MerchantApi.kt

/*
 * This file is part of GNU Taler
 * (C) 2020 Taler Systems S.A.
 *
 * GNU Taler is free software; you can redistribute it and/or modify it under the
 * terms of the GNU General Public License as published by the Free Software
 * Foundation; either version 3, or (at your option) any later version.
 *
 * GNU Taler is distributed in the hope that it will be useful, but WITHOUT ANY
 * WARRANTY; without even the implied warranty of MERCHANTABILITY or FITNESS FOR
 * A PARTICULAR PURPOSE.  See the GNU General Public License for more details.
 *
 * You should have received a copy of the GNU General Public License along with
 * GNU Taler; see the file COPYING.  If not, see <http://www.gnu.org/licenses/>
 */

package net.taler.merchantlib

import io.ktor.client.HttpClient
import io.ktor.client.call.body
import io.ktor.client.request.HttpRequestBuilder
import io.ktor.client.request.delete
import io.ktor.client.request.get
import io.ktor.client.request.header
import io.ktor.client.request.post
import io.ktor.client.request.parameter
import io.ktor.client.request.setBody
import io.ktor.http.ContentType.Application.Json
import io.ktor.http.HttpHeaders.Authorization
import io.ktor.http.contentType
import kotlinx.coroutines.CoroutineDispatcher
import kotlinx.coroutines.Dispatchers
import kotlinx.coroutines.withContext
import net.taler.common.getDefaultHttpClient
import net.taler.merchantlib.Response.Companion.response

class MerchantApi(
    private val httpClient: HttpClient = getDefaultHttpClient(),
    private val ioDispatcher: CoroutineDispatcher = Dispatchers.IO,
) {

    suspend fun getConfig(baseUrl: String): Response<ConfigResponse> = withContext(ioDispatcher) {
        response {
            httpClient.get("$baseUrl/config").body()
        }
    }

    suspend fun postOrder(
        merchantConfig: MerchantConfig,
        orderRequest: PostOrderRequest,
    ): Response<PostOrderResponse> = withContext(ioDispatcher) {
        response {
            httpClient.post(merchantConfig.urlFor("private/orders")) {
                auth(merchantConfig)
                contentType(Json)
                setBody(orderRequest)
            }.body()
        }
    }

    suspend fun checkOrder(
        merchantConfig: MerchantConfig,
        orderId: String,
    ): Response<CheckPaymentResponse> = withContext(ioDispatcher) {
        response {
            httpClient.get(merchantConfig.urlFor("private/orders/$orderId")) {
                auth(merchantConfig)
            }.body()
        }
    }

    suspend fun getUnits(merchantConfig: MerchantConfig): Response<MerchantUnitsResponse> = withContext(ioDispatcher) {
        response {
            httpClient.get(merchantConfig.urlFor("private/units")) {
                auth(merchantConfig)
            }.body()
        }
    }

    suspend fun deleteOrder(
        merchantConfig: MerchantConfig,
        orderId: String,
        force: Boolean = false,
    ): Response<Unit> = withContext(ioDispatcher) {
        response {
            httpClient.delete(merchantConfig.urlFor("private/orders/$orderId")) {
                auth(merchantConfig)
                if (force) parameter("force", "yes")
            }.body()
        }
    }

    /**
     * Completes an order settled entirely outside Taler, exactly as a wallet paying the
     * free order would. Only for orders with a zero amount; requires protocol v42.
     */
    suspend fun collectOrder(
        merchantConfig: MerchantConfig,
        orderId: String,
    ): Response<Unit> = withContext(ioDispatcher) {
        response {
            httpClient.post(merchantConfig.urlFor("private/orders/$orderId/collect")) {
                auth(merchantConfig)
                contentType(Json)
                setBody(CollectOrderRequest())
            }.body()
        }
    }

    suspend fun getOrderHistory(
        merchantConfig: MerchantConfig,
        limit: Int = -20,
        offset: Long? = null,
    ): Response<OrderHistory> =
        withContext(ioDispatcher) {
            response {
                httpClient.get(merchantConfig.urlFor("private/orders")) {
                    auth(merchantConfig)
                    parameter("limit", limit)
                    offset?.let { parameter("offset", it) }
                }.body()
            }
        }

    suspend fun giveRefund(
        merchantConfig: MerchantConfig,
        orderId: String,
        request: RefundRequest,
    ): Response<RefundResponse> = withContext(ioDispatcher) {
        response {
            httpClient.post(merchantConfig.urlFor("private/orders/$orderId/refund")) {
                auth(merchantConfig)
                contentType(Json)
                setBody(request)
            }.body()
        }
    }

    /** Records a refund settled outside Taler; requires protocol v42. */
    suspend fun refundExternal(
        merchantConfig: MerchantConfig,
        orderId: String,
        request: ExternalRefundRequest,
    ): Response<Unit> = withContext(ioDispatcher) {
        response {
            httpClient.post(merchantConfig.urlFor("private/orders/$orderId/refund-external")) {
                auth(merchantConfig)
                contentType(Json)
                setBody(request)
            }.body()
        }
    }

    private fun HttpRequestBuilder.auth(merchantConfig: MerchantConfig) {
        header(Authorization, "Bearer ${merchantConfig.apiKey}")
    }
}