $items,
				'features' => $this->all_features( $items ),
			)
		);
	}

	/**
	 * Shapes a product for the template.
	 *
	 * @param array<string, mixed> $product Product from the repository.
	 * @param string               $cycle   Preferred billing cycle.
	 * @return array<string, mixed>
	 */
	private function present( array $product, string $cycle ): array {
		$primary = $this->primary_price( $product, $cycle );
		$others  = array();

		foreach ( $product['prices'] as $price ) {
			if ( null !== $primary && $price['id'] === $primary['id'] ) {
				continue;
			}

			$others[] = array(
				'label'     => PriceType::RECURRING === $price['price_type'] ? BillingCycle::label( $price['billing_cycle'] ) : $this->domain_label( $price ),
				'formatted' => $this->settings->format_money( $price['price'] ),
			);
		}

		return array(
			'name'        => $product['name'],
			'slug'        => $product['slug'],
			'description' => $product['description'],
			'features'    => $product['features'],
			'popular'     => $product['is_popular'],
			'price'       => null === $primary ? '' : $this->settings->format_money( $primary['price'] ),
			'per'         => null === $primary ? '' : $this->per_label( $product, $primary ),
			'setup'       => null !== $primary && $primary['setup_fee'] > 0 ? $this->settings->format_money( $primary['setup_fee'] ) : '',
			'others'      => $others,
			'order_url'   => $this->order_url( $product['slug'], null === $primary ? '' : $primary['billing_cycle'] ),
		);
	}

	/**
	 * The price to show first: the preferred cycle, or the cheapest per month.
	 *
	 * @param array<string, mixed> $product Product.
	 * @param string               $cycle   Preferred cycle.
	 * @return array<string, mixed>|null
	 */
	private function primary_price( array $product, string $cycle ): ?array {
		$candidates = array_values(
			array_filter(
				$product['prices'],
				static function ( array $price ) {
					return in_array( $price['price_type'], array( PriceType::RECURRING, PriceType::REGISTER ), true );
				}
			)
		);

		if ( array() === $candidates ) {
			return null;
		}

		foreach ( $candidates as $price ) {
			if ( $price['billing_cycle'] === $cycle ) {
				return $price;
			}
		}

		usort(
			$candidates,
			static function ( array $a, array $b ) {
				$per_a = $a['price'] / max( 1, $a['period_months'] );
				$per_b = $b['price'] / max( 1, $b['period_months'] );

				return $per_a <=> $per_b;
			}
		);

		return $candidates[0];
	}

	/**
	 * Text after the main price.
	 *
	 * @param array<string, mixed> $product Product.
	 * @param array<string, mixed> $price   Price row.
	 * @return string
	 */
	private function per_label( array $product, array $price ): string {
		if ( ProductType::DOMAIN === $product['type'] ) {
			return $this->domain_period( (int) $price['period_months'] );
		}

		return BillingCycle::per( $price['billing_cycle'] );
	}

	/**
	 * A label for a domain price row, for example "Renew, 1 year".
	 *
	 * @param array<string, mixed> $price Price row.
	 * @return string
	 */
	private function domain_label( array $price ): string {
		$names = array(
			PriceType::REGISTER => __( 'Register', 'hostkhata' ),
			PriceType::RENEW    => __( 'Renew', 'hostkhata' ),
			PriceType::TRANSFER => __( 'Transfer', 'hostkhata' ),
		);

		return ( $names[ $price['price_type'] ] ?? $price['price_type'] ) . ', ' . $this->domain_period( (int) $price['period_months'] );
	}

	/**
	 * "1 year", "2 years".
	 *
	 * @param int $months Months.
	 * @return string
	 */
	private function domain_period( int $months ): string {
		$years = (int) ( $months / 12 );

		/* translators: %d: number of years. */
		return sprintf( _n( '%d year', '%d years', $years, 'hostkhata' ), $years );
	}

	/**
	 * Link to the order page for a package, or an empty string when no order page is set.
	 *
	 * @param string $slug  Product slug.
	 * @param string $cycle Billing cycle.
	 * @return string
	 */
	private function order_url( string $slug, string $cycle ): string {
		$page_id = (int) $this->settings->get( 'order_page_id' );
		$url     = $page_id > 0 ? get_permalink( $page_id ) : '';

		if ( ! $url ) {
			return '';
		}

		return add_query_arg(
			array_filter(
				array(
					'package' => $slug,
					'cycle'   => $cycle,
				)
			),
			$url
		);
	}

	/**
	 * Every feature that appears in any product, for the comparison table rows.
	 *
	 * @param array<int, array<string, mixed>> $items Presented products.
	 * @return string[]
	 */
	private function all_features( array $items ): array {
		$features = array();

		foreach ( $items as $item ) {
			$features = array_merge( $features, $item['features'] );
		}

		return array_values( array_unique( $features ) );
	}
}