commit 847ae29a70c74351502c064e9ed9d2fef1c9a456
Author: George Antoniadis <george@noodles.gr>
Date:   Thu Oct 29 21:56:53 2020 +0000

    feat: add manual version file bumping

diff --git a/main.go b/main.go
new file mode 100644
index 0000000..3703f74
--- /dev/null
+++ b/main.go
@@ -0,0 +1,138 @@
+package main
+
+import (
+	"flag"
+	"io/ioutil"
+	"log"
+
+	"github.com/Masterminds/semver"
+	"github.com/davecgh/go-spew/spew"
+	git "github.com/go-git/go-git/v5"
+	"github.com/go-git/go-git/v5/plumbing"
+	"github.com/octago/sflags/gen/gflag"
+)
+
+type (
+	config struct {
+		// action
+		AutodetectBump bool `flag:"bump-auto" desc:"Bump version based on semantic commits"`
+		BumpMajor      bool `flag:"bump-major" desc:"Bump major"`
+		BumpMinor      bool `flag:"bump-minor" desc:"Bump minor"`
+		BumpPatch      bool `flag:"bump-patch" desc:"Bump patch"`
+
+		// version file config
+		FileUpdate bool   `flag:"file-update" desc:"Use version file"`
+		FilePath   string `flag:"file-path" desc:"Version file path"`
+
+		// git tag config
+		GitTagCreate bool
+
+		// version config
+		VersionPrefix string `flag:"version-prefix" desc:"Version prefix"`
+
+		// changelog config
+		ChangelogGenerate     bool
+		ChangelogTemplatePath string
+	}
+)
+
+func detectBump(c *config) error {
+	if !c.AutodetectBump {
+		return nil
+	}
+	repo, err := git.PlainOpen(".")
+	if err != nil {
+		return err
+	}
+	tagrefs, err := repo.Tags()
+	err = tagrefs.ForEach(func(t *plumbing.Reference) error {
+		log.Println(t.Hash(), t.String())
+		return nil
+	})
+	return nil
+}
+
+func fileUpdate(c *config) error {
+	if !c.FileUpdate {
+		return nil
+	}
+	currentVersion := "0.0.0"
+	versionFileBody, err := ioutil.ReadFile(c.FilePath)
+	if err != nil {
+		return err
+	}
+	currentVersion = string(versionFileBody)
+	if currentVersion == "" {
+		currentVersion = c.VersionPrefix + "0.0.0"
+	}
+	newVersion, err := bumpVersion(currentVersion, c)
+	if err != nil {
+		return err
+	}
+	return ioutil.WriteFile(c.FilePath, []byte(newVersion), 0644)
+}
+
+// func changelogGenerate(c *config) error {
+// 	if !c.FileUpdate {
+// 		return nil
+// 	}
+// 	currentVersion := "0.0.0"
+// 	versionFileBody, err := ioutil.ReadFile(c.FilePath)
+// 	if err != nil {
+// 		return err
+// 	}
+// 	currentVersion = string(versionFileBody)
+// 	if currentVersion == "" {
+// 		currentVersion = c.VersionPrefix + "0.0.0"
+// 	}
+// 	newVersion, err := bumpVersion(currentVersion, c)
+// 	if err != nil {
+// 		return err
+// 	}
+// 	return ioutil.WriteFile(c.FilePath, []byte(newVersion), 0644)
+// }
+
+func bumpVersion(currentVersion string, c *config) (string, error) {
+	cleanCurrentVersionString := currentVersion[len(c.VersionPrefix):]
+	cleanCurrentVersion, err := semver.NewVersion(cleanCurrentVersionString)
+	if err != nil {
+		return "", err
+	}
+	cleanNewVersion := *cleanCurrentVersion
+	if c.BumpMajor {
+		cleanNewVersion = cleanNewVersion.IncMajor()
+	}
+	if c.BumpMinor {
+		cleanNewVersion = cleanNewVersion.IncMinor()
+	}
+	if c.BumpPatch {
+		cleanNewVersion = cleanNewVersion.IncPatch()
+	}
+	if cleanCurrentVersion.Equal(&cleanNewVersion) {
+		cleanNewVersion = cleanNewVersion.IncPatch()
+	}
+	return c.VersionPrefix + cleanNewVersion.String(), nil
+}
+
+func main() {
+	c := &config{
+		FilePath:      "VERSION",
+		VersionPrefix: "v",
+	}
+	err := gflag.ParseToDef(c)
+	if err != nil {
+		log.Fatalf("err: %v", err)
+	}
+	flag.Parse()
+	spew.Dump(c)
+
+	actions := []func(*config) error{
+		detectBump,
+		fileUpdate,
+	}
+	for _, action := range actions {
+		if err := action(c); err != nil {
+			log.Fatalf("err: %v", err)
+		}
+	}
+}