nullcart/backend/src/modules/storefrontCheckout/controllers/StorefrontCheckoutController.ts

import { Controller, Get, HttpStatus, Post, Req, Res, UseFilters, Body, BadRequestException } from '@nestjs/common';
import { Throttle } from '@nestjs/throttler';
import { ConfigService } from '@nestjs/config';
import type { Request, Response } from 'express';
import type { Config } from '../../../types/Config';
import { throttleProfiles } from '../../../config/throttleProfiles';
import { deriveCheckoutSessionState } from '../../../utils/checkout/deriveCheckoutSessionState';
import { OrderService } from '../../order/services/OrderService';
import { StorefrontExceptionFilter } from '../../storefrontCore/filters/StorefrontExceptionFilter';
import { StorefrontCartCookieService } from '../../storefrontCore/services/StorefrontCartCookieService';
import { StorefrontCheckoutSessionCookieService } from '../../storefrontCore/services/StorefrontCheckoutSessionCookieService';
import { StorefrontDiscountCookieService } from '../../storefrontCore/services/StorefrontDiscountCookieService';
import { StorefrontFeedbackCookieService } from '../../storefrontCore/services/StorefrontFeedbackCookieService';
import { StorefrontCaptchaCookieService } from '../../storefrontCore/services/StorefrontCaptchaCookieService';
import { StorefrontCaptchaService } from '../../storefrontCore/services/StorefrontCaptchaService';
import { StorefrontOrderAuthCookieService } from '../../storefrontCore/services/StorefrontOrderAuthCookieService';
import { StorefrontShopViewService } from '../../storefrontCore/services/StorefrontShopViewService';
import { StorefrontCartService } from '../../storefrontCart/services/StorefrontCartService';
import { CheckoutSessionService } from '../services/CheckoutSessionService';
import { PayCheckoutDto } from '../dto/PayCheckoutDto';
import { StorefrontCheckoutViewService } from '../services/StorefrontCheckoutViewService';

@Controller()
@UseFilters(StorefrontExceptionFilter)
export class StorefrontCheckoutController {
    constructor(
        private readonly cartService: StorefrontCartService,
        private readonly checkoutSessionService: CheckoutSessionService,
        private readonly checkoutViewService: StorefrontCheckoutViewService,
        private readonly shopViewService: StorefrontShopViewService,
        private readonly cartCookieService: StorefrontCartCookieService,
        private readonly discountCookieService: StorefrontDiscountCookieService,
        private readonly checkoutSessionCookieService: StorefrontCheckoutSessionCookieService,
        private readonly feedbackCookieService: StorefrontFeedbackCookieService,
        private readonly orderAuthCookieService: StorefrontOrderAuthCookieService,
        private readonly orderService: OrderService,
        private readonly configService: ConfigService,
        private readonly captchaService: StorefrontCaptchaService,
        private readonly captchaCookieService: StorefrontCaptchaCookieService
    ) {}

    @Post('shop/checkout/pay')
    @Throttle(throttleProfiles.checkoutPay)
    async pay(@Req() req: Request, @Res() res: Response, @Body() { captcha, paymentMethod }: PayCheckoutDto): Promise<void> {
        const sessionId = this.checkoutSessionCookieService.getSessionId(req, res);

        if (sessionId) {
            res.redirect(HttpStatus.FOUND, '/shop/checkout');

            return;
        }

        const encryptedAnswer = this.captchaCookieService.getAnswer(req, res, { consume: true });

        const isCaptchaValid = this.captchaService.verify(captcha, encryptedAnswer);

        if (!isCaptchaValid) {
            throw new BadRequestException('Incorrect captcha. Try again.');
        }

        const cart = this.cartCookieService.getCart(req, res);

        const discountCodes = this.discountCookieService.getDiscountCodes(req, res);

        const summary = await this.cartService.getCartSummary(cart, discountCodes);

        const session = await this.checkoutSessionService.createFromCartSummary(summary, paymentMethod);

        this.checkoutSessionCookieService.setSessionId(req, res, session.id);

        res.redirect(HttpStatus.FOUND, '/shop/checkout');
    }

    @Get('shop/checkout')
    async checkoutPage(@Req() req: Request, @Res() res: Response) {
        const sessionId = this.checkoutSessionCookieService.getSessionId(req, res);

        if (!sessionId) {
            res.redirect(HttpStatus.FOUND, '/shop/cart');

            return;
        }

        const session = await this.checkoutSessionService.findById(sessionId);

        if (!session) {
            this.checkoutSessionCookieService.clearSession(req, res);

            this.feedbackCookieService.setFeedback(req, res, {
                type: 'error',
                text: 'Checkout session no longer available.'
            });

            res.redirect(HttpStatus.FOUND, '/shop/cart');

            return;
        }

        const orderId = await this.orderService.findIdByCheckoutSessionId(sessionId);

        if (orderId) {
            this.checkoutSessionCookieService.clearSession(req, res);
            this.cartCookieService.clearCart(req, res);
            this.discountCookieService.clearDiscount(req, res);

            this.orderAuthCookieService.grantAccess(req, res, orderId);

            this.feedbackCookieService.setFeedback(req, res, {
                type: 'success',
                text: 'Order placed successfully.'
            });

            res.redirect(HttpStatus.FOUND, `/shop/order/${orderId}`);

            return;
        }

        const sessionState = deriveCheckoutSessionState(session);

        if (sessionState.isPastDue) {
            this.checkoutSessionCookieService.clearSession(req, res);

            this.feedbackCookieService.setFeedback(req, res, {
                type: 'error',
                text: 'Checkout session expired.'
            });

            res.redirect(HttpStatus.FOUND, '/shop/cart');

            return;
        }

        if (sessionState.isCancelled) {
            this.checkoutSessionCookieService.clearSession(req, res);

            this.feedbackCookieService.setFeedback(req, res, {
                type: 'success',
                text: 'Checkout cancelled.'
            });

            res.redirect(HttpStatus.FOUND, '/shop/cart');

            return;
        }

        const [shopLocals, checkoutView] = await Promise.all([
            this.shopViewService.buildShopRenderLocals(req, res, {
                title: 'Checkout',
                metaDescription: 'Complete your purchase at {shopName}.'
            }),
            this.checkoutViewService.toCheckoutView(session)
        ]);

        const { checkoutStatusRefreshSec } = this.configService.get('order') as Config['order'];

        return res.render('checkout', {
            checkout: checkoutView,
            refreshSec: checkoutStatusRefreshSec,
            ...shopLocals
        });
    }

    @Post('shop/checkout/cancel')
    async cancelCheckout(@Req() req: Request, @Res() res: Response): Promise<void> {
        const sessionId = this.checkoutSessionCookieService.getSessionId(req, res);

        if (sessionId) {
            await this.checkoutSessionService.cancelSession(sessionId);
        }

        this.checkoutSessionCookieService.clearSession(req, res);

        this.feedbackCookieService.setFeedback(req, res, {
            type: 'success',
            text: 'Checkout cancelled.'
        });

        res.redirect(HttpStatus.FOUND, '/shop/cart');
    }
}