feat(podcasts): schema, RLS policy extension, sqlc queries — feed core foundations

Podcast integration task 1.1 (plan: podcast-integration.md §6/§8, D20).

WHY: podcasts are a new first-class media domain — RSS feeds users
subscribe to personally, with episodes as media_items rows so progress,
stats and the audio player work unchanged. Visibility is per-user
(strict: only your subscriptions), which after the RLS migration
(2026-10-29) belongs in the POLICIES, not Go helpers.

Schema (idempotent — schema.sql re-executes every boot):
- 'podcasts' library type seeded (ON CONFLICT DO NOTHING, ARRAY[]::TEXT[]
  cast required — bare ARRAY[] 42802s under ON_ERROR_STOP)
- podcast_feeds: per-library feed entity (UNIQUE(library_id, feed_url)),
  full RSS/iTunes/Podcasting-2.0 metadata inventory, conditional-GET
  validators, is_complete poll backoff
- podcast_subscriptions: the ONLY user-writable podcast state (display
  name, auto-download policy); deliberately UNGOVERNED — it IS the read
  policy's lookup table
- media_items episode columns: source/source_feed_id/episode_guid/
  feed_position/season/episode/enclosure_url/declared_duration/
  transcript_url/chapters_url/hosts/guests + download state machine
  (pending|queued|downloading|downloaded|failed + error + attempts),
  all partial-indexed so scan rows never touch them
- libraries.allow_member_feeds (first per-library knob); library_folders
  .purpose ('podcast' download roots, scanner-skipped)

RLS (inside the labeled policy block):
- p_media_items_visible gains the podcast-episode subscription predicate
  + admin escape (source IS DISTINCT FROM 'podcast_episode' guard keeps
  scan rows on the cheap path); unset identity still fails loud
- podcast_feeds governed identically: library-visibility join AND
  subscriber-or-admin SELECT; permissive write stand-ins (mandatory at
  ENABLE time; fetcher/worker declare first-admin, add-feed upsert uses
  ON CONFLICT DO UPDATE RETURNING so creators never need SELECT on
  foreign rows)
- Verified against dev DB: migration identity sees nothing, admin sees
  all, member sees feeds/episodes only post-subscribe (probed in a
  rolled-back tx — no rows persisted)

sqlc: 30 new queries (feed upsert/CRUD, subscriptions, episode
upsert-with-write-after-success-guard, download state transitions,
poller worklist, subscription-scoped search) — no visibility clauses
anywhere, per the D20 scoping model.

internal/database/querier.go

@@ -53,11 +53,17 @@ type Querier interface {
 	// collections page); same live filter as GetCollectionItems, plus the
 	// future-hybrid excluded exclusion and an optional library scope.
 	CountCollectionLiveItems(ctx context.Context, arg CountCollectionLiveItemsParams) (int32, error)
+	CountDownloadedEpisodes(ctx context.Context, sourceFeedID pgtype.UUID) (int64, error)
 	// Sibling-book count for sidecar naming (MetadataWriter): a dir-scoped
 	// metadata.opf may only be written when NO other non-archived item
 	// shares the directory; otherwise the sidecar goes to
 	// <basename>.opf so one book's metadata can never poison dir-mates.
 	CountOtherMediaItemsInDir(ctx context.Context, arg CountOtherMediaItemsInDirParams) (int32, error)
+	CountPodcastFeedSubscribers(ctx context.Context, feedID pgtype.UUID) (int64, error)
+	// Sidebar/page gate (D13): >=1 podcasts-type library the user can see
+	// (COALESCE(is_visible,true) semantics — mirrors GetUserVisibleLibraries).
