Memby v0.1.53: Android TV client plus gateway

Android TV client for Emby (Kotlin, Compose for TV) and the Memby gateway
(Go, Postgres, Redis) that fronts it.

Client:
- Setup, profiles, home rows, Media3 playback, system screensaver (Dream)
- Backend chosen at build time: gateway when memby.gatewayUrl is set,
  otherwise direct to Emby. Both paths stay working.
- Server-composed home rows, rendered verbatim so new row types ship
  without an app release
- Full-screen animated maintenance state, row engagement telemetry

Gateway:
- One request per TV screen; auth, caching, search and row shaping
- Library import from Emby into Postgres (manual, then hourly incremental)
- Recommendations from viewing history (recency-weighted genre affinity)
- Admin page for imports, an offline switch, and per-row analytics
- Video always direct-plays from Emby; only metadata passes through

Identity is com.ponzischeme89.memby throughout, replacing
com.mattcohen.embyclientsname. A changed applicationId installs as a new
app: TVs need a fresh sign-in and the old package uninstalled.

Co-Authored-By: Claude Opus 5 <noreply@anthropic.com>

server/internal/api/analytics.go

@@ -0,0 +1,102 @@
+package api
+
+import (
+	"encoding/json"
+	"net/http"
+	"time"
+
+	"github.com/ponzischeme89/memby/server/internal/store"
+)
+
+// maxAnalyticsBatch caps one upload. The TV batches events and flushes periodically, so
+// a larger payload than this means something has gone wrong client-side.
+const maxAnalyticsBatch = 200
+
+// maxDwellMs discards implausible dwell times — a TV left on a row overnight says
+// nothing about what anyone was looking at.
+const maxDwellMs = 30 * 60 * 1000
+
+type rowEventPayload struct {
+	RowID      string `json:"rowId"`
+	RowKind    string `json:"rowKind"`
+	Event      string `json:"event"`
+	ItemID     string `json:"itemId"`
+	DwellMs    int    `json:"dwellMs"`
+	OccurredAt string `json:"occurredAt"`
+}
+
+type analyticsRequest struct {
+	Events []rowEventPayload `json:"events"`
+}
+
+// handleRowAnalytics accepts a batch of row engagement events from a TV.
+//
+// Fire-and-forget by design: the client does not retry, and a rejected event is never
+// worth surfacing on screen. Bad events are dropped individually rather than failing the
+// batch.
+func (s *Server) handleRowAnalytics(w http.ResponseWriter, r *http.Request, sess store.Session) {
+	var req analyticsRequest
+	if err := json.NewDecoder(http.MaxBytesReader(w, r.Body, 64<<10)).Decode(&req); err != nil {
+		writeError(w, http.StatusBadRequest, "malformed request body")
+		return
+	}
+	if len(req.Events) > maxAnalyticsBatch {
+		req.Events = req.Events[:maxAnalyticsBatch]
+	}
+
+	now := time.Now().UTC()
+	events := make([]store.RowEvent, 0, len(req.Events))
+	for _, payload := range req.Events {
+		event, ok := toRowEvent(payload, sess.EmbyUserID, now)
+		if !ok {
+			continue
+		}
+		events = append(events, event)
+	}
+
+	if err := s.store.InsertRowEvents(r.Context(), events); err != nil {
+		s.log.Warn("row analytics write failed", "error", err)
+		// Still a 204: telemetry must never make the TV think something is broken.
+	}
+	w.WriteHeader(http.StatusNoContent)
+}
+
+func toRowEvent(payload rowEventPayload, userID string, now time.Time) (store.RowEvent, bool) {
+	if payload.RowID == "" {
+		return store.RowEvent{}, false
+	}
+	switch payload.Event {
+	case store.RowEventImpression, store.RowEventFocus, store.RowEventSelect:
+	default:
+		return store.RowEvent{}, false
+	}
+
+	occurredAt := now
+	if payload.OccurredAt != "" {
+		if parsed, err := time.Parse(time.RFC3339, payload.OccurredAt); err == nil {
+			// Trust the device's clock only within a sane window; TVs are notorious for
+			// waking up in 1970.
+			if parsed.After(now.Add(-24*time.Hour)) && parsed.Before(now.Add(time.Hour)) {
+				occurredAt = parsed.UTC()
+			}
+		}
+	}
+
+	dwell := payload.DwellMs
+	if dwell < 0 {
+		dwell = 0
+	}
+	if dwell > maxDwellMs {
+		dwell = maxDwellMs
+	}
+
+	return store.RowEvent{
+		OccurredAt: occurredAt,
+		UserID:     userID,
+		RowID:      payload.RowID,
+		RowKind:    payload.RowKind,
+		Event:      payload.Event,
+		ItemID:     payload.ItemID,
+		DwellMs:    dwell,
+	}, true
+}