| 1 | package agent |
| 2 | |
| 3 | import ( |
| 4 | "context" |
| 5 | "crypto/rand" |
| 6 | "encoding/hex" |
| 7 | "encoding/json" |
| 8 | "errors" |
| 9 | "fmt" |
| 10 | "os" |
| 11 | "path/filepath" |
| 12 | "sort" |
| 13 | "strings" |
| 14 | "sync/atomic" |
| 15 | "time" |
| 16 | |
| 17 | fileencoding "reasonix/internal/fileutil/encoding" |
| 18 | "reasonix/internal/store" |
| 19 | ) |
| 20 | |
| 21 | // ErrSessionTitleChanged reports that a conditional rename observed a newer |
| 22 | // custom title and left it untouched. |
| 23 | var ErrSessionTitleChanged = errors.New("session title changed") |
| 24 | |
| 25 | // BranchMeta is the small sidecar record that turns flat session files into a |
| 26 | // navigable conversation tree. The conversation itself remains in the .jsonl |
| 27 | // file; metadata lives beside it at <session>.meta. |
| 28 | type BranchMeta struct { |
| 29 | ID string `json:"id"` |
| 30 | Name string `json:"name,omitempty"` |
| 31 | ParentID string `json:"parent_id,omitempty"` |
| 32 | ForkTurn int `json:"fork_turn,omitempty"` |
| 33 | ForkMessageIndex int `json:"fork_message_index,omitempty"` |
| 34 | CreatedAt time.Time `json:"created_at"` |
| 35 | UpdatedAt time.Time `json:"updated_at"` |
| 36 | Scope string `json:"scope,omitempty"` |
| 37 | WorkspaceRoot string `json:"workspace_root,omitempty"` |
| 38 | TopicID string `json:"topic_id,omitempty"` |
| 39 | TopicTitle string `json:"topic_title,omitempty"` |
| 40 | CustomTitle string `json:"custom_title,omitempty"` |
| 41 | // TitleRevision is an opaque mutation identity for CustomTitle. It is |
| 42 | // independent from the transcript Revision: saving the same title again |
| 43 | // still advances this token so a delayed AI completion cannot pass an |
| 44 | // A→B→A value comparison. |
| 45 | TitleRevision string `json:"title_revision,omitempty"` |
| 46 | Model string `json:"model,omitempty"` |
| 47 | ModelIdentity string `json:"model_identity,omitempty"` |
| 48 | // TokenMode and AgentPreset are deprecated dual-write fields derived from |
| 49 | // QualityFloor; delivery writes "delivery", standard writes "full"/"". |
| 50 | TokenMode string `json:"token_mode,omitempty"` |
| 51 | AgentPreset string `json:"agent_preset,omitempty"` |
| 52 | // QualityFloor is the session delivery floor (standard|delivery). Loading |
| 53 | // a meta without it maps legacy AgentPreset/TokenMode "delivery" here. |
| 54 | QualityFloor string `json:"quality_floor,omitempty"` |
| 55 | Mode string `json:"mode,omitempty"` |
| 56 | ToolApprovalMode string `json:"tool_approval_mode,omitempty"` |
| 57 | Goal string `json:"goal,omitempty"` |
| 58 | Recovered bool `json:"recovered,omitempty"` |
| 59 | // VersionKind separates ordinary transcripts, recovery copies, and |
| 60 | // session-backed subagents. Older sidecars infer recovery from Recovered. |
| 61 | VersionKind SessionVersionKind `json:"version_kind,omitempty"` |
| 62 | VersionState SessionVersionState `json:"version_state,omitempty"` |
| 63 | ParentConversationID string `json:"parent_conversation_id,omitempty"` |
| 64 | ParentVersionID string `json:"parent_version_id,omitempty"` |
| 65 | BaseRevision int64 `json:"base_revision,omitempty"` |
| 66 | DiskRevision int64 `json:"disk_revision,omitempty"` |
| 67 | RecoveryReason string `json:"recovery_reason,omitempty"` |
| 68 | RecoveryDigest string `json:"recovery_digest,omitempty"` |
| 69 | // RecoveryDepth is 1 for new stable recovery branches. Older nested |
| 70 | // files may still carry a larger historical value. |
| 71 | RecoveryDepth int `json:"recovery_depth,omitempty"` |
| 72 | // RecoveryPreferred is a user's explicit choice among genuinely diverged |
| 73 | // recovery leaves. It changes the default open target, but never authorizes |
| 74 | // deletion and is cleared automatically if that leaf is no longer valid. |
| 75 | RecoveryPreferred bool `json:"recovery_preferred,omitempty"` |
| 76 | RecoveryPreferredDigest string `json:"recovery_preferred_digest,omitempty"` |
| 77 | Revision int64 `json:"revision,omitempty"` |
| 78 | ContentDigest string `json:"content_digest,omitempty"` |
| 79 | WriterID string `json:"writer_id,omitempty"` |
| 80 | // SchemaVersion identifies which BranchMeta version last wrote content-derived |
| 81 | // listing fields (Turns/Preview). Only snapshot/Fork/Branch stamp it; readers |
| 82 | // use it to distinguish authoritative current counts from legacy zeros. |
