// Copyright 2020 The OpenTelemetry Authors
//
// Licensed under the Apache License, Version 2.0 (the "License");
// you may not use this file except in compliance with the License.
// You may obtain a copy of the License at
//
//      http://www.apache.org/licenses/LICENSE-2.0
//
// Unless required by applicable law or agreed to in writing, software
// distributed under the License is distributed on an "AS IS" BASIS,
// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
// See the License for the specific language governing permissions and
// limitations under the License.

package kafkaexporter

import (
	"time"

	"go.opentelemetry.io/collector/config/configmodels"
)

// Config defines configuration for Kafka exporter.
type Config struct {
	configmodels.ExporterSettings `mapstructure:",squash"`
	// The list of kafka brokers (default localhost:9092)
	Brokers []string `mapstructure:"brokers"`
	// Kafka protocol version
	ProtocolVersion string `mapstructure:"protocol_version"`
	// The name of the kafka topic to export to (default "otlp_spans")
	Topic string `mapstructure:"topic"`

	// Metadata is the namespace for metadata management properties used by the
	// Client, and shared by the Producer/Consumer.
	Metadata Metadata `mapstructure:"metadata"`

	// TODO authentication
	// TODO batch settings
}

// Metadata defines configuration for retrieving metadata from the broker.
type Metadata struct {
	// Whether to maintain a full set of metadata for all topics, or just
	// the minimal set that has been necessary so far. The full set is simpler
	// and usually more convenient, but can take up a substantial amount of
	// memory if you have many topics and partitions. Defaults to true.
	Full bool `mapstructure:"full"`

	// Retry configuration for metadata.
	// This configuration is useful to avoid race conditions when broker
	// is starting at the same time as collector.
	Retry MetadataRetry `mapstructure:"retry"`
}

// MetadataRetry defines retry configuration for Metadata.
type MetadataRetry struct {
	// The total number of times to retry a metadata request when the
	// cluster is in the middle of a leader election or at startup (default 3).
	Max int `mapstructure:"max"`
	// How long to wait for leader election to occur before retrying
	// (default 250ms). Similar to the JVM's `retry.backoff.ms`.
	Backoff time.Duration `mapstructure:"backoff"`
}
