<?php
/**
 * Products: the paygrab_product post type, its sale settings and the [paygrab_buy] shortcode.
 *
 * @package PAYGRAB
 */

defined( 'ABSPATH' ) || exit;

/**
 * Product post type, sale settings and the buy box.
 *
 * Products have no page of their own: the seller pastes [paygrab_buy id="N"] into any post.
 */
class Paygrab_Product {

	const TYPE = 'paygrab_product';

	/** Shortcode that shows the buy box. */
	const SHORTCODE = 'paygrab_buy';

	/** Tax rate of digital products in Japan (standard rate). */
	const TAX_RATE = 10;

	/**
	 * Hooks.
	 *
	 * @return void
	 */
	public static function init() {
		self::register();
		add_shortcode( self::SHORTCODE, array( __CLASS__, 'shortcode' ) );
		add_filter( 'wp_untrash_post_status', array( __CLASS__, 'untrash_status' ), 10, 3 );
	}

	/**
	 * A product restored from the Trash goes back to how it was (WordPress makes restored posts drafts).
	 *
	 * @param string $new_status      Status WordPress chose.
	 * @param int    $post_id         Post ID.
	 * @param string $previous_status Status before it was trashed.
	 * @return string
	 */
	public static function untrash_status( $new_status, $post_id, $previous_status ) {
		return self::TYPE === get_post_type( $post_id ) && $previous_status ? $previous_status : $new_status;
	}

	/**
	 * Register the post type.
	 *
	 * @return void
	 */
	public static function register() {
		if ( post_type_exists( self::TYPE ) ) {
			return;
		}
		register_post_type(
			self::TYPE,
			array(
				'labels'       => array(
					'name'               => __( 'Products', 'paygrab' ),
					'singular_name'      => __( 'Product', 'paygrab' ),
					'add_new'            => __( 'Add new product', 'paygrab' ),
					'add_new_item'       => __( 'Add new product', 'paygrab' ),
					'edit_item'          => __( 'Edit product', 'paygrab' ),
					'new_item'           => __( 'New product', 'paygrab' ),
					'view_item'          => __( 'View product', 'paygrab' ),
					'search_items'       => __( 'Search products', 'paygrab' ),
					'not_found'          => __( 'No products found.', 'paygrab' ),
					'not_found_in_trash' => __( 'No products found in Trash.', 'paygrab' ),
					'all_items'          => __( 'Products', 'paygrab' ),
					'menu_name'          => __( 'Products', 'paygrab' ),
				),
				'public'              => false,
				'publicly_queryable'  => false,
				'exclude_from_search' => true,
				'has_archive'         => false,
				'rewrite'             => false,
				'query_var'           => false,
				'show_ui'             => true,
				'show_in_menu'        => false,
				'show_in_nav_menus'   => false,
				'show_in_rest'        => false,
				'supports'            => array( 'title', 'excerpt' ),
				// Only people who manage the shop (administrators) can see or change products.
				'map_meta_cap'        => true,
				'capabilities'        => array(
					'edit_posts'             => 'manage_options',
					'edit_others_posts'      => 'manage_options',
					'edit_private_posts'     => 'manage_options',
					'edit_published_posts'   => 'manage_options',
					'publish_posts'          => 'manage_options',
					'read_private_posts'     => 'manage_options',
					'delete_posts'           => 'manage_options',
					'delete_others_posts'    => 'manage_options',
					'delete_private_posts'   => 'manage_options',
					'delete_published_posts' => 'manage_options',
					'create_posts'           => 'manage_options',
				),
			)
		);
	}

	/**
	 * Sale settings of a product.
	 *
	 * @param int $product_id Product ID.
	 * @return array{id:int,price:int,tax_rate:int,file:array|null,limit:int,days:int,on_sale:bool,image:int}
	 */
	public static function data( $product_id ) {
		$product_id = (int) $product_id;
		$file       = get_post_meta( $product_id, '_paygrab_file', true );
		$data       = array(
			'id'       => $product_id,
			'price'    => (int) get_post_meta( $product_id, '_paygrab_price', true ),
			'tax_rate' => self::TAX_RATE,
			'file'     => is_array( $file ) && ! empty( $file['path'] ) ? $file : null,
			'limit'    => metadata_exists( 'post', $product_id, '_paygrab_download_limit' ) ? max( 0, (int) get_post_meta( $product_id, '_paygrab_download_limit', true ) ) : 5,
			'days'     => metadata_exists( 'post', $product_id, '_paygrab_download_days' ) ? max( 0, (int) get_post_meta( $product_id, '_paygrab_download_days', true ) ) : 30,
			'on_sale'  => '1' === (string) get_post_meta( $product_id, '_paygrab_on_sale', true ),
			'image'    => (int) get_post_meta( $product_id, '_paygrab_image', true ),
		);
		/**
		 * Filters a product's sale settings.
		 *
		 * @param array $data       Settings.
		 * @param int   $product_id Product ID.
		 */
		return apply_filters( 'paygrab_product_data', $data, $product_id );
	}

