feat(fishing): SST raster layer from NOAA CoastWatch

Adds SST source/layer to MapLayerManager, SST toggle to LayerPickerSheet
UI and wires it up in MainActivity.

Co-Authored-By: Claude Sonnet 4.6 <noreply@anthropic.com>

3 files changed, 36 insertions, 0 deletions

diff --git a/android-app/app/src/main/kotlin/org/terst/nav/MainActivity.kt b/android-app/app/src/main/kotlin/org/terst/nav/MainActivity.kt
index fcfc96a..cfc8d6d 100644
--- a/android-app/app/src/main/kotlin/org/terst/nav/MainActivity.kt
+++ b/android-app/app/src/main/kotlin/org/terst/nav/MainActivity.kt
@@ -427,6 +427,10 @@ class MainActivity : AppCompatActivity(), SafetyFragment.SafetyListener {
                 val style = loadedStyleFlow.value ?: return@LayerPickerSheet
                 mapHandler?.setFadLayerVisible(style, enabled)
             },
+            onSstChanged       = { enabled ->
+                val style = loadedStyleFlow.value ?: return@LayerPickerSheet
+                layerManager.setSstEnabled(style, enabled)
+            },
             unitPrefs          = unitPrefs,
             onUnitsChanged     = { refreshUnits() }
         )
diff --git a/android-app/app/src/main/kotlin/org/terst/nav/ui/LayerPickerSheet.kt b/android-app/app/src/main/kotlin/org/terst/nav/ui/LayerPickerSheet.kt
index a9dcca8..b654184 100644
--- a/android-app/app/src/main/kotlin/org/terst/nav/ui/LayerPickerSheet.kt
+++ b/android-app/app/src/main/kotlin/org/terst/nav/ui/LayerPickerSheet.kt
@@ -23,6 +23,7 @@ class LayerPickerSheet(
     private val onSeamarksChanged: (Boolean) -> Unit,
     private val onDepthChanged: (Boolean) -> Unit,
     private val onFadsChanged: (Boolean) -> Unit,
+    private val onSstChanged: (Boolean) -> Unit,
     private val unitPrefs: UnitPrefs,
     private val onUnitsChanged: () -> Unit
 ) : BottomSheetDialogFragment() {
@@ -78,6 +79,11 @@ class LayerPickerSheet(
         fadsSwitch.isChecked = manager.fadsEnabled
         fadsSwitch.setOnCheckedChangeListener { _, checked -> onFadsChanged(checked) }
 
+        // ── SST switch ────────────────────────────────────────────────────────
+        val sstSwitch = view.findViewById<SwitchMaterial>(R.id.switch_sst)
+        sstSwitch.isChecked = manager.sstEnabled
+        sstSwitch.setOnCheckedChangeListener { _, checked -> onSstChanged(checked) }
+
         // ── Temperature chips ─────────────────────────────────────────────────
         val chipTemp = view.findViewById<ChipGroup>(R.id.chip_group_temp)
         chipTemp.check(when (unitPrefs.tempUnit) {
diff --git a/android-app/app/src/main/kotlin/org/terst/nav/ui/MapLayerManager.kt b/android-app/app/src/main/kotlin/org/terst/nav/ui/MapLayerManager.kt
index 33072c4..9f7e819 100644
--- a/android-app/app/src/main/kotlin/org/terst/nav/ui/MapLayerManager.kt
+++ b/android-app/app/src/main/kotlin/org/terst/nav/ui/MapLayerManager.kt
@@ -38,6 +38,8 @@ class MapLayerManager(context: Context) {
         private set
     var fadsEnabled: Boolean     = prefs.getBoolean(KEY_FADS,         false)
         private set
+    var sstEnabled: Boolean      = prefs.getBoolean(KEY_SST,          false)
+        private set
 
     // ── Source / Layer IDs ────────────────────────────────────────────────────
 
@@ -53,6 +55,8 @@ class MapLayerManager(context: Context) {
         const val LAYER_WIND       = "wind-layer"
         const val LAYER_SEAMARKS   = "openseamap-layer"
         const val LAYER_DEPTH      = "osm-depth-layer"
+        const val SOURCE_SST       = "sst-source"
+        const val LAYER_SST        = "sst-layer"
 
         private const val KEY_BASE        = "base_preset"
         private const val KEY_WIND        = "wind_enabled"
@@ -61,6 +65,7 @@ class MapLayerManager(context: Context) {
         private const val KEY_SEAMARKS    = "seamarks_enabled"
         private const val KEY_DEPTH       = "depth_enabled"
         private const val KEY_FADS        = "fads_enabled"
+        private const val KEY_SST         = "sst_enabled"
 
         // Tile URLs
         private const val URL_SATELLITE =
@@ -74,6 +79,12 @@ class MapLayerManager(context: Context) {
         // Depth soundings + contours from OpenSeaMap (zoom 3–18, coverage varies by region)
         private const val URL_DEPTH =
             "https://tiles.openseamap.org/depth/{z}/{x}/{y}.png"
+        // Sea Surface Temperature from NOAA CoastWatch (WMS-style raster)
+        private const val URL_SST =
+            "https://coastwatch.pfeg.noaa.gov/erddap/wms/jplMURSST41/request" +
+            "?SERVICE=WMS&REQUEST=GetMap&LAYERS=jplMURSST41:analysed_sst" +
+            "&BBOX={bbox-epsg-3857}&FORMAT=image/png&TRANSPARENT=TRUE" +
+            "&CRS=EPSG:3857&WIDTH=256&HEIGHT=256&VERSION=1.3.0&STYLES="
     }
 
     /**
@@ -98,6 +109,9 @@ class MapLayerManager(context: Context) {
         builder.withSource(RasterSource(SOURCE_DEPTH,
             TileSet("2.2.0", URL_DEPTH).also { it.setMinZoom(3f); it.setMaxZoom(18f) }, 256))
 
+        builder.withSource(RasterSource(SOURCE_SST,
+            TileSet("2.2.0", URL_SST), 256))
+
         // ── Layers (bottom → top within raster stack) ─────────────────────────
         builder.withLayer(RasterLayer(LAYER_SATELLITE, SOURCE_SATELLITE).apply {
             setProperties(PropertyFactory.rasterOpacity(1f))
@@ -114,6 +128,11 @@ class MapLayerManager(context: Context) {
             setProperties(PropertyFactory.visibility(if (windEnabled) "visible" else "none"))
         })
 
+        builder.withLayer(RasterLayer(LAYER_SST, SOURCE_SST).apply {
+            setProperties(PropertyFactory.rasterOpacity(0.65f))
+            setProperties(PropertyFactory.visibility(if (sstEnabled) "visible" else "none"))
+        })
+
         // Depth contours sit below seamarks so soundings don't obscure nav aid symbols
         builder.withLayer(RasterLayer(LAYER_DEPTH, SOURCE_DEPTH).apply {
             setProperties(PropertyFactory.rasterOpacity(0.85f))
@@ -159,6 +178,13 @@ class MapLayerManager(context: Context) {
             PropertyFactory.visibility(if (enabled) "visible" else "none"))
     }
 
+    fun setSstEnabled(style: Style, enabled: Boolean) {
+        sstEnabled = enabled
+        prefs.edit().putBoolean(KEY_SST, enabled).apply()
+        style.getLayer(LAYER_SST)?.setProperties(
+            PropertyFactory.visibility(if (enabled) "visible" else "none"))
+    }
+
     /** FADs are a GeoJSON vector layer in MapHandler; this just persists the pref. */
     fun setFadsEnabled(enabled: Boolean) {
         fadsEnabled = enabled