feat(map): grid QSO dialog Match button prefills the match page

- Grid-QSO dialog gains a Match action (radio-tower icon + label) in its
  header; tapping it navigates to the match page pre-filled with the tapped
  grid as the opposite station and a 24h time range, auto-starts the query,
  and scrolls the page straight to the time-range card.
- Every grid is now tappable (previously only worked grids opened the
  dialog); unworked grids show an empty QSO list instead of a hint.

app/src/main/java/com/rtbishop/look4sat/MainScreen.kt

@@ -244,7 +244,16 @@ fun MainScreen(
                             )
                         }
                         entry<Screen.Map> {
-                            MapDestination(mapFilterViewModel = mapFilterViewModel)
+                            MapDestination(
+                                mapFilterViewModel = mapFilterViewModel,
+                                onMatchGrid = { grid ->
+                                    // Grid-QSO dialog "Match" button: pre-fill the
+                                    // match page for that grid and switch to its tab.
+                                    mutualViewModel.prefillMatchFromGrid(grid)
+                                    while (backStack.size > 1) backStack.removeAt(backStack.size - 1)
+                                    backStack.add(Screen.Mutual)
+                                }
+                            )
                         }
                         entry<Screen.Mutual> {
                             MutualScreen(

core/presentation/src/main/res/values-zh/strings.xml

@@ -130,6 +130,7 @@
     <string name="grid_qso_count_many">%d QSOs</string>
     <string name="grid_qso_first">首通</string>
     <string name="grid_qso_no_sat">卫星未知</string>
+    <string name="grid_qso_match">匹配</string>
     <string name="map_visible">日照中</string>
 
     <!-- Settings screen -->

core/presentation/src/main/res/values/strings.xml

@@ -150,6 +150,7 @@
     <string name="grid_qso_count_many">%d QSOs</string>
     <string name="grid_qso_first">First</string>
     <string name="grid_qso_no_sat">satellite unknown</string>
+    <string name="grid_qso_match">Match</string>
     <string name="map_visible">Visible</string>
 
     <!-- Settings screen -->

feature/map/src/main/java/com/rtbishop/look4sat/feature/map/MapScreen.kt

@@ -31,10 +31,12 @@ import androidx.compose.foundation.layout.Box
 import androidx.compose.foundation.layout.Column
 import androidx.compose.foundation.layout.IntrinsicSize
 import androidx.compose.foundation.layout.Row
+import androidx.compose.foundation.layout.Spacer
 import androidx.compose.foundation.layout.fillMaxSize
 import androidx.compose.foundation.layout.fillMaxWidth
 import androidx.compose.foundation.layout.heightIn
 import androidx.compose.foundation.layout.padding
+import androidx.compose.foundation.layout.size
 import androidx.compose.foundation.layout.width
 import androidx.compose.foundation.lazy.LazyRow
 import androidx.compose.foundation.lazy.items
@@ -46,10 +48,12 @@ import androidx.compose.material3.CardDefaults
 import androidx.compose.material3.ElevatedCard
 import androidx.compose.material3.FilterChip
 import androidx.compose.material3.FilterChipDefaults
+import androidx.compose.material3.Icon
 import androidx.compose.material3.MaterialTheme
 import androidx.compose.material3.Surface
 import androidx.compose.material3.Switch
 import androidx.compose.material3.Text
+import androidx.compose.material3.TextButton
 import androidx.compose.runtime.Composable
 import androidx.compose.runtime.DisposableEffect
 import androidx.compose.runtime.LaunchedEffect
@@ -63,6 +67,7 @@ import androidx.compose.ui.draw.rotate
 import androidx.compose.ui.draw.scale
 import androidx.compose.ui.graphics.Color as ComposeColor
 import androidx.compose.ui.platform.LocalContext
+import androidx.compose.ui.res.painterResource
 import androidx.compose.ui.res.stringResource
 import androidx.compose.ui.unit.dp
 import androidx.compose.ui.unit.sp
@@ -145,7 +150,10 @@ private val moonIconPaint = Paint(Paint.ANTI_ALIAS_FLAG).apply {
 
 @Composable
 fun MapDestination(
-    mapFilterViewModel: MapFilterViewModel
+    mapFilterViewModel: MapFilterViewModel,
+    // Invoked with the tapped grid when the QSO dialog's "Match" button is
+    // pressed: navigate to the match page pre-filled for that grid.
+    onMatchGrid: (String) -> Unit = {}
 ) {
     val context = LocalContext.current
     val container = (context.applicationContext as IContainerProvider).getMainContainer()
@@ -182,7 +190,7 @@ fun MapDestination(
             viewModel.onAction(MapAction.SetVisible(false))
         }
     }
-    MapScreen(uiState, viewModel::onAction, mapView, mapFilterViewModel)
+    MapScreen(uiState, viewModel::onAction, mapView, mapFilterViewModel, onMatchGrid)
 }
 
 @Composable
@@ -190,7 +198,8 @@ private fun MapScreen(
     uiState: MapState,
     onAction: (MapAction) -> Unit,
     mapView: MapView,
-    mapFilterViewModel: MapFilterViewModel
+    mapFilterViewModel: MapFilterViewModel,
+    onMatchGrid: (String) -> Unit
 ) {
     val rotateMod = Modifier.rotate(180f)
     val timeString = uiState.mapData?.aosTime ?: "00:00:00"
@@ -261,7 +270,8 @@ private fun MapScreen(
                 // appear (GRID_ZOOM_SUB); grid labels now appear at that zoom too.
                 if (zoom < MaidenheadGridOverlay.GRID_ZOOM_SUB) return false
                 val grid = gridOfPoint(p.latitude, p.longitude) ?: return false
-                if (grid !in workedGrids) return false
+                // Every grid is tappable: worked grids show their confirmed QSOs,
+                // unworked grids open the same dialog with an empty list.
                 selectedGrid = grid
                 return true
             }
@@ -413,7 +423,8 @@ private fun MapScreen(
             grid = grid,
             qsos = uiState.workedGridQsos[grid].orEmpty().sortedBy { it.epochMs },
             isUtc = uiState.isUtc,
-            onDismiss = { selectedGrid = null }
+            onDismiss = { selectedGrid = null },
+            onMatch = { onMatchGrid(grid) }
         )
     }
 }
@@ -425,7 +436,8 @@ private fun WorkedGridQsoDialog(
     grid: String,
     qsos: List<com.rtbishop.look4sat.core.domain.model.GridQso>,
     isUtc: Boolean,
-    onDismiss: () -> Unit
+    onDismiss: () -> Unit,
+    onMatch: () -> Unit
 ) {
     androidx.compose.ui.window.Dialog(onDismissRequest = onDismiss) {
         // Centered card, ~85% width, internal scroll for long lists.
@@ -434,29 +446,43 @@ private fun WorkedGridQsoDialog(
             modifier = Modifier.fillMaxWidth(0.88f)
         ) {
             Column {
-                // Header: grid + counts
+                // Header: grid + counts on the left, "Match" action on the right
-                Column(Modifier.padding(horizontal = 16.dp, vertical = 10.dp)) {
+                // (jumps to the match page pre-filled with this grid).
-                    Text(
+                Row(
-                        text = grid,
+                    verticalAlignment = Alignment.CenterVertically,
-                        style = MaterialTheme.typography.titleLarge,
+                    modifier = Modifier.padding(start = 16.dp, end = 8.dp, top = 4.dp, bottom = 4.dp)
-                        color = MaterialTheme.colorScheme.primary,
+                ) {
-                        fontFamily = androidx.compose.ui.text.font.FontFamily.Monospace
+                    Column(Modifier.weight(1f)) {
-                    )
+                        Text(
