<?php
/**
 * Designer on the product page.
 *
 * @package Eazign
 */

defined( 'ABSPATH' ) || exit;

/**
 * Puts the "Design now" button on designer products (classic themes via the
 * add-to-cart hook, block themes via the add-to-cart blocks, anywhere via
 * the [eazign_designer] shortcode) and serves the editor configuration.
 */
class Eazign_Frontend {

	const META = '_eazign_designer';

	/**
	 * Whether the button was printed on this page already.
	 *
	 * @var array
	 */
	private static $printed = array();

	/**
	 * Hooks.
	 */
	public static function init() {
		add_action( 'woocommerce_before_add_to_cart_button', array( __CLASS__, 'print_in_form' ), 5 );
		add_filter( 'render_block_woocommerce/add-to-cart-with-options', array( __CLASS__, 'append_to_block' ), 10, 2 );
		add_filter( 'render_block_woocommerce/add-to-cart-form', array( __CLASS__, 'append_to_block' ), 10, 2 );
		add_shortcode( 'eazign_designer', array( __CLASS__, 'shortcode' ) );
		add_action( 'rest_api_init', array( __CLASS__, 'routes' ) );
		add_action( 'wp_enqueue_scripts', array( __CLASS__, 'register_assets' ) );
		add_filter( 'body_class', array( __CLASS__, 'body_class' ) );
	}

	/**
	 * Marks designer product pages, so the normal add-to-cart button is
	 * hidden from the first paint on (not only once the loader ran).
	 *
	 * @param array $classes Body classes.
	 * @return array
	 */
	public static function body_class( $classes ) {
		if ( is_product() && Eazign_Client::is_connected() && self::is_designer_product( wc_get_product( get_queried_object_id() ) ) ) {
			$classes[] = 'eazign-product';
		}
		return $classes;
	}

	/**
	 * Whether a product is set up for the designer.
	 *
	 * @param WC_Product|null $product Product.
	 * @return bool
	 */
	public static function is_designer_product( $product ) {
		return $product instanceof WC_Product && $product->is_type( 'variable' ) && '1' === (string) $product->get_meta( self::META );
	}

	/**
	 * Scripts, enqueued only where the button is shown.
	 */
	public static function register_assets() {
		wp_register_style( 'eazign', EAZIGN_URL . 'assets/css/frontend.css', array(), EAZIGN_VERSION );
		wp_register_script( 'eazign-loader', EAZIGN_URL . 'assets/js/loader.js', array(), EAZIGN_VERSION, true );
		wp_localize_script(
			'eazign-loader',
			'eazignData',
			array(
				'configUrl' => esc_url_raw( rest_url( 'eazign/v1/config' ) ),
				'cartUrl'   => esc_url_raw( WC_AJAX::get_endpoint( 'eazign_add_to_cart' ) ),
				'nonce'     => wp_create_nonce( 'eazign_cart' ),
				'locale'    => substr( get_locale(), 0, 2 ),
				'error'     => __( 'The designer could not be loaded. Please try again later.', 'eazign' ),
			)
		);
		// Styles in the head on designer product pages (no flash of the normal button).
		if ( is_product() && Eazign_Client::is_connected() && self::is_designer_product( wc_get_product( get_queried_object_id() ) ) ) {
			wp_enqueue_style( 'eazign' );
		}
	}

	/**
	 * Classic add-to-cart form.
	 */
	public static function print_in_form() {
		global $product;
		echo self::markup( $product ); // phpcs:ignore WordPress.Security.EscapeOutput.OutputNotEscaped -- escaped in markup().
	}

	/**
	 * Block themes: after the add-to-cart block (if the form hook did not run).
	 *
	 * @param string $content Block HTML.
	 * @param array  $block   Block.
	 * @return string
	 */
	public static function append_to_block( $content, $block ) {
		$product = wc_get_product( get_the_ID() );
		return $content . self::markup( $product );
	}

	/**
	 * Shortcode [eazign_designer id="123"].
	 *
	 * @param array $atts Attributes.
	 * @return string
	 */
	public static function shortcode( $atts ) {
		$atts = shortcode_atts( array( 'id' => get_the_ID() ), $atts, 'eazign_designer' );
		return self::markup( wc_get_product( (int) $atts['id'] ) );
	}

