Implement restore planning for the restore subcommand

internal/app/restore.go

@@ -13,6 +13,7 @@ import (
 
 var newObjectStoreFromConfigFn = storage.NewObjectStoreFromConfig
 var discoverRemoteCurrentStateFn = discoverRemoteCurrentState
+var buildRestorePlanFn = buildRestorePlan
 
 // Restore validates restore CLI/config inputs and storage preflight for future restore phases.
 func Restore(ctx context.Context, args []string, out io.Writer) error {
@@ -74,13 +75,32 @@ func Restore(ctx context.Context, args []string, out io.Writer) error {
 	if err != nil {
 		return fmt.Errorf("restore: %w", err)
 	}
-
+	plan, err := buildRestorePlanFn(ctx, cfg, current, objectStore, RestorePlanOptions{
-	// Phase 3 boundary: discovery is implemented; planning/execution is deferred.
+		IncludeAudio: includeAudio,
-	_ = dryRun
+		Force:        force,
-	_ = force
+		DryRun:       dryRun,
-	_ = includeAudio
+	})
+	if err != nil {
+		return fmt.Errorf("restore: %w", err)
+	}
+	if err := writeRestorePlan(out, current, plan, RestorePlanOptions{
+		IncludeAudio: includeAudio,
+		Force:        force,
+		DryRun:       dryRun,
+	}); err != nil {
+		return fmt.Errorf("restore: write plan output: %w", err)
+	}
+	if dryRun {
+		return nil
+	}
+	if plan.ConflictCount > 0 && !force {
+		return fmt.Errorf(
+			"restore: plan has %d conflicting path(s); rerun with --force or resolve local conflicts",
+			plan.ConflictCount,
+		)
+	}
 	return fmt.Errorf(
-		"restore: discovered remote current state for %s/%s (run %s); not yet implemented (phase 3: remote current-state discovery)",
+		"restore: planned remote restore for %s/%s (run %s); not yet implemented (phase 4: restore execution)",
 		current.Campaign,
 		current.SessionID,
 		current.RunID,

internal/app/restore_plan.go

@@ -0,0 +1,344 @@
+package app
+
+import (
+	"context"
+	"fmt"
+	"io"
+	"os"
+	"path"
+	"path/filepath"
+	"sort"
+	"strings"
+
+	"gitea.maximumdirect.net/eric/narratio/internal/adapters/storage"
+	"gitea.maximumdirect.net/eric/narratio/internal/artifacts"
+	"gitea.maximumdirect.net/eric/narratio/internal/config"
+)
+
+// RestoreActionKind identifies one restore planner action.
+type RestoreActionKind string
+
+const (
+	RestoreActionDownload RestoreActionKind = "download"
+	RestoreActionSkipSame RestoreActionKind = "skip_same"
+	RestoreActionConflict RestoreActionKind = "conflict"
+)
+
+// RestoreAction is one deterministic planner action.
+type RestoreAction struct {
+	Kind              RestoreActionKind
+	RemoteKey         string
+	LocalRelativePath string
+	LocalPath         string
+	Size              int64
+	ETag              string
+	ExistsLocal       bool
+	SameLocal         bool
+	Conflict          bool
+	Reason            string
+}
+
+// RestorePlan is the deterministic output of restore planning.
+type RestorePlan struct {
+	Actions       []RestoreAction
+	DownloadCount int
+	SkipSameCount int
+	ConflictCount int
+}
+
+// RestorePlanOptions control restore planning scope and classification.
