package common

import (
	"bytes"
	"encoding/json"
	"strings"

	"github.com/sirupsen/logrus"
	"github.com/spf13/cast"
)

func FormatJson(data string) (string, error) {
	var out bytes.Buffer
	err := json.Indent(&out, []byte(data), "", "    ")
	return out.String(), err
}

func SubStr(str string, start int, length int) (result string) {
	s := []rune(str)
	total := len(s)
	if total == 0 {
		return
	}
	// 允许从尾部开始计算
	if start < 0 {
		start = total + start
		if start < 0 {
			return
		}
	}
	if start > total {
		return
	}
	// 到末尾
	if length < 0 {
		length = total
	}

	end := start + length
	if end > total {
		result = string(s[start:])
	} else {
		result = string(s[start:end])
	}

	return
}

// 是否升级
func IsUpgrade(newVersion, oldVersion string) bool {
	nvArr := strings.SplitN(newVersion, ".", 3)
	if len(nvArr) != 3 {
		logrus.Error("new version format err")
		return false
	}

	ovArr := strings.SplitN(oldVersion, ".", 3)
	if len(ovArr) != 3 {
		logrus.Error("old version format err")
		return false
	}

	nvNum := cast.ToInt(nvArr[0])*100 + cast.ToInt(nvArr[1])*10 + cast.ToInt(nvArr[2])
	ovNum := cast.ToInt(ovArr[0])*100 + cast.ToInt(ovArr[1])*10 + cast.ToInt(ovArr[2])

	if nvNum > ovNum {
		return true
	}
	return false
}