Resolve canonical previous-session artifact sources from prepared previous cache

internal/artifacts/artifact_resolver.go

@@ -18,6 +18,9 @@ const (
 	ArtifactTranscriptFull     = "narratio.transcript.full"
 	ArtifactTranscriptTrimmed  = "narratio.transcript.trimmed"
 	ArtifactBoundsSession      = "narratio.bounds.session"
+
+	ArtifactProvenancePreviousCacheManifestInput = "manifest.inputs.previous_cache"
+	ArtifactProvenancePreviousCacheFilesystem    = "current_session.previous_cache"
 )
 
 // ErrSessionArtifactNotFound is returned when no readable artifact exists for a known ID.
@@ -186,6 +189,9 @@ func ResolveSessionArtifact(paths SessionPaths, m *manifest.Manifest, source str
 // configured narratio.artifact.<name> sources through runtime catalog availability.
 func ResolveSessionArtifactWithCatalog(paths SessionPaths, m *manifest.Manifest, source string, catalog *ArtifactCatalog) (ResolvedSessionArtifact, error) {
 	normalized := strings.TrimSpace(source)
+	if IsPreviousSessionArtifactSource(normalized) {
+		return ResolvePreviousSessionArtifactWithCatalog(paths, m, normalized, catalog)
+	}
 	if !IsConfiguredArtifactSource(normalized) {
 		return ResolveSessionArtifact(paths, m, normalized)
 	}
@@ -211,6 +217,72 @@ func ResolveSessionArtifactWithCatalog(paths SessionPaths, m *manifest.Manifest,
 	}, nil
 }
 
+// ResolvePreviousSessionArtifactWithCatalog resolves one canonical previous-session source id
+// to the prepared current-session previous-cache path.
+func ResolvePreviousSessionArtifactWithCatalog(
+	paths SessionPaths,
+	m *manifest.Manifest,
+	source string,
+	catalog *ArtifactCatalog,
+) (ResolvedSessionArtifact, error) {
+	artifactName, ok := PreviousSessionArtifactName(source)
+	if !ok {
+		return ResolvedSessionArtifact{}, fmt.Errorf("unsupported previous-session artifact source %q", source)
+	}
+	if catalog == nil {
+		return ResolvedSessionArtifact{}, fmt.Errorf("previous-session artifact source %q requires runtime artifact catalog", source)
+	}
+
+	configuredSourceID := ConfiguredArtifactSourceID(artifactName)
+	entry, ok := catalog.Lookup(configuredSourceID)
+	if !ok {
+		return ResolvedSessionArtifact{}, fmt.Errorf("unsupported previous-session artifact source %q", source)
+	}
+	candidates := previousSessionCacheCandidatePaths(paths, entry.CanonicalRelPath)
+	if len(candidates) == 0 {
+		return ResolvedSessionArtifact{}, &SessionArtifactNotFoundError{ArtifactID: source}
+	}
+
+	manifestInputPaths := manifestInputPathSet(paths, m)
+	fallback := ""
+	for _, candidate := range candidates {
+		exists, isDir, statErr := pathExists(candidate)
+		if statErr != nil {
+			return ResolvedSessionArtifact{}, fmt.Errorf("stat %q: %w", candidate, statErr)
+		}
+		if !exists || isDir {
+			continue
+		}
+		if err := validateResolvedContent(candidate, contentText); err != nil {
+			return ResolvedSessionArtifact{}, fmt.Errorf("validate %q: %w", source, err)
+		}
+		if _, ok := manifestInputPaths[candidate]; ok {
+			return ResolvedSessionArtifact{
+				ID:            source,
+				Path:          candidate,
+				ProducerStage: "prepare",
+				OutputKind:    "previous_session_artifact",
+				Provenance:    ArtifactProvenancePreviousCacheManifestInput,
+			}, nil
+		}
+		if fallback == "" {
+			fallback = candidate
+		}
+	}
+
+	if fallback != "" {
+		return ResolvedSessionArtifact{
+			ID:            source,
+			Path:          fallback,
+			ProducerStage: "prepare",
+			OutputKind:    "previous_session_artifact",
+			Provenance:    ArtifactProvenancePreviousCacheFilesystem,
+		}, nil
+	}
+
+	return ResolvedSessionArtifact{}, &SessionArtifactNotFoundError{ArtifactID: source}
+}
+
 func manifestArtifactCandidates(paths SessionPaths, m *manifest.Manifest, spec artifactSpec) []ResolvedSessionArtifact {
 	if m == nil || len(m.Stages) == 0 || spec.ProducerStage == "" || spec.OutputKind == "" {
 		return nil
@@ -259,6 +331,50 @@ func dedupeResolvedArtifacts(values []ResolvedSessionArtifact) []ResolvedSession
 	return out
 }
 
