| 1 | package agent |
| 2 | |
| 3 | import ( |
| 4 | "context" |
| 5 | "crypto/sha256" |
| 6 | "errors" |
| 7 | "fmt" |
| 8 | "os" |
| 9 | "strings" |
| 10 | |
| 11 | "reasonix/internal/store" |
| 12 | ) |
| 13 | |
| 14 | type SessionListingRepairStatus string |
| 15 | |
| 16 | const ( |
| 17 | SessionListingRepairApplied SessionListingRepairStatus = "applied" |
| 18 | SessionListingRepairAlreadyCurrent SessionListingRepairStatus = "already_current" |
| 19 | SessionListingRepairSourceChanged SessionListingRepairStatus = "source_changed" |
| 20 | SessionListingRepairDamaged SessionListingRepairStatus = "damaged" |
| 21 | SessionListingRepairUnsupported SessionListingRepairStatus = "unsupported" |
| 22 | ) |
| 23 | |
| 24 | var ErrSessionListingRepairBusy = errors.New("session listing repair source is busy") |
| 25 | |
| 26 | // SessionListingRepairResult describes one convergent repair attempt. Preview |
| 27 | // and Turns are safe to publish only for applied/already_current results. |
| 28 | type SessionListingRepairResult struct { |
| 29 | Status SessionListingRepairStatus |
| 30 | Preview string |
| 31 | Turns int |
| 32 | LedgerRepaired bool |
| 33 | ContentFingerprint string |
| 34 | MetaFingerprint string |
| 35 | } |
| 36 | |
| 37 | // SessionListingGeneration identifies the transcript/event-log generation and |
| 38 | // its metadata sidecar while all writer locks for the session remain held. |
| 39 | type SessionListingGeneration struct { |
| 40 | ContentFingerprint string |
| 41 | MetaFingerprint string |
| 42 | } |
| 43 | |
| 44 | // TryLockSessionListingGeneration fences catalog publication against a |
| 45 | // foreground writer. The caller must invoke the returned unlock function. |
| 46 | func TryLockSessionListingGeneration(path string) (SessionListingGeneration, func(), error) { |
| 47 | path = strings.TrimSpace(path) |
| 48 | if path == "" { |
| 49 | return SessionListingGeneration{}, nil, fmt.Errorf("empty session path") |
| 50 | } |
| 51 | unlock, err := lockSessionListingRepair(path) |
| 52 | if err != nil { |
| 53 | return SessionListingGeneration{}, nil, err |
| 54 | } |
| 55 | return SessionListingGeneration{ |
| 56 | ContentFingerprint: sessionListingCatalogContentFingerprint(path), |
| 57 | MetaFingerprint: sessionListingCatalogFileFingerprint(BranchMetaPath(path)), |
| 58 | }, unlock, nil |
| 59 | } |
| 60 | |
| 61 | // RepairSessionListingProjection repairs one session generation while holding |
| 62 | // only that session's save/file/meta locks. Foreground saves win immediately; |
| 63 | // callers persist a retry instead of waiting behind active work. |
| 64 | func RepairSessionListingProjection(ctx context.Context, path string) (result SessionListingRepairResult, resultErr error) { |
| 65 | path = strings.TrimSpace(path) |
| 66 | if path == "" { |
| 67 | return SessionListingRepairResult{}, fmt.Errorf("empty session path") |
| 68 | } |
| 69 | if err := ctx.Err(); err != nil { |
| 70 | return SessionListingRepairResult{}, err |
| 71 | } |
| 72 | unlock, err := lockSessionListingRepair(path) |
| 73 | if err != nil { |
| 74 | return SessionListingRepairResult{}, err |
| 75 | } |
| 76 | defer unlock() |
| 77 | defer func() { |
| 78 | result.ContentFingerprint = sessionListingCatalogContentFingerprint(path) |
| 79 | result.MetaFingerprint = sessionListingCatalogFileFingerprint(BranchMetaPath(path)) |
| 80 | }() |