	/**
	 * What a product still needs before it can be sold.
	 *
	 * @param int $product_id Product ID.
	 * @return string[] Any of 'name', 'price', 'file'.
	 */
	public static function missing( $product_id ) {
		$data    = self::data( $product_id );
		$missing = array();
		if ( '' === trim( (string) get_post_field( 'post_title', $product_id ) ) ) {
			$missing[] = 'name';
		}
		if ( $data['price'] <= 0 ) {
			$missing[] = 'price';
		}
		if ( ! $data['file'] || ! Paygrab_Files::path( $data['file']['path'] ) ) {
			$missing[] = 'file';
		}
		return $missing;
	}

	/**
	 * Labels of the missing items.
	 *
	 * @return array<string,string>
	 */
	public static function missing_labels() {
		return array(
			'name'  => __( 'product name', 'paygrab' ),
			'price' => __( 'price', 'paygrab' ),
			'file'  => __( 'file', 'paygrab' ),
		);
	}

	/**
	 * Whether a product can be bought now.
	 *
	 * @param int $product_id Product ID.
	 * @return bool
	 */
	public static function purchasable( $product_id ) {
		$post = get_post( $product_id );
		if ( ! $post || self::TYPE !== $post->post_type || 'publish' !== $post->post_status ) {
			return false;
		}
		$ok = self::data( $product_id )['on_sale'] && ! self::missing( $product_id );
		/**
		 * Filters whether a product can be bought.
		 *
		 * @param bool $ok         Purchasable.
		 * @param int  $product_id Product ID.
		 */
		return (bool) apply_filters( 'paygrab_product_purchasable', $ok, $product_id );
	}

	/**
	 * Price charged for one unit (Pro applies sales and coupons here).
	 *
	 * @param int $product_id Product ID.
	 * @return int
	 */
	public static function line_price( $product_id ) {
		$data = self::data( $product_id );
		return max( 0, (int) apply_filters( 'paygrab_line_price', $data['price'], $product_id ) );
	}

	/**
	 * [paygrab_buy id="123"] shortcode.
	 *
	 * @param array $atts Attributes.
	 * @return string
	 */
	public static function shortcode( $atts ) {
		$atts = shortcode_atts( array( 'id' => 0 ), $atts, self::SHORTCODE );
		return self::buy_box( (int) $atts['id'], array( 'source' => paygrab_current_source() ) );
	}

	/**
	 * Shortcode text for a product.
	 *
	 * @param int $product_id Product ID.
	 * @return string
	 */
	public static function shortcode_text( $product_id ) {
		return sprintf( '[%s id="%d"]', self::SHORTCODE, (int) $product_id );
	}

	/**
	 * The buy box for a product, in the state that fits the visitor.
	 *
	 * @param int   $product_id Product ID.
	 * @param array $args {
	 *     @type int   $source  Post the box is shown in (the buyer comes back to it).
	 *     @type array $preview Values to show instead of the saved ones (admin preview):
	 *                          title, excerpt, data, state (buy|pending|owned|unavailable).
	 * }
	 * @return string HTML.
	 */
	public static function buy_box( $product_id, $args = array() ) {
		$args    = wp_parse_args( $args, array( 'source' => 0, 'preview' => null ) );
		$preview = is_array( $args['preview'] ) ? $args['preview'] : null;
		$post    = $product_id ? get_post( $product_id ) : null;
		$exists  = $post && self::TYPE === $post->post_type && 'publish' === $post->post_status;
		if ( ! $exists && ! $preview ) {
			// A wrong number or a product in the Trash shows nothing to visitors.
			return current_user_can( 'manage_options' ) ? paygrab_get_template( 'buy-box-missing', array( 'product_id' => (int) $product_id ) ) : '';
		}
		Paygrab_Frontend::enqueue();

		if ( $preview ) {
			$vars = self::preview_vars( $product_id, $preview );
		} else {
			$vars = self::visitor_vars( $post, (int) $args['source'] );
		}
		return paygrab_get_template( 'buy-box', $vars );
	}

