migrate from github

internal/repository/document_version_repo/create.go

@@ -0,0 +1,43 @@
+package document_version_repo
+
+import (
+	"github.com/XingfenD/yoresee_doc/internal/model"
+	"gorm.io/gorm"
+)
+
+type DocumentVersionCreateOperation struct {
+	repo       *DocumentVersionRepository
+	docVersion *model.DocumentVersion
+	tx         *gorm.DB
+}
+
+func (repo *DocumentVersionRepository) Create(docVersion *model.DocumentVersion) *DocumentVersionCreateOperation {
+	return &DocumentVersionCreateOperation{
+		repo:       repo,
+		docVersion: docVersion,
+	}
+}
+
+func (op *DocumentVersionCreateOperation) WithTx(tx *gorm.DB) *DocumentVersionCreateOperation {
+	op.tx = tx
+	return op
+}
+
+func (op *DocumentVersionCreateOperation) Exec() error {
+	if op.tx == nil {
+		op.tx = op.repo.db
+	}
+
+	var maxVersion int
+	err := op.tx.Model(&model.DocumentVersion{}).
+		Where("document_id = ?", op.docVersion.DocumentID).
+		Select("COALESCE(MAX(version), 0)").
+		Scan(&maxVersion).Error
+	if err != nil {
+		return err
+	}
+
+	op.docVersion.Version = maxVersion + 1
+
+	return op.tx.Create(op.docVersion).Error
+}