PR-D4: pick support for dynamic feature sources

docs/design/dynamic-source-pick.md

@@ -0,0 +1,162 @@
+# Dynamic Source Pick — Design Note (PR-D4)
+
+> Status: **In progress** — describes the click-to-identify support
+> for dynamic feature sources shipped by PR-D4. See
+> [Dynamic feature sources](dynamic-feature-source.md) for the
+> underlying push-driven abstraction (PR-D1) and
+> [AIS dynamic feature source](ais-source.md) for the motivating
+> AIS overlay (PR-D3).
+
+## 0. Problem
+
+PR-D3 wired AIS targets and own-ship onto the map via
+`DynamicSourceOverlayHost`. The overlay layers are pure rendering —
+they carry no Mapsui feature attributes and are *not* enumerated by
+the existing `IPickService.HandlePick(MapInfo)` path, which only
+walks dataset-owned layers. Clicking an AIS target therefore does
+nothing.
+
+PR-D4 closes the gap: a click anywhere on the map collects both
+dataset hits (existing path) and dynamic-source hits (new path) and
+displays them side-by-side in the Pick Report panel.
+
+## 1. Decisions
+
+### Q1. Pick-hit shape — **sibling type**
+
+`DynamicPickHit` is a new internal record next to `PickHit`.
+
+```
+internal sealed record DynamicPickHit(
+    string SourceId,
+    string SourceDisplayName,
+    string FeatureId,
+    string? Kind,
+    string DisplayLabel,
+    DateTimeOffset LastUpdated,
+    double Latitude,
+    double Longitude,
+    DynamicMotion? Motion,
+    DynamicVesselGeometry? VesselGeometry,
+    IReadOnlyList<DynamicPickAttributeRow> Attributes);
+```
+
+Rationale: `PickHit` is dataset-centric (FC-decoded feature type,
+xlink references, dataset file name, station chart VM). Dynamic
+features have a fundamentally different identity model — opaque
+string id (MMSI for AIS, `"ownship"`), no FC, mutable position, free-
+form `Attributes` dictionary. Mixing them invites optional-field
+bloat. The pick report panel renders both with a small dispatch.
+
+### Q2. Hit-test geometry & tolerance — **12 device-pixel radius, point-distance only for v1**
+
+Hit testing happens in projected map units (Spherical Mercator). The
+click delivers `(MPoint mapPoint, double resolution)`; tolerance is
+`12 * resolution` (12 device pixels at the current zoom). Dynamic
+features are converted with `SphericalMercator.FromLonLat`.
+
+For v1 the tester treats every dynamic feature as a point regardless
+of its `GeometryType` — only `Point` features ship today
+(own-ship + AIS). When line/polygon dynamic features land they will
+get their own paths via `Geometry.Distance`; this is noted in the
+contract docs but unimplemented.
+
+Per-renderer custom tolerance (e.g. "anywhere inside the hull
+polygon") is **out of scope for v1** — see §3.
+
+### Q3. Where pick is wired — **separate `IDynamicSourcePickService`**
+
+A new service runs alongside `IPickService`. The click handler
+(`MapInteractionController`) computes the world position from the
+`MapInfo`, asks the dynamic-source service for hits, and forwards
+both result lists to `IPickService.HandlePick(MapInfo, IReadOnlyList<DynamicPickHit>)`.
+The pick service publishes both into `PickReportViewModel`.
+
+Reasons:
+- Different storage (registry of `IDynamicFeatureSource` vs loader
+  of `IDatasetProcessor`).
+- Easier to test (no `MapInfo` mocking; pure pixel math).
+- Keeps `PickService` from becoming a god service.
+
