bug: add a new SetMetadataOperation to retroactively tag operations

1 files changed, 72 insertions, 0 deletions

diff --git a/bug/op_set_metadata.go b/bug/op_set_metadata.go
new file mode 100644
index 00000000..68cf1d51
--- /dev/null
+++ b/bug/op_set_metadata.go
@@ -0,0 +1,72 @@
+package bug
+
+import "github.com/MichaelMure/git-bug/util/git"
+
+var _ Operation = &SetMetadataOperation{}
+
+type SetMetadataOperation struct {
+	OpBase
+	Target      git.Hash          `json:"target"`
+	NewMetadata map[string]string `json:"new_metadata"`
+}
+
+func (op *SetMetadataOperation) base() *OpBase {
+	return &op.OpBase
+}
+
+func (op *SetMetadataOperation) Hash() (git.Hash, error) {
+	return hashOperation(op)
+}
+
+func (op *SetMetadataOperation) Apply(snapshot *Snapshot) {
+	for _, target := range snapshot.Operations {
+		hash, err := target.Hash()
+		if err != nil {
+			// Should never error unless a programming error happened
+			// (covered in OpBase.Validate())
+			panic(err)
+		}
+
+		if hash == op.Target {
+			base := target.base()
+
+			if base.extraMetadata == nil {
+				base.extraMetadata = make(map[string]string)
+			}
+
+			for key, val := range op.NewMetadata {
+				if _, exist := base.extraMetadata[key]; !exist {
+					base.extraMetadata[key] = val
+				}
+			}
+
+			return
+		}
+	}
+}
+
+func (op *SetMetadataOperation) Validate() error {
+	if err := opBaseValidate(op, SetMetadataOp); err != nil {
+		return err
+	}
+
+	return nil
+}
+
+func NewSetMetadataOp(author Person, unixTime int64, target git.Hash, newMetadata map[string]string) *SetMetadataOperation {
+	return &SetMetadataOperation{
+		OpBase:      newOpBase(SetMetadataOp, author, unixTime),
+		Target:      target,
+		NewMetadata: newMetadata,
+	}
+}
+
+// Convenience function to apply the operation
+func SetMetadata(b Interface, author Person, unixTime int64, target git.Hash, newMetadata map[string]string) (*SetMetadataOperation, error) {
+	SetMetadataOp := NewSetMetadataOp(author, unixTime, target, newMetadata)
+	if err := SetMetadataOp.Validate(); err != nil {
+		return nil, err
+	}
+	b.Append(SetMetadataOp)
+	return SetMetadataOp, nil
+}