| 1 | package main |
| 2 | |
| 3 | import ( |
| 4 | "context" |
| 5 | "errors" |
| 6 | "reasonix/desktop/internal/workspacestate" |
| 7 | "reasonix/internal/session" |
| 8 | "slices" |
| 9 | "strings" |
| 10 | ) |
| 11 | |
| 12 | func (a *App) ForkSession(ref session.SessionRef, turnBoundary string) (session.SessionRef, error) { |
| 13 | plan, err := a.planCanonicalFork(ref, turnBoundary) |
| 14 | if err != nil { |
| 15 | return session.SessionRef{}, err |
| 16 | } |
| 17 | operationID := "fork-" + strings.TrimPrefix(newTabID(), "tab_") |
| 18 | childID := "desktop-" + strings.TrimPrefix(newTabID(), "tab_") |
| 19 | return a.executeCanonicalFork(ref, plan, operationID, childID) |
| 20 | } |
| 21 | |
| 22 | type canonicalForkPlan struct { |
| 23 | workspaceID string |
| 24 | beforeID string |
| 25 | sourceGeneration uint64 |
| 26 | target session.ForkTarget |
| 27 | } |
| 28 | |
| 29 | func (a *App) planCanonicalFork(ref session.SessionRef, turnBoundary string) (canonicalForkPlan, error) { |
| 30 | if err := validateLocalSessionRef(ref); err != nil { |
| 31 | return canonicalForkPlan{}, err |
| 32 | } |
| 33 | state, err := a.workspaceRegistry().Load(context.Background()) |
| 34 | if err != nil { |
| 35 | return canonicalForkPlan{}, err |
| 36 | } |
| 37 | workspaceID, beforeID := "", "" |
| 38 | for _, id := range state.WorkspaceIDs { |
| 39 | workspace := state.Workspaces[id] |
| 40 | for index, sessionID := range workspace.SessionIDs { |
| 41 | if sessionID != ref.SessionID { |
| 42 | continue |
| 43 | } |
| 44 | workspaceID = id |
| 45 | if index+1 < len(workspace.SessionIDs) { |
| 46 | beforeID = workspace.SessionIDs[index+1] |
| 47 | } |
| 48 | break |
| 49 | } |
| 50 | if workspaceID != "" { |
| 51 | break |
| 52 | } |
| 53 | } |
| 54 | if workspaceID == "" { |
| 55 | return canonicalForkPlan{}, workspacestate.ErrSessionNotFound |
| 56 | } |
| 57 | sourceState := state.SessionStates[ref.SessionID] |
| 58 | if sourceState.Lifecycle != workspacestate.Active { |
| 59 | return canonicalForkPlan{}, workspacestate.ErrMutationConflict |
| 60 | } |
| 61 | targets, err := a.desktopSessionService("").ForkTargetSetFor(a.bootContext(), ref) |
| 62 | if err != nil { |
| 63 | return canonicalForkPlan{}, err |
| 64 | } |
| 65 | turnBoundary = strings.TrimSpace(turnBoundary) |
| 66 | var selected session.ForkTarget |
| 67 | if turnBoundary == "" { |
| 68 | for _, target := range slices.Backward(targets.Targets) { |
| 69 | if target.Available { |
| 70 | selected = target |
| 71 | break |
| 72 | } |
| 73 | } |
| 74 | if selected.TurnID == "" { |
| 75 | return canonicalForkPlan{}, errors.New("session has no completed turn to fork") |
| 76 | } |
| 77 | } else { |
| 78 | for _, target := range targets.Targets { |
| 79 | if target.TurnID == turnBoundary { |
| 80 | selected = target |
| 81 | break |
| 82 | } |
| 83 | } |
| 84 | if selected.TurnID == "" || !selected.Available { |
| 85 | reason := selected.Reason |
| 86 | if reason == "" { |
| 87 | reason = session.ForkHistoryUnverifiable |
| 88 | } |
| 89 | return canonicalForkPlan{}, &session.ForkUnavailableError{TurnID: turnBoundary, Reason: reason} |
| 90 | } |
| 91 | } |