+type RestorePlanOptions struct {
+	IncludeAudio bool
+	Force        bool
+	DryRun       bool
+}
+
+func buildRestorePlan(ctx context.Context, cfg *config.Config, current *RemoteCurrentState, store storage.ObjectStore, opts RestorePlanOptions) (*RestorePlan, error) {
+	if cfg == nil || cfg.Pipeline == nil || cfg.Session == nil {
+		return nil, fmt.Errorf("resolved config with pipeline/session is required")
+	}
+	if current == nil {
+		return nil, fmt.Errorf("remote current state is required")
+	}
+	if store == nil {
+		return nil, fmt.Errorf("remote object store is required")
+	}
+	prefix := normalizeRemoteKey(current.SessionPrefix)
+	if strings.TrimSpace(prefix) == "" {
+		return nil, fmt.Errorf("remote session prefix is required")
+	}
+	if !strings.HasSuffix(prefix, "/") {
+		prefix += "/"
+	}
+
+	sessionPaths := artifacts.NewLocalStore(cfg.Pipeline.Workspace.Root).SessionPathsFor(cfg.Session.Campaign, cfg.Session.SessionID)
+	objects, err := store.List(ctx, prefix)
+	if err != nil {
+		return nil, fmt.Errorf("list remote session objects under %q: %w", prefix, err)
+	}
+
+	candidates := make(map[string]storage.ObjectInfo, len(objects)+1)
+	for _, obj := range objects {
+		key := normalizeRemoteKey(obj.Key)
+		if key == "" {
+			continue
+		}
+		obj.Key = key
+		candidates[key] = obj
+	}
+	if strings.TrimSpace(current.CurrentManifestKey) != "" {
+		key := normalizeRemoteKey(current.CurrentManifestKey)
+		if _, ok := candidates[key]; !ok {
+			candidates[key] = storage.ObjectInfo{Key: key}
+		}
+	}
+
+	actions := make([]RestoreAction, 0, len(candidates))
+	for key, obj := range candidates {
+		rel, include, err := restoreLocalRelativePathForKey(prefix, normalizeRemoteKey(current.CurrentManifestKey), key, opts.IncludeAudio)
+		if err != nil {
+			return nil, fmt.Errorf("map remote key %q: %w", key, err)
+		}
+		if !include {
+			continue
+		}
+		localPath, err := joinWithinSessionRoot(sessionPaths.Root, rel)
+		if err != nil {
+			return nil, fmt.Errorf("map remote key %q: %w", key, err)
+		}
+
+		action, err := classifyRestoreAction(ctx, store, obj, rel, localPath, opts.Force)
+		if err != nil {
+			return nil, fmt.Errorf("classify remote key %q: %w", key, err)
+		}
+		actions = append(actions, action)
+	}
+
+	sort.Slice(actions, func(i, j int) bool {
+		if actions[i].LocalRelativePath == actions[j].LocalRelativePath {
+			return actions[i].RemoteKey < actions[j].RemoteKey
+		}
+		return actions[i].LocalRelativePath < actions[j].LocalRelativePath
+	})
+
+	plan := &RestorePlan{Actions: actions}
+	for _, action := range actions {
+		switch action.Kind {
+		case RestoreActionDownload:
+			plan.DownloadCount++
+		case RestoreActionSkipSame:
+			plan.SkipSameCount++
+		case RestoreActionConflict:
+			plan.ConflictCount++
+		}
+	}
+
+	_ = opts.DryRun
+	return plan, nil
+}
+
+func normalizeRemoteKey(v string) string {
+	return strings.Trim(strings.ReplaceAll(strings.TrimSpace(v), "\\", "/"), "/")
+}
+
+func restoreLocalRelativePathForKey(sessionPrefix, currentManifestKey, key string, includeAudio bool) (string, bool, error) {
+	if key == "" {
+		return "", false, nil
+	}
+	if key == currentManifestKey {
+		return config.PathManifestFile, true, nil
+	}
+	if !strings.HasPrefix(key, sessionPrefix) {
+		return "", false, fmt.Errorf("key is outside resolved session prefix %q", sessionPrefix)
+	}
+
+	rel := strings.TrimPrefix(key, sessionPrefix)
+	rel = strings.TrimSpace(rel)
+	if rel == "" {
+		return "", false, nil
