// Copyright Epic Games, Inc. All Rights Reserved.

#pragma once

#include <protozero/types.hpp>

//////////////////////////////////////////////////////////////////////////
//
//  OTEL .proto definitions, for reference
//

#if 0

// clang-format off

////////////////////////////////////////////////////////////////////////
// resource/v1/resource.proto
//

// Resource information.
message Resource {
  // Set of attributes that describe the resource.
  // Attribute keys MUST be unique (it is not allowed to have more than one
  // attribute with the same key).
  //
  // The attribute values SHOULD NOT contain empty values.
  // The attribute values SHOULD NOT contain bytes values.
  // The attribute values SHOULD NOT contain array values different than array of string values, bool values, int values,
  // double values.
  // The attribute values SHOULD NOT contain kvlist values.
  // The behavior of software that receives attributes containing such values can be unpredictable.
  // These restrictions can change in a minor release.
  // The restrictions take origin from the OpenTelemetry specification:
  // https://github.com/open-telemetry/opentelemetry-specification/blob/v1.47.0/specification/common/README.md#attribute.
  repeated opentelemetry.proto.common.v1.KeyValue attributes = 1;

  // The number of dropped attributes. If the value is 0, then
  // no attributes were dropped.
  uint32 dropped_attributes_count = 2;

  // Set of entities that participate in this Resource.
  //
  // Note: keys in the references MUST exist in attributes of this message.
  //
  // Status: [Development]
  repeated opentelemetry.proto.common.v1.EntityRef entity_refs = 3;
}

/////////////////////////////////////////////////////////////////////////
// common/v1/commmon.proto
//

// Represents any type of attribute value. AnyValue may contain a
// primitive value such as a string or integer or it may contain an arbitrary nested
// object containing arrays, key-value lists and primitives.
message AnyValue {
  // The value is one of the listed fields. It is valid for all values to be unspecified
  // in which case this AnyValue is considered to be "empty".
  oneof value {
    string string_value = 1;
    bool bool_value = 2;
    int64 int_value = 3;
    double double_value = 4;
    ArrayValue array_value = 5;
    KeyValueList kvlist_value = 6;
    bytes bytes_value = 7;
  }
}

// ArrayValue is a list of AnyValue messages. We need ArrayValue as a message
// since oneof in AnyValue does not allow repeated fields.
message ArrayValue {
  // Array of values. The array may be empty (contain 0 elements).
  repeated AnyValue values = 1;
}

// KeyValueList is a list of KeyValue messages. We need KeyValueList as a message
// since `oneof` in AnyValue does not allow repeated fields. Everywhere else where we need
// a list of KeyValue messages (e.g. in Span) we use `repeated KeyValue` directly to
// avoid unnecessary extra wrapping (which slows down the protocol). The 2 approaches
// are semantically equivalent.
message KeyValueList {
  // A collection of key/value pairs of key-value pairs. The list may be empty (may
  // contain 0 elements).
  // The keys MUST be unique (it is not allowed to have more than one
  // value with the same key).
  repeated KeyValue values = 1;
}

// Represents a key-value pair that is used to store Span attributes, Link
// attributes, etc.
message KeyValue {
  // The key name of the pair.
  string key = 1;

  // The value of the pair.
  AnyValue value = 2;
}

// InstrumentationScope is a message representing the instrumentation scope information
// such as the fully qualified name and version. 
message InstrumentationScope {
  // A name denoting the Instrumentation scope.
  // An empty instrumentation scope name means the name is unknown.
  string name = 1;

  // Defines the version of the instrumentation scope.
  // An empty instrumentation scope version means the version is unknown.
  string version = 2;

  // Additional attributes that describe the scope. [Optional].
  // Attribute keys MUST be unique (it is not allowed to have more than one
  // attribute with the same key).
  repeated KeyValue attributes = 3;

  // The number of attributes that were discarded. Attributes
  // can be discarded because their keys are too long or because there are too many
  // attributes. If this value is 0, then no attributes were dropped.
  uint32 dropped_attributes_count = 4;
}

// clang-format on
#endif

//////////////////////////////////////////////////////////////////////////

namespace zen::otel {

enum class KeyValueList : protozero::pbf_tag_type
{
	repeated_KeyValue_values = 1
};

enum class KeyValue : protozero::pbf_tag_type
{
	string_key	   = 1,
	AnyValue_value = 2
};

enum class Resource : protozero::pbf_tag_type
{
	repeated_KeyValue_attributes	= 1,
	uint32_dropped_attributes_count = 2,
	repeated_EntityRef_entity_refs	= 3
};

enum class AnyValue : protozero::pbf_tag_type
{
	string_string_value		  = 1,
	bool_bool_value			  = 2,
	int64_int_value			  = 3,
	double_double_value		  = 4,
	ArrayValue_array_value	  = 5,
	KeyValueList_kvlist_value = 6,
	bytes_bytes_value		  = 7
};

enum class InstrumentationScope : protozero::pbf_tag_type
{
	string_name						= 1,
	string_version					= 2,
	repeated_KeyValue_attributes	= 3,
	uint32_dropped_attributes_count = 4
};

}  // namespace zen::otel