	/**
	 * Button and product data for the loader.
	 *
	 * @param WC_Product|null $product Product.
	 * @return string
	 */
	public static function markup( $product ) {
		if ( ! self::is_designer_product( $product ) || ! Eazign_Client::is_connected() || isset( self::$printed[ $product->get_id() ] ) ) {
			return '';
		}
		self::$printed[ $product->get_id() ] = true;
		wp_enqueue_style( 'eazign' );
		wp_enqueue_script( 'eazign-loader' );
		return sprintf(
			'<div class="eazign" data-eazign data-product-id="%1$d" hidden><button type="button" class="button alt wp-element-button eazign-open">%2$s</button><p class="eazign-hint">%3$s</p><script type="application/json" data-eazign-product>%4$s</script></div>',
			$product->get_id(),
			esc_html__( 'Design now', 'eazign' ),
			esc_html__( 'Add your text, images and motifs – we print exactly what you see.', 'eazign' ),
			wp_json_encode( self::product_json( $product ), JSON_HEX_TAG | JSON_HEX_AMP | JSON_UNESCAPED_UNICODE )
		);
	}

	/**
	 * Product in the format the editor expects (options and variants with
	 * option values in attribute order, prices in cents as displayed).
	 *
	 * @param WC_Product_Variable $product Product.
	 * @return array
	 */
	public static function product_json( $product ) {
		$attributes = $product->get_variation_attributes();
		$names      = array_keys( $attributes );
		$variants   = array();
		foreach ( $product->get_children() as $child_id ) {
			$variation = wc_get_product( $child_id );
			if ( ! $variation || ! $variation->exists() || 'publish' !== $variation->get_status() ) {
				continue;
			}
			$values = array();
			$chosen = $variation->get_variation_attributes();
			foreach ( $names as $name ) {
				$value    = $chosen[ 'attribute_' . sanitize_title( $name ) ] ?? '';
				$values[] = taxonomy_exists( $name ) && $value ? ( get_term_by( 'slug', $value, $name )->name ?? $value ) : $value;
			}
			$variants[] = array(
				'id'        => $variation->get_id(),
				'title'     => implode( ' / ', $values ),
				'options'   => $values,
				'price'     => (int) round( (float) wc_get_price_to_display( $variation ) * 100 ),
				'available' => $variation->is_purchasable() && $variation->is_in_stock(),
			);
		}
		return array(
			'id'       => $product->get_id(),
			'title'    => $product->get_name(),
			'options'  => array_map(
				function ( $name ) use ( $product ) {
					return wc_attribute_label( $name, $product );
				},
				$names
			),
			'variants' => $variants,
			'currency' => get_woocommerce_currency(),
		);
	}

	/**
	 * REST route for the loader.
	 */
	public static function routes() {
		register_rest_route(
			'eazign/v1',
			'/config',
			array(
				'methods'             => 'GET',
				'permission_callback' => '__return_true',
				'callback'            => array( __CLASS__, 'config' ),
				'args'                => array(
					'product' => array(
						'required'          => true,
						'sanitize_callback' => 'absint',
					),
				),
			)
		);
	}

	/**
	 * Editor configuration of a product (cached briefly; it carries a
	 * storefront token valid for six hours).
	 *
	 * @param WP_REST_Request $request Request.
	 * @return WP_REST_Response
	 */
	public static function config( $request ) {
		$product = wc_get_product( (int) $request['product'] );
		// Public endpoint: only published, non-protected designer products.
		if ( ! self::is_designer_product( $product ) || 'publish' !== $product->get_status() || post_password_required( $product->get_id() ) || ! Eazign_Client::is_connected() ) {
			return rest_ensure_response( array( 'enabled' => false ) );
		}
		$key    = 'eazign_config_' . $product->get_id();
		$config = get_transient( $key );
		if ( ! is_array( $config ) ) {
			$config = Eazign_Client::get( 'config?product=' . $product->get_id() );
			if ( is_wp_error( $config ) ) {
				return rest_ensure_response( array( 'enabled' => false ) );
			}
			set_transient( $key, $config, 10 * MINUTE_IN_SECONDS );
		}
		$response = rest_ensure_response( $config );
		$response->header( 'Cache-Control', 'no-store' );
		return $response;
	}
}