	/**
	 * Template variables for the real visitor.
	 *
	 * @param WP_Post $post   Product.
	 * @param int     $source Post the box is shown in.
	 * @return array
	 */
	private static function visitor_vars( WP_Post $post, $source ) {
		$data    = self::data( $post->ID );
		$user_id = get_current_user_id();
		$state   = 'buy';
		$order   = null;
		$access  = null;

		if ( $user_id ) {
			$access = Paygrab_Downloads::active_for( $user_id, $post->ID );
			if ( $access ) {
				$state = 'owned';
			} else {
				$order = Paygrab_Orders::pending_for( $user_id, $post->ID );
				if ( $order ) {
					$state = 'pending';
				}
			}
		}
		if ( 'buy' === $state && ! self::purchasable( $post->ID ) ) {
			$state = 'unavailable';
		}
		$access_order = $access ? Paygrab_Orders::get( $access->order_id ) : null;

		// An order awaiting payment: a bank transfer the buyer makes, or an online payment not finished yet.
		$pay = array(
			'kind' => 'transfer',
			'url'  => '',
		);
		if ( $order ) {
			$gateway = Paygrab_Gateways::get( $order->gateway );
			$online  = $gateway && $gateway->confirms_payments();
			$pay     = array(
				'kind' => $online ? 'online' : 'transfer',
				'url'  => $online ? Paygrab_Checkout::complete_url( $order ) : paygrab_mypage_url( $order->order_number ),
			);
			/**
			 * Filters how the buy box speaks about an order awaiting payment.
			 *
			 * kind "transfer": "Please pay by …" and "See where to pay" (bank transfers the buyer makes).
			 * kind "online":   "The payment is not complete yet" and "Continue to payment".
			 * PAYGRAB Pro returns "transfer" for Stripe's bank transfer.
			 *
			 * @param array{kind:string,url:string} $pay     Kind and where the button goes.
			 * @param Paygrab_Order                   $order   Order.
			 * @param Paygrab_Gateway|null            $gateway Gateway.
			 */
			$pay = wp_parse_args( (array) apply_filters( 'paygrab_buy_box_pending', $pay, $order, $gateway ), $pay );
		}

		return array(
			'title'        => get_the_title( $post ),
			'excerpt'      => self::excerpt( $post ),
			'data'         => $data,
			'state'        => $state,
			'price'        => self::line_price( $post->ID ),
			'deadline'     => $order && $order->pay_deadline ? paygrab_deadline( $order->pay_deadline ) : '',
			'left'         => $access ? Paygrab_Downloads::remaining( $access ) : null,
			'until'        => $access && $access->expires_at ? paygrab_short_date( $access->expires_at ) : '',
			'checkout_url' => Paygrab_Checkout::url( $post->ID, $source ),
			'order_url'    => (string) $pay['url'],
			'pending_kind' => 'online' === $pay['kind'] ? 'online' : 'transfer',
			'mypage_url'   => paygrab_mypage_url( $access_order ? $access_order->order_number : '' ),
			'law_url'      => paygrab_page_url( 'tokushoho' ),
			'gateways'     => Paygrab_Gateways::available(),
			'logged_in'    => (bool) $user_id,
			'image'        => self::image_html( $data['image'] ),
		);
	}

	/**
	 * The product image for the buy box. Where it goes depends on the design (paygrab.css).
	 *
	 * @param int|string $image Attachment ID, or 'sample' for the settings preview.
	 * @return string <img>, or '' when there is no usable image.
	 */
	public static function image_html( $image ) {
		if ( 'sample' === $image ) {
			return '<img src="' . esc_url( PAYGRAB_URL . 'assets/img/sample-cover.svg' ) . '" alt="" width="1200" height="900" loading="lazy" decoding="async">';
		}
		$image = (int) $image;
		if ( ! $image || ! wp_attachment_is_image( $image ) ) {
			return '';
		}
		/**
		 * Filters the image size used in the buy box.
		 *
		 * @param string $size  Image size name.
		 * @param int    $image Attachment ID.
		 */
		$size = (string) apply_filters( 'paygrab_buy_box_image_size', 'large', $image );
		// Some themes write a size into the image's style attribute (Twenty Twenty-One: height:66%),
		// which would beat the stylesheet; the box sets the size itself, so it is taken out here.
		$no_style = static function ( $attr ) {
			unset( $attr['style'] );
			return $attr;
		};
		add_filter( 'wp_get_attachment_image_attributes', $no_style, PHP_INT_MAX );
		$html = (string) wp_get_attachment_image(
			$image,
			$size,
			false,
			array(
				'loading' => 'lazy',
				'sizes'   => '(max-width: 600px) 100vw, 600px',
			)
		);
		remove_filter( 'wp_get_attachment_image_attributes', $no_style, PHP_INT_MAX );
		return $html;
	}