+### Q4. Pick report panel UI — **sectioned single list**
+
+The panel grows a third section between the dataset hit-list and
+the identity / attributes block:
+
+```
+┌─ FEATURES (3)              ─┐  ← existing dataset hit list (>1)
+│  • Cargo vessel — MV ALPHA   │
+│  • DepthArea — 12345         │
+└──────────────────────────────┘
+┌─ DYNAMIC FEATURES (1)      ─┐  ← new: shown when DynamicHits ≠ ∅
+│  AIS — vessel.ais.cargo      │
+│    MV ALPHA · 4s ago         │
+│    47.602°N 122.330°W        │
+│    COG 270° · SOG 12.4 kn    │
+│    MMSI: 367123456            │
+│    …                          │
+└──────────────────────────────┘
+[identity / references / attributes block — dataset only]
+```
+
+Both sections are visible at once when both have hits. Dataset
+section is hidden when `Hits.Count == 0`; dynamic section is hidden
+when `DynamicHits.Count == 0`. `HasPick` is now true if **either**
+list is non-empty.
+
+### Q5. Localisation — **all new strings via Strings.resx**
+
+Keys added: `PickReport_DynamicSection`, `PickReport_LastUpdatedRelative`,
+`PickReport_Mmsi`, `PickReport_VesselName`, `PickReport_CallSign`,
+`PickReport_Heading`, `PickReport_Cog`, `PickReport_Sog`,
+`PickReport_Dimensions`, `PickReport_Position`, `Tooltip_DynamicHit`.
+Tooltips on every new control.
+
+### Q6. Selection / highlight — **deferred**
+
+A future PR will add an S-52-style square selection ring drawn
+around the picked dynamic feature. Out of scope for PR-D4.
+
+## 2. Threading & lifetime
+
+- `DynamicSourcePickService` is constructed against the existing
+  `DynamicFeatureSourceRegistryAccessor` (late-bound; the host
+  attaches the registry when MainWindow finishes wiring). When the
+  registry is unattached, `Pick(...)` returns an empty list — the
+  click is a dataset-only pick, not an error.
+- `IDynamicFeatureSource.CurrentFeatures` is documented as safe from
+  any thread; the pick service is called on the UI thread (click
+  handler) and reads the immutable snapshot.
+- The hit-tester is pure and stateless; tests drive it directly.
+
+## 3. Out of scope
+
+- Selection ring / highlight on the map.
+- ARPA-style multi-target track viewer.
+- AIS aids-to-navigation, base stations, SAR aircraft.
+- CPA / TCPA computations.
+- Picking on time-step coverage products (S-102 / S-104 / S-111) —
+  goes through dataset pick.
+- Server-side / MCP exposure of dynamic picks.
+- Per-source custom hit-test geometry (e.g. polygon hull regions).
+  Easy follow-up: the `IDynamicSourceHitTester` becomes pluggable
+  per `RendererKey`.
+
+## 4. Test surfaces
+
+- `DynamicSourceHitTesterTests` — point-in-tolerance hits, miss,
+  visibility filter, ordering by distance, multiple sources.
+- `DynamicSourcePickServiceTests` — integration with a fake
+  registry; hits flow through the registry accessor.
+- `PickReportViewModelTests` — `SetDynamicPicks` populates the
+  `DynamicHits` collection and flips `HasPick` true; clears revert.
+- `PickServiceTests` — calling `HandlePick(null, dynamicHits)`
+  publishes the dynamic hits even with no `MapInfo`.
+
+## 5. References
+
+- S-52 / IEC 62388 — vessel symbology and pick ergonomics.
+- IEC 61174 §8 — ECDIS interrogation requirements (aspirational;
+  the standard does not normatively define dynamic-target
+  interrogation, but the "show all object info under the cursor"
+  pattern is the governing convention).