| 83 | SchemaVersion int `json:"schema_version,omitempty"` |
| 84 | // Turns/Preview accelerate listings; the listing identity binds them to the |
| 85 | // transcript generation they describe, so a failed projection write makes |
| 86 | // old counts visibly stale instead of silently reusable. |
| 87 | Turns int `json:"turns,omitempty"` |
| 88 | Preview string `json:"preview,omitempty"` |
| 89 | ListingRevision int64 `json:"listing_revision,omitempty"` |
| 90 | ListingContentDigest string `json:"listing_content_digest,omitempty"` |
| 91 | InFlightTurn *InFlightTurnMeta `json:"in_flight_turn,omitempty"` |
| 92 | // HeadID and its companions mirror the schema-2 log's selected head for |
| 93 | // listings that must not replay the log; they are absent for schema 1. |
| 94 | HeadID string `json:"head_id,omitempty"` |
| 95 | HeadCount int `json:"head_count,omitempty"` |
| 96 | LogSchema int `json:"log_schema,omitempty"` |
| 97 | LogGeneration int64 `json:"log_generation,omitempty"` |
| 98 | } |
| 99 | |
| 100 | // SessionVersionKind is the durable identity class of a physical transcript. |
| 101 | // It is intentionally separate from Recovered for compatibility with older |
| 102 | // sidecars and from subagent metadata, which carries richer child lifecycle. |
| 103 | type SessionVersionKind string |
| 104 | |
| 105 | const ( |
| 106 | VersionNormal SessionVersionKind = "normal" |
| 107 | VersionRecovery SessionVersionKind = "recovery" |
| 108 | VersionSubagent SessionVersionKind = "subagent" |
| 109 | ) |
| 110 | |
| 111 | type SessionVersionState string |
| 112 | |
| 113 | const ( |
| 114 | VersionActive SessionVersionState = "active" |
| 115 | VersionPending SessionVersionState = "pending" |
| 116 | VersionResolved SessionVersionState = "resolved" |
| 117 | VersionTrashed SessionVersionState = "trashed" |
| 118 | ) |
| 119 | |
| 120 | func (m BranchMeta) EffectiveVersionKind() SessionVersionKind { |
| 121 | if m.VersionKind != "" { |
| 122 | return m.VersionKind |
| 123 | } |
| 124 | if m.Recovered { |
| 125 | return VersionRecovery |
| 126 | } |
| 127 | return VersionNormal |
| 128 | } |
| 129 | |
| 130 | func (m BranchMeta) EffectiveVersionState() SessionVersionState { |
| 131 | if m.VersionState != "" { |
| 132 | return m.VersionState |
| 133 | } |
| 134 | return VersionActive |
| 135 | } |
| 136 | |
| 137 | const ( |
| 138 | // branchMetaCountsInitialVersion introduced content-derived Turns/Preview. |
| 139 | // Positive counts from this version remain authoritative. |
| 140 | branchMetaCountsInitialVersion = 1 |
| 141 | // BranchMetaCountsVersion certifies that zero turns came from a successful, |
| 142 | // error-aware decode. Version 1 could cache a preview failure as zero turns. |
| 143 | BranchMetaCountsVersion = 2 |
| 144 | ) |
| 145 | |
| 146 | // InFlightTurnMeta records the message-log boundary for a foreground turn that |
| 147 | // has started but not yet reached TurnDone. If the process exits mid-turn, a |
| 148 | // later resume can strip the partial assistant/tool tail without guessing. |
| 149 | type InFlightTurnMeta struct { |
| 150 | // ID makes marker cleanup compare-and-clear. Older sidecars omit it and are |
| 151 | // handled by the legacy index/time recovery path. |
| 152 | ID string `json:"id,omitempty"` |
| 153 | StartMessageIndex int `json:"start_message_index"` |
| 154 | PreserveUser bool `json:"preserve_user"` |
| 155 | StartedAt time.Time `json:"started_at"` |
| 156 | // StartRevision and StartDigest bind the legacy array boundary to the |
| 157 | // persisted transcript that existed when the turn began. |
| 158 | StartRevision int64 `json:"start_revision,omitempty"` |
| 159 | StartDigest string `json:"start_digest,omitempty"` |
| 160 | // CommitDigest is written before the final turn snapshot. If recovery sees |
| 161 | // this exact transcript on disk, the snapshot committed and only marker |
| 162 | // cleanup was interrupted; no message recovery is necessary. |
| 163 | CommitDigest string `json:"commit_digest,omitempty"` |
| 164 | // HeadID marks a schema-2 turn whose begin/end markers live in the log |
| 165 | // rather than in this sidecar; such markers are never persisted here. |
| 166 | HeadID string `json:"head_id,omitempty"` |
| 167 | } |
| 168 | |
| 169 | func (m BranchMeta) DefaultScope() string { |
| 170 | switch m.Scope { |
| 171 | case "project": |
| 172 | return "project" |
| 173 | default: |
| 174 | return "global" |
| 175 | } |
| 176 | } |
| 177 | |