+	CountPodcastLibrariesForUser(ctx context.Context, userID pgtype.UUID) (int64, error)
+	CountUndownloadedEpisodes(ctx context.Context, sourceFeedID pgtype.UUID) (int64, error)
 	// Count unlinked books for a device (ignored rows stay hidden)
 	CountUnlinkedBooks(ctx context.Context, deviceID pgtype.UUID) (int64, error)
 	// Banner count: unresolved, non-ignored queue rows across the caller's own
@@ -116,6 +122,22 @@ type Querier interface {
 	// ============================================
 	CreateOrUpdateKoboEntitlement(ctx context.Context, arg CreateOrUpdateKoboEntitlementParams) (KoboEntitlements, error)
 	// ============================================================================
+	// PODCASTS / RSS FEEDS (plan ~/.opencode/plan/podcast-integration.md §6/§8)
+	// Visibility is RLS-enforced (schema policy block) — NO query here carries
+	// visibility clauses. Feed reads run under the acting user's identity
+	// (subscriber-or-admin policy); the fetcher/worker run as first-admin.
+	// The fetcher/download worker is the SOLE writer of feed/episode metadata;
+	// users write only podcast_subscriptions rows.
+	// ============================================================================
+	// Add-feed upsert keyed on the per-library UNIQUE(library_id, feed_url):
+	// a second subscriber adding the same URL attaches to the existing row
+	// instead of erroring. DO UPDATE (not DO NOTHING) so the RETURNING works
+	// even when the conflicting row is invisible to the actor under RLS
+	// (non-admin creators cannot SELECT other users' feeds). Metadata columns
+	// are filled by the fetcher right after; this only establishes identity.
+	CreatePodcastFeed(ctx context.Context, arg CreatePodcastFeedParams) (PodcastFeeds, error)
+	CreatePodcastLibraryFolder(ctx context.Context, arg CreatePodcastLibraryFolderParams) (LibraryFolders, error)
+	// ============================================================================
 	// PROCESSING ISSUES QUERIES
 	// ============================================================================
 	// Widened upsert (faceted plan Phase 11): media_item_id and file_path
@@ -160,6 +182,11 @@ type Querier interface {
 	DeleteMediaItemFormat(ctx context.Context, id pgtype.UUID) error
 	DeleteMediaRating(ctx context.Context, arg DeleteMediaRatingParams) error
 	DeleteMediaReview(ctx context.Context, arg DeleteMediaReviewParams) error
+	// Admin-only removal (handler checks role); episodes cascade via
+	// media_items.source_feed_id ON DELETE CASCADE.
+	DeletePodcastFeed(ctx context.Context, id pgtype.UUID) (int64, error)
+	// Unsubscribe NEVER deletes feed/episode/file state (D6).
+	DeletePodcastSubscription(ctx context.Context, arg DeletePodcastSubscriptionParams) (int64, error)
 	DeleteProcessingIssue(ctx context.Context, id pgtype.UUID) (ProcessingIssues, error)
 	DeleteReadingProgress(ctx context.Context, arg DeleteReadingProgressParams) error
 	DeleteSavedFilter(ctx context.Context, arg DeleteSavedFilterParams) (SavedFilters, error)
@@ -421,6 +448,17 @@ type Querier interface {
 	// Get OPDS tokens by device
 	GetOpdsTokensByDevice(ctx context.Context, deviceID pgtype.UUID) ([]OpdsTokens, error)
 	GetPanelData(ctx context.Context, arg GetPanelDataParams) (PanelData, error)
+	GetPodcastEpisode(ctx context.Context, id pgtype.UUID) (MediaItems, error)
+	GetPodcastFeed(ctx context.Context, id pgtype.UUID) (PodcastFeeds, error)
+	// URL-migration dedupe: same canonical guid within the library reuses
+	// the existing row.
+	GetPodcastFeedByGuid(ctx context.Context, arg GetPodcastFeedByGuidParams) (PodcastFeeds, error)
+	// The download root (purpose='podcast') of a podcasts library.