+func previousSessionCacheCandidatePaths(paths SessionPaths, canonicalRelPath string) []string {
+	trimmed := strings.TrimSpace(canonicalRelPath)
+	if trimmed == "" {
+		return nil
+	}
+	normalized := filepath.ToSlash(filepath.Clean(filepath.FromSlash(trimmed)))
+	if normalized == "." || normalized == "" || normalized == ".." || strings.HasPrefix(normalized, "../") || strings.HasPrefix(normalized, "/") {
+		return nil
+	}
+
+	relCandidates := []string{normalized}
+	const artifactsPrefix = "artifacts/"
+	if strings.HasPrefix(normalized, artifactsPrefix) && len(normalized) > len(artifactsPrefix) {
+		relCandidates = append(relCandidates, strings.TrimPrefix(normalized, artifactsPrefix))
+	}
+
+	out := make([]string, 0, len(relCandidates))
+	seen := map[string]struct{}{}
+	for _, rel := range relCandidates {
+		abs := filepath.Clean(SessionPreviousArtifactPath(paths, rel))
+		if _, ok := seen[abs]; ok {
+			continue
+		}
+		seen[abs] = struct{}{}
+		out = append(out, abs)
+	}
+	return out
+}
+
+func manifestInputPathSet(paths SessionPaths, m *manifest.Manifest) map[string]struct{} {
+	if m == nil || len(m.Inputs) == 0 {
+		return nil
+	}
+	out := make(map[string]struct{}, len(m.Inputs))
+	for _, in := range m.Inputs {
+		resolved := filepath.Clean(ResolveSessionLocalPathForRead(paths, in.Path))
+		if strings.TrimSpace(resolved) == "" {
+			continue
+		}
+		out[resolved] = struct{}{}
+	}
+	return out
+}
+
 func pathExists(path string) (exists bool, isDir bool, err error) {
 	info, err := os.Stat(path)
 	if err == nil {