docs/toc.yml

@@ -14,5 +14,7 @@
       href: design/own-ship-symbology.md
     - name: AIS dynamic feature source
       href: design/ais-source.md
+    - name: Dynamic source pick
+      href: design/dynamic-source-pick.md
     - name: S-98 interoperability
       href: design/s98-interoperability.md

src/EncDotNet.S100.Viewer/App.axaml.cs

@@ -248,6 +248,9 @@ private static IServiceProvider ConfigureServices()
         services.AddSingleton<IToastService, ToastService>();
         services.AddSingleton<IDatasetLoaderService, DatasetLoaderService>();
         services.AddSingleton<IPickService, PickService>();
+        services.AddSingleton<EncDotNet.S100.Viewer.Services.DynamicSources.IDynamicSourcePickService>(sp =>
+            new EncDotNet.S100.Viewer.Services.DynamicSources.DynamicSourcePickService(
+                sp.GetRequiredService<EncDotNet.S100.Viewer.Services.DynamicSources.DynamicFeatureSourceRegistryAccessor>()));
         services.AddSingleton<IFeatureSearchService, FeatureSearchService>();
         services.AddSingleton<IFileDialogService, FileDialogService>();
         services.AddSingleton<IExchangeSetService, ExchangeSetService>();

src/EncDotNet.S100.Viewer/MainWindow.axaml.cs

@@ -279,7 +279,11 @@ internal MainWindow(
         // Enable trackpad pan/pinch/rotate gestures, single/double-tap pick,
         // long-press pick, mouse lat/lon readout, scale-bar/compass viewport
         // sync, and the zoom in/out overlay buttons.
-        var interactionController = new MapInteractionController(_viewModel, _pickService, _loader);
+        var interactionController = new MapInteractionController(
+            _viewModel,
+            _pickService,
+            _loader,
+            App.Services.GetService<EncDotNet.S100.Viewer.Services.DynamicSources.IDynamicSourcePickService>());
         interactionController.Attach(MapControl, ZoomInButton, ZoomOutButton, ZoomToExtentButton, ScaleBar, CompassRose);
 
         // Wire the map-tool controller to the map: tools are registered with

src/EncDotNet.S100.Viewer/README.md

@@ -236,6 +236,20 @@ Own-ship visibility is controlled by its row in the **Dynamic
 Arrows** plane of the Layer Stack panel and is persisted between
 sessions.
 
+### Picking dynamic features
+
+Click (or long-press, on touch) on any dynamic-source target
+— own-ship, an AIS vessel pictogram — to identify it. The
+**Pick Report** panel renders a *Dynamic sources* section above
+the dataset hits showing the source display name, feature kind,
+last-updated relative time, position, course / heading / speed
+when available, and the full attribute snapshot (MMSI, vessel
+name, call sign, etc. for AIS). Dataset and dynamic hits stack in
+one panel so a single click reveals everything under the
+crosshair. The hit-test radius is 12 device pixels (matches the
+AIS pictogram outer disc). See
+[`docs/design/dynamic-source-pick.md`](../../docs/design/dynamic-source-pick.md).
+
 ## Optional MCP server
 
 The viewer can optionally host a Model Context Protocol server

src/EncDotNet.S100.Viewer/Resources/Strings.cs

@@ -425,4 +425,25 @@ private static string Get(string name) =>
     public static string Settings_AisApiKeyTooltip => Get(nameof(Settings_AisApiKeyTooltip));
     public static string Settings_AisApiKey_EnvVarHint => Get(nameof(Settings_AisApiKey_EnvVarHint));
     public static string Settings_AisApiKey_EnvVarPresent => Get(nameof(Settings_AisApiKey_EnvVarPresent));
+
+    // PR-D4: Dynamic-source pick report.
+    public static string PickReport_DynamicSection => Get(nameof(PickReport_DynamicSection));
+    public static string PickReport_LastUpdatedRelative => Get(nameof(PickReport_LastUpdatedRelative));
+    public static string PickReport_LastUpdatedSecondsAgo => Get(nameof(PickReport_LastUpdatedSecondsAgo));
+    public static string PickReport_LastUpdatedMinutesAgo => Get(nameof(PickReport_LastUpdatedMinutesAgo));
+    public static string PickReport_LastUpdatedHoursAgo => Get(nameof(PickReport_LastUpdatedHoursAgo));
+    public static string PickReport_LastUpdatedJustNow => Get(nameof(PickReport_LastUpdatedJustNow));
+    public static string PickReport_Position => Get(nameof(PickReport_Position));
+    public static string PickReport_PositionFormat => Get(nameof(PickReport_PositionFormat));
+    public static string PickReport_Cog => Get(nameof(PickReport_Cog));
+    public static string PickReport_Heading => Get(nameof(PickReport_Heading));
+    public static string PickReport_Sog => Get(nameof(PickReport_Sog));
+    public static string PickReport_DegreesFormat => Get(nameof(PickReport_DegreesFormat));
+    public static string PickReport_KnotsFormat => Get(nameof(PickReport_KnotsFormat));
+    public static string PickReport_Dimensions => Get(nameof(PickReport_Dimensions));
+    public static string PickReport_DimensionsFormat => Get(nameof(PickReport_DimensionsFormat));
+    public static string PickReport_Mmsi => Get(nameof(PickReport_Mmsi));
+    public static string PickReport_VesselName => Get(nameof(PickReport_VesselName));
+    public static string PickReport_CallSign => Get(nameof(PickReport_CallSign));
+    public static string Tooltip_DynamicHit => Get(nameof(Tooltip_DynamicHit));
 }

