import {HTTPKernel} from '../HTTPKernel'
import {MountActivatedRouteHTTPModule} from './MountActivatedRouteHTTPModule'
import {Request} from '../../lifecycle/Request'
import {ActivatedRoute} from '../../routing/ActivatedRoute'
import {ResponseObject} from '../../routing/Route'
import {AbstractResolvedRouteHandlerHTTPModule} from './AbstractResolvedRouteHandlerHTTPModule'

/**
 * HTTP Kernel module that executes the preflight handlers for the route.
 *
 * Usually, this is the pre middleware.
 */
export class ExecuteResolvedRoutePreflightHTTPModule extends AbstractResolvedRouteHandlerHTTPModule {
    public static register(kernel: HTTPKernel): void {
        kernel.register(this).after(MountActivatedRouteHTTPModule)
    }

    public async apply(request: Request): Promise<Request> {
        if ( request.hasInstance(ActivatedRoute) ) {
            const route = <ActivatedRoute> request.make(ActivatedRoute)
            const preflight = route.preflight

            for ( const handler of preflight ) {
                const result: ResponseObject = await handler(request)
                if ( typeof result !== 'undefined' ) {
                    await this.applyResponseObject(result, request)
                    request.response.blockingWriteback(true)
                }
            }
        }

        return request
    }
}