WIP get billing preview when holiday stop api is called

handlers/holiday-stop-api/src/main/scala/com/gu/holiday_stops/Handler.scala

@@ -103,6 +103,8 @@ object Handler extends Logging {
           idGenerator,
           FulfilmentDatesFetcher(fetchString, Stage()),
           PreviewPublications.preview,
+          getBillingPreviewFromZuora(config, backend),
+          LocalDate.now,
         )(
           request,
           sfClient.setupRequest(withAlternateAccessTokenIfPresentInHeaderList(request.headers)),
@@ -118,6 +120,8 @@ object Handler extends Logging {
       idGenerator: => String,
       fulfilmentDatesFetcher: FulfilmentDatesFetcher,
       previewPublications: (String, String, String) => Either[ApiFailure, PreviewPublicationsResponse] = null, // FIXME
+      getBillingPreview: GetBillingPreview,
+      today: LocalDate,
   ) = {
     (for {
       httpMethod <- validateMethod(request.httpMethod)
@@ -131,6 +135,8 @@ object Handler extends Logging {
       idGenerator,
       fulfilmentDatesFetcher,
       previewPublications,
+      getBillingPreview,
+      today,
     )).fold(
       { errorMessage: String =>
         badrequest(errorMessage) _
@@ -162,6 +168,8 @@ object Handler extends Logging {
       idGenerator: => String,
       fulfilmentDatesFetcher: FulfilmentDatesFetcher,
       previewPublications: (String, String, String) => Either[ApiFailure, PreviewPublicationsResponse] = null, // FIXME
+      getBillingPreview: GetBillingPreview,
+      today: LocalDate,
   ) = {
     path match {
       case "potential" :: _ :: Nil =>
@@ -171,12 +179,12 @@ object Handler extends Logging {
         }
       case "hsr" :: Nil =>
         httpMethod match {
-          case "POST" => stepsToCreate(getAccessToken, getSubscription, getAccount) _
+          case "POST" => stepsToCreate(getAccessToken, getSubscription, getAccount, getBillingPreview, today) _
           case _ => unsupported _
         }
       case "bulk-hsr" :: Nil =>
         httpMethod match {
-          case "POST" => stepsToBulkCreate(getAccessToken, getSubscription, getAccount) _
+          case "POST" => stepsToBulkCreate(getAccessToken, getSubscription, getAccount, getBillingPreview, today) _
           case _ => unsupported _
         }
       case "hsr" :: _ :: Nil =>
@@ -371,31 +379,41 @@ object Handler extends Logging {
       getAccessToken: () => Either[ApiFailure, AccessToken],
       getSubscription: (AccessToken, SubscriptionName) => Either[ApiFailure, Subscription],
       getAccount: (AccessToken, String) => Either[ApiFailure, ZuoraAccount],
+      getBillingPreview: GetBillingPreview,
+      today: LocalDate,
   )(req: ApiGatewayRequest, sfClient: SfClient): ApiResponse =
     stepsToCreate(
       getAccessToken,
       getSubscription,
       getAccount,
       req.bodyAsCaseClass[HolidayStopRequestPartial](),
+      getBillingPreview,
+      today,
     )(req, sfClient)
 
   def stepsToBulkCreate(
       getAccessToken: () => Either[ApiFailure, AccessToken],
       getSubscription: (AccessToken, SubscriptionName) => Either[ApiFailure, Subscription],
       getAccount: (AccessToken, String) => Either[ApiFailure, ZuoraAccount],
+      getBillingPreview: GetBillingPreview,
+      today: LocalDate,
   )(req: ApiGatewayRequest, sfClient: SfClient): ApiResponse =
     stepsToCreate(
       getAccessToken,
       getSubscription,
       getAccount,
       req.bodyAsCaseClass[BulkHolidayStopRequestPartial](),
+      getBillingPreview,
+      today,
     )(req, sfClient)
 
   private def stepsToCreate(
       getAccessToken: () => Either[ApiFailure, AccessToken],
       getSubscription: (AccessToken, SubscriptionName) => Either[ApiFailure, Subscription],
       getAccount: (AccessToken, String) => Either[ApiFailure, ZuoraAccount],
       requestBodyOp: ApiGatewayOp[HolidayStopRequestPartialTrait],
+      getBillingPreview: GetBillingPreview,
+      today: LocalDate,
   )(req: ApiGatewayRequest, sfClient: SfClient): ApiResponse = {
 
     val verifyContactOwnsSubOp =
@@ -416,6 +434,10 @@ object Handler extends Logging {
         .toApiGatewayOp(s"get subscription ${requestBody.subscriptionName}")
       account <- getAccount(accessToken, subscription.accountNumber)
         .toApiGatewayOp(s"get account ${subscription.accountNumber}")
+      billingPreview <- getBillingPreview
+        .getBillingPreview(accessToken, subscription.accountNumber, today.plusMonths(13))
+        .toApiGatewayOp(s"get billing preview for account ${subscription.accountNumber}")
+      _ = logger.info("billingPreview: " + billingPreview)
       issuesData <- SubscriptionData(subscription, account)
         .map(_.issueDataForPeriod(requestBody.startDate, requestBody.endDate))
         .toApiGatewayOp(s"calculating publication dates")
@@ -576,6 +598,12 @@ object Handler extends Logging {
       accountKey: String,
   ): Either[ApiFailure, ZuoraAccount] = Zuora.accountGetResponse(config.zuoraConfig, accessToken, backend)(accountKey)
 
