<?php
/**
 * GET /modules.
 *
 * @package Transtrix
 */

namespace Transtrix\Rest\Controllers;

use Transtrix\Contracts\Module;
use Transtrix\Plugin;
use WP_REST_Response;

defined( 'ABSPATH' ) || exit;

/**
 * What the module grid renders from.
 */
class Modules extends Controller {

	/**
	 * Register routes.
	 *
	 * @return void
	 */
	public function register_routes(): void {
		register_rest_route(
			self::NAMESPACE_V1,
			'/modules',
			array(
				array(
					'methods'             => 'GET',
					'callback'            => array( $this, 'get_modules' ),
					'permission_callback' => array( $this, 'permission_check' ),
					'args'                => array(),
				),
			)
		);
	}

	/**
	 * Every registered module, available or not.
	 *
	 * @return WP_REST_Response
	 */
	public function get_modules(): WP_REST_Response {
		$modules = array();

		foreach ( Plugin::instance()->modules()->all() as $module ) {
			$modules[] = $this->prepare( $module );
		}

		return rest_ensure_response( $modules );
	}

	/**
	 * One module as the UI needs it.
	 *
	 * @param Module $module The module.
	 * @return array<string,mixed>
	 */
	private function prepare( Module $module ): array {
		$available = $module->is_available();

		// Only the types this user may export, so the picker never offers one
		// the export route would refuse.
		$allowed = function ( $type ) use ( $module ) {
			return $this->can_export_type( $module, (string) $type );
		};

		return array(
			'id'                   => $module->id(),
			'label'                => $module->label(),
			'available'            => $available,
			'source'               => $module->source(),
			'description'          => $module->description(),
			'post_types'           => array_values( array_filter( array_merge( $module->selectable_post_types(), array_keys( $module->payload_types() ) ), $allowed ) ),
			'payload_types'        => array_values( array_filter( array_keys( $module->payload_types() ), $allowed ) ),
			'dependent_post_types' => $module->dependent_post_types(),
			'taxonomies'           => $module->taxonomies(),
			'counts'               => $available ? array_merge( $module->counts(), $module->payload_counts() ) : array(),
			'type_labels'          => $this->type_labels( $module ),
		);
	}

	/**
	 * Registered names for every slug this module can show, so the UI prints
	 * the label WordPress already holds ("Trips", "Coupons") instead of a
	 * title-cased slug ("Wte Coupon").
	 *
	 * @param Module $module The module.
	 * @return array<string,string>
	 */
	private function type_labels( Module $module ): array {
		$labels = array();

		$post_types = array_merge( $module->selectable_post_types(), $module->dependent_post_types() );

		foreach ( $post_types as $slug ) {
			$object = get_post_type_object( $slug );

			if ( $object ) {
				$labels[ $slug ] = $object->labels->name;
			}
		}

		$labels = array_merge( $labels, $module->payload_types() );

		foreach ( $module->taxonomies() as $slug ) {
			$object = get_taxonomy( $slug );

			if ( $object ) {
				$labels[ $slug ] = $object->labels->name;
			}
		}

		return $labels;
	}
}