package bug import ( "encoding/json" "fmt" "reflect" "github.com/MichaelMure/git-bug/repository" "github.com/MichaelMure/git-bug/util/git" ) const formatVersion = 1 // OperationPack represent an ordered set of operation to apply // to a Bug. These operations are stored in a single Git commit. // // These commits will be linked together in a linear chain of commits // inside Git to form the complete ordered chain of operation to // apply to get the final state of the Bug type OperationPack struct { Operations []Operation // Private field so not serialized by gob commitHash git.Hash } var operations map[OperationType]reflect.Type func Register(t OperationType, op interface{}) { if operations == nil { operations = make(map[OperationType]reflect.Type) } operations[t] = reflect.TypeOf(op) } func (opp *OperationPack) MarshalJSON() ([]byte, error) { return json.Marshal(struct { Version uint `json:"version"` Operations []Operation `json:"ops"` }{ Version: formatVersion, Operations: opp.Operations, }) } func (opp *OperationPack) UnmarshalJSON(data []byte) error { aux := struct { Version uint `json:"version"` Operations []json.RawMessage `json:"ops"` }{} if err := json.Unmarshal(data, &aux); err != nil { return err } if aux.Version != formatVersion { return fmt.Errorf("unknown format version %v", aux.Version) } for _, raw := range aux.Operations { var t struct { OperationType OperationType `json:"type"` } if err := json.Unmarshal(raw, &t); err != nil { return err } opType, ok := operations[t.OperationType] if !ok { return fmt.Errorf("unknown operation type %v", t.OperationType) } op := reflect.New(opType).Interface() if err := json.Unmarshal(raw, op); err != nil { return err } deref := reflect.ValueOf(op).Elem().Interface() opp.Operations = append(opp.Operations, deref.(Operation)) } return nil } // Append a new operation to the pack func (opp *OperationPack) Append(op Operation) { opp.Operations = append(opp.Operations, op) } // IsEmpty tell if the OperationPack is empty func (opp *OperationPack) IsEmpty() bool { return len(opp.Operations) == 0 } // IsValid tell if the OperationPack is considered valid func (opp *OperationPack) IsValid() bool { return !opp.IsEmpty() } // Write will serialize and store the OperationPack as a git blob and return // its hash func (opp *OperationPack) Write(repo repository.Repo) (git.Hash, error) { data, err := json.Marshal(opp) if err != nil { return "", err } hash, err := repo.StoreData(data) if err != nil { return "", err } return hash, nil } // Make a deep copy func (opp *OperationPack) Clone() OperationPack { clone := OperationPack{ Operations: make([]Operation, len(opp.Operations)), commitHash: opp.commitHash, } for i, op := range opp.Operations { clone.Operations[i] = op } return clone }