| 81 | meta, metaOK, err := LoadBranchMeta(path) |
| 82 | if err != nil { |
| 83 | if isDamagedSessionRepairError(err) { |
| 84 | return SessionListingRepairResult{Status: SessionListingRepairDamaged}, nil |
| 85 | } |
| 86 | return SessionListingRepairResult{}, err |
| 87 | } |
| 88 | if !metaOK { |
| 89 | meta = BranchMeta{ID: BranchID(path)} |
| 90 | } |
| 91 | if !sessionHeadIndexStale(path) { |
| 92 | if result, handled, err := repairSessionListingFromIndex(path, meta); handled || err != nil { |
| 93 | return result, err |
| 94 | } |
| 95 | } |
| 96 | return repairSessionListingFromReplay(ctx, path, meta) |
| 97 | } |
| 98 | |
| 99 | func lockSessionListingRepair(path string) (func(), error) { |
| 100 | unlockSave, ok := tryLockSessionSavePath(path) |
| 101 | if !ok { |
| 102 | return nil, ErrSessionListingRepairBusy |
| 103 | } |
| 104 | unlockFile, err := tryLockSessionFile(path) |
| 105 | if err != nil { |
| 106 | unlockSave() |
| 107 | if errors.Is(err, ErrSessionFileLockHeld) { |
| 108 | return nil, ErrSessionListingRepairBusy |
| 109 | } |
| 110 | return nil, err |
| 111 | } |
| 112 | unlockMeta, ok, err := tryLockSessionMetaPath(path) |
| 113 | if err != nil { |
| 114 | unlockFile() |
| 115 | unlockSave() |
| 116 | return nil, err |
| 117 | } |
| 118 | if !ok { |
| 119 | unlockFile() |
| 120 | unlockSave() |
| 121 | return nil, ErrSessionListingRepairBusy |
| 122 | } |
| 123 | return func() { unlockMeta(); unlockFile(); unlockSave() }, nil |
| 124 | } |
| 125 | |
| 126 | func repairSessionListingFromIndex(path string, meta BranchMeta) (SessionListingRepairResult, bool, error) { |
| 127 | preview, turns, ok, unsupported, err := indexedSessionListing(path, meta) |
| 128 | if err != nil { |
| 129 | return SessionListingRepairResult{}, true, err |
| 130 | } |
| 131 | if unsupported { |
| 132 | return SessionListingRepairResult{Status: SessionListingRepairUnsupported}, true, nil |
| 133 | } |
| 134 | if !ok { |
| 135 | return SessionListingRepairResult{}, false, nil |
| 136 | } |
| 137 | if sessionListingProjectionFresh(meta.SchemaVersion, meta.Turns, meta.Revision, |
| 138 | meta.ListingRevision, meta.ContentDigest, meta.ListingContentDigest) && |
| 139 | meta.Preview == preview && meta.Turns == turns { |
| 140 | return SessionListingRepairResult{Status: SessionListingRepairAlreadyCurrent, Preview: preview, Turns: turns}, true, nil |
| 141 | } |
| 142 | meta.Preview, meta.Turns, meta.SchemaVersion = preview, turns, BranchMetaCountsVersion |
| 143 | stampSessionListingProjection(&meta) |
| 144 | if err := saveBranchMeta(path, meta, false); err != nil { |
| 145 | return SessionListingRepairResult{}, true, err |
| 146 | } |
| 147 | return SessionListingRepairResult{Status: SessionListingRepairApplied, Preview: preview, Turns: turns}, true, nil |
| 148 | } |
| 149 | |
| 150 | func repairSessionListingFromReplay(ctx context.Context, path string, meta BranchMeta) (SessionListingRepairResult, error) { |
| 151 | before, err := sessionRepairContentFingerprint(path) |
| 152 | if err != nil { |
| 153 | return SessionListingRepairResult{}, err |
| 154 | } |
| 155 | msgs, state, repairable, err := loadSessionDisplayMessagesContextUnlocked(ctx, path) |
| 156 | if err != nil { |
| 157 | if ctxErr := ctx.Err(); ctxErr != nil { |
| 158 | return SessionListingRepairResult{}, ctxErr |
| 159 | } |
| 160 | if isUnsupportedSessionRepairError(err) { |
