version.go

package version

import (
	"strings"
	"strconv"
)

const (
	major  = 1
	minor  = 4
	bugfix = 1
)

type Version struct {
	major int
	minor int
	bugfix int
}

var version Version = FromInt(major, minor, bugfix)

func FromInt(major, minor, bugfix int) Version {
	return Version{major, minor, bugfix}
}

// Format: "x.y.z"
func FromString(s string) (Version, error) {
	f := strings.Split(s, ".")  
	major, _ := strconv.Atoi(f[0])
	minor, _ := strconv.Atoi(f[1])
	bugfix, _ := strconv.Atoi(f[2])
	return Version{major, minor, bugfix}, nil
}

func Get() Version {
	return version
}

func (v Version) String() string {
	return strconv.Itoa(v.major)+"."+strconv.Itoa(v.minor)+"."+strconv.Itoa(v.bugfix)
}

func (v Version) StringWithoutBugfix() string {
	return strconv.Itoa(v.major)+"."+strconv.Itoa(v.minor)+".x"
}

// Returns true if v is older than candidate
func (v Version) IsOlder(candidate Version) bool {
	v1 := v.getMajorMinor()
	v2 := candidate.getMajorMinor()
	if v1 > v2 {
		return false
	} else if v1 < v2 {
		return true
	} else {
		bugfix1 := v.getBugfix()
		bugfix2 := candidate.getBugfix()
		return bugfix1 < bugfix2
	}
}

// Returns true if v is compatible with candidate
func (v Version) IsCompatible(candidate Version) bool {
	v1 := v.getMajorMinor()
	v2 := candidate.getMajorMinor()
	return v1 == v2
}

func (v Version) getMajorMinorAsString() string {
	return strconv.Itoa(v.major)+strconv.Itoa(v.minor)
}

func (v Version) getMajorMinor() int {
	n, _ := strconv.Atoi(v.getMajorMinorAsString())
	return n
}

func (v Version) getBugfix() int {
	return v.bugfix
}