| 178 | // BranchInfo combines sidecar metadata with the session file details needed for |
| 179 | // pickers and tree rendering. |
| 180 | type BranchInfo struct { |
| 181 | BranchMeta |
| 182 | Path string |
| 183 | ModTime time.Time |
| 184 | Preview string |
| 185 | Turns int |
| 186 | // HeadID and HeadKind are set for a head inside a schema-2 log; Path is |
| 187 | // then the log the head lives in and ID is the head id. |
| 188 | HeadID string |
| 189 | HeadKind string |
| 190 | } |
| 191 | |
| 192 | func BranchID(path string) string { |
| 193 | if path == "" { |
| 194 | return "" |
| 195 | } |
| 196 | base := filepath.Base(path) |
| 197 | if ext := filepath.Ext(base); ext != "" { |
| 198 | base = strings.TrimSuffix(base, ext) |
| 199 | } |
| 200 | return base |
| 201 | } |
| 202 | |
| 203 | func BranchMetaPath(sessionPath string) string { |
| 204 | return store.SessionMeta(sessionPath) |
| 205 | } |
| 206 | |
| 207 | func LoadBranchMeta(sessionPath string) (BranchMeta, bool, error) { |
| 208 | metaPath := BranchMetaPath(sessionPath) |
| 209 | if metaPath == "" { |
| 210 | return BranchMeta{}, false, nil |
| 211 | } |
| 212 | b, err := fileencoding.ReadFileUTF8(metaPath) |
| 213 | if err != nil { |
| 214 | if os.IsNotExist(err) { |
| 215 | return BranchMeta{}, false, nil |
| 216 | } |
| 217 | return BranchMeta{}, false, err |
| 218 | } |
| 219 | var m BranchMeta |
| 220 | if err := json.Unmarshal(b, &m); err != nil { |
| 221 | // Treat an all-NUL/JSON-whitespace sidecar as a torn write so callers |
| 222 | // rebuild it; retain errors for partial JSON to avoid swallowing corruption. |
| 223 | if metaIsUnparseableAsAbsent(b) { |
| 224 | return BranchMeta{}, false, nil |
| 225 | } |
| 226 | return BranchMeta{}, false, fmt.Errorf("decode branch meta %s: %w", metaPath, err) |
| 227 | } |
| 228 | if m.ID == "" { |
| 229 | m.ID = BranchID(sessionPath) |
| 230 | } |
| 231 | m.sanitizeDisplayFields() |
| 232 | return m, true, nil |
| 233 | } |
| 234 | |
| 235 | // metaIsUnparseableAsAbsent recognizes an empty or all-NUL/JSON-whitespace torn |
| 236 | // write that is safe to rebuild; other bytes indicate genuine corruption. |
| 237 | func metaIsUnparseableAsAbsent(b []byte) bool { |
| 238 | if len(b) == 0 { |
| 239 | return true |
| 240 | } |
| 241 | for _, c := range b { |
| 242 | if c != 0x00 && c != ' ' && c != '\t' && c != '\r' && c != '\n' { |
| 243 | return false |
| 244 | } |
| 245 | } |
| 246 | return true |
| 247 | } |
| 248 | |
| 249 | // sanitizeDisplayFields cleans persisted display strings that older builds |
| 250 | // polluted with internal wrappers (memory-compiler execution contracts, |
| 251 | // transient blocks) — #5666. Every reader goes through LoadBranchMeta, so this |
| 252 | // is the single boundary; UserPreviewText is a no-op on clean text, and a |
| 253 | // field that was pure wrapper falls back to empty so callers use their normal |
| 254 | // fallbacks (preview, default title). |
| 255 | func (m *BranchMeta) sanitizeDisplayFields() { |
| 256 | m.TopicTitle = sanitizeStoredDisplayText(m.TopicTitle) |
| 257 | m.CustomTitle = sanitizeStoredDisplayText(m.CustomTitle) |
| 258 | m.Preview = sanitizeStoredDisplayText(m.Preview) |
| 259 | } |
| 260 | |
| 261 | func sanitizeStoredDisplayText(s string) string { |
| 262 | if strings.TrimSpace(s) == "" { |
| 263 | return strings.TrimSpace(s) |
| 264 | } |
| 265 | return UserPreviewText(s) |
| 266 | } |
| 267 | |
| 268 | // branchMetaReadBackoffs paces the re-reads of a branch-meta sidecar that |
| 269 | // failed to load. On Windows fileutil.ReplaceFile can fall back to a |
| 270 | // non-atomic in-place copy, so a concurrent reader may catch the sidecar |
| 271 | // half-written (an open/read error or truncated JSON). Those tears heal in |
| 272 | // milliseconds; a few short retries separate them from real corruption. |
| 273 | var branchMetaReadBackoffs = []time.Duration{20 * time.Millisecond, 50 * time.Millisecond, 100 * time.Millisecond} |
| 274 | |
| 275 | // loadBranchMetaRetry reads the branch-meta sidecar like LoadBranchMeta but |
| 276 | // retries transient failures (I/O errors and undecodable JSON) before giving |
| 277 | // up. A missing sidecar is a legitimate state — a session that has never |
| 278 | // recorded meta — and returns ok=false immediately without retrying. |
| 279 | func loadBranchMetaRetry(sessionPath string) (BranchMeta, bool, error) { |
| 280 | var lastErr error |
