import createNewDbConnection, { StoccaTreDbConn } from "./database.ts";
import * as resources from "./resources/main.ts";
import config from "./config.ts";
import StoccaTreRequest, { HttpMethod } from "./StoccaTreRequest.ts";
import { JSONObject } from "./JSON.ts";
import StoccaTreServer from "./StoccaTreServer.ts";
import {Result, StoccaTreError} from "./Result.ts";

type StoccaTreApiBody = {
    data: JSONObject;
    error?: string;
};

function newStoccaTreApiBody(): StoccaTreApiBody {
    return {
        data: {},
    };
}

async function getJSONBody(request: Request): Promise<Result<JSONObject | null>> {
    let json;
    try {
        if (request.body) {
            json = await request.json();
        } else {
            json = null;
        }
    } catch (e: unknown) {
        return [new StoccaTreError((e as Error).message ?? "Body was invalid JSON.", 400)];
    }
    return [, json];
}

async function respondWithError(requestEvent: Deno.RequestEvent, error: StoccaTreError) {
    const body = newStoccaTreApiBody();
    await requestEvent.respondWith(
        Response.json({
            ...body,
            status: error.status,
            error: error.qualified("Error: ").message,
        }, { status: error.status }),
    );
}

async function processRequest(
    server: StoccaTreServer,
    requestEvent: Deno.RequestEvent,
) {
    const [bodyError, requestBody] = await getJSONBody(requestEvent.request);
    if (bodyError) {
        await respondWithError(requestEvent, bodyError);
        return;
    }
    const route = /^https?:\/\/[^\/]*(\/.*)$/.exec(requestEvent.request.url)?.[1] ?? "/";
    const method: HttpMethod = requestEvent.request.method as HttpMethod;
    const body: StoccaTreApiBody = newStoccaTreApiBody();
    const [error, result] = await server.handleRequest(new StoccaTreRequest(method, route, requestBody));
    if (error) {
        await respondWithError(requestEvent, error);
        return;
    }
    body.data = result;
    await requestEvent.respondWith(Response.json(body, { status: 200 }));
}


const [error, database] = await createNewDbConnection();

if (error) {
    console.log(error.qualified("Failed to create the database: ").message);
} else {
    const server = new StoccaTreServer(database);
    server.addResource({ pattern: /ingredient/ }, new resources.IngredientResource(database));
    server.addResource({ pattern: /user/ }, new resources.UserResource(database));
    const stoccaTreListener = Deno.listen({ port: config.port ?? 8080 });
    console.log(`Stocca Tre Server is running. Access it at: http://${ config.hostname }:${ config.port }/`);
    for await (const conn of stoccaTreListener) {
        const httpConn = Deno.serveHttp(conn);
        for await (const requestEvent of httpConn) {
            await processRequest(server, requestEvent);
        }
    }
}