+	}
+
+	cleanRel := path.Clean(rel)
+	if cleanRel == "." || cleanRel == "" {
+		return "", false, nil
+	}
+	if cleanRel == ".." || strings.HasPrefix(cleanRel, "../") || strings.HasPrefix(cleanRel, "/") {
+		return "", false, fmt.Errorf("key relative path %q escapes session scope", rel)
+	}
+
+	if cleanRel == config.PathManifestFile {
+		return config.PathManifestFile, true, nil
+	}
+	if strings.HasPrefix(cleanRel, config.S3CurrentSegment+"/") {
+		return "", false, nil
+	}
+	if strings.HasPrefix(cleanRel, config.S3RunsSegment+"/") {
+		return "", false, nil
+	}
+
+	excludedRoots := []string{
+		config.PathLogsDirSegment,
+		config.PathReportsDirSegment,
+		config.PathConfigDirSegment,
+		config.PathInputsDirSegment,
+	}
+	for _, root := range excludedRoots {
+		if cleanRel == root || strings.HasPrefix(cleanRel, root+"/") {
+			return "", false, nil
+		}
+	}
+
+	if cleanRel == config.PathTranscriptsSegment || strings.HasPrefix(cleanRel, config.PathTranscriptsSegment+"/") {
+		return cleanRel, true, nil
+	}
+	if cleanRel == config.PathArtifactsDirSegment || strings.HasPrefix(cleanRel, config.PathArtifactsDirSegment+"/") {
+		return cleanRel, true, nil
+	}
+	if includeAudio && (cleanRel == config.PathAudioDirSegment || strings.HasPrefix(cleanRel, config.PathAudioDirSegment+"/")) {
+		return cleanRel, true, nil
+	}
+
+	return "", false, nil
+}
+
+func joinWithinSessionRoot(sessionRoot, relative string) (string, error) {
+	if strings.TrimSpace(sessionRoot) == "" {
+		return "", fmt.Errorf("session root is required")
+	}
+	cleanRel := path.Clean(strings.TrimSpace(relative))
+	if cleanRel == "." || cleanRel == "" {
+		return "", fmt.Errorf("relative path is required")
+	}
+	if cleanRel == ".." || strings.HasPrefix(cleanRel, "../") || strings.HasPrefix(cleanRel, "/") {
+		return "", fmt.Errorf("relative path escapes session root")
+	}
+	abs := filepath.Clean(filepath.Join(sessionRoot, filepath.FromSlash(cleanRel)))
+	root := filepath.Clean(sessionRoot)
+	if abs != root && !strings.HasPrefix(abs, root+string(filepath.Separator)) {
+		return "", fmt.Errorf("resolved local path escapes session root")
+	}
+	return abs, nil
+}
+
+func classifyRestoreAction(
+	ctx context.Context,
+	store storage.ObjectStore,
+	object storage.ObjectInfo,
+	localRelPath string,
+	localPath string,
+	force bool,
+) (RestoreAction, error) {
+	action := RestoreAction{
+		RemoteKey:         normalizeRemoteKey(object.Key),
+		LocalRelativePath: localRelPath,
+		LocalPath:         localPath,
+		Size:              object.Size,
+		ETag:              object.ETag,
+	}
+
+	info, err := os.Stat(localPath)
+	if err != nil {
+		if os.IsNotExist(err) {
+			action.Kind = RestoreActionDownload
+			action.Reason = "local file missing"
+			return action, nil
+		}
+		return RestoreAction{}, fmt.Errorf("stat local file: %w", err)
+	}
+
+	action.ExistsLocal = true
+	if info.IsDir() {
+		action.Kind = RestoreActionConflict
+		action.Conflict = true
+		action.Reason = "local path is a directory"
+		return action, nil
+	}
+
+	if object.Size > 0 && info.Size() != object.Size {
+		if force {
+			action.Kind = RestoreActionDownload
+			action.Reason = "local file differs (size mismatch); overwrite with --force"
+			return action, nil
+		}
+		action.Kind = RestoreActionConflict
+		action.Conflict = true
+		action.Reason = "local file differs (size mismatch)"
+		return action, nil
+	}
+
+	localDigest, err := artifacts.SHA256File(localPath)
+	if err != nil {
