import xhrMock from 'xhr-mock';
import qs from 'qs';

import { cleanObject } from '../utils/cleanObject';

type MockResponseCb = (request: { data?: any; method: string; params?: any; status: string; }) => any;

type Mock = {
    url: string;
    method: string;
    status: number;
    response: any | MockResponseCb;
}

export class MockXHR {

    spy = jest.fn();

    mocks: Mock[] = [];

    constructor(mocks?: Mock[]) {

        xhrMock.setup();

        this.mocks = mocks || [];

        this.mocks.forEach((mock) => {
            this.add(mock);
        });
    }

    add(mock: Mock) {

        const url = new RegExp(
            mock.url
                .replace('?', '\\?')
        );

        xhrMock[mock.method.toLowerCase()](url, async (req, res) => {

            const params = req.url().query;
            const url = req.url().path;

            const request = cleanObject({
                url,
                method: req.method(),
                data: JSON.parse(req.body() || '{}'),
                params: qs.parse(
                    qs.stringify({
                            ...params,
                            ...typeof params.request === 'string' ? {
                                request: JSON.parse(params.request)
                            } : {}
                        },
                        {arrayFormat: 'repeat'}
                    )
                )
            });

            this.spy(request);

            return res.status(mock.status)
                .body(
                    JSON.stringify(
                        typeof mock.response === 'function' ?
                            mock.response(request) :
                            mock.response
                    )
                );
        });
    }

    destroy() {

        xhrMock.teardown();

        this.mocks = [];
    }

    reset() {

        this.mocks = [];

        this.spy.mockClear();

        xhrMock.reset();
    }
}