src/EncDotNet.S100.Viewer/Resources/Strings.resx

@@ -1126,4 +1126,70 @@ Open an S-101, S-124, S-125, S-201, or S-421 dataset to see display controls her
     <value>Environment variable {0} is set; it will be used.</value>
     <comment>{0} = environment variable name.</comment>
   </data>
+
+  <!-- PR-D4: Dynamic-source pick report -->
+  <data name="PickReport_DynamicSection" xml:space="preserve">
+    <value>DYNAMIC FEATURES ({0})</value>
+    <comment>{0} = count of dynamic hits.</comment>
+  </data>
+  <data name="PickReport_LastUpdatedRelative" xml:space="preserve">
+    <value>Updated {0}</value>
+    <comment>{0} = formatted relative time string (e.g. "3s ago").</comment>
+  </data>
+  <data name="PickReport_LastUpdatedSecondsAgo" xml:space="preserve">
+    <value>{0}s ago</value>
+    <comment>{0} = whole seconds since the feature was updated.</comment>
+  </data>
+  <data name="PickReport_LastUpdatedMinutesAgo" xml:space="preserve">
+    <value>{0}m ago</value>
+    <comment>{0} = whole minutes since the feature was updated.</comment>
+  </data>
+  <data name="PickReport_LastUpdatedHoursAgo" xml:space="preserve">
+    <value>{0}h ago</value>
+    <comment>{0} = whole hours since the feature was updated.</comment>
+  </data>
+  <data name="PickReport_LastUpdatedJustNow" xml:space="preserve">
+    <value>just now</value>
+  </data>
+  <data name="PickReport_Position" xml:space="preserve">
+    <value>Position</value>
+  </data>
+  <data name="PickReport_PositionFormat" xml:space="preserve">
+    <value>{0:F4}°, {1:F4}°</value>
+    <comment>{0} = latitude, {1} = longitude. Use invariant culture.</comment>
+  </data>
+  <data name="PickReport_Cog" xml:space="preserve">
+    <value>COG</value>
+  </data>
+  <data name="PickReport_Heading" xml:space="preserve">
+    <value>Heading</value>
+  </data>
+  <data name="PickReport_Sog" xml:space="preserve">
+    <value>SOG</value>
+  </data>
+  <data name="PickReport_DegreesFormat" xml:space="preserve">
+    <value>{0:F1}°</value>
+  </data>
+  <data name="PickReport_KnotsFormat" xml:space="preserve">
+    <value>{0:F1} kn</value>
+  </data>
+  <data name="PickReport_Dimensions" xml:space="preserve">
+    <value>Dimensions</value>
+  </data>
+  <data name="PickReport_DimensionsFormat" xml:space="preserve">
+    <value>{0:F0} m × {1:F0} m</value>
+    <comment>{0} = length, {1} = beam, in metres.</comment>
+  </data>
+  <data name="PickReport_Mmsi" xml:space="preserve">
+    <value>MMSI</value>
+  </data>
+  <data name="PickReport_VesselName" xml:space="preserve">
+    <value>Name</value>
+  </data>
+  <data name="PickReport_CallSign" xml:space="preserve">
+    <value>Call sign</value>
+  </data>
+  <data name="Tooltip_DynamicHit" xml:space="preserve">
+    <value>Dynamic-source feature picked from the live overlay.</value>
+  </data>
 </root>

src/EncDotNet.S100.Viewer/Services/DynamicSources/DynamicFeatureSourceRegistryAccessor.cs

@@ -1,5 +1,6 @@
 using System;
 using System.Collections.Generic;
+using EncDotNet.S100.DynamicSources;
 
 namespace EncDotNet.S100.Viewer.Services.DynamicSources;
 
@@ -58,6 +59,9 @@ public IDynamicFeatureSourceRegistry? Current
 
     public bool GetVisible(string sourceId) => _current?.GetVisible(sourceId) ?? true;
 
+    public IReadOnlyList<IDynamicFeatureSource> GetVisibleSourceInstances() =>
+        _current?.GetVisibleSourceInstances() ?? Array.Empty<IDynamicFeatureSource>();
+
     public void SetVisible(string sourceId, bool visible) =>
         _current?.SetVisible(sourceId, visible);