+		return RestoreAction{}, fmt.Errorf("checksum local file: %w", err)
+	}
+	remotePath, err := downloadObjectToTemp(ctx, store, action.RemoteKey, "narratio-restore-plan-remote-*.tmp")
+	if err != nil {
+		return RestoreAction{}, fmt.Errorf("download remote object: %w", err)
+	}
+	defer func() { _ = os.Remove(remotePath) }()
+
+	remoteDigest, err := artifacts.SHA256File(remotePath)
+	if err != nil {
+		return RestoreAction{}, fmt.Errorf("checksum remote object: %w", err)
+	}
+
+	if remoteDigest == localDigest {
+		action.Kind = RestoreActionSkipSame
+		action.SameLocal = true
+		action.Reason = "local file matches remote content"
+		return action, nil
+	}
+
+	if force {
+		action.Kind = RestoreActionDownload
+		action.Reason = "local file differs; overwrite with --force"
+		return action, nil
+	}
+
+	action.Kind = RestoreActionConflict
+	action.Conflict = true
+	action.Reason = "local file differs"
+	return action, nil
+}
+
+func writeRestorePlan(out io.Writer, current *RemoteCurrentState, plan *RestorePlan, opts RestorePlanOptions) error {
+	if out == nil {
+		return fmt.Errorf("output writer is required")
+	}
+	if current == nil {
+		return fmt.Errorf("remote current state is required")
+	}
+	if plan == nil {
+		return fmt.Errorf("restore plan is required")
+	}
+
+	if _, err := fmt.Fprintf(
+		out,
+		"restore plan: session %s/%s run=%s actions=%d download=%d skip_same=%d conflict=%d dry_run=%t force=%t include_audio=%t\n",
+		current.Campaign,
+		current.SessionID,
+		current.RunID,
+		len(plan.Actions),
+		plan.DownloadCount,
+		plan.SkipSameCount,
+		plan.ConflictCount,
+		opts.DryRun,
+		opts.Force,
+		opts.IncludeAudio,
+	); err != nil {
+		return err
+	}
+	for _, action := range plan.Actions {
+		if _, err := fmt.Fprintf(out, "%s %s <- %s", action.Kind, action.LocalRelativePath, action.RemoteKey); err != nil {
+			return err
+		}
+		if strings.TrimSpace(action.Reason) != "" {
+			if _, err := fmt.Fprintf(out, " (%s)", action.Reason); err != nil {
+				return err
+			}
+		}
+		if _, err := fmt.Fprintln(out); err != nil {
+			return err
+		}
+	}
+	return nil
+}

internal/app/restore_plan_test.go

@@ -0,0 +1,199 @@
+package app
+
+import (
+	"context"
+	"path/filepath"
+	"reflect"
+	"strings"
+	"testing"
+
+	"gitea.maximumdirect.net/eric/narratio/internal/adapters/storage"
+	"gitea.maximumdirect.net/eric/narratio/internal/artifacts"
+	"gitea.maximumdirect.net/eric/narratio/internal/config"
+)
+
+func TestRestorePlanDefaultScope(t *testing.T) {
+	cfg := restorePlanConfig(t)
+	current := restorePlanCurrentState(t, cfg)
+	store := &storage.FakeBackend{}
+
+	seedRestoreObject(store, current.CurrentManifestKey, []byte(`{"session_id":"2026-05-03"}`))
+	seedRestoreObject(store, current.SessionPrefix+"transcripts/full.json", []byte(`{"segments":[1]}`))
+	seedRestoreObject(store, current.SessionPrefix+"artifacts/session_recap.md", []byte("# recap\n"))
+	seedRestoreObject(store, current.SessionPrefix+"audio/alice.flac", []byte("audio"))
+	seedRestoreObject(store, current.SessionPrefix+"runs/20260519T010203Z-a1b2/manifest.json", []byte("{}"))
+	seedRestoreObject(store, current.SessionPrefix+"logs/archive.log", []byte("log"))
+
+	plan, err := buildRestorePlan(context.Background(), cfg, current, store, RestorePlanOptions{})
+	if err != nil {
+		t.Fatalf("buildRestorePlan() error = %v", err)
+	}
+
+	got := actionRelPaths(plan.Actions)
+	want := []string{"artifacts/session_recap.md", "manifest.json", "transcripts/full.json"}