+  def getBillingPreviewFromZuora(
+      config: Config,
+      backend: SttpBackend[Identity, Any],
+  ): GetBillingPreview =
+    GetBillingPreviewLive.billingPreviewGetResponse(config.zuoraConfig, backend)
+
   def getAccessTokenFromZuora(
       config: Config,
       backend: SttpBackend[Identity, Any],

handlers/holiday-stop-api/src/test/scala/com/gu/holiday_stops/GetBillingPreviewEffectsTest.scala

@@ -0,0 +1,43 @@
+package com.gu.holiday_stops
+
+import cats.Id
+import com.gu.holiday_stops.Handler.{getAccessTokenFromZuora, getBillingPreviewFromZuora}
+import com.gu.test.EffectsTest
+import org.scalatest.flatspec.AnyFlatSpec
+import org.scalatest.matchers.should.Matchers
+import sttp.client3.HttpURLConnectionBackend
+import sttp.client3.logging.{LogLevel, Logger, LoggingBackend}
+
+import java.time.LocalDate
+
+class GetBillingPreviewEffectsTest extends AnyFlatSpec with Matchers {
+
+  lazy val config = {
+    zio.Runtime.default.unsafeRun {
+      Configuration.config.provideLayer(ConfigurationLive.impl)
+    }
+  }
+
+  lazy val backend = LoggingBackend(
+    HttpURLConnectionBackend(),
+    new Logger[Id] {
+      override def apply(level: LogLevel, message: => String): Id[Unit] = info("LOG: " + message)
+
+      override def apply(level: LogLevel, message: => String, t: Throwable): Id[Unit] =
+        info("LOG: " + message + t.toString)
+    },
+    logResponseBody = true,
+  )
+
+  "get billing preview" should "fetch a test subscription's preview" taggedAs EffectsTest ignore {
+
+    val ACCOUNT_TO_USE = "A00211577"
+
+    val op = getBillingPreviewFromZuora(config, backend)
+    val accessToken = getAccessTokenFromZuora(config, backend).toOption.get
+
+    val preview = op.getBillingPreview(accessToken, ACCOUNT_TO_USE, LocalDate.now.plusMonths(13))
+    info("preview is: " + preview)
+    preview.toOption.get.length shouldBe 26
+  }
+}

lib/zuora-core/src/main/scala/com/gu/zuora/subscription/GetBillingPreview.scala

@@ -0,0 +1,62 @@
+package com.gu.zuora.subscription
+
+import com.gu.zuora.{AccessToken, ZuoraConfig}
+import io.circe.generic.semiauto._
+import io.circe.{Decoder, Encoder, HCursor}
+import sttp.client3._
+import sttp.client3.circe._
+
+import java.time.LocalDate
+
+object GetBillingPreview {
+
+  case class InvoiceItem(
+      chargeDate: LocalDate,
+      chargeId: String,
+  )
+  implicit val decode: Decoder[InvoiceItem] = (c: HCursor) =>
+    for {
+      chargeDate <- c.downField("chargeDate").as[String].map(_.takeWhile(_ != ' ')).map(LocalDate.parse)
+      chargeId <- c.downField("chargeId").as[String]
+    } yield InvoiceItem(chargeDate, chargeId)
+
+  case class BillingPreview(
+      invoiceItems: List[InvoiceItem],
+  )
+  implicit val decode2: Decoder[BillingPreview] = deriveDecoder
+  implicit val encode: Encoder[BillingPreviewRequest] = deriveEncoder
+  case class BillingPreviewRequest(
+      accountNumber: String,
+      targetDate: LocalDate,
+      assumeRenewal: String = "Autorenew",
+  )
+}
+trait GetBillingPreview {
+  import GetBillingPreview._
+  def getBillingPreview(
+      accessToken: AccessToken,
+      accountNumber: String,
+      targetDate: LocalDate,
+  ): Either[ApiFailure, List[InvoiceItem]]
+}
+
+object GetBillingPreviewLive {
+
+  def billingPreviewGetResponse(
+      config: ZuoraConfig,
+      backend: SttpBackend[Identity, Any],
+  ): GetBillingPreview =
+    (accessToken: AccessToken, accountNumber: String, targetDate: LocalDate) => {
+      val request = GetBillingPreview.BillingPreviewRequest(accountNumber, targetDate)
+      basicRequest
+        .post(uri"${config.baseUrl}/operations/billing-preview")
+        .body(request)
+        .header("Authorization", s"Bearer ${accessToken.access_token}")
+        .response(asJson[GetBillingPreview.BillingPreview])
+        .mapResponse(_.left.map(e => ZuoraApiFailure(e.getMessage)))
+        .send(backend)
+        .body
+        .map(_.invoiceItems)
+    }
+
+}