<?php
namespace Strikewise\Pricing;

defined( 'ABSPATH' ) || exit;

/**
 * Exemption of § 11 Abs. 4 Nr. 2 PAngV: perishable goods or goods with a short
 * shelf life that are reduced because they are about to spoil or expire.
 *
 * Marked per product or variation. While such a product is reduced, Strikewise
 * shows no lowest price and does not correct the strike-through price, but
 * names the reason instead, because the exemption requires that customers can
 * recognise it.
 */
final class Perishable {

	const META = '_strikewise_perishable';

	public function register(): void {
		if ( is_admin() ) {
			add_action( 'woocommerce_product_options_pricing', array( $this, 'render_field' ) );
			add_action( 'woocommerce_admin_process_product_object', array( $this, 'save_product' ) );
			add_action( 'woocommerce_variation_options_pricing', array( $this, 'render_variation_field' ), 10, 3 );
			add_action( 'woocommerce_save_product_variation', array( $this, 'save_variation' ), 10, 2 );
		}
	}

	/**
	 * Whether the exemption applies right now: marked and reduced.
	 * Variations inherit the mark of their parent.
	 */
	public static function applies( \WC_Product $product ): bool {
		if ( ! self::is_marked( $product ) ) {
			return false;
		}
		return '' !== $product->get_sale_price( 'edit' ) && $product->is_on_sale( 'edit' );
	}

	public static function is_marked( \WC_Product $product ): bool {
		if ( 'yes' === $product->get_meta( self::META, true, 'edit' ) ) {
			return true;
		}
		$parent = $product->get_parent_id() ? wc_get_product( $product->get_parent_id() ) : null;
		return $parent instanceof \WC_Product && 'yes' === $parent->get_meta( self::META, true, 'edit' );
	}

	public function render_field(): void {
		global $product_object;
		woocommerce_wp_checkbox(
			array(
				'id'          => self::META,
				'label'       => __( 'Perishable', 'strikewise' ),
				'value'       => $product_object instanceof \WC_Product ? $product_object->get_meta( self::META, true, 'edit' ) : '',
				'cbvalue'     => 'yes',
				'description' => __( 'The sale price is reduced because the goods are about to spoil or reach their best-before date (§ 11 Abs. 4 PAngV). No lowest price is required; the shop shows the reason instead.', 'strikewise' ),
			)
		);
	}

	/**
	 * @param \WC_Product $product
	 */
	public function save_product( $product ): void {
		// phpcs:ignore WordPress.Security.NonceVerification -- WooCommerce verified the product form nonce.
		self::mark( $product, isset( $_POST[ self::META ] ) );
	}

	/**
	 * @param int      $loop
	 * @param array    $variation_data
	 * @param \WP_Post $variation
	 */
	public function render_variation_field( $loop, $variation_data, $variation ): void {
		$product = wc_get_product( $variation->ID );
		woocommerce_wp_checkbox(
			array(
				'id'            => self::META . '_' . $loop,
				'name'          => self::META . '[' . $loop . ']',
				'label'         => __( 'Perishable: reduced because it is about to spoil or expire', 'strikewise' ),
				'value'         => $product ? $product->get_meta( self::META, true, 'edit' ) : '',
				'cbvalue'       => 'yes',
				'wrapper_class' => 'form-row form-row-full',
			)
		);
	}

	/**
	 * @param int $variation_id
	 * @param int $loop
	 */
	public function save_variation( $variation_id, $loop ): void {
		$variation = wc_get_product( $variation_id );
		if ( ! $variation ) {
			return;
		}
		// phpcs:ignore WordPress.Security.NonceVerification -- WooCommerce verified the variation nonce.
		$marked = isset( $_POST[ self::META ][ $loop ] );
		$was    = 'yes' === $variation->get_meta( self::META, true, 'edit' );
		if ( $was !== $marked ) {
			self::mark( $variation, $marked );
			$variation->save();
		}
	}

	private static function mark( \WC_Product $product, bool $marked ): void {
		if ( $marked ) {
			$product->update_meta_data( self::META, 'yes' );
		} else {
			$product->delete_meta_data( self::META );
		}
	}

	public static function text(): string {
		$text = trim( (string) get_option( 'strikewise_perishable_text', '' ) );
		return '' === $text ? __( 'Reduced because of a short remaining shelf life', 'strikewise' ) : $text;
	}

	/**
	 * Settings row for the notice text, added to the display group.
	 *
	 * @return array<string,mixed>
	 */
	public static function setting(): array {
		return array(
			'title'       => __( 'Perishable goods', 'strikewise' ),
			'desc'        => __( 'Shown instead of the lowest price for reduced products marked as perishable.', 'strikewise' ),
			'id'          => 'strikewise_perishable_text',
			'type'        => 'text',
			'default'     => '',
			'placeholder' => __( 'Reduced because of a short remaining shelf life', 'strikewise' ),
			'css'         => 'min-width: 400px;',
		);
	}
}