| 92 | return canonicalForkPlan{ |
| 93 | workspaceID: workspaceID, beforeID: beforeID, |
| 94 | sourceGeneration: sourceState.Generation, target: selected, |
| 95 | }, nil |
| 96 | } |
| 97 | |
| 98 | func (a *App) executeCanonicalFork(ref session.SessionRef, plan canonicalForkPlan, operationID, childID string) (session.SessionRef, error) { |
| 99 | operationID = strings.TrimSpace(operationID) |
| 100 | childID = strings.TrimSpace(childID) |
| 101 | if operationID == "" || childID == "" { |
| 102 | return session.SessionRef{}, errors.New("fork operation and child identities are required") |
| 103 | } |
| 104 | stateBefore, err := a.workspaceRegistry().Load(a.bootContext()) |
| 105 | if err != nil { |
| 106 | return session.SessionRef{}, err |
| 107 | } |
| 108 | w := stateBefore.Workspaces[plan.workspaceID] |
| 109 | scope := "project" |
| 110 | if plan.workspaceID == workspacestate.GlobalWorkspaceID { |
| 111 | scope = "global" |
| 112 | } |
| 113 | if _, _, err := a.ensureSessionOrganization(scope, w.Root); err != nil { |
| 114 | return session.SessionRef{}, err |
| 115 | } |
| 116 | if err := a.workspaceRegistry().BeginCreate(a.bootContext(), workspacestate.PendingCreate{ |
| 117 | OperationID: operationID, WorkspaceID: plan.workspaceID, SessionID: childID, ParentSessionID: ref.SessionID, |
| 118 | }); err != nil { |
| 119 | return session.SessionRef{}, err |
| 120 | } |
| 121 | forked, err := a.desktopSessionService("").CreateFork(a.bootContext(), session.ForkRequest{ |
| 122 | Source: ref, TurnID: plan.target.TurnID, BoundarySequence: plan.target.BoundarySequence, |
| 123 | OperationID: operationID, ChildID: childID, |
| 124 | }) |
| 125 | if err != nil { |
| 126 | _ = a.workspaceRegistry().AbortCreate(context.Background(), childID) |
| 127 | return session.SessionRef{}, err |
| 128 | } |
| 129 | if _, already := stateBefore.SessionStates[childID]; !already { |
| 130 | // Forks are ordinary independent sessions. Give the child its own title and |
| 131 | // presentation while retaining ParentSessionID in the session header. |
| 132 | parentTitle := "" |
| 133 | if infos, infoErr := listWorkspaceSessionInfo(a.bootContext(), a.desktopSessionService("").Query(), []string{ref.SessionID}); infoErr == nil { |
| 134 | parentTitle = strings.TrimSpace(infos[ref.SessionID].Title) |
| 135 | } |
| 136 | if parentTitle == "" { |
| 137 | if state, stateErr := a.workspaceRegistry().Load(a.bootContext()); stateErr == nil { |
| 138 | parentTitle = strings.TrimSpace(state.Presentation[ref.SessionID].Title) |
| 139 | } |
| 140 | } |
| 141 | if parentTitle == "" { |
| 142 | parentTitle = a.localizedDefaultTopicTitle() |
| 143 | } |
| 144 | forkTitle := parentTitle + a.localizedForkTitleSuffix() |
| 145 | if err := a.desktopSessionService("").SetTitle(a.bootContext(), forked.Child, forkTitle); err != nil { |
| 146 | return session.SessionRef{}, err |
| 147 | } |
| 148 | if err := a.workspaceRegistry().PrepareCreatePresentation(a.bootContext(), childID, workspacestate.Presentation{Title: forkTitle, SortOrder: -1}); err != nil { |
| 149 | return session.SessionRef{}, err |
| 150 | } |
| 151 | } |
| 152 | if err := a.workspaceRegistry().AttachSessionFromSourceIfUnchanged( |
