/*
 * Copyright (c) 2013-2014 by Farsight Security, Inc.
 *
 * 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 dnstap

import (
	"io"
	"log"
	"os"

	"github.com/farsightsec/golang-framestream"
)

type FrameStreamInput struct {
	wait    chan bool
	decoder *framestream.Decoder
}

func NewFrameStreamInput(r io.ReadWriter, bi bool) (input *FrameStreamInput, err error) {
	input = new(FrameStreamInput)
	decoderOptions := framestream.DecoderOptions{
		ContentType:   FSContentType,
		Bidirectional: bi,
	}
	input.decoder, err = framestream.NewDecoder(r, &decoderOptions)
	if err != nil {
		return
	}
	input.wait = make(chan bool)
	return
}

func NewFrameStreamInputFromFilename(fname string) (input *FrameStreamInput, err error) {
	file, err := os.Open(fname)
	if err != nil {
		return nil, err
	}
	input, err = NewFrameStreamInput(file, false)
	return
}

func (input *FrameStreamInput) ReadInto(output chan []byte) {
	for {
		buf, err := input.decoder.Decode()
		if err != nil {
			if err != io.EOF {
				log.Printf("framestream.Decoder.Decode() failed: %s\n", err)
			}
			break
		}
		newbuf := make([]byte, len(buf))
		copy(newbuf, buf)
		output <- newbuf
	}
	close(input.wait)
}

func (input *FrameStreamInput) Wait() {
	<-input.wait
}