+	if !reflect.DeepEqual(got, want) {
+		t.Fatalf("action local paths = %#v, want %#v", got, want)
+	}
+	if plan.DownloadCount != 3 || plan.SkipSameCount != 0 || plan.ConflictCount != 0 {
+		t.Fatalf("counts = download=%d skip_same=%d conflict=%d, want 3/0/0", plan.DownloadCount, plan.SkipSameCount, plan.ConflictCount)
+	}
+}
+
+func TestRestorePlanIncludeAudio(t *testing.T) {
+	cfg := restorePlanConfig(t)
+	current := restorePlanCurrentState(t, cfg)
+	store := &storage.FakeBackend{}
+
+	seedRestoreObject(store, current.CurrentManifestKey, []byte(`{"session_id":"2026-05-03"}`))
+	seedRestoreObject(store, current.SessionPrefix+"audio/alice.flac", []byte("audio"))
+
+	plan, err := buildRestorePlan(context.Background(), cfg, current, store, RestorePlanOptions{IncludeAudio: true})
+	if err != nil {
+		t.Fatalf("buildRestorePlan() error = %v", err)
+	}
+	got := actionRelPaths(plan.Actions)
+	want := []string{"audio/alice.flac", "manifest.json"}
+	if !reflect.DeepEqual(got, want) {
+		t.Fatalf("action local paths = %#v, want %#v", got, want)
+	}
+}
+
+func TestRestorePlanClassifiesSameAndConflict(t *testing.T) {
+	cfg := restorePlanConfig(t)
+	current := restorePlanCurrentState(t, cfg)
+	store := &storage.FakeBackend{}
+
+	seedRestoreObject(store, current.CurrentManifestKey, []byte(`{"session_id":"2026-05-03"}`))
+	seedRestoreObject(store, current.SessionPrefix+"transcripts/full.json", []byte(`{"segments":[1]}`))
+	seedRestoreObject(store, current.SessionPrefix+"artifacts/session_recap.md", []byte("remote-content\n"))
+
+	sessionRoot := artifacts.SessionWorkDirForCampaign(cfg.Pipeline.Workspace.Root, cfg.Session.Campaign, cfg.Session.SessionID)
+	mustWriteTestFile(t, filepath.Join(sessionRoot, "transcripts", "full.json"), `{"segments":[1]}`)
+	mustWriteTestFile(t, filepath.Join(sessionRoot, "artifacts", "session_recap.md"), "different\n")
+
+	plan, err := buildRestorePlan(context.Background(), cfg, current, store, RestorePlanOptions{})
+	if err != nil {
+		t.Fatalf("buildRestorePlan() error = %v", err)
+	}
+
+	if plan.SkipSameCount != 1 {
+		t.Fatalf("SkipSameCount = %d, want 1", plan.SkipSameCount)
+	}
+	if plan.ConflictCount != 1 {
+		t.Fatalf("ConflictCount = %d, want 1", plan.ConflictCount)
+	}
+
+	actionByRel := map[string]RestoreAction{}
+	for _, action := range plan.Actions {
+		actionByRel[action.LocalRelativePath] = action
+	}
+	if actionByRel["transcripts/full.json"].Kind != RestoreActionSkipSame {
+		t.Fatalf("transcripts/full.json kind = %q, want %q", actionByRel["transcripts/full.json"].Kind, RestoreActionSkipSame)
+	}
+	if actionByRel["artifacts/session_recap.md"].Kind != RestoreActionConflict {
+		t.Fatalf("artifacts/session_recap.md kind = %q, want %q", actionByRel["artifacts/session_recap.md"].Kind, RestoreActionConflict)
+	}
+}
+
+func TestRestorePlanForceTurnsConflictsIntoDownloads(t *testing.T) {
+	cfg := restorePlanConfig(t)
+	current := restorePlanCurrentState(t, cfg)
+	store := &storage.FakeBackend{}
+
+	seedRestoreObject(store, current.CurrentManifestKey, []byte(`{"session_id":"2026-05-03"}`))
+	seedRestoreObject(store, current.SessionPrefix+"artifacts/session_recap.md", []byte("remote-content\n"))
+
+	sessionRoot := artifacts.SessionWorkDirForCampaign(cfg.Pipeline.Workspace.Root, cfg.Session.Campaign, cfg.Session.SessionID)
+	mustWriteTestFile(t, filepath.Join(sessionRoot, "artifacts", "session_recap.md"), "different\n")
+
