/*
 * SPDX-FileCopyrightText: 2023 Contributors to the Eclipse Foundation
 *
 * See the NOTICE file(s) distributed with this work for additional
 * information regarding copyright ownership.
 * 
 * This program and the accompanying materials are made available under
 * the terms of the Apache License Version 2.0 which is available at
 * https://www.apache.org/licenses/LICENSE-2.0
 *
 * SPDX-FileType: SOURCE
 * SPDX-License-Identifier: Apache-2.0
 */
syntax = "proto3";

package uprotocol.v1;

import "uprotocol/v1/uri.proto";
import "uprotocol/v1/uuid.proto";
import "uprotocol/v1/ucode.proto";
import "uprotocol/uoptions.proto";

option java_package = "org.eclipse.uprotocol.v1";
option java_outer_classname = "UAttributesProto";
option java_multiple_files = true;

// Metadata describing a particular message's purpose, content and processing requirements.
// Each type of message is described by a set of mandatory and optional attributes.
message UAttributes {
    // A unique message identifier.
    UUID id = 1;

    // This message's type which also indicates its purpose and determines contraints on the other properties.
    UMessageType type = 2;

    // The origin (address) of this message.
    UUri source = 3;

    // The destination (address) of this message.
    UUri sink = 4;

    // The QoS level that this message should be processed/delivered with.
    UPriority priority = 5;

    // The amount of time (in milliseconds) after which this message MUST NOT be delivered/processed anymore.
    optional uint32 ttl = 6;

    // The service consumer's permission level.
    optional uint32 permission_level = 7;

    // A UCode indicating an error that has occurred
    // during the delivery of either an RPC Request or Response message.
    optional UCode commstatus = 8;

    // The identifier that a service consumer can use to correlate an RPC Repsonse message with its RPC Request.
    UUID reqid = 9;

    // The service consumer's access token.
    optional string token = 10;

    // A tracing identifier to use for correlating messages across the system.
    // Intended to be compatible with https://github.com/cloudevents/spec/blob/main/cloudevents/extensions/distributed-tracing.md
    optional string traceparent = 11;

    // The format for the data stored in the UMessage.
    UPayloadFormat payload_format = 12;
}


// uProtocol defines different types of messages.
// Using the message type, validation can be performed to ensure transport
// validity of the data in the {@link UAttributes}.
enum UMessageType {
    // Unspecified message type
    UMESSAGE_TYPE_UNSPECIFIED = 0;

    // Publish
    // A message that is used to notify all interested consumers of an event that has occurred.
    UMESSAGE_TYPE_PUBLISH = 1 [(uprotocol.ce_name) = "pub.v1"];

    // RPC Request
    // A message that is used by a service consumer to invoke one of a service provider's methods with some input data, expecting the service
    // provider to reply with a response message.
    UMESSAGE_TYPE_REQUEST = 2 [(uprotocol.ce_name) = "req.v1"];

    // RPC Response
    // A message that is used by a service provider to send the outcome of processing a request message
    // from a servcice consumer.
    UMESSAGE_TYPE_RESPONSE = 3 [(uprotocol.ce_name) = "res.v1"];

    // Notification
    // A message that is used to inform a specific consumer about an event that has occurred.
    UMESSAGE_TYPE_NOTIFICATION = 4 [(uprotocol.ce_name) = "not.v1"];
}


// uProtocol Priority as defined in
// https://github.com/eclipse-uprotocol/up-spec/blob/main/basics/qos.adoc[uProtocol Prioritization]
enum UPriority {
    // Unspecified priority
    UPRIORITY_UNSPECIFIED = 0;

    // Low Priority. No bandwidth assurance such as File Transfer.
    UPRIORITY_CS0 = 1 [(uprotocol.ce_name) = "CS0"];

    // Standard, undifferentiated application such as General (unclassified).
    UPRIORITY_CS1 = 2 [(uprotocol.ce_name) = "CS1"];

    // Operations, Administration, and Management such as Streamer messages (sub, connect, etc…)
    UPRIORITY_CS2 = 3 [(uprotocol.ce_name) = "CS2"];

    // Multimedia streaming such as Video Streaming
    UPRIORITY_CS3 = 4 [(uprotocol.ce_name) = "CS3"];

    // Real-time interactive such as High priority (rpc events)
    UPRIORITY_CS4 = 5 [(uprotocol.ce_name) = "CS4"];

    // Signaling such as Important
    UPRIORITY_CS5 = 6 [(uprotocol.ce_name) = "CS5"];

    // Network control such as Safety Critical
    UPRIORITY_CS6 = 7 [(uprotocol.ce_name) = "CS6"];
}

// The format for the data stored in the UMessage.
enum UPayloadFormat {
    // Payload format was not is not set,
    // per specification, assumption is UPAYLOAD_FORMAT_PROTOBUF_WRAPPED_IN_ANY
    UPAYLOAD_FORMAT_UNSPECIFIED = 0;

    // Payload is an Any protobuf message that contains the packed payload
    UPAYLOAD_FORMAT_PROTOBUF_WRAPPED_IN_ANY = 1 [ (uprotocol.mime_type) = "application/x-protobuf" ];

    // Protobuf serialization format
    UPAYLOAD_FORMAT_PROTOBUF = 2 [ (uprotocol.mime_type) = "application/protobuf" ];

    // JSON serialization format
    UPAYLOAD_FORMAT_JSON = 3 [ (uprotocol.mime_type) = "application/json" ];

    // Basic SOME/IP serialization format
    UPAYLOAD_FORMAT_SOMEIP = 4 [ (uprotocol.mime_type) = "application/x-someip" ];

    // SOME/IP TLV format
    UPAYLOAD_FORMAT_SOMEIP_TLV = 5 [ (uprotocol.mime_type) = "application/x-someip_tlv" ];

    // RAW (binary) format
    UPAYLOAD_FORMAT_RAW = 6 [ (uprotocol.mime_type) = "application/octet-stream" ];

    // Text format
    UPAYLOAD_FORMAT_TEXT = 7 [ (uprotocol.mime_type) = "text/plain" ];

    // Shared memory format
    UPAYLOAD_FORMAT_SHM = 8 [ (uprotocol.mime_type) = "application/x-shm" ];
}