Paypal+API.swift

//
// Copyright 2022 Signal Messenger, LLC
// SPDX-License-Identifier: AGPL-3.0-only
//

import Foundation

// MARK: - Boost

public extension Paypal {
    /// Create a payment and get a PayPal approval URL to present to the user.
    static func createBoost(
        amount: FiatMoney,
        level: OneTimeBadgeLevel,
    ) async throws -> (URL, String) {
        let createBoostRequest = OWSRequestFactory.boostPaypalCreatePayment(
            integerMoneyValue: DonationUtilities.integralAmount(for: amount),
            inCurrencyCode: amount.currencyCode,
            level: level.rawValue,
            returnUrl: Self.webAuthReturnUrl,
            cancelUrl: Self.webAuthCancelUrl,
        )

        let response = try await SSKEnvironment.shared.networkManagerRef
            .asyncRequest(createBoostRequest, retryPolicy: .hopefullyRecoverable)

        guard let parser = response.responseBodyParamParser else {
            throw OWSAssertionError("[Donations] Failed to decode JSON response")
        }

        let approvalUrlString: String = try parser.required(key: "approvalUrl")
        let paymentId: String = try parser.required(key: "paymentId")

        guard let approvalUrl = URL(string: approvalUrlString) else {
            throw OWSAssertionError("[Donations] Approval URL was not a valid URL!")
        }

        return (approvalUrl, paymentId)
    }

    /// Confirms a payment after a successful authentication via PayPal's web
    /// UI. Returns a payment ID that can be used to get receipt credentials.
    static func confirmOneTimePayment(
        amount: FiatMoney,
        level: OneTimeBadgeLevel,
        paymentId: String,
        approvalParams: OneTimePaymentWebAuthApprovalParams,
    ) async throws -> String {
        let confirmOneTimePaymentRequest = OWSRequestFactory.oneTimePaypalConfirmPayment(
            integerMoneyValue: DonationUtilities.integralAmount(for: amount),
            inCurrencyCode: amount.currencyCode,
            level: level.rawValue,
            payerId: approvalParams.payerId,
            paymentId: paymentId,
            paymentToken: approvalParams.paymentToken,
        )

        let response = try await SSKEnvironment.shared.networkManagerRef
            .asyncRequest(confirmOneTimePaymentRequest, retryPolicy: .hopefullyRecoverable)

        guard let parser = response.responseBodyParamParser else {
            throw OWSAssertionError("[Donations] Failed to decode JSON response")
        }

        return try parser.required(key: "paymentId")
    }
}

// MARK: - Subscription

public extension Paypal {
    struct SubscriptionAuthorizationParams {
        /// A URL to present to the user to authorize the subscription.
        public let approvalUrl: URL

        /// An opaque ID identifying the payment method, for API calls after
        /// subscription authorization.
        public let paymentMethodId: String
    }

    /// Create a payment method entry with the Signal service for a subscription
    /// processed by PayPal.
    ///
    /// - Returns
    /// PayPal params used to authorize payment for the new subscription.
    static func createSignalPaymentMethodForSubscription(
        subscriberId: Data,
    ) async throws -> SubscriptionAuthorizationParams {
        let request = OWSRequestFactory.subscriptionCreatePaypalPaymentMethodRequest(
            subscriberID: subscriberId,
            returnURL: Self.webAuthReturnUrl,
            cancelURL: Self.webAuthCancelUrl,
        )

        let response = try await SSKEnvironment.shared.networkManagerRef
            .asyncRequest(request, retryPolicy: .hopefullyRecoverable)

        guard let parser = response.responseBodyParamParser else {
            throw OWSAssertionError("[Donations] Missing or invalid response.")
        }

        guard let approvalUrl = URL(string: try parser.required(key: "approvalUrl")) else {
            throw OWSAssertionError("[Donations] Approval URL string was not valid URL!")
        }

        let paymentMethodId: String = try parser.required(key: "token")

        return SubscriptionAuthorizationParams(
            approvalUrl: approvalUrl,
            paymentMethodId: paymentMethodId,
        )
    }
}