package config

import (
	"errors"
	"io/ioutil"
	"os"
	"path"
	"strconv"

	"git.trj.tw/golang/utils"
	yaml "gopkg.in/yaml.v2"
)

// Config -
type Config struct {
	Port int `yaml:"port"`
	AWS  struct {
		SharedConfig bool   `yaml:"shared_config"`
		AccessKey    string `yaml:"access_key"`
		SecretKey    string `yaml:"secret_key"`
	} `yaml:"aws"`
}

var conf *Config

// LoadConfig -
func LoadConfig(p ...string) (err error) {
	fp := ""
	if len(p) > 0 && len(p[0]) > 0 {
		fp = p[0]
	} else {
		wd, err := os.Getwd()
		if err != nil {
			return err
		}
		fp = path.Join(wd, "config.yml")
	}

	fp = utils.ParsePath(fp)
	if exists := utils.CheckExists(fp, false); !exists {
		return errors.New("config file not exists")
	}
	data, err := ioutil.ReadFile(fp)
	if err != nil {
		return err
	}

	conf = &Config{}
	err = yaml.Unmarshal(data, conf)
	if err != nil {
		return err
	}
  envOverride()

	return
}

func envOverride() {
	var str string
	// set port
	str = os.Getenv("PORT")
	if len(str) > 0 {
		num, err := strconv.Atoi(str)
		if err == nil && num > 0 && num < 65536 {
			conf.Port = num
		}
	}

	// set aws use shared config
	str = os.Getenv("AWS_SHARED_CONF")
	if len(str) > 0 {
		if str == "1" {
			conf.AWS.SharedConfig = true
		} else if str == "0" {
			conf.AWS.SharedConfig = false
		}
	}

	// set aws access key
	str = os.Getenv("AWS_ACCESS_KEY")
	if len(str) > 0 {
		conf.AWS.AccessKey = str
	}

	// set aws secret key
	str = os.Getenv("AWS_SECRET_KEY")
	if len(str) > 0 {
		conf.AWS.SecretKey = str
	}
}

// GetConfig -
func GetConfig() *Config {
	return conf
}