| 153 | a.bootContext(), |
| 154 | operationID, |
| 155 | plan.workspaceID, |
| 156 | childID, |
| 157 | plan.beforeID, |
| 158 | ref.SessionID, |
| 159 | plan.sourceGeneration, |
| 160 | ); err != nil { |
| 161 | // The child transcript is already durable. Preserve the pending create |
| 162 | // so the same operation can finish publication without copying history. |
| 163 | return session.SessionRef{}, err |
| 164 | } |
| 165 | a.emitProjectTreeChanged() |
| 166 | return forked.Child, nil |
| 167 | } |
| 168 | |
| 169 | func (a *App) localizedForkTitleSuffix() string { |
| 170 | switch a.desktopLocale.Load() { |
| 171 | case desktopLocaleEn: |
| 172 | return " · Fork" |
| 173 | case desktopLocaleZhTW: |
| 174 | return " · 分叉" |
| 175 | default: |
| 176 | return " · 分叉" |
| 177 | } |
| 178 | } |
| 179 | |
| 180 | // ForkSessionTarget forks one explicit durable target without staging it into |
| 181 | // the current tab. Legacy-only sources must first be adopted into canonical |
| 182 | // storage so turn boundaries remain verifiable. |
| 183 | func (a *App) ForkSessionTarget(selector SessionSelector, turnBoundary string) (session.SessionRef, error) { |
| 184 | target, err := a.resolveSessionMutationTarget(selector) |
| 185 | if err != nil { |
| 186 | return session.SessionRef{}, err |
| 187 | } |
| 188 | if target.SessionRef.SessionID == "" { |
| 189 | return session.SessionRef{}, newSessionOperationError("unsupported", "This historical session has no verifiable canonical turn boundaries.") |
| 190 | } |
| 191 | plan, err := a.planCanonicalFork(target.SessionRef, turnBoundary) |
| 192 | if err != nil { |
| 193 | return session.SessionRef{}, sessionOperationErrorForTarget(err, target.key(), "") |
| 194 | } |
| 195 | operation, err := a.beginForkOperation(forkOperation{ |
| 196 | Surface: "target", SourceHostID: target.SessionRef.HostID, SourceSessionID: target.SessionRef.SessionID, |
| 197 | TurnID: plan.target.TurnID, BoundarySequence: plan.target.BoundarySequence, |
| 198 | }) |
| 199 | if err != nil { |
| 200 | return session.SessionRef{}, sessionOperationErrorForTarget(err, target.key(), "") |
| 201 | } |
| 202 | if operation.State == "completed" && strings.TrimSpace(operation.ChildSessionID) != "" { |
| 203 | return session.SessionRef{HostID: localDesktopHostID, SessionID: operation.ChildSessionID}, nil |
| 204 | } |
| 205 | childID := "desktop-" + strings.TrimPrefix(operation.OperationID, "fork_") |
| 206 | child, err := a.executeCanonicalFork(target.SessionRef, plan, operation.OperationID, childID) |
| 207 | if err != nil { |
| 208 | var unavailable *session.ForkUnavailableError |
| 209 | if errors.As(err, &unavailable) { |
| 210 | _ = a.discardForkOperation(operation.OperationID) |
| 211 | } |
| 212 | return session.SessionRef{}, sessionOperationErrorForTarget(err, target.key(), operation.OperationID) |
| 213 | } |
| 214 | if err := a.completeForkOperation(operation.OperationID, child.SessionID); err != nil { |
| 215 | return session.SessionRef{}, sessionOperationErrorForTarget(err, target.key(), operation.OperationID) |
| 216 | } |
| 217 | return child, nil |
| 218 | } |
| 219 |