modulise adj git handling

Author: msanlli

backend/internal/adj/git.go

@@ -0,0 +1,98 @@
+package adj
+
+import (
+	"os"
+
+	"github.com/go-git/go-git/v5"
+	"github.com/go-git/go-git/v5/plumbing"
+)
+
+// WARNING: Doing tricks on it
+func updateRepo(AdjBranch string) error {
+	var repo *git.Repository
+	var err error
+
+	if AdjBranch == "" {
+		// Makes use of submodule
+		return nil
+	} else {
+		if _, err = os.Stat(RepoPath); os.IsNotExist(err) {
+			repo, err = git.PlainClone(RepoPath, false, &git.CloneOptions{
+				URL:           RepoUrl,
+				ReferenceName: plumbing.NewBranchReferenceName(AdjBranch),
+				SingleBranch:  true,
+				Depth:         1,
+			})
+			if err != nil {
+				return err
+			}
+		} else {
+			repo, err = git.PlainOpen(RepoPath)
+			if err != nil {
+				return err
+			}
+		}
+
+		err = repo.Fetch(&git.FetchOptions{
+			RemoteName: "origin",
+			Force:      true,
+		})
+		if err != nil && err != git.NoErrAlreadyUpToDate {
+			return err
+		}
+
+		head, err := repo.Head()
+		if err != nil {
+			return err
+		}
+
+		branch := head.Name().Short()
+
+		worktree, err := repo.Worktree()
+		if err != nil {
+			return err
+		}
+
+		if branch != AdjBranch {
+			localBranchRef := plumbing.NewBranchReferenceName(AdjBranch)
+			_, err = repo.Reference(localBranchRef, false)
+			if err != nil {
+				remoteBranchRef := plumbing.NewRemoteReferenceName("origin", AdjBranch)
+				remoteRef, err2 := repo.Reference(remoteBranchRef, true)
+				if err2 != nil {
+					return err2
+				}
+
+				err = worktree.Checkout(&git.CheckoutOptions{
+					Branch: localBranchRef,
+					Create: true,
+					Force:  true,
+					Hash:   remoteRef.Hash(),
+				})
+				if err != nil {
+					println(err.Error())
+					return err
+				}
+			} else {
+				err = worktree.Checkout(&git.CheckoutOptions{
+					Branch: localBranchRef,
+					Force:  true,
+				})
+			}
+		}
+
+		err = worktree.Pull(&git.PullOptions{
+			RemoteName:   "origin",
+			SingleBranch: true,
+		})
+		if err != nil {
+			if err == git.NoErrAlreadyUpToDate {
+				return nil
+			} else {
+				return err
+			}
+		}
+	}
+
+	return nil
+}