<?php
/**
 * Public card endpoint: one rendered feature.
 *
 * @package Mapsemble
 */

namespace Mapsemble\Rest;

use Mapsemble\CardRenderer;
use Mapsemble\Feed\FeedQuery;
use Mapsemble\Feed\ResponseCache;
use Mapsemble\MapConfig;
use Mapsemble\MapConfigRepository;
use WP_Error;
use WP_REST_Request;
use WP_REST_Response;

/**
 * GET /wp-json/mapsemble/v1/feature
 *
 * Returns `{html, css: [], js: {head, foot}, data}` for one post —
 * the card the widget injects into its shadow DOM. An unresolvable
 * map yields the empty shape (200, Drupal parity); a missing,
 * foreign-type, or unpublished post yields 404 so private content
 * cannot be probed.
 */
class FeatureController {

	use HostedMapRefusal;

	private const ALLOWED_LOCATIONS = array(
		'listDesktop',
		'listMobile',
		'selectedDesktop',
		'selectedMobile',
	);

	/**
	 * Config repository.
	 *
	 * @var MapConfigRepository
	 */
	private MapConfigRepository $repository;

	/**
	 * Card renderer.
	 *
	 * @var CardRenderer
	 */
	private CardRenderer $renderer;

	/**
	 * Feed-settings query translator.
	 *
	 * @var FeedQuery
	 */
	private FeedQuery $feed_query;

	/**
	 * Response cache.
	 *
	 * @var ResponseCache
	 */
	private ResponseCache $cache;

	/**
	 * Constructor.
	 *
	 * @param MapConfigRepository $repository Config repository.
	 * @param CardRenderer        $renderer   Card renderer.
	 * @param FeedQuery           $feed_query Feed-settings query translator.
	 * @param ResponseCache       $cache      Response cache (the instance Plugin registered).
	 */
	public function __construct( MapConfigRepository $repository, CardRenderer $renderer, FeedQuery $feed_query, ResponseCache $cache ) {
		$this->repository = $repository;
		$this->renderer   = $renderer;
		$this->feed_query = $feed_query;
		$this->cache      = $cache;
	}

	/**
	 * Registers the REST route.
	 */
	public function register_routes(): void {
		register_rest_route(
			'mapsemble/v1',
			'/feature',
			array(
				'methods'             => 'GET',
				'callback'            => array( $this, 'handle' ),
				'permission_callback' => '__return_true',
				'args'                => array(
					'mapId'    => array( 'type' => 'string' ),
					'id'       => array( 'type' => 'string' ),
					'language' => array( 'type' => 'string' ),
					'location' => array( 'type' => 'string' ),
					'filters'  => array( 'type' => 'string' ),
				),
			)
		);
	}

	/**
	 * Answers the request, from the cache when it can.
	 *
	 * Everything that can say 404 — the refusal, the post's existence,
	 * status, type and membership — runs in front of the cache, so an
	 * unpublished post vanishes at once rather than after a minute. Only
	 * the rendering is cached.
	 *
	 * @param WP_REST_Request $request The request.
	 * @return WP_REST_Response|WP_Error
	 */
	public function handle( WP_REST_Request $request ) {
		$config = $this->repository->find_by_map_id( (string) $request->get_param( 'mapId' ) );
		if ( null === $config ) {
			return $this->respond( '', array(), array() );
		}
		if ( $config->is_hosted() ) {
			// Cards for a hosted map are rendered by Mapsemble from its own
			// rows. Rendering one from a post here would answer about content
			// the map does not show.
			return $this->hosted_map_refusal();
		}

		$id = (string) $request->get_param( 'id' );
		if ( '' === $id || ! ctype_digit( $id ) ) {
			return new WP_Error( 'mapsemble_not_found', __( 'Feature not found.', 'mapsemble' ), array( 'status' => 404 ) );
		}
		$filters   = $this->feed_query->parse_filters( (string) $request->get_param( 'filters' ) );
		$card_post = get_post( (int) $id );
		if ( null === $card_post
			|| $card_post->post_type !== $config->post_type
			|| 'publish' !== $card_post->post_status
			// A post the feed would not list must not render a card either:
			// same 404 as a missing post, so excluded content cannot be probed.
			|| ! $this->feed_query->post_matches( $config, (int) $card_post->ID, $filters ) ) {
			return new WP_Error( 'mapsemble_not_found', __( 'Feature not found.', 'mapsemble' ), array( 'status' => 404 ) );
		}

		$raw_location = (string) $request->get_param( 'location' );
		$location     = in_array( $raw_location, self::ALLOWED_LOCATIONS, true ) ? $raw_location : null;

		// `filters` is not part of the key: it decides membership, which was
		// settled above, and plays no part in the rendering.
		return $this->cache->remember(
			'feature',
			$config,
			$request,
			array(
				'id'       => (int) $card_post->ID,
				'language' => (string) $request->get_param( 'language' ),
				'location' => (string) $location,
			),
			fn (): WP_REST_Response => $this->build( $config, $card_post, $location )
		);
	}

	/**
	 * Renders the card response.
	 *
	 * @param MapConfig   $config    The matched, site-fed map.
	 * @param \WP_Post    $card_post The admitted post.
	 * @param string|null $location  Validated card location, or null.
	 */
	private function build( MapConfig $config, \WP_Post $card_post, ?string $location ): WP_REST_Response {
		$html = $this->renderer->render( $card_post, $location, $config );

		$css_urls = array(
			add_query_arg( 'ver', MAPSEMBLE_VERSION, plugins_url( 'assets/css/card.css', MAPSEMBLE_PLUGIN_FILE ) ),
		);

		/**
		 * Filters the stylesheet URLs the widget adopts for this card.
		 *
		 * @param string[]           $css_urls  Absolute CSS URLs.
		 * @param \WP_Post           $card_post The post being rendered.
		 * @param \Mapsemble\MapConfig $config  The map config.
		 */
		$css_urls = (array) apply_filters( 'mapsemble_card_css_urls', $css_urls, $card_post, $config );

		/**
		 * Filters the free-form data object returned with the card.
		 *
		 * @param array               $data      Arbitrary data for custom widget code.
		 * @param \WP_Post            $card_post The post being rendered.
		 * @param \Mapsemble\MapConfig $config   The map config.
		 */
		$data = (array) apply_filters( 'mapsemble_card_data', array(), $card_post, $config );

		return $this->respond( $html, array_values( $css_urls ), $data );
	}

	/**
	 * Wraps the payload in the card response shape.
	 *
	 * @param string   $html HTML markup ('' when the map is unknown).
	 * @param string[] $css  Stylesheet URLs.
	 * @param array    $data Free-form data.
	 */
	private function respond( string $html, array $css, array $data ): WP_REST_Response {
		$response = new WP_REST_Response(
			array(
				'html' => $html,
				'css'  => $css,
				'js'   => array(
					'head' => '',
					'foot' => '',
				),
				'data' => (object) $data,
			)
		);
		$response->header( 'Access-Control-Allow-Origin', '*' );
		return $response;
	}
}