| 281 | for attempt := 0; ; attempt++ { |
| 282 | meta, ok, err := LoadBranchMeta(sessionPath) |
| 283 | if err == nil { |
| 284 | return meta, ok, nil |
| 285 | } |
| 286 | lastErr = err |
| 287 | if attempt >= len(branchMetaReadBackoffs) { |
| 288 | return BranchMeta{}, false, lastErr |
| 289 | } |
| 290 | time.Sleep(branchMetaReadBackoffs[attempt]) |
| 291 | } |
| 292 | } |
| 293 | |
| 294 | func SaveBranchMeta(sessionPath string, m BranchMeta) error { |
| 295 | return UpdateBranchMeta(sessionPath, true, func(current *BranchMeta) error { |
| 296 | // SaveBranchMeta is the compatibility full-record writer. Callers that |
| 297 | // intentionally supply CustomTitle must still be able to change it; the |
| 298 | // cross-process lock held by UpdateBranchMeta makes that replacement |
| 299 | // authoritative. Transcript/listing writers use saveBranchMeta below, |
| 300 | // which preserves the title fields from the latest sidecar. |
| 301 | preserveBranchMetaPersistence(&m, *current, false) |
| 302 | *current = m |
| 303 | return nil |
| 304 | }) |
| 305 | } |
| 306 | |
| 307 | func SaveBranchMetaPreserveUpdated(sessionPath string, m BranchMeta) error { |
| 308 | return UpdateBranchMeta(sessionPath, false, func(current *BranchMeta) error { |
| 309 | preserveBranchMetaPersistence(&m, *current, false) |
| 310 | *current = m |
| 311 | return nil |
| 312 | }) |
| 313 | } |
| 314 | |
| 315 | // SaveBranchMetaPreserveUpdatedLocked is for callers that already hold |
| 316 | // LockSessionMetaPath for a larger read-modify-write transaction. |
| 317 | func SaveBranchMetaPreserveUpdatedLocked(sessionPath string, m BranchMeta) error { |
| 318 | return saveBranchMetaContextMode(context.Background(), sessionPath, m, false, false) |
| 319 | } |
| 320 | |
| 321 | func saveBranchMeta(sessionPath string, m BranchMeta, touchUpdated bool) error { |
| 322 | return saveBranchMetaContextMode(context.Background(), sessionPath, m, touchUpdated, true) |
| 323 | } |
| 324 | |
| 325 | func saveBranchMetaContext(ctx context.Context, sessionPath string, m BranchMeta, touchUpdated bool) error { |
| 326 | return saveBranchMetaContextMode(ctx, sessionPath, m, touchUpdated, true) |
| 327 | } |
| 328 | |
| 329 | func saveBranchMetaTitle(sessionPath string, m BranchMeta) error { |
| 330 | return saveBranchMetaContextMode(context.Background(), sessionPath, m, false, false) |
| 331 | } |
| 332 | |
| 333 | func saveBranchMetaContextMode(ctx context.Context, sessionPath string, m BranchMeta, touchUpdated, preserveTitle bool) error { |
| 334 | metaPath := BranchMetaPath(sessionPath) |
| 335 | if metaPath == "" { |
| 336 | return fmt.Errorf("empty session path") |
| 337 | } |
| 338 | now := time.Now().UTC() |
| 339 | if m.ID == "" { |
| 340 | m.ID = BranchID(sessionPath) |
| 341 | } |
| 342 | if m.CreatedAt.IsZero() { |
| 343 | m.CreatedAt = now |
| 344 | } |
| 345 | if touchUpdated { |
| 346 | m.UpdatedAt = now |
| 347 | } else if m.UpdatedAt.IsZero() { |
| 348 | if info, err := os.Stat(sessionPath); err == nil { |
| 349 | m.UpdatedAt = info.ModTime().UTC() |
| 350 | } else { |
| 351 | m.UpdatedAt = now |
| 352 | } |
| 353 | } |
| 354 | if existing, ok, err := LoadBranchMeta(sessionPath); err == nil && ok { |
| 355 | preserveBranchMetaPersistence(&m, existing, preserveTitle) |
| 356 | } |
| 357 | if err := os.MkdirAll(filepath.Dir(metaPath), 0o755); err != nil { |
| 358 | return err |
| 359 | } |
| 360 | b, err := marshalJSONIndentContext(ctx, m) |
| 361 | if err != nil { |
| 362 | return err |
| 363 | } |
| 364 | b = append(b, '\n') |
| 365 | return atomicWriteFileContext(ctx, metaPath, ".branch.*.tmp", "branch-meta", b, 0o600, false) |
| 366 | } |
| 367 | |
| 368 | func preserveBranchMetaPersistence(next *BranchMeta, existing BranchMeta, preserveTitle ...bool) { |
| 369 | if next == nil { |
| 370 | return |
| 371 | } |
| 372 | // Title metadata is owned by the title mutation path, not by transcript |
| 373 | // snapshots or listing projection refreshes. A stale in-memory BranchMeta |
| 374 | // must never roll it back while preserving newer transcript fields. |
| 375 | if len(preserveTitle) == 0 || preserveTitle[0] { |
| 376 | next.CustomTitle = existing.CustomTitle |
| 377 | next.TitleRevision = existing.TitleRevision |
| 378 | } |
| 379 | if existing.Revision > next.Revision { |
| 380 | next.Revision = existing.Revision |
| 381 | next.ContentDigest = existing.ContentDigest |
| 382 | next.WriterID = existing.WriterID |