+	GetPodcastLibraryFolder(ctx context.Context, libraryID pgtype.UUID) ([]LibraryFolders, error)
+	GetPodcastSubscription(ctx context.Context, arg GetPodcastSubscriptionParams) (PodcastSubscriptions, error)
+	// The podcasts library/ies visible to the user (add-feed target list;
+	// a self-hosted instance typically has exactly one).
+	GetPodcastsLibraryForUser(ctx context.Context, userID pgtype.UUID) ([]GetPodcastsLibraryForUserRow, error)
 	// Get most popular books for a user
 	GetPopularBooks(ctx context.Context, arg GetPopularBooksParams) ([]GetPopularBooksRow, error)
 	// Single-issue read for the resolve/delete endpoints' family-lens gate.
@@ -552,6 +590,9 @@ type Querier interface {
 	ListDeletedAnnotationsForBook(ctx context.Context, arg ListDeletedAnnotationsForBookParams) ([]ListDeletedAnnotationsForBookRow, error)
 	ListDevicesByType(ctx context.Context, deviceType string) ([]Devices, error)
 	ListDevicesByUser(ctx context.Context, userID pgtype.UUID) ([]Devices, error)
+	// Download-worker policy union (D6): most aggressive policy wins for
+	// what arrives. Runs under an admin identity (background job).
+	ListFeedSubscribers(ctx context.Context, feedID pgtype.UUID) ([]ListFeedSubscribersRow, error)
 	// Items hidden from libraries: either missing from disk (waiting on the
 	// second scan that archives them) or already archived and pending purge.
 	// Feeds the admin archived-items page. match_* columns identify an active
@@ -571,11 +612,21 @@ type Querier interface {
 	// List media items that have no stored SHA-256 (imported before hashing existed)
 	ListMediaItemsMissingHash(ctx context.Context) ([]MediaItems, error)
 	ListMediaItemsSorted(ctx context.Context, arg ListMediaItemsSortedParams) ([]ListMediaItemsSortedRow, error)
+	// The podcasts page: the acting user's subscriptions with feed metadata
+	// and the user-owned subscription fields. Facet values derive in Go.
+	ListMyPodcastFeeds(ctx context.Context, userID pgtype.UUID) ([]ListMyPodcastFeedsRow, error)
 	ListPendingHashConflicts(ctx context.Context) ([]ListPendingHashConflictsRow, error)
 	// DeviceID NULL = every device's pending items (the queue processor's
 	// enumerator passes NULL; a bare `device_id = NULL` never matches, which
 	// silently disabled the offline flush until 2026-10-17).
 	ListPendingSyncQueueItems(ctx context.Context, arg ListPendingSyncQueueItemsParams) ([]SyncQueue, error)
+	// Feed detail / sequence source. RLS scopes to subscriber-or-admin;
+	// ordering: native position, then pub date, then guid (stable across
+	// re-fetches for historical rows whose position went stale).
+	ListPodcastEpisodes(ctx context.Context, sourceFeedID pgtype.UUID) ([]MediaItems, error)
+	// Poller worklist (admin identity): every feed with its validators and
+	// the back-off flag (is_complete feeds poll rarely, never disappear).
+	ListPodcastFeedsForPolling(ctx context.Context) ([]PodcastFeeds, error)
 	// LEFT JOIN (Phase 11): row-less import failures have NO media_items
 	// row — an inner join would silently drop the ledger's newest kind.
 	// Item-side projections COALESCE to keep them non-nullable strings;
@@ -583,6 +634,8 @@ type Querier interface {
 	ListProcessingIssuesByLibrary(ctx context.Context, libraryID pgtype.UUID) ([]ListProcessingIssuesByLibraryRow, error)
 	ListSyncConflictsByMediaItem(ctx context.Context, arg ListSyncConflictsByMediaItemParams) ([]SyncConflicts, error)
 	ListSyncConflictsByUser(ctx context.Context, userID pgtype.UUID) ([]ListSyncConflictsByUserRow, error)
+	// Download All + policy union worklist.
+	ListUndownloadedEpisodes(ctx context.Context, sourceFeedID pgtype.UUID) ([]MediaItems, error)
 	// List unresolved unlinked books with pagination
 	ListUnresolvedUnlinkedBooks(ctx context.Context, arg ListUnresolvedUnlinkedBooksParams) ([]ListUnresolvedUnlinkedBooksRow, error)
 	// Page list: unresolved queue rows for the caller's own devices (ignored
@@ -591,6 +644,14 @@ type Querier interface {
 	ListUsers(ctx context.Context) ([]ListUsersRow, error)
 	// First consecutive scan that cannot find the file on disk.
 	MarkMediaItemMissing(ctx context.Context, id pgtype.UUID) error
+	// SUCCESS-only write (invariant 7): the file is on disk and probed.
+	// ffprobe facts (real duration via audio_metadata, precise size/mime)
+	// reconcile the feed's declared values.
+	MarkPodcastEpisodeDownloaded(ctx context.Context, arg MarkPodcastEpisodeDownloadedParams) (MediaItems, error)
+	// Failure/rejection write: state + reason + whether a human already
+	// intervened (manual_retry resets the auto-retry budget). Existing
+	// metadata/file facts are never cleared.
+	MarkPodcastEpisodeFailed(ctx context.Context, arg MarkPodcastEpisodeFailedParams) error
 	// Content reappeared at a new location while the old path vanished: treat as
 	// a move. Repoints the row (and refreshes file-level fields) so reading
 	// history follows the book; archive/missing state is cleared separately.
@@ -654,14 +715,30 @@ type Querier interface {
 	// Search Media Items queries
 	SearchMediaItems(ctx context.Context, arg SearchMediaItemsParams) ([]SearchMediaItemsRow, error)
 	SearchMediaItemsUnified(ctx context.Context, arg SearchMediaItemsUnifiedParams) ([]SearchMediaItemsUnifiedRow, error)
+	// Subscription-scoped episode search (D14): title + description cover
+	// un-downloaded AND historical rows (fetcher persists metadata-only).
+	// RLS already restricts to the caller's subscriptions — the explicit
+	// source filter keeps scan items out of podcast search.
+	SearchMyPodcastEpisodes(ctx context.Context, dollar_1 interface{}) ([]MediaItems, error)
+	// Feed-title AND subscription-display-name search (D14) + the facet
+	// fields the podcasts page filters on.
+	SearchMyPodcastFeeds(ctx context.Context, arg SearchMyPodcastFeedsParams) ([]SearchMyPodcastFeedsRow, error)
 	SearchNarratorValues(ctx context.Context, arg SearchNarratorValuesParams) ([]SearchNarratorValuesRow, error)
 	SearchSeriesValues(ctx context.Context, arg SearchSeriesValuesParams) ([]SearchSeriesValuesRow, error)
 	SearchTagsValues(ctx context.Context, arg SearchTagsValuesParams) ([]SearchTagsValuesRow, error)
 	SetDeviceSyncEnabled(ctx context.Context, arg SetDeviceSyncEnabledParams) (Devices, error)
 	// Library Visibility queries
 	SetLibraryVisibility(ctx context.Context, arg SetLibraryVisibilityParams) (LibraryVisibility, error)
+	// Worker claim: pending|failed -> queued. Attempts incremented at
+	// claim time so a crashed worker still counts the try.
+	SetPodcastEpisodeDownloadQueued(ctx context.Context, id pgtype.UUID) (int64, error)
+	SetPodcastEpisodeDownloading(ctx context.Context, id pgtype.UUID) error
+	// Manual retry (same endpoint as download): reset to pending so the
+	// worker re-claims it; the reason text clears with the fresh attempt.
+	SetPodcastEpisodePending(ctx context.Context, id pgtype.UUID) error
 	// Set system config
 	SetSystemConfig(ctx context.Context, arg SetSystemConfigParams) (SystemConfig, error)
+	SubscribePodcastFeed(ctx context.Context, arg SubscribePodcastFeedParams) (PodcastSubscriptions, error)
 	SyncLibraryTypeExtensions(ctx context.Context, arg SyncLibraryTypeExtensionsParams) error
 	TombstoneMediaBookmarkByDedupKey(ctx context.Context, arg TombstoneMediaBookmarkByDedupKeyParams) error
 	TombstoneMediaBookmarkByID(ctx context.Context, arg TombstoneMediaBookmarkByIDParams) error
@@ -726,6 +803,20 @@ type Querier interface {
 	UpdateMediaNoteForSync(ctx context.Context, arg UpdateMediaNoteForSyncParams) (MediaNotes, error)
 	UpdateMediaRating(ctx context.Context, arg UpdateMediaRatingParams) (MediaRatings, error)
 	UpdatePassword(ctx context.Context, arg UpdatePasswordParams) error
+	UpdatePodcastFeedArtwork(ctx context.Context, arg UpdatePodcastFeedArtworkParams) error
+	// Post-fetch bookkeeping: validators for conditional GETs, the fetch
+	// timestamp, and the feed's own last-build marker.
+	UpdatePodcastFeedFetch(ctx context.Context, arg UpdatePodcastFeedFetchParams) (PodcastFeeds, error)
+	// Fetcher-only full metadata refresh (parse result). podcast_guid is
+	// set once a feed declares it; new_feed_url handling is a dedicated
+	// query below.
+	UpdatePodcastFeedMetadata(ctx context.Context, arg UpdatePodcastFeedMetadataParams) (PodcastFeeds, error)
+	// itunes:new-feed-url (or a permanent HTTP redirect chain): the feed has
+	// MOVED. Rewrite feed_url so future polls hit the new location; the row
+	// (and every subscription/episode) stays put.
+	UpdatePodcastFeedRedirect(ctx context.Context, arg UpdatePodcastFeedRedirectParams) error
+	// User-owned fields only (D9): display name + auto-download policy.
+	UpdatePodcastSubscription(ctx context.Context, arg UpdatePodcastSubscriptionParams) (PodcastSubscriptions, error)
 	UpdateReadingProgress(ctx context.Context, arg UpdateReadingProgressParams) (ReadingProgress, error)
 	UpdateReadingSpeed(ctx context.Context, arg UpdateReadingSpeedParams) (ReadingSpeed, error)
 	UpdateSavedFilter(ctx context.Context, arg UpdateSavedFilterParams) (SavedFilters, error)
@@ -751,6 +842,17 @@ type Querier interface {
 	// content identical), and after a manifest-gated re-extract.
 	UpsertMediaScanState(ctx context.Context, arg UpsertMediaScanStateParams) error
 	UpsertPanelData(ctx context.Context, arg UpsertPanelDataParams) (PanelData, error)
+	// ============================================================================
+	// Podcast episodes — media_items rows with source='podcast_episode'
+	// ============================================================================
+	// Fetcher-only upsert keyed on the partial unique index
+	// (source_feed_id, episode_guid). DO UPDATE refreshes FETCH-OWNED
+	// metadata only. Write-after-success guard (AGENTS.md gotcha #7):
+	// download state/error/attempts are NEVER touched here, and the
+	// downloaded file's facts (path/size/mime/cover) survive renumbering —
+	// only un-downloaded rows follow the re-derived file_path.
+	// authors_search mirrors authors (trigram search column).
+	UpsertPodcastEpisode(ctx context.Context, arg UpsertPodcastEpisodeParams) (MediaItems, error)
 	UpsertReaderSettings(ctx context.Context, arg UpsertReaderSettingsParams) (ReaderSettings, error)
 	UpsertSystemSetting(ctx context.Context, arg UpsertSystemSettingParams) (SystemSettings, error)
 	// Ingest: insert or refresh the queue row for a device file that could not