syntax = "proto3";

option csharp_namespace = "BreakfastProvider.Api.Grpc";

package breakfast;

// Breakfast Provider's gRPC API: recipe summaries and order status for kitchen systems.
service BreakfastGrpc {
  // Summarises a recipe type. Pancakes and Waffles return fixed sample figures;
  // any other recipe type returns zero batches and no ingredients.
  rpc GetRecipeSummary (RecipeSummaryRequest) returns (RecipeSummaryReply);

  // Returns an order's current status. NOT_FOUND when no order has the id.
  rpc GetOrderStatus (OrderStatusRequest) returns (OrderStatusReply);

  // Streams an order's status: today one message, the current status, then the stream completes.
  // NOT_FOUND when no order has the id.
  rpc StreamOrderUpdates (OrderStatusRequest) returns (stream OrderStatusReply);
}

// Which recipe type to summarise.
message RecipeSummaryRequest {
  // The recipe type, e.g. "Pancakes" or "Waffles".
  string recipe_type = 1;
}

// A recipe type's summary.
message RecipeSummaryReply {
  // The recipe type that was asked for.
  string recipe_type = 1;
  // How many batches have been prepared.
  int32 total_batches = 2;
  // The ingredients the recipe is usually made with.
  repeated string common_ingredients = 3;
  // When the summary was produced, ISO 8601 round-trip format.
  string last_prepared_at = 4;
}

// Which order to look up.
message OrderStatusRequest {
  // The order's id, as returned by POST /orders.
  string order_id = 1;
}

// An order's current status.
message OrderStatusReply {
  // The order's id.
  string order_id = 1;
  // Created, Preparing, Ready, Completed or Cancelled.
  string status = 2;
  // The customer the order is for.
  string customer_name = 3;
  // How many items the order has.
  int32 item_count = 4;
  // When the order was created, ISO 8601 round-trip format.
  string created_at = 5;
}