+	plan, err := buildRestorePlan(context.Background(), cfg, current, store, RestorePlanOptions{Force: true})
+	if err != nil {
+		t.Fatalf("buildRestorePlan() error = %v", err)
+	}
+
+	actionByRel := map[string]RestoreAction{}
+	for _, action := range plan.Actions {
+		actionByRel[action.LocalRelativePath] = action
+	}
+	recap := actionByRel["artifacts/session_recap.md"]
+	if recap.Kind != RestoreActionDownload {
+		t.Fatalf("artifacts/session_recap.md kind = %q, want %q", recap.Kind, RestoreActionDownload)
+	}
+	if plan.ConflictCount != 0 {
+		t.Fatalf("ConflictCount = %d, want 0", plan.ConflictCount)
+	}
+}
+
+func TestRestorePlanTraversalUnsafeKeyFails(t *testing.T) {
+	cfg := restorePlanConfig(t)
+	current := restorePlanCurrentState(t, cfg)
+	store := &storage.FakeBackend{}
+
+	seedRestoreObject(store, current.CurrentManifestKey, []byte(`{"session_id":"2026-05-03"}`))
+	seedRestoreObject(store, current.SessionPrefix+"artifacts/../../escape.txt", []byte("bad"))
+
+	_, err := buildRestorePlan(context.Background(), cfg, current, store, RestorePlanOptions{})
+	if err == nil {
+		t.Fatal("expected error, got nil")
+	}
+	if !strings.Contains(err.Error(), "escapes session scope") {
+		t.Fatalf("error = %v, want traversal safety failure", err)
+	}
+}
+
+func seedRestoreObject(store *storage.FakeBackend, key string, data []byte) {
+	store.SeedObject(storage.FakeObject{Key: key, Data: data})
+}
+
+func actionRelPaths(actions []RestoreAction) []string {
+	out := make([]string, 0, len(actions))
+	for _, action := range actions {
+		out = append(out, action.LocalRelativePath)
+	}
+	return out
+}
+
+func restorePlanConfig(t *testing.T) *config.Config {
+	t.Helper()
+	workspaceRoot := t.TempDir()
+	return &config.Config{
+		Pipeline: &config.PipelineConfig{
+			Workspace: config.WorkspaceConfig{Root: workspaceRoot},
+		},
+		Session: &config.SessionConfig{
+			SessionID: "2026-05-03",
+			Campaign:  "sample-campaign",
+		},
+	}
+}
+
+func restorePlanCurrentState(t *testing.T, cfg *config.Config) *RemoteCurrentState {
+	t.Helper()
+	sessionPrefix := artifacts.S3SessionPrefix("dnd", cfg.Session.Campaign, cfg.Session.SessionID)
+	manifestKey, runIDKey := artifacts.ResolveArchiveCurrentStateKeys(sessionPrefix)
+	return &RemoteCurrentState{
+		Bucket:             "test-bucket",
+		SessionPrefix:      sessionPrefix,
+		CurrentManifestKey: manifestKey,
+		CurrentRunIDKey:    runIDKey,
+		RunID:              "20260519T010203Z-a1b2c3d4",
+		SessionID:          cfg.Session.SessionID,
+		Campaign:           cfg.Session.Campaign,
+	}
+}
+
+func TestWriteRestorePlan(t *testing.T) {
+	current := &RemoteCurrentState{Campaign: "sample-campaign", SessionID: "2026-05-03", RunID: "r-1"}
+	plan := &RestorePlan{Actions: []RestoreAction{{Kind: RestoreActionDownload, LocalRelativePath: "manifest.json", RemoteKey: "k", Reason: "local file missing"}}, DownloadCount: 1}
+	var out strings.Builder
+	if err := writeRestorePlan(&out, current, plan, RestorePlanOptions{DryRun: true}); err != nil {
+		t.Fatalf("writeRestorePlan() error = %v", err)
+	}
+	text := out.String()
+	if !strings.Contains(text, "restore plan: session sample-campaign/2026-05-03 run=r-1") {
+		t.Fatalf("output = %q, want plan summary", text)
+	}
+	if !strings.Contains(text, "download manifest.json <- k") {
+		t.Fatalf("output = %q, want action line", text)
+	}
+}

internal/app/restore_test.go

@@ -37,9 +37,11 @@ func TestExecuteRestoreHelp(t *testing.T) {
 func TestExecuteRestoreRecognizedAndReturnsNYI(t *testing.T) {