| 383 | preserveBranchMetaListingProjection(next, existing) |
| 384 | return |
| 385 | } |
| 386 | if existing.Revision == next.Revision { |
| 387 | if strings.TrimSpace(next.ContentDigest) == "" { |
| 388 | next.ContentDigest = existing.ContentDigest |
| 389 | } |
| 390 | if strings.TrimSpace(next.WriterID) == "" { |
| 391 | next.WriterID = existing.WriterID |
| 392 | } |
| 393 | if next.ListingRevision == 0 && existing.ListingRevision != 0 || |
| 394 | strings.TrimSpace(next.ListingContentDigest) == "" && strings.TrimSpace(existing.ListingContentDigest) != "" { |
| 395 | preserveBranchMetaListingProjection(next, existing) |
| 396 | } |
| 397 | } |
| 398 | } |
| 399 | |
| 400 | func preserveBranchMetaListingProjection(next *BranchMeta, existing BranchMeta) { |
| 401 | next.SchemaVersion = existing.SchemaVersion |
| 402 | next.Turns = existing.Turns |
| 403 | next.Preview = existing.Preview |
| 404 | next.ListingRevision = existing.ListingRevision |
| 405 | next.ListingContentDigest = existing.ListingContentDigest |
| 406 | } |
| 407 | |
| 408 | func EnsureBranchMeta(sessionPath string) (BranchMeta, error) { |
| 409 | var out BranchMeta |
| 410 | err := UpdateBranchMeta(sessionPath, false, func(m *BranchMeta) error { |
| 411 | out = *m |
| 412 | return nil |
| 413 | }) |
| 414 | return out, err |
| 415 | } |
| 416 | |
| 417 | // EnsureBranchMetaLocked is for callers that already hold LockSessionMetaPath. |
| 418 | func EnsureBranchMetaLocked(sessionPath string) (BranchMeta, error) { |
| 419 | return ensureBranchMetaUnlocked(sessionPath) |
| 420 | } |
| 421 | |
| 422 | func ensureBranchMetaUnlocked(sessionPath string) (BranchMeta, error) { |
| 423 | if sessionPath == "" { |
| 424 | return BranchMeta{}, fmt.Errorf("empty session path") |
| 425 | } |
| 426 | if m, ok, err := LoadBranchMeta(sessionPath); err != nil || ok { |
| 427 | return m, err |
| 428 | } |
| 429 | when := time.Now().UTC() |
| 430 | if info, err := os.Stat(sessionPath); err == nil { |
| 431 | when = info.ModTime().UTC() |
| 432 | } |
| 433 | m := BranchMeta{ |
| 434 | ID: BranchID(sessionPath), |
| 435 | CreatedAt: when, |
| 436 | UpdatedAt: when, |
| 437 | } |
| 438 | return m, saveBranchMeta(sessionPath, m, false) |
| 439 | } |
| 440 | |
| 441 | func TouchBranchMeta(sessionPath string) error { |
| 442 | return UpdateBranchMeta(sessionPath, false, func(m *BranchMeta) error { |
| 443 | m.UpdatedAt = time.Now().UTC() |
| 444 | return nil |
| 445 | }) |
| 446 | } |
| 447 | |
| 448 | func MarkSessionInFlightTurn(sessionPath string, startMessageIndex int, preserveUser bool) error { |
| 449 | _, err := BeginSessionInFlightTurn(sessionPath, startMessageIndex, preserveUser) |
| 450 | return err |
| 451 | } |
| 452 | |
| 453 | var inFlightTurnSequence atomic.Uint64 |
| 454 | |
| 455 | // BeginSessionInFlightTurn writes a new marker and returns the exact marker so |
| 456 | // the owner can later clear only this turn. The baseline fields are learned from |
| 457 | // the branch sidecar before replacing its marker. |
| 458 | func BeginSessionInFlightTurn(sessionPath string, startMessageIndex int, preserveUser bool) (InFlightTurnMeta, error) { |
| 459 | if sessionPath == "" { |
| 460 | return InFlightTurnMeta{}, fmt.Errorf("empty session path") |
| 461 | } |
| 462 | // Read the baseline and install the marker under the same in-process save |
| 463 | // lock. Otherwise an autosave can advance the revision between the read and |
| 464 | // SetSessionInFlightTurn, leaving the marker bound to a stale baseline. |
| 465 | unlock, err := LockSessionMetaPath(sessionPath) |
| 466 | if err != nil { |
| 467 | return InFlightTurnMeta{}, err |
| 468 | } |
| 469 | defer unlock() |
| 470 | meta, err := ensureBranchMetaUnlocked(sessionPath) |
| 471 | if err != nil { |
| 472 | return InFlightTurnMeta{}, err |
| 473 | } |
| 474 | marker := InFlightTurnMeta{ |
| 475 | ID: fmt.Sprintf("%s-%d-%d", SessionWriterID(), time.Now().UnixNano(), inFlightTurnSequence.Add(1)), |
| 476 | StartMessageIndex: startMessageIndex, |
| 477 | PreserveUser: preserveUser, |
| 478 | StartedAt: time.Now().UTC(), |
| 479 | } |
| 480 | marker.StartRevision = meta.Revision |
| 481 | marker.StartDigest = strings.TrimSpace(meta.ContentDigest) |
| 482 | marker.StartMessageIndex = max(marker.StartMessageIndex, 0) |
| 483 | meta.InFlightTurn = &marker |
| 484 | if err := saveBranchMeta(sessionPath, meta, false); err != nil { |
| 485 | return InFlightTurnMeta{}, err |
| 486 | } |