internal/artifacts/artifact_resolver_test.go

@@ -318,3 +318,120 @@ func TestResolveSessionArtifactWithCatalogUnsupportedConfiguredSourceFails(t *te
 		t.Fatalf("error = %q, want unsupported artifact source", err.Error())
 	}
 }
+
+func TestResolvePreviousSessionArtifactWithCatalogPrefersManifestInputRecord(t *testing.T) {
+	workspace := t.TempDir()
+	paths := buildSessionPaths(workspace, "campaign", "session")
+
+	manifestBackedPath := SessionPreviousArtifactPath(paths, "artifacts/session_recap.md")
+	fallbackPath := SessionPreviousArtifactPath(paths, "session_recap.md")
+	if err := os.MkdirAll(filepath.Dir(manifestBackedPath), 0o755); err != nil {
+		t.Fatalf("MkdirAll() error = %v", err)
+	}
+	if err := os.MkdirAll(filepath.Dir(fallbackPath), 0o755); err != nil {
+		t.Fatalf("MkdirAll() error = %v", err)
+	}
+	if err := os.WriteFile(manifestBackedPath, []byte("recap from manifest input\n"), 0o644); err != nil {
+		t.Fatalf("WriteFile() error = %v", err)
+	}
+	if err := os.WriteFile(fallbackPath, []byte("recap fallback\n"), 0o644); err != nil {
+		t.Fatalf("WriteFile() error = %v", err)
+	}
+
+	catalog := NewArtifactCatalog()
+	if err := catalog.RegisterConfiguredArtifacts(
+		map[string]ConfiguredArtifactDefinition{
+			"session_recap": {Enabled: true, OutputPath: "artifacts/session_recap.md"},
+		},
+		nil,
+	); err != nil {
+		t.Fatalf("RegisterConfiguredArtifacts() error = %v", err)
+	}
+
+	m := manifest.New("session", time.Now().UTC())
+	m.Inputs = []manifest.InputRecord{
+		{Kind: "previous_artifact", Path: manifestBackedPath},
+	}
+
+	resolved, err := ResolvePreviousSessionArtifactWithCatalog(
+		paths,
+		m,
+		"narratio.previous_session.artifact.session_recap",
+		catalog,
+	)
+	if err != nil {
+		t.Fatalf("ResolvePreviousSessionArtifactWithCatalog() error = %v", err)
+	}
+	if resolved.Path != manifestBackedPath {
+		t.Fatalf("resolved path = %q, want %q", resolved.Path, manifestBackedPath)
+	}
+	if resolved.Provenance != ArtifactProvenancePreviousCacheManifestInput {
+		t.Fatalf("provenance = %q, want %q", resolved.Provenance, ArtifactProvenancePreviousCacheManifestInput)
+	}
+}
+
+func TestResolvePreviousSessionArtifactWithCatalogFallsBackToPreparedCachePath(t *testing.T) {
+	workspace := t.TempDir()
+	paths := buildSessionPaths(workspace, "campaign", "session")
+
+	fallbackPath := SessionPreviousArtifactPath(paths, "session_recap.md")
+	if err := os.MkdirAll(filepath.Dir(fallbackPath), 0o755); err != nil {
+		t.Fatalf("MkdirAll() error = %v", err)
+	}
+	if err := os.WriteFile(fallbackPath, []byte("recap fallback\n"), 0o644); err != nil {
+		t.Fatalf("WriteFile() error = %v", err)
+	}
+
+	catalog := NewArtifactCatalog()
+	if err := catalog.RegisterConfiguredArtifacts(
+		map[string]ConfiguredArtifactDefinition{
+			"session_recap": {Enabled: true, OutputPath: "artifacts/session_recap.md"},
+		},
+		nil,
+	); err != nil {
+		t.Fatalf("RegisterConfiguredArtifacts() error = %v", err)
+	}
+
+	resolved, err := ResolvePreviousSessionArtifactWithCatalog(
+		paths,
+		nil,
+		"narratio.previous_session.artifact.session_recap",
+		catalog,
+	)
+	if err != nil {
+		t.Fatalf("ResolvePreviousSessionArtifactWithCatalog() error = %v", err)
+	}
+	if resolved.Path != fallbackPath {
+		t.Fatalf("resolved path = %q, want %q", resolved.Path, fallbackPath)
+	}
+	if resolved.Provenance != ArtifactProvenancePreviousCacheFilesystem {
+		t.Fatalf("provenance = %q, want %q", resolved.Provenance, ArtifactProvenancePreviousCacheFilesystem)
+	}
+}
+
+func TestResolvePreviousSessionArtifactWithCatalogMissingReturnsTypedError(t *testing.T) {
+	workspace := t.TempDir()
+	paths := buildSessionPaths(workspace, "campaign", "session")
+	catalog := NewArtifactCatalog()
+	if err := catalog.RegisterConfiguredArtifacts(
+		map[string]ConfiguredArtifactDefinition{
+			"session_recap": {Enabled: true, OutputPath: "artifacts/session_recap.md"},
+		},
+		nil,
+	); err != nil {
+		t.Fatalf("RegisterConfiguredArtifacts() error = %v", err)
+	}
+
+	_, err := ResolvePreviousSessionArtifactWithCatalog(
+		paths,
+		nil,
+		"narratio.previous_session.artifact.session_recap",
+		catalog,
+	)
+	if err == nil {
+		t.Fatal("expected error, got nil")
+	}
+	if !errors.Is(err, ErrSessionArtifactNotFound) {
+		t.Fatalf("errors.Is(err, ErrSessionArtifactNotFound)=false; err=%v", err)
+	}
+}

