<?php

declare( strict_types=1 );

namespace Rooster\Modules\Rest;

defined( 'ABSPATH' ) || exit;

final class Suggest {

	public const NS    = 'rooster/v1';
	public const ROUTE = '/suggest';

	
	private const LIMITS = [ 'product' => 6, 'category' => 3, 'course' => 4, 'lesson' => 4, 'post' => 6, 'page' => 2 ];

	
	private const LIMITS_ALL = [ 'product' => 4, 'category' => 2, 'course' => 3, 'lesson' => 3, 'post' => 3, 'page' => 2 ];

	
	private const TYPES = [
		'learning' => [ 'rooster_course' => 'course', 'rooster_lesson' => 'lesson' ],
		'blog'     => [ 'post' => 'post' ],
		'all'      => [ 'rooster_course' => 'course', 'rooster_lesson' => 'lesson', 'post' => 'post', 'page' => 'page' ],
	];

	public static function boot(): void {
		add_action( 'rest_api_init', [ self::class, 'routes' ] );
	}

	public static function routes(): void {
		register_rest_route( self::NS, self::ROUTE, [
			'methods'             => 'GET',
			'callback'            => [ self::class, 'answer' ],
			'permission_callback' => '__return_true',
			'args'                => [
				'q'     => [ 'type' => 'string', 'required' => true, 'minLength' => 2, 'maxLength' => 80 ],
				'scope' => [ 'type' => 'string', 'enum' => [ 'product', 'learning', 'blog', 'all' ], 'default' => 'product' ],
			],
		] );
	}

	public static function answer( \WP_REST_Request $request ): \WP_REST_Response {
		$q     = trim( preg_replace( '/\s+/u', ' ', wp_strip_all_tags( (string) $request['q'] ) ) ?? '' );
		$scope = (string) $request['scope'];
		if ( 'product' === $scope && ! self::has_products() ) {
			$scope = 'all';
		}
		$lang  = (string) ( apply_filters( 'wpml_current_language', null ) ?? ( function_exists( 'pll_current_language' ) ? pll_current_language() : '' ) );
		
		
		$shared = ! is_user_logged_in();
		$key    = md5( $q . '|' . $scope . '|' . $lang );
		$items  = $shared ? wp_cache_get( $key, 'rooster_suggest' ) : false;
		if ( ! is_array( $items ) ) {
			$items = mb_strlen( $q ) < 2 ? [] : self::items( $q, $scope );
			if ( $shared ) {
				wp_cache_set( $key, $items, 'rooster_suggest', 5 * MINUTE_IN_SECONDS );
			}
		}
		$types    = match ( $scope ) {
			'product'  => 'product',
			'learning' => array_values( array_filter( array_keys( self::TYPES['learning'] ), 'post_type_exists' ) ),
			'blog'     => 'post',
			default    => '',
		};
		$all      = add_query_arg( array_filter( [ 's' => rawurlencode( $q ), 'post_type' => $types ] ), home_url( '/' ) );
		$response = new \WP_REST_Response( [ 'q' => $q, 'scope' => $scope, 'items' => $items, 'all' => $all ] );
		$response->header( 'Cache-Control', $shared ? 'public, max-age=300' : 'private, no-store' );
		return $response;
	}