| 487 | return marker, nil |
| 488 | } |
| 489 | |
| 490 | // SetSessionInFlightTurn writes an existing in-flight marker verbatim. It is |
| 491 | // used when a running turn moves to a recovery branch: preserving StartedAt is |
| 492 | // what lets crash recovery relocate the turn after an in-turn compaction has |
| 493 | // rewritten its original message index. |
| 494 | func SetSessionInFlightTurn(sessionPath string, marker InFlightTurnMeta) error { |
| 495 | startMessageIndex := max(marker.StartMessageIndex, 0) |
| 496 | // The sidecar is read-modify-write; the per-path save lock keeps concurrent |
| 497 | // writers (autosave's UpdateSessionMeta, listing backfill) from dropping |
| 498 | // each other's fields. |
| 499 | unlock, err := LockSessionMetaPath(sessionPath) |
| 500 | if err != nil { |
| 501 | return err |
| 502 | } |
| 503 | defer unlock() |
| 504 | m, err := ensureBranchMetaUnlocked(sessionPath) |
| 505 | if err != nil { |
| 506 | return err |
| 507 | } |
| 508 | marker.StartMessageIndex = startMessageIndex |
| 509 | if marker.StartedAt.IsZero() { |
| 510 | marker.StartedAt = time.Now().UTC() |
| 511 | } |
| 512 | m.InFlightTurn = &marker |
| 513 | return saveBranchMeta(sessionPath, m, false) |
| 514 | } |
| 515 | |
| 516 | func ClearSessionInFlightTurn(sessionPath string) error { |
| 517 | _, err := ClearSessionInFlightTurnIfMatch(sessionPath, InFlightTurnMeta{}) |
| 518 | return err |
| 519 | } |
| 520 | |
| 521 | // ClearSessionInFlightTurnIfMatch clears a marker only when it still matches |
| 522 | // expected. A non-empty ID is authoritative; legacy markers without IDs fall |
| 523 | // back to the complete persisted marker shape for compatibility. |
| 524 | func ClearSessionInFlightTurnIfMatch(sessionPath string, expected InFlightTurnMeta) (bool, error) { |
| 525 | unlock, err := LockSessionMetaPath(sessionPath) |
| 526 | if err != nil { |
| 527 | return false, err |
| 528 | } |
| 529 | defer unlock() |
| 530 | m, ok, err := LoadBranchMeta(sessionPath) |
| 531 | if err != nil || !ok { |
| 532 | return false, err |
| 533 | } |
| 534 | if m.InFlightTurn == nil { |
| 535 | return false, nil |
| 536 | } |
| 537 | if expected.ID != "" { |
| 538 | if m.InFlightTurn.ID != expected.ID { |
| 539 | return false, nil |
| 540 | } |
| 541 | } else if expected.StartMessageIndex != 0 || expected.PreserveUser || !expected.StartedAt.IsZero() || expected.StartRevision != 0 || expected.StartDigest != "" { |
| 542 | if !sameInFlightTurn(*m.InFlightTurn, expected) { |
| 543 | return false, nil |
| 544 | } |
| 545 | } |
| 546 | m.InFlightTurn = nil |
| 547 | return true, saveBranchMeta(sessionPath, m, false) |
| 548 | } |
| 549 | |
| 550 | // PrepareSessionInFlightTurnCommit binds the owned marker to the exact final |
| 551 | // transcript before that transcript is saved. Recovery can then distinguish a |
| 552 | // crash after the save from a crash during the turn without guessing from roles |
| 553 | // or array indexes. |
| 554 | func PrepareSessionInFlightTurnCommit(sessionPath string, expected InFlightTurnMeta, digest string) (InFlightTurnMeta, bool, error) { |
| 555 | digest = strings.TrimSpace(digest) |
| 556 | if sessionPath == "" || expected.ID == "" || digest == "" { |
| 557 | return InFlightTurnMeta{}, false, nil |
| 558 | } |
| 559 | unlock, err := LockSessionMetaPath(sessionPath) |
| 560 | if err != nil { |
| 561 | return InFlightTurnMeta{}, false, err |
| 562 | } |
| 563 | defer unlock() |
| 564 | m, ok, err := LoadBranchMeta(sessionPath) |
| 565 | if err != nil || !ok || m.InFlightTurn == nil { |
| 566 | return InFlightTurnMeta{}, false, err |
| 567 | } |
| 568 | if m.InFlightTurn.ID != expected.ID { |
| 569 | return InFlightTurnMeta{}, false, nil |
| 570 | } |
| 571 | updated := *m.InFlightTurn |
| 572 | updated.CommitDigest = digest |
| 573 | m.InFlightTurn = &updated |
| 574 | if err := saveBranchMeta(sessionPath, m, false); err != nil { |
| 575 | return InFlightTurnMeta{}, false, err |
| 576 | } |
| 577 | return updated, true, nil |
| 578 | } |
| 579 | |
| 580 | func sameInFlightTurn(a, b InFlightTurnMeta) bool { |
| 581 | return a.ID == b.ID && |
| 582 | a.StartMessageIndex == b.StartMessageIndex && |
| 583 | a.PreserveUser == b.PreserveUser && |
| 584 | a.StartedAt.Equal(b.StartedAt) && |
| 585 | a.StartRevision == b.StartRevision && |
| 586 | a.StartDigest == b.StartDigest && |
| 587 | a.CommitDigest == b.CommitDigest |
| 588 | } |
| 589 | |
| 590 | func ListBranches(dir string) ([]BranchInfo, error) { |
| 591 | entries, err := os.ReadDir(dir) |
| 592 | if err != nil { |
| 593 | if os.IsNotExist(err) { |
| 594 | return nil, nil |
| 595 | } |
| 596 | return nil, err |
| 597 | } |
| 598 | var out []BranchInfo |
| 599 | for _, e := range entries { |
| 600 | if e.IsDir() || !store.IsSessionTranscriptName(e.Name()) { |
| 601 | continue |
| 602 | } |
| 603 | info, err := e.Info() |
| 604 | if err != nil { |
| 605 | continue |
| 606 | } |
| 607 | path := filepath.Join(dir, e.Name()) |
| 608 | if !IsVisibleSession(path) { |
| 609 | continue |
| 610 | } |
| 611 | preview, turns := previewSession(path) |
| 612 | if turns == 0 { |
| 613 | continue |
| 614 | } |
| 615 | meta, ok, err := LoadBranchMeta(path) |
| 616 | if err != nil { |
| 617 | continue |
| 618 | } |
| 619 | if !ok { |
| 620 | meta = BranchMeta{ |
| 621 | ID: BranchID(path), |
| 622 | CreatedAt: info.ModTime().UTC(), |
| 623 | UpdatedAt: info.ModTime().UTC(), |
| 624 | } |
| 625 | } |
| 626 | if meta.ID == "" { |
| 627 | meta.ID = BranchID(path) |
| 628 | } |
| 629 | out = append(out, BranchInfo{ |
| 630 | BranchMeta: meta, |
| 631 | Path: path, |
| 632 | ModTime: info.ModTime(), |
| 633 | Preview: preview, |
| 634 | Turns: turns, |
| 635 | }) |
| 636 | } |
| 637 | sort.Slice(out, func(i, j int) bool { |
| 638 | if out[i].CreatedAt.Equal(out[j].CreatedAt) { |
| 639 | return out[i].ID < out[j].ID |
| 640 | } |
| 641 | return out[i].CreatedAt.Before(out[j].CreatedAt) |
| 642 | }) |
| 643 | return out, nil |
| 644 | } |
| 645 | |
| 646 | // RenameSession updates the user-chosen display title in the session's |
| 647 | // .jsonl.meta sidecar file. If no meta file exists yet, one is created. The |
| 648 | // topic title remains a separate grouping label, so explicit session names do |
| 649 | // not fight topic auto-titling. |
| 650 | func RenameSession(sessionPath string, title string) error { |
| 651 | _, err := renameSession(sessionPath, "", false, title) |
| 652 | return err |
| 653 | } |
| 654 | |
| 655 | // SessionTitleSnapshot returns the title and an opaque mutation revision from |
| 656 | // one locked BranchMeta generation. Missing revisions are initialized before |
| 657 | // returning, upgrading old sidecars without changing their title. |
| 658 | func SessionTitleSnapshot(sessionPath string) (title, revision string, err error) { |
| 659 | if sessionPath == "" { |
| 660 | return "", "", fmt.Errorf("empty session path") |
| 661 | } |
| 662 | unlock, err := LockSessionMetaPath(sessionPath) |
| 663 | if err != nil { |
| 664 | return "", "", err |
| 665 | } |
| 666 | defer unlock() |
| 667 | m, err := ensureBranchMetaUnlocked(sessionPath) |
| 668 | if err != nil { |
| 669 | return "", "", err |
| 670 | } |
| 671 | if strings.TrimSpace(m.TitleRevision) == "" { |
| 672 | m.TitleRevision, err = newTitleRevision() |
| 673 | if err != nil { |
| 674 | return "", "", err |
| 675 | } |
| 676 | if err = saveBranchMetaTitle(sessionPath, m); err != nil { |
| 677 | return "", "", err |
| 678 | } |
| 679 | } |
| 680 | return m.CustomTitle, m.TitleRevision, nil |
| 681 | } |
| 682 | |
| 683 | // RenameSessionIfTitleRevision atomically updates a title only when the opaque |
| 684 | // title mutation identity still matches. This detects A→B→A and same-value |
| 685 | // manual saves, unlike a text-only comparison. |
| 686 | func RenameSessionIfTitleRevision(sessionPath, expectedRevision, title string) error { |
| 687 | _, err := renameSession(sessionPath, expectedRevision, true, title) |
| 688 | return err |
| 689 | } |
| 690 | |
| 691 | func renameSession(sessionPath, expectedRevision string, conditional bool, title string) (string, error) { |
| 692 | if sessionPath == "" { |
| 693 | return "", fmt.Errorf("empty session path") |
| 694 | } |
| 695 | // Read-modify-write on the sidecar: hold the per-path meta lock so a |
| 696 | // concurrent save (recordSessionContentRevision) can't have its Revision |
| 697 | // bump clobbered by a stale read-back here. |
| 698 | unlock, err := LockSessionMetaPath(sessionPath) |
| 699 | if err != nil { |
| 700 | return "", err |
| 701 | } |
| 702 | defer unlock() |
| 703 | m, err := ensureBranchMetaUnlocked(sessionPath) |
| 704 | if err != nil { |
| 705 | return "", err |
| 706 | } |
| 707 | if conditional && m.TitleRevision != expectedRevision { |
| 708 | return "", fmt.Errorf("%w: title revision changed", ErrSessionTitleChanged) |
| 709 | } |