internal/stage/analyze.go

@@ -632,13 +632,21 @@ func resolveScriptoriumInput(
 ) (string, bool, *artifacts.ResolvedSessionArtifact, error) {
 	source := strings.TrimSpace(inputCfg.Source)
 	if artifacts.IsPreviousSessionArtifactSource(source) {
-		if inputCfg.Required {
-			return "", false, nil, fmt.Errorf(
-				"required previous-session input source %q is unavailable; run narratio run-stage --force prepare",
-				source,
-			)
+		resolved, err := artifacts.ResolvePreviousSessionArtifactWithCatalog(paths, m, source, runtimeCatalog)
+		if err == nil {
+			copy := resolved
+			return resolved.Path, true, &copy, nil
 		}
-		return "", false, nil, nil
+		if errors.Is(err, artifacts.ErrSessionArtifactNotFound) {
+			if inputCfg.Required {
+				return "", false, nil, fmt.Errorf(
+					"required previous-session input source %q is unavailable; run narratio run-stage --force prepare",
+					source,
+				)
+			}
+			return "", false, nil, nil
+		}
+		return "", false, nil, err
 	}
 	switch source {
 	case "previous_session_artifact":

internal/stage/analyze_test.go

@@ -736,6 +736,61 @@ func TestAnalyzeRequiredPreviousSessionArtifactInputGuidesPrepareForce(t *testin
 	}
 }
 
+func TestAnalyzeResolvesCanonicalPreviousSessionArtifactFromManifestInput(t *testing.T) {
+	env, m, fake := setupAnalyzeEnv(t)
+	paths := sessionPathsForEnv(env, m.SessionID)
+	writeAnalyzeFile(t, filepath.Join(paths.TranscriptsDir, "trimmed.json"), `{"segments":[]}`)
+
+	previousPath := artifacts.SessionPreviousArtifactPath(paths, "artifacts/session_recap.md")
+	writeAnalyzeFile(t, previousPath, "previous recap\n")
+	m.Inputs = append(m.Inputs, manifest.InputRecord{
+		Kind: "previous_artifact",
+		Path: previousPath,
+	})
+
+	sessionRecap := env.Config.Pipeline.Scriptorium.Artifacts["session_recap"]
+	sessionRecap.Inputs["previous_recap"] = config.ScriptoriumInputConfig{
+		Source:   "narratio.previous_session.artifact.session_recap",
+		Required: true,
+	}
+	env.Config.Pipeline.Scriptorium.Artifacts["session_recap"] = sessionRecap
+
+	_, err := (analyzeStage{}).Run(context.Background(), env, m)
+	if err != nil {
+		t.Fatalf("Run() error = %v", err)
+	}
+	if len(fake.RunRequests) != 1 {
+		t.Fatalf("run requests = %d, want 1", len(fake.RunRequests))
+	}
+	if got := fake.RunRequests[0].InputPaths["previous_recap"]; got != previousPath {
+		t.Fatalf("previous_recap input = %q, want %q", got, previousPath)
+	}
+}
+
+func TestAnalyzeOmitsOptionalMissingCanonicalPreviousSessionArtifact(t *testing.T) {
+	env, m, fake := setupAnalyzeEnv(t)
+	paths := sessionPathsForEnv(env, m.SessionID)
+	writeAnalyzeFile(t, filepath.Join(paths.TranscriptsDir, "trimmed.json"), `{"segments":[]}`)
+
+	sessionRecap := env.Config.Pipeline.Scriptorium.Artifacts["session_recap"]
+	sessionRecap.Inputs["previous_recap"] = config.ScriptoriumInputConfig{
+		Source:   "narratio.previous_session.artifact.session_recap",
+		Required: false,
+	}
+	env.Config.Pipeline.Scriptorium.Artifacts["session_recap"] = sessionRecap
+
+	_, err := (analyzeStage{}).Run(context.Background(), env, m)
+	if err != nil {
+		t.Fatalf("Run() error = %v", err)
+	}
+	if len(fake.RunRequests) != 1 {
+		t.Fatalf("run requests = %d, want 1", len(fake.RunRequests))
+	}
+	if _, exists := fake.RunRequests[0].InputPaths["previous_recap"]; exists {
+		t.Fatalf("optional canonical previous_recap should be omitted when unavailable")
+	}
+}
+
 func TestAnalyzeFailsWhenOutputPathMissing(t *testing.T) {
 	env, m, fake := setupAnalyzeEnv(t)
 	paths := sessionPathsForEnv(env, m.SessionID)