| 161 | return SessionListingRepairResult{Status: SessionListingRepairUnsupported}, nil |
| 162 | } |
| 163 | if isDamagedSessionRepairError(err) { |
| 164 | return SessionListingRepairResult{Status: SessionListingRepairDamaged}, nil |
| 165 | } |
| 166 | return SessionListingRepairResult{}, err |
| 167 | } |
| 168 | if !repairable { |
| 169 | return SessionListingRepairResult{Status: SessionListingRepairDamaged}, nil |
| 170 | } |
| 171 | if err := ctx.Err(); err != nil { |
| 172 | return SessionListingRepairResult{}, err |
| 173 | } |
| 174 | after, err := sessionRepairContentFingerprint(path) |
| 175 | if err != nil { |
| 176 | return SessionListingRepairResult{}, err |
| 177 | } |
| 178 | if before != after { |
| 179 | return SessionListingRepairResult{Status: SessionListingRepairSourceChanged}, nil |
| 180 | } |
| 181 | |
| 182 | preview, turns := SessionPreviewFromMessages(msgs) |
| 183 | ledgerCurrent := meta.Revision > 0 && strings.TrimSpace(meta.ContentDigest) == state.DigestHex |
| 184 | if meta.Recovered && strings.TrimSpace(meta.RecoveryDigest) != state.DigestHex { |
| 185 | ledgerCurrent = false |
| 186 | } |
| 187 | ledgerRepaired := !ledgerCurrent |
| 188 | if ledgerRepaired { |
| 189 | meta.Revision = max(int64(1), meta.Revision+1) |
| 190 | meta.ContentDigest = state.DigestHex |
| 191 | if meta.Recovered || strings.TrimSpace(meta.RecoveryDigest) != "" { |
| 192 | meta.RecoveryDigest = state.DigestHex |
| 193 | } |
| 194 | meta.WriterID = SessionWriterID() |
| 195 | } |
| 196 | meta.Preview = preview |
| 197 | meta.Turns = turns |
| 198 | meta.SchemaVersion = BranchMetaCountsVersion |
| 199 | stampSessionListingProjection(&meta) |
| 200 | |
| 201 | // The display index ranges describe the compatibility JSONL exactly, so |
| 202 | // refresh it from this single authoritative replay before publishing meta. |
| 203 | if err := writeSessionMessagesContext(ctx, path, msgs); err != nil { |
| 204 | return SessionListingRepairResult{}, fmt.Errorf("write session display read model: %w", err) |
| 205 | } |
| 206 | if err := refreshSessionEventIndexContext(ctx, path, msgs, state.Digest, meta.Revision); err != nil { |
| 207 | return SessionListingRepairResult{}, err |
| 208 | } |
| 209 | idx, err := BuildSessionDisplayIndexContext(ctx, msgs, meta.Revision, true, state.Digest) |
| 210 | if err != nil { |
| 211 | return SessionListingRepairResult{}, fmt.Errorf("encode session display index: %w", err) |
| 212 | } |
| 213 | if err := WriteSessionDisplayIndexContext(ctx, store.SessionDisplayIndex(path), idx); err != nil { |
| 214 | return SessionListingRepairResult{}, err |
| 215 | } |
| 216 | if err := saveBranchMetaContext(ctx, path, meta, false); err != nil { |
| 217 | return SessionListingRepairResult{}, err |
| 218 | } |
| 219 | return SessionListingRepairResult{ |
| 220 | Status: SessionListingRepairApplied, Preview: preview, Turns: turns, LedgerRepaired: ledgerRepaired, |
| 221 | }, nil |
| 222 | } |
| 223 | |
| 224 | func indexedSessionListing(path string, meta BranchMeta) (preview string, turns int, ok, unsupported bool, err error) { |
| 225 | digest := strings.TrimSpace(meta.ContentDigest) |
| 226 | if meta.Revision <= 0 || digest == "" || meta.Recovered && strings.TrimSpace(meta.RecoveryDigest) != digest { |
| 227 | return "", 0, false, false, nil |
| 228 | } |
| 229 | idx, err := LoadSessionDisplayIndex(store.SessionDisplayIndex(path)) |