	/**
	 * Template variables for the admin preview (unsaved values, example dates).
	 *
	 * @param int   $product_id Product ID (0 for a new product).
	 * @param array $preview    Values.
	 * @return array
	 */
	private static function preview_vars( $product_id, array $preview ) {
		$data  = wp_parse_args( (array) ( $preview['data'] ?? array() ), self::data( $product_id ) );
		$state = in_array( $preview['state'] ?? '', array( 'buy', 'pending', 'owned', 'unavailable' ), true ) ? $preview['state'] : 'buy';
		if ( empty( $data['on_sale'] ) && 'buy' === $state ) {
			$state = 'unavailable';
		}
		$days = (int) Paygrab_Settings::get( 'pay_days' );
		return array(
			'title'        => (string) ( $preview['title'] ?? '' ),
			'excerpt'      => (string) ( $preview['excerpt'] ?? '' ),
			'data'         => $data,
			'state'        => $state,
			'price'        => (int) $data['price'],
			'deadline'     => paygrab_deadline( paygrab_now( max( 1, $days ) * DAY_IN_SECONDS ) ),
			'left'         => $data['limit'] > 0 ? (int) $data['limit'] : null,
			'until'        => $data['days'] > 0 ? paygrab_short_date( paygrab_now( (int) $data['days'] * DAY_IN_SECONDS ) ) : '',
			'checkout_url' => '#',
			'order_url'    => '#',
			'pending_kind' => 'transfer',
			'mypage_url'   => '#',
			'law_url'      => paygrab_page_url( 'tokushoho' ),
			'gateways'     => Paygrab_Gateways::available(),
			'logged_in'    => true,
			'image'        => self::image_html( $data['image'] ),
		);
	}

	/**
	 * The one-line description.
	 *
	 * @param WP_Post|int $post Product.
	 * @return string
	 */
	public static function excerpt( $post ) {
		$post = get_post( $post );
		return $post ? self::clean_excerpt( (string) $post->post_excerpt ) : '';
	}

	/**
	 * Clean the one-line description: any length, line breaks kept (shown as they are in the buy box),
	 * runs of half-width spaces and tabs made single (full-width spaces are kept), runs of empty lines made single.
	 *
	 * @param string $text Text.
	 * @return string
	 */
	public static function clean_excerpt( $text ) {
		$text = sanitize_textarea_field( str_replace( array( "\r\n", "\r" ), "\n", (string) $text ) );
		$text = (string) preg_replace( array( '/[ \t]+/', '/ *\n */', '/\n{3,}/' ), array( ' ', "\n", "\n\n" ), $text );
		return trim( $text );
	}

	/**
	 * Posts that contain the shortcode of a product.
	 *
	 * @param int $product_id Product ID.
	 * @param int $limit      Most posts to return.
	 * @return WP_Post[]
	 */
	public static function used_in( $product_id, $limit = 20 ) {
		global $wpdb;
		$types = array_values( array_diff( get_post_types( array( 'public' => true ) ), array( 'attachment' ) ) );
		if ( ! $types ) {
			return array();
		}
		$id    = (int) $product_id;
		$in    = implode( ',', array_fill( 0, count( $types ), '%s' ) );
		$likes = array();
		foreach ( array( 'id="' . $id . '"', "id='" . $id . "'", 'id=' . $id . ']', 'id=' . $id . ' ' ) as $needle ) {
			$likes[] = '%' . $wpdb->esc_like( '[' . self::SHORTCODE . ' ' ) . '%' . $wpdb->esc_like( $needle ) . '%';
		}
		// phpcs:ignore WordPress.DB.DirectDatabaseQuery, WordPress.DB.PreparedSQLPlaceholders.UnfinishedPrepare, WordPress.DB.PreparedSQLPlaceholders.ReplacementsWrongNumber, WordPress.DB.PreparedSQL.InterpolatedNotPrepared -- $in is a list of %s placeholders, one for each post type.
		$ids = $wpdb->get_col( $wpdb->prepare( "SELECT ID FROM {$wpdb->posts} WHERE post_type IN ($in) AND post_status IN ('publish','future','draft','pending','private') AND ( post_content LIKE %s OR post_content LIKE %s OR post_content LIKE %s OR post_content LIKE %s ) ORDER BY post_modified DESC LIMIT %d", array_merge( $types, $likes, array( (int) $limit ) ) ) );
		return array_values( array_filter( array_map( 'get_post', $ids ) ) );
	}
}