import * as Hapi from "hapi"
import {Handler} from "./Handler";
import {BaseRequestPayload, BaseResponsePayload, Request} from "./AbstractCall";
import {Service} from "./Service";
import {Logger} from "../Logger";

/**
 * Class to handle the actual Server
 */
export class MeetznowService{

    readonly server: Hapi.Server;
    readonly serviceName : Service;
    private readonly logger : Logger;
    static INSTANCE : MeetznowService;

    private constructor(serviceName : Service){

        this.serviceName = serviceName;
        this.logger = new Logger(this.serviceName, "general");
        this.server = new Hapi.Server({
            host : '0.0.0.0',
            port : process.env.PORT || 3000
        });

        this.server.route({
            method: 'GET',
            path: '/' + this.serviceName,
            handler: (request, h) => {
                return 'Connection possible!';
            }
        });

        this.server.route([{
            method: 'GET',
            path: "/" + this.serviceName + "/health",
            handler: (request, h) => {
                return "Thx, I'm fine!";
            }
        },{
            method: 'GET',
            path: "/health",
            handler: (request, h) => {
                return "Thx, I'm fine!";
            }
        }]);

        this.server.route({
            method: 'GET',
            path: '/{path*}',
            handler: async (request, h) => {
                return h.response({message : "Can't find path " + request.path + " !"}).code(200);
            }
        });

        MeetznowService.INSTANCE = this;
    }

    /**
     * starts the Server
     * @param {Service} service
     * @returns {Promise<MeetznowService>}
     */
    //Singleton
    static async start(service : Service) : Promise<MeetznowService>{
        if(MeetznowService.INSTANCE) return MeetznowService.INSTANCE;
        try {
            MeetznowService.INSTANCE = new MeetznowService(service);
            await MeetznowService.INSTANCE.server.start();
            console.log("~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~");
            console.log(`Server running at: ${MeetznowService.INSTANCE.server.info.uri}`);
            console.log("Service: " + MeetznowService.INSTANCE.serviceName);
            console.log("~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~\n");
        } catch (e) {
            console.log(e);
        }
        return MeetznowService.INSTANCE;
    }

    getLogger(namespace? : string){
        if(!namespace) return this.logger;
        return new Logger(this.serviceName, namespace)
    }

    /**
     * adds a Handler an checks for valid json form
     * @param {RequestHandler} handler
     * @returns {MeetznowService}
     */
    addHandler <RequestPayload extends BaseRequestPayload, ResponsePayload extends BaseResponsePayload, RequestHandler extends Handler<RequestPayload, ResponsePayload>>(handler : RequestHandler) : MeetznowService{
        const handle = async function (request) {
            try{
                if(typeof request.payload === "string")
                    return await handler.handle(JSON.parse(request.payload) as Request<RequestPayload>, MeetznowService.INSTANCE.getLogger());
                else if(typeof request.payload === "object")
                    return await handler.handle(request.payload as Request<RequestPayload>, MeetznowService.INSTANCE.getLogger());
                else throw Error("Request is of type " + typeof  request.payload + " but we require json/object!")
            }catch (e) {
                MeetznowService.INSTANCE.getLogger().error((request.payload as Request<RequestPayload>).toString(), e);
                return e;
            }
        };
        this.server.route([{
            method: 'POST',
            path: '/' + this.serviceName + '/' +  handler.getHandlerName(),
            handler: handle,
            options : {
                cors : true
            }},{
            method: 'POST',
            path: '/' +  handler.getHandlerName(),
            handler: handle,
            options : {
                cors : true
            }}]);
        console.log("Added handler with path: /" + handler.getHandlerName());
        return this;
    }
}