| 230 | if err != nil || idx == nil || !idx.ListingPreviewKnown || !idx.RevisionKnown || |
| 231 | idx.Revision != meta.Revision || idx.ContentDigest != digest { |
| 232 | return "", 0, false, false, nil |
| 233 | } |
| 234 | info, err := os.Stat(path) |
| 235 | if err != nil { |
| 236 | return "", 0, false, false, err |
| 237 | } |
| 238 | if info.IsDir() || info.Size() != idx.TranscriptSize { |
| 239 | return "", 0, false, false, nil |
| 240 | } |
| 241 | indexInfo, err := os.Stat(store.SessionDisplayIndex(path)) |
| 242 | if err != nil || !indexInfo.ModTime().After(SessionContentModTime(path)) { |
| 243 | return "", 0, false, false, nil |
| 244 | } |
| 245 | probe, err := probeSessionEventLog(path) |
| 246 | if err != nil { |
| 247 | return "", 0, false, false, err |
| 248 | } |
| 249 | if probe.futureSchema { |
| 250 | return "", 0, false, true, nil |
| 251 | } |
| 252 | if probe.native && probe.size > 0 { |
| 253 | eventIdx, err := readSessionEventIndex(path) |
| 254 | if err != nil || eventIdx == nil || eventIdx.LogSize != probe.size || |
| 255 | eventIdx.Revision != meta.Revision || eventIdx.ContentDigest != digest || |
| 256 | eventIdx.MessageCount != idx.MessageCount { |
| 257 | return "", 0, false, false, nil |
| 258 | } |
| 259 | eventInfo, eventErr := os.Stat(store.SessionEventIndex(path)) |
| 260 | logInfo, logErr := os.Stat(store.SessionEventLog(path)) |
| 261 | if eventErr != nil || logErr != nil || !eventInfo.ModTime().After(logInfo.ModTime()) { |
| 262 | return "", 0, false, false, nil |
| 263 | } |
| 264 | } |
| 265 | return idx.ListingPreview, idx.AuthoredTurns, true, false, nil |
| 266 | } |
| 267 | |
| 268 | func sessionRepairContentFingerprint(path string) (string, error) { |
| 269 | h := sha256.New() |
| 270 | for _, artifact := range []string{path, store.SessionEventLog(path)} { |
| 271 | info, err := os.Stat(artifact) |
| 272 | if err != nil { |
| 273 | if os.IsNotExist(err) { |
| 274 | _, _ = fmt.Fprintf(h, "missing\x00") |
| 275 | continue |
| 276 | } |
| 277 | return "", err |
| 278 | } |
| 279 | _, _ = fmt.Fprintf(h, "%d\x00%d\x00%d\x00", info.Size(), info.ModTime().UnixNano(), info.Mode()) |
| 280 | } |
| 281 | return fmt.Sprintf("%x", h.Sum(nil)), nil |
| 282 | } |
| 283 | |
| 284 | func sessionListingCatalogFileFingerprint(path string) string { |
| 285 | info, err := os.Stat(path) |
| 286 | if err != nil { |
| 287 | return "" |
| 288 | } |
| 289 | return fmt.Sprintf("%d:%d", info.Size(), info.ModTime().UnixNano()) |
| 290 | } |
| 291 | |
| 292 | func sessionListingCatalogContentFingerprint(path string) string { |
| 293 | return sessionListingCatalogFileFingerprint(path) + "|" + sessionListingCatalogFileFingerprint(store.SessionEventLog(path)) |
| 294 | } |
| 295 | |
| 296 | func isUnsupportedSessionRepairError(err error) bool { |
| 297 | return errors.Is(err, ErrSessionReplayLimitExceeded) || |
| 298 | strings.Contains(err.Error(), "unsupported schema") || |
| 299 | strings.Contains(err.Error(), "supports up to") || |
| 300 | strings.Contains(err.Error(), "unsupported event type") |
| 301 | } |
| 302 | |
| 303 | func isDamagedSessionRepairError(err error) bool { |
| 304 | text := err.Error() |
| 305 | return strings.Contains(text, "decode session transcript") || |
| 306 | strings.Contains(text, "decode session event log") || |
| 307 | strings.Contains(text, "decode ") |
| 308 | } |
| 309 |