	
	public static function items( string $q, string $scope ): array {
		$items  = [];
		$limits = 'all' === $scope ? self::LIMITS_ALL : self::LIMITS;
		if ( in_array( $scope, [ 'product', 'all' ], true ) && self::has_products() ) {
			foreach ( self::posts( 'product', $q, $limits['product'], self::product_query_args() ) as $id ) {
				$product = wc_get_product( $id );
				if ( ! $product ) {
					continue;
				}
				$items[] = self::item( 'product', $id ) + self::price( (string) $product->get_price_html() );
			}
			$terms = get_terms( [ 'taxonomy' => 'product_cat', 'name__like' => $q, 'number' => $limits['category'], 'hide_empty' => true, 'orderby' => 'count', 'order' => 'DESC' ] );
			foreach ( is_array( $terms ) ? $terms : [] as $term ) {
				$link = get_term_link( $term );
				if ( is_string( $link ) ) {
					$item  = [ 'type' => 'category', 'title' => self::text( $term->name ), 'url' => $link, 'count' => (int) $term->count ];
					$thumb = (int) get_term_meta( $term->term_id, 'thumbnail_id', true );
					$image = $thumb ? wp_get_attachment_image_src( $thumb, 'woocommerce_gallery_thumbnail' ) : false;
					$items[] = $image ? $item + [ 'image' => (string) $image[0] ] : $item;
				}
			}
		}
		foreach ( self::TYPES[ $scope ] ?? [] as $post_type => $type ) {
			if ( ! post_type_exists( $post_type ) ) {
				continue;
			}
			foreach ( self::posts( $post_type, $q, $limits[ $type ], 'page' === $type ? self::shop_pages() : [] ) as $id ) {
				$items[] = self::item( $type, $id );
			}
		}
		
		return array_values( array_filter( (array) apply_filters( 'rooster/suggest/items', $items, $q, $scope ), static fn ( $item ) => is_array( $item ) && ! empty( $item['title'] ) && ! empty( $item['url'] ) ) );
	}

	
	private static function shop_pages(): array {
		$ids = function_exists( 'wc_get_page_id' ) ? array_filter( array_map( 'wc_get_page_id', [ 'cart', 'checkout', 'myaccount' ] ), static fn ( $id ) => $id > 0 ) : [];
		return $ids ? [ 'post__not_in' => array_values( $ids ) ] : [];
	}

	private static function has_products(): bool {
		return function_exists( 'wc_get_product' ) && post_type_exists( 'product' );
	}

	
	private static function product_query_args(): array {
		$hidden = function_exists( 'wc_get_product_visibility_term_ids' ) ? wc_get_product_visibility_term_ids() : [];
		$ids    = array_filter( [ $hidden['exclude-from-search'] ?? 0, 'yes' === get_option( 'woocommerce_hide_out_of_stock_items' ) ? ( $hidden['outofstock'] ?? 0 ) : 0 ] );
		return $ids ? [ 'tax_query' => [ [ 'taxonomy' => 'product_visibility', 'field' => 'term_taxonomy_id', 'terms' => array_values( $ids ), 'operator' => 'NOT IN' ] ] ] : []; 
	}

	
	private static function posts( string $post_type, string $q, int $limit, array $extra = [] ): array {
		$query = new \WP_Query( $extra + [
			'post_type'              => $post_type,
			'post_status'            => 'publish',
			's'                      => $q,
			'posts_per_page'         => $limit,
			'fields'                 => 'ids',
			'no_found_rows'          => true,
			'ignore_sticky_posts'    => true,
			'update_post_term_cache' => false,
			'suppress_filters'       => false,
		] );
		return array_map( 'intval', $query->posts );
	}

	private static function item( string $type, int $id ): array {
		$item  = [ 'type' => $type, 'title' => self::text( get_the_title( $id ) ), 'url' => (string) get_permalink( $id ) ];
		$thumb = get_post_thumbnail_id( $id );
		$image = $thumb ? wp_get_attachment_image_src( (int) $thumb, 'product' === $type && has_image_size( 'woocommerce_gallery_thumbnail' ) ? 'woocommerce_gallery_thumbnail' : 'thumbnail' ) : false;
		if ( $image ) {
			$item['image'] = (string) $image[0];
		}
		return $item;
	}

	
	public static function price( string $html ): array {
		$html = (string) preg_replace( '#<span class="screen-reader-text">.*?</span>#s', '', $html );
		$out  = [];
		if ( preg_match( '#<del[^>]*>(.*?)</del>#s', $html, $m ) ) {
			$out['was'] = self::text( $m[1] );
			$html       = str_replace( $m[0], '', $html );
		}
		return [ 'price' => self::text( $html ) ] + $out;
	}

	
	private static function text( string $html ): string {
		$text = html_entity_decode( wp_strip_all_tags( $html ), ENT_QUOTES | ENT_HTML5, 'UTF-8' );
		return trim( (string) preg_replace( '/\s+/u', ' ', $text ) );
	}
}