 	origStoreFn := newObjectStoreFromConfigFn
 	origDiscoverFn := discoverRemoteCurrentStateFn
+	origPlanFn := buildRestorePlanFn
 	t.Cleanup(func() {
 		newObjectStoreFromConfigFn = origStoreFn
 		discoverRemoteCurrentStateFn = origDiscoverFn
+		buildRestorePlanFn = origPlanFn
 	})
 	newObjectStoreFromConfigFn = func(context.Context, *config.Config) (storage.ObjectStore, error) {
 		return &storage.FakeBackend{}, nil
@@ -51,6 +53,19 @@ func TestExecuteRestoreRecognizedAndReturnsNYI(t *testing.T) {
 			RunID:     "20260519T010203Z-a1b2c3d4",
 		}, nil
 	}
+	buildRestorePlanFn = func(context.Context, *config.Config, *RemoteCurrentState, storage.ObjectStore, RestorePlanOptions) (*RestorePlan, error) {
+		return &RestorePlan{
+			Actions: []RestoreAction{
+				{
+					Kind:              RestoreActionDownload,
+					LocalRelativePath: "manifest.json",
+					RemoteKey:         "dnd/campaigns/sample-campaign/sessions/2026-05-03/current/manifest.json",
+					Reason:            "local file missing",
+				},
+			},
+			DownloadCount: 1,
+		}, nil
+	}
 
 	workspaceRoot := t.TempDir()
 	pipelinePath, sessionPath := writeValidConfigFiles(t, workspaceRoot)
@@ -70,23 +85,23 @@ func TestExecuteRestoreRecognizedAndReturnsNYI(t *testing.T) {
 		&stdout,
 		&stderr,
 	)
-	if code == 0 {
+	if code != 0 {
-		t.Fatal("exit code = 0, want non-zero (phase 3 NYI boundary)")
+		t.Fatalf("exit code = %d, want 0 for --dry-run restore planning; stderr=%q", code, stderr.String())
 	}
-	errText := stderr.String()
+	if stderr.Len() != 0 {
-	if !strings.Contains(errText, "discovered remote current state for sample-campaign/2026-05-03 (run 20260519T010203Z-a1b2c3d4)") {
+		t.Fatalf("stderr = %q, want empty", stderr.String())
-		t.Fatalf("stderr = %q, want discovery summary context", errText)
 	}
-	if !strings.Contains(errText, "not yet implemented (phase 3: remote current-state discovery)") {
+	outText := stdout.String()
-		t.Fatalf("stderr = %q, want phase-3 NYI marker", errText)
+	if !strings.Contains(outText, "restore plan: session sample-campaign/2026-05-03 run=20260519T010203Z-a1b2c3d4") {
+		t.Fatalf("stdout = %q, want restore plan summary", outText)
 	}
-	if strings.Contains(errText, "unknown command") {
+	if !strings.Contains(outText, "download manifest.json <- dnd/campaigns/sample-campaign/sessions/2026-05-03/current/manifest.json") {
-		t.Fatalf("stderr = %q, restore should be recognized command", errText)
+		t.Fatalf("stdout = %q, want action output", outText)
 	}
 
 	manifestPath := artifacts.SessionManifestPathForCampaign(workspaceRoot, "sample-campaign", "2026-05-03")
 	if _, err := os.Stat(manifestPath); !os.IsNotExist(err) {
-		t.Fatalf("manifest should not be created during phase-3 restore discovery; stat err=%v", err)
+		t.Fatalf("manifest should not be created during phase-4 restore planning; stat err=%v", err)
 	}
 }
 
@@ -155,6 +170,97 @@ func TestExecuteRestoreDiscoveryErrorSurfaced(t *testing.T) {
 	}
 }
 
+func TestExecuteRestoreNonDryRunConflictFailsBeforeNYI(t *testing.T) {
+	origStoreFn := newObjectStoreFromConfigFn
+	origDiscoverFn := discoverRemoteCurrentStateFn
+	origPlanFn := buildRestorePlanFn
+	t.Cleanup(func() {
+		newObjectStoreFromConfigFn = origStoreFn
+		discoverRemoteCurrentStateFn = origDiscoverFn
+		buildRestorePlanFn = origPlanFn
+	})
+	newObjectStoreFromConfigFn = func(context.Context, *config.Config) (storage.ObjectStore, error) {
+		return &storage.FakeBackend{}, nil
+	}