| 710 | m.CustomTitle = strings.TrimSpace(title) |
| 711 | m.TitleRevision, err = newTitleRevision() |
| 712 | if err != nil { |
| 713 | return "", err |
| 714 | } |
| 715 | if err := saveBranchMetaTitle(sessionPath, m); err != nil { |
| 716 | return "", err |
| 717 | } |
| 718 | return m.TitleRevision, nil |
| 719 | } |
| 720 | |
| 721 | func newTitleRevision() (string, error) { |
| 722 | var value [16]byte |
| 723 | if _, err := rand.Read(value[:]); err != nil { |
| 724 | return "", fmt.Errorf("generate title revision: %w", err) |
| 725 | } |
| 726 | return hex.EncodeToString(value[:]), nil |
| 727 | } |
| 728 | |
| 729 | // LoadSessionModel reads the canonical provider/model ref saved beside a |
| 730 | // session transcript. |
| 731 | func LoadSessionModel(sessionPath string) (string, bool) { |
| 732 | model, _, ok := LoadSessionModelSelection(sessionPath) |
| 733 | return model, ok |
| 734 | } |
| 735 | |
| 736 | // LoadSessionModelSelection reads model and identity from the same sidecar |
| 737 | // generation. Missing identity denotes a legacy, unacknowledged selection. |
| 738 | func LoadSessionModelSelection(sessionPath string) (string, string, bool) { |
| 739 | meta, ok, err := LoadBranchMeta(sessionPath) |
| 740 | if err != nil || !ok { |
| 741 | return "", "", false |
| 742 | } |
| 743 | model := strings.TrimSpace(meta.Model) |
| 744 | if model == "" { |
| 745 | return "", "", false |
| 746 | } |
| 747 | return model, meta.ModelIdentity, true |
| 748 | } |
| 749 | |
| 750 | // SetBranchModelPreserveUpdated stores the canonical provider/model ref without |
| 751 | // changing the session activity timestamp. |
| 752 | func SetBranchModelPreserveUpdated(sessionPath, model string) error { |
| 753 | return setBranchModelSelection(sessionPath, model, nil) |
| 754 | } |
| 755 | |
| 756 | // SetBranchModelSelectionPreserveUpdated atomically acknowledges the selected |
| 757 | // connection without changing the session's activity timestamp. |
| 758 | func SetBranchModelSelectionPreserveUpdated(sessionPath, model, identity string) error { |
| 759 | return setBranchModelSelection(sessionPath, model, &identity) |
| 760 | } |
| 761 | |
| 762 | func setBranchModelSelection(sessionPath, model string, identity *string) error { |
| 763 | if sessionPath == "" { |
| 764 | return fmt.Errorf("empty session path") |
| 765 | } |
| 766 | unlock, err := LockSessionMetaPath(sessionPath) |
| 767 | if err != nil { |
| 768 | return err |
| 769 | } |
| 770 | defer unlock() |
| 771 | meta, err := ensureBranchMetaUnlocked(sessionPath) |
| 772 | if err != nil { |
| 773 | return err |
| 774 | } |
| 775 | setMetaModelSelection(&meta, model, identity) |
| 776 | return saveBranchMeta(sessionPath, meta, false) |
| 777 | } |
| 778 | |
| 779 | func setMetaModelSelection(meta *BranchMeta, model string, identity *string) { |
| 780 | model = strings.TrimSpace(model) |
| 781 | if meta.Model != model { |
| 782 | meta.ModelIdentity = "" |
| 783 | } |
| 784 | meta.Model = model |
| 785 | if identity != nil { |
| 786 | meta.ModelIdentity = *identity |
| 787 | } |
| 788 | } |
| 789 | |
| 790 | // UpdateSessionMeta refreshes the listing-only sidecar fields (model, preview, |
| 791 | // user-turn count) the sidebar and pickers read without decoding the .jsonl. |
| 792 | // markActivity bumps UpdatedAt (the autosave path passes true on a real turn); |
| 793 | // false preserves it (used to backfill legacy sessions during a read). An empty |
| 794 | // model leaves the stored model untouched. |
| 795 | func UpdateSessionMeta(sessionPath, model, preview string, turns int, markActivity bool) error { |
| 796 | if sessionPath == "" { |
| 797 | return fmt.Errorf("empty session path") |
| 798 | } |
| 799 | unlock, err := LockSessionMetaPath(sessionPath) |
| 800 | if err != nil { |
| 801 | return err |
| 802 | } |
| 803 | defer unlock() |
| 804 | m, err := ensureBranchMetaUnlocked(sessionPath) |
| 805 | if err != nil { |
| 806 | return err |
| 807 | } |
| 808 | if strings.TrimSpace(model) != "" { |
| 809 | setMetaModelSelection(&m, model, nil) |
| 810 | } |
| 811 | m.Preview = preview |
| 812 | m.Turns = turns |
| 813 | // These counts were derived from the current content, so mark them |
| 814 | // authoritative — listing can then trust Turns (even 0) without re-decoding. |
| 815 | m.SchemaVersion = BranchMetaCountsVersion |
| 816 | stampSessionListingProjection(&m) |
| 817 | return saveBranchMeta(sessionPath, m, markActivity) |
| 818 | } |
| 819 |