// Licensed to Elasticsearch B.V. under one or more contributor
// license agreements. See the NOTICE file distributed with
// this work for additional information regarding copyright
// ownership. Elasticsearch B.V. licenses this file to you 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 format

import (
	"errors"

	"github.com/elastic/beats/v7/libbeat/beat"
	"github.com/elastic/beats/v7/libbeat/common"
	"github.com/elastic/beats/v7/libbeat/common/fmtstr"
	"github.com/elastic/beats/v7/libbeat/outputs/codec"
)

type Encoder struct {
	Format *fmtstr.EventFormatString
}

type Config struct {
	String *fmtstr.EventFormatString `config:"string" validate:"required"`
}

func init() {
	codec.RegisterType("format", func(_ beat.Info, cfg *common.Config) (codec.Codec, error) {
		config := Config{}
		if cfg == nil {
			return nil, errors.New("empty format codec configuration")
		}

		if err := cfg.Unpack(&config); err != nil {
			return nil, err
		}

		return New(config.String), nil
	})
}

func New(fmt *fmtstr.EventFormatString) *Encoder {
	return &Encoder{fmt}
}

func (e *Encoder) Encode(_ string, event *beat.Event) ([]byte, error) {
	return e.Format.RunBytes(event)
}