+	discoverRemoteCurrentStateFn = func(context.Context, *config.Config, storage.ObjectStore) (*RemoteCurrentState, error) {
+		return &RemoteCurrentState{
+			SessionID: "2026-05-03",
+			Campaign:  "sample-campaign",
+			RunID:     "20260519T010203Z-a1b2c3d4",
+		}, nil
+	}
+	buildRestorePlanFn = func(context.Context, *config.Config, *RemoteCurrentState, storage.ObjectStore, RestorePlanOptions) (*RestorePlan, error) {
+		return &RestorePlan{
+			Actions: []RestoreAction{
+				{Kind: RestoreActionConflict, LocalRelativePath: "transcripts/full.json", RemoteKey: "k", Reason: "local file differs"},
+			},
+			ConflictCount: 1,
+		}, nil
+	}
+
+	workspaceRoot := t.TempDir()
+	pipelinePath, sessionPath := writeValidConfigFiles(t, workspaceRoot)
+	var stdout bytes.Buffer
+	var stderr bytes.Buffer
+	code := Execute([]string{"restore", "--config", pipelinePath, "--session", sessionPath}, &stdout, &stderr)
+	if code == 0 {
+		t.Fatal("exit code = 0, want non-zero")
+	}
+	if !strings.Contains(stdout.String(), "restore plan: session sample-campaign/2026-05-03 run=20260519T010203Z-a1b2c3d4") {
+		t.Fatalf("stdout = %q, want plan output", stdout.String())
+	}
+	if !strings.Contains(stderr.String(), "plan has 1 conflicting path(s)") {
+		t.Fatalf("stderr = %q, want conflict failure", stderr.String())
+	}
+	if strings.Contains(stderr.String(), "phase 4: restore execution") {
+		t.Fatalf("stderr = %q, should fail before phase-4 NYI boundary", stderr.String())
+	}
+}
+
+func TestExecuteRestoreNonDryRunForceStillStopsAtNYI(t *testing.T) {
+	origStoreFn := newObjectStoreFromConfigFn
+	origDiscoverFn := discoverRemoteCurrentStateFn
+	origPlanFn := buildRestorePlanFn
+	t.Cleanup(func() {
+		newObjectStoreFromConfigFn = origStoreFn
+		discoverRemoteCurrentStateFn = origDiscoverFn
+		buildRestorePlanFn = origPlanFn
+	})
+	newObjectStoreFromConfigFn = func(context.Context, *config.Config) (storage.ObjectStore, error) {
+		return &storage.FakeBackend{}, nil
+	}
+	discoverRemoteCurrentStateFn = func(context.Context, *config.Config, storage.ObjectStore) (*RemoteCurrentState, error) {
+		return &RemoteCurrentState{
+			SessionID: "2026-05-03",
+			Campaign:  "sample-campaign",
+			RunID:     "20260519T010203Z-a1b2c3d4",
+		}, nil
+	}
+	buildRestorePlanFn = func(context.Context, *config.Config, *RemoteCurrentState, storage.ObjectStore, RestorePlanOptions) (*RestorePlan, error) {
+		return &RestorePlan{
+			Actions: []RestoreAction{
+				{Kind: RestoreActionDownload, LocalRelativePath: "transcripts/full.json", RemoteKey: "k", Reason: "local file differs; overwrite with --force"},
+			},
+			DownloadCount: 1,
+		}, nil
+	}
+
+	workspaceRoot := t.TempDir()
+	pipelinePath, sessionPath := writeValidConfigFiles(t, workspaceRoot)
+	var stdout bytes.Buffer
+	var stderr bytes.Buffer
+	code := Execute([]string{"restore", "--config", pipelinePath, "--session", sessionPath, "--force"}, &stdout, &stderr)
+	if code == 0 {
+		t.Fatal("exit code = 0, want non-zero at phase-4 execution boundary")
+	}
+	if !strings.Contains(stdout.String(), "restore plan: session sample-campaign/2026-05-03 run=20260519T010203Z-a1b2c3d4") {
+		t.Fatalf("stdout = %q, want plan output", stdout.String())
+	}
+	if !strings.Contains(stderr.String(), "not yet implemented (phase 4: restore execution)") {
+		t.Fatalf("stderr = %q, want phase-4 NYI marker", stderr.String())
+	}
+}
+
 func writeRestoreConfigWithoutStorage(t *testing.T, workspaceRoot string) (string, string) {
 	t.Helper()