import {Container} from '../../di'
import {ResponseFactory} from './ResponseFactory'
import {Request} from '../lifecycle/Request'
import {ViewEngine} from '../../views/ViewEngine'

/**
 * Helper function that creates a new ViewResponseFactory to render the given view
 * with the specified data.
 * @param name
 * @param data
 */
export function view(name: string, data?: {[key: string]: any}): ViewResponseFactory {
    return new ViewResponseFactory(name, data)
}

/**
 * Helper function that creates a new ViewResponseFactory that redirects the user to
 * the given URL.
 * @param url
 */
export function redirectToGet(url: string): ViewResponseFactory {
    return view('@extollo:redirect', { redirectUrl: url })
}

/**
 * HTTP response factory that uses the ViewEngine service to render a view
 * and send it as HTML.
 */
export class ViewResponseFactory extends ResponseFactory {
    constructor(
        /** The name of the view to render. */
        public readonly viewName: string,
        /** Optional data that should be passed to the view engine as params. */
        public readonly data?: {[key: string]: any},
    ) {
        super()
    }

    public async write(request: Request): Promise<Request> {
        const viewEngine = <ViewEngine> Container.getContainer().make(ViewEngine)
        request.response.body = await viewEngine.renderByName(this.viewName, this.data || {})
        request.response.setHeader('Content-Type', 'text/html; charset=utf-8')
        return request
    }
}