// +build linux windows,!arm darwin
// +build 386 amd64 arm arm64

// Package codec Slik编码核心模块
package codec

import (
	"io/ioutil"
	"os"
	"os/exec"
	"path"

	"github.com/pkg/errors"
	"github.com/wdvxdr1123/go-silk"
)

const (
	silkCachePath = "data/cache"
)

//EncodeToSilk 将音频编码为Silk
func EncodeToSilk(record []byte, tempName string, useCache bool) (silkWav []byte, err error) {
	// 1. 写入缓存文件
	rawPath := path.Join(silkCachePath, tempName+".wav")
	err = ioutil.WriteFile(rawPath, record, os.ModePerm)
	if err != nil {
		return nil, errors.Wrap(err, "write temp file error")
	}
	defer os.Remove(rawPath)

	// 2.转换pcm
	pcmPath := path.Join(silkCachePath, tempName+".pcm")
	cmd := exec.Command("ffmpeg", "-i", rawPath, "-f", "s16le", "-ar", "24000", "-ac", "1", pcmPath)
	if err = cmd.Run(); err != nil {
		return nil, errors.Wrap(err, "convert pcm file error")
	}
	defer os.Remove(pcmPath)

	// 3. 转silk
	pcm, err := ioutil.ReadFile(pcmPath)
	if err != nil {
		return nil, errors.Wrap(err, "read pcm file err")
	}
	silkWav, err = silk.EncodePcmBuffToSilk(pcm, 24000, 24000, true)
	if err != nil {
		return nil, errors.Wrap(err, "silk encode error")
	}
	if useCache {
		silkPath := path.Join(silkCachePath, tempName+".silk")
		err = ioutil.WriteFile(silkPath, silkWav, 0666)
	}
	return
}