feat: portal-wide device selector — session-based, all pages now use selected device

- _portal_device_id() reads from session, falls back to DEVICE_NAME env var
- GET/POST /api/v1/portal/select-device for selector data + set
- Dropdown in server base.html topbar, JS populates from API, page reloads on change
- All portal pages (overview, trips, dashcam, DTC, device settings) now use selected device

FEATURES.md

@@ -82,69 +82,15 @@ dedicated PLAN.md phase (or fold it into the relevant existing work) and mark it
     run the Pi's hotspot/SSID the same way `app_network.py` currently does.
 
 ### FEAT-05 — DTC history synced to remote server with code descriptions
-- **Status**: `IDEA`
+- **Status**: `SHIPPED` 2026-08-12
-- **Area**: `modules/app_upload.py`, `modules/app_sql.py`, `server/sql/`, `server/modules/db.py`,
+- **Area**: `modules/app_upload.py`, `server/sql/migrate_phase27_dtc.sql`, `server/modules/db.py`, `server/app.py`, `server/templates/dtc.html`
-  `server/app.py`, server portal templates
 - **Phase**: Phase 27
-- **Requested**: 2026-08-11 — owner wants DTC codes persisted to the server (not just local SQLite)
+- **What**: Pi pushes current DTC snapshot to server via `POST /api/v1/dtc/batch`.
-  with code + description, surviving until user deletes them or OBD reports the code cleared.
+  Server diffs against stored state — new codes inserted, existing updated, missing
-- **Current state (2026-08-11)**:
+  codes auto-cleared. Portal has a new `/dtc` page showing code, description, MIL
-  - Pi: `app_obd.py` polls DTCs from ECU → `app_sql.save_dtc_state()` persists MIL + codes
+  state, active/cleared status, first/last seen timestamps, and manual delete.
-    (code, description, IS_SET, FIRST_SEEN_AT, LAST_SEEN_AT) to local SQLite `dtc` table.
+  Upload skips when OBD disconnected (avoids clearing server DTCs on Pi reboot).
-  - Pi: `app_upload.py` uploads tracking rows and dashcam files — NO DTC upload path exists.
+  Snapshot is hash-compared to avoid redundant uploads.
-  - Server: NO `dtc_events` table, NO DTC API, NO portal DTC page.
-- **Design**:
-
-  **Server schema** (`server/sql/migrate_phase26_dtc.sql`):
-  ```sql
-  CREATE TABLE IF NOT EXISTS dtc_events (
-      id SERIAL PRIMARY KEY,
-      device_id INTEGER NOT NULL REFERENCES devices(id) ON DELETE CASCADE,
-      code VARCHAR(10) NOT NULL,
-      description TEXT NOT NULL DEFAULT '',
-      mil_on BOOLEAN NOT NULL DEFAULT FALSE,
-      is_active BOOLEAN NOT NULL DEFAULT TRUE,
-      first_seen_at TIMESTAMPTZ NOT NULL DEFAULT now(),
-      last_seen_at TIMESTAMPTZ NOT NULL DEFAULT now(),
-      cleared_at TIMESTAMPTZ,
-      UNIQUE (device_id, code)
-  );
-  ```
-
-  **Server API** (`server/app.py`):
-  - `POST /api/v1/dtc/batch` (device auth): receives current DTC snapshot from Pi.
-    Body: `{"mil_on": true/false, "codes": [{"code": "P0301", "description": "Cylinder 1 Misfire"}, ...]}`
-    - Insert new codes, update `last_seen_at` for existing active codes.
-    - Mark any previously-active codes NOT in this batch as `is_active=false, cleared_at=now()`.
-    - Return `{received: N, cleared: M, unchanged: K}`.
-  - `GET /api/v1/portal/dtc` (user auth): list all DTC events for configured device.
-  - `DELETE /api/v1/portal/dtc/<id>` (user auth): manual deletion.
-
-  **Server portal**: new DTC page or section showing code, description, MIL state, first/last seen,
-  active/cleared status, cleared timestamp.
-
-  **Pi upload** (`modules/app_upload.py`):
-  - New `_upload_dtc_snapshot()` — called after tracking batch in `_upload_loop()`.
-  - Only uploads when the local DTC snapshot differs from last-uploaded (hash or version compare).
-  - Reuses same `_credentials()`/`_headers()` as tracking uploads.
-  - Same WiFi-first, cellular-fallback (if configured) path as tracking batches.
-
-- **Deduplication logic**: server-side per `(device_id, code)` unique key. Pi sends the full
-  current snapshot each time. Server diffs: new codes = insert, existing = touch last_seen_at,
-  missing from snapshot = mark cleared. This means if a code disappears from the ECU, it
-  auto-clears on the server on the next upload — no manual "clear" step needed.
-- **Manual deletion**: only via the server portal delete button. Cleared codes stay visible as
-  history. The Pi never deletes from the server automatically.
-- **Outstanding considerations**:
-  - The Pi's local `save_dtc_state()` already handles IS_SET/cleared tracking — the upload path
-    just needs to read the current active snapshot from SQLite (reuse `get_persisted_dtc_state()`).
-  - DTC descriptions come directly from the ECU (python-obd's `GET_DTC` response) — they're the
-    standard SAE J2012 descriptions, no external lookup needed.
-  - Should we upload on every poll (every ~2s OBD cycle) or batch? Answer: batch. Upload alongside
-    tracking batches (every 30s idle, 1s catchup). DTCs don't change mid-drive that often.
-  - First upload after Pi reboot with no OBD connected: snapshot is empty → server marks all
-    previously-active codes as cleared. Is that desired? Probably not — should skip upload when
-    OBD is disconnected/unavailable (the Pi already knows this from `connection` state).
 
 ### FEAT-08 — Predictable IP on phone hotspot (DHCP client-id)
 - **Status**: `SHIPPED` 2026-08-11 (Phase 22)

PLAN.md

@@ -1945,35 +1945,25 @@ agree on OBD and GPS state. BUGS.md Open section is empty. readme.md project sta
 
 ---
 
-### Phase 27: Feature additions — ✅ DONE (3 shipped, 4 candidates remain)
+### Phase 27: Feature additions — ✅ DONE (4 shipped, 3 candidates remain)
-**Completed 2026-08-12.** Three features shipped; remaining 4 are low-priority ideas
+**Completed 2026-08-12.** Four features shipped; remaining 3 are low-priority ideas
 tracked in FEATURES.md.
 
 **Shipped:**
-- **FEAT-03 — Manual odometer baseline** (2026-08-11): Pi settings has "Odometer baseline
+- **FEAT-03 — Manual odometer baseline** (2026-08-11)
-  (km)". Dashboard shows `odometer_km = baseline + trip distance`. Pushes to server on save
+- **FEAT-06 — Trip ID column in history** (2026-08-11)
-  via `POST /api/device-config/push`. Portal shows read-only synced value. Server overview
+- **FEAT-07 — Phone-hotspot auto-connect docs** (2026-08-11)
-  stat card. Four sync bugs fixed during implementation:
+- **FEAT-05 — DTC history sync to server** (2026-08-12): Pi pushes DTC snapshots
-  1. Sync overwrote Pi odometer with stale server value (`_store_synced_config` no longer touches it).
+  via `POST /api/v1/dtc/batch`. Server diffs: insert/update/auto-clear. Portal
-  2. JS skipped `POST /api/device-config` when enabling sync (always-send fix).
+  `/dtc` page with code, description, MIL, status, timestamps, delete. Skips
-  3. Backend returned error when toggling sync with locked fields present (toggle-first fix).
+  upload when OBD disconnected. Changed: `modules/app_upload.py`,
-  4. `get_device_by_id()` missing `odometer_baseline` in SQL SELECT (added column, shifted indices).
+  `server/sql/migrate_phase27_dtc.sql`, `server/modules/db.py`, `server/app.py`,
-  Changed: `modules/app_settings.py`, `modules/app_sql.py`, `modules/app_device_sync.py`,
+  `server/templates/dtc.html`, `server/templates/base.html`.
-  `modules/app_device_config.py`, `templates/settings.html`, `static/js/settings.js`,
-  `server/modules/db.py`, `server/modules/device_config.py`,
-  `server/templates/device_settings.html`, `static/js/portal-device-settings.js`,
-  `server/app.py`, `FEATURES.md`.
-- **FEAT-06 — Trip ID column in history** (2026-08-11): Narrow `#ID` column on server
-  history (`data-show-id="1"`). Checkbox + batch-delete server-only (`data-batch-delete-url`).
-  Changed: `static/js/history.js`, `server/templates/history.html`.
-- **FEAT-07 — Phone-hotspot auto-connect docs** (2026-08-11): Already implemented in
-  Phase 22; documented and verified with real Pixel hardware.
 
-**Remaining candidates (4):**
+**Remaining candidates (3):**
 1. **FEAT-01** — Parallel/concurrent chunked dashcam uploads (medium)
 2. **FEAT-02** — QR / claim-code device pairing flow (medium)
 3. **FEAT-04** — Replace SIM868 2G GSM with 4G LTE modem (large)
-4. **FEAT-05** — DTC history synced to remote server (medium)
 
 ### Phase 28: Native Android companion app — 🚧 IN PROGRESS (low priority, always last)
 **Renumbered from former Phase 26 on 2026-08-10 to make room for the road-test bug-fix phase.

android/app/src/main/java/com/yarisobd/app/DashcamScreen.kt

@@ -21,6 +21,7 @@ import androidx.compose.material3.ButtonDefaults
 import androidx.compose.material3.Card
 import androidx.compose.material3.CardDefaults
 import androidx.compose.material3.CircularProgressIndicator
+import androidx.compose.material3.LinearProgressIndicator
 import androidx.compose.material3.MaterialTheme
 import androidx.compose.material3.Text
 import androidx.compose.runtime.Composable
@@ -43,6 +44,7 @@ fun DashcamScreen(
     retentionDays: Int,
     isLoading: Boolean,
     error: String?,
+    downloadProgress: Map<String, DownloadProgress>,
     onRefresh: () -> Unit,
     onDownload: (VideoFile) -> Unit,
     onDelete: (VideoFile) -> Unit,
@@ -146,8 +148,10 @@ fun DashcamScreen(
                     verticalArrangement = Arrangement.spacedBy(8.dp)
                 ) {
                     items(videos, key = { it.path }) { video ->
+                        val progress = downloadProgress[video.path]
                         VideoRow(
                             video = video,
+                            downloadProgress = progress,
                             onDownload = { onDownload(video) },
                             onDelete = { onDelete(video) },
                         )
@@ -161,6 +165,7 @@ fun DashcamScreen(
 @Composable
 private fun VideoRow(
     video: VideoFile,
+    downloadProgress: DownloadProgress?,
     onDownload: () -> Unit,
     onDelete: () -> Unit,
 ) {
@@ -224,6 +229,20 @@ private fun VideoRow(
                         style = MaterialTheme.typography.bodySmall,
                         color = MaterialTheme.colorScheme.tertiary
                     )
+                } else if (downloadProgress != null) {
+                    LinearProgressIndicator(
+                        progress = {
+                            if (downloadProgress.totalBytes > 0)
+                                downloadProgress.bytesDownloaded.toFloat() / downloadProgress.totalBytes
+                            else 0f
+                        },
+                        modifier = Modifier.fillMaxWidth().padding(top = 4.dp),
+                    )
+                    Text(
+                        text = "Downloading ${downloadProgress.bytesDownloaded / 1_000_000}MB / ${downloadProgress.totalBytes / 1_000_000}MB",
+                        style = MaterialTheme.typography.bodySmall,
+                        color = MaterialTheme.colorScheme.primary
+                    )
                 } else {
                     Text(
                         text = if (video.uploaded) "Uploaded" else "Pending",

android/app/src/main/java/com/yarisobd/app/MainActivity.kt

@@ -12,8 +12,11 @@ import androidx.compose.material3.MaterialTheme
 import androidx.compose.material3.NavigationBar
 import androidx.compose.material3.NavigationBarItem
 import androidx.compose.material3.Scaffold
+import androidx.compose.material3.SnackbarHost
+import androidx.compose.material3.SnackbarHostState
 import androidx.compose.material3.Text
 import androidx.compose.runtime.Composable
+import androidx.compose.runtime.LaunchedEffect
 import androidx.compose.runtime.collectAsState
 import androidx.compose.runtime.getValue
 import androidx.compose.runtime.mutableIntStateOf
@@ -49,10 +52,20 @@ fun YarisMainScreen(client: OkHttpClient) {
     val retentionDays by dashcamVm.retentionDays.collectAsState()
     val isLoading by dashcamVm.isLoading.collectAsState()
     val error by dashcamVm.error.collectAsState()
+    val downloadProgress by dashcamVm.downloadProgress.collectAsState()
 
+    val snackbarHostState = remember { SnackbarHostState() }
     var selectedTab by remember { mutableIntStateOf(0) }
 
+    // Show download/delete events as snackbars
+    LaunchedEffect(Unit) {
+        dashcamVm.downloadEvents.collect { event ->
+            snackbarHostState.showSnackbar(event)
+        }
+    }
+
     Scaffold(
+        snackbarHost = { SnackbarHost(snackbarHostState) },
         bottomBar = {
             NavigationBar {
                 NavigationBarItem(
@@ -78,6 +91,7 @@ fun YarisMainScreen(client: OkHttpClient) {
                     retentionDays = retentionDays,
                     isLoading = isLoading,
                     error = error,
+                    downloadProgress = downloadProgress,
                     onRefresh = { dashcamVm.loadVideos() },
                     onDownload = { dashcamVm.downloadVideo(it) },
                     onDelete = { dashcamVm.deleteVideo(it) },

server/app.py

@@ -74,12 +74,57 @@ login_manager.init_app(app)
 
 
 def _portal_device_id():
-    """Return the device id for the configured device name (single Pi setup)."""
+    """Return the device id for the user's selected device, falling back to
+    the DEVICE_NAME env var default. Selection is stored in the Flask session
+    so it persists across pages without a URL parameter on every link."""
+    # Check session first (user explicitly picked a device)
+    session_id = session.get("selected_device_id")
+    if session_id is not None:
+        dev = db.get_device_by_id(session_id)
+        if dev is not None:
+            return dev["id"]
+        # Selected device was deleted — clear stale session entry
+        session.pop("selected_device_id", None)
+    # Fall back to configured default
     name = os.environ.get("DEVICE_NAME", "yaris-2013")
     dev = db.get_device_by_name(name)
     return dev["id"] if dev else None
 
 
+@app.get("/api/v1/portal/select-device")
+@require_login
+def portal_select_device_state():
+    """Return current selection and available devices for the dropdown."""
+    devices = device_registry.list_devices()
+    configured_name = os.environ.get("DEVICE_NAME", "yaris-2013")
+    for device in devices:
+        device["portal_default"] = device["name"] == configured_name
+    current_id = session.get("selected_device_id")
+    return jsonify(
+        devices=devices,
+        selected_device_id=current_id,
+        configured_device_name=configured_name,
+    )
+
+
+@app.post("/api/v1/portal/select-device")
+@require_login
+def portal_select_device():
+    """Set the active device for the current session."""
+    body = request.get_json(silent=True) or {}
+    device_id = body.get("device_id")
+    if device_id is None:
+        session.pop("selected_device_id", None)
+        session.pop("selected_device_name", None)
+        return jsonify(status="ok", message="Device selection cleared.")
+    dev = db.get_device_by_id(int(device_id))
+    if dev is None:
+        return jsonify(error="Device not found"), 404
+    session["selected_device_id"] = dev["id"]
+    session["selected_device_name"] = dev["device_name"] or dev["name"]
+    return jsonify(status="ok", device_id=dev["id"], device_name=dev["device_name"] or dev["name"])
+
+
 @app.get("/health")
 def health():
     """Unauthenticated liveness check - used by docker-compose healthcheck

server/templates/base.html

@@ -86,7 +86,12 @@
                     <span class="fw-bold text-dark">Yaris OBD</span>
                     <span class="badge bg-warning text-dark ms-1" style="font-size:.6rem;">Remote</span>
                 </a>
-                <div class="ms-auto d-flex align-items-center gap-2">
+                <div class="d-flex align-items-center gap-2">
+                    <select class="form-select form-select-sm" id="portal-device-selector" style="width:auto;min-width:10rem;" aria-label="Select device">
+                        <option value="">Loading…</option>
+                    </select>
+                </div>
+                <div class="d-flex align-items-center gap-2">
                     <span class="text-muted small d-none d-sm-inline">{{ current_user.username }}</span>
                     <a href="{{ url_for('logout') }}" class="btn btn-outline-secondary btn-sm" title="Logout">
                         <i class="fas fa-sign-out-alt fa-fw"></i>
@@ -136,7 +141,34 @@
     <script src="{{ url_for('static', filename='js/bs-init.js') }}"></script>
     <script src="{{ url_for('static', filename='js/theme.js') }}"></script>
 
-    {# ── Shared confirmation helper ────────────────────────────────────────── #}
+    {# ── Device selector ─────────────────────────────────────────────────── #}
+    <script>
+    (function () {
+        const sel = document.getElementById("portal-device-selector");
+        if (!sel) return;
+        async function load() {
+            const r = await fetch("/api/v1/portal/select-device");
+            if (!r.ok) return;
+            const d = await r.json();
+            sel.innerHTML = d.devices.map(dev =>
+                '<option value="' + dev.id + '"' + (dev.id === d.selected_device_id ? " selected" : "") + ">" +
+                (dev.device_name || dev.name) + (dev.portal_default ? " (default)" : "") +
+                "</option>"
+            ).join("");
+            if (!d.devices.length) sel.innerHTML = '<option value="">No devices</option>';
+        }
+        load();
+        sel.addEventListener("change", async function () {
+            const id = sel.value ? parseInt(sel.value) : null;
+            await fetch("/api/v1/portal/select-device", {
+                method: "POST",
+                headers: {"Content-Type": "application/json"},
+                body: JSON.stringify({device_id: id}),
+            });
+            location.reload();
+        });
+    })();
+    </script>
     <script>
     window.confirmDelete = function(message) {
         return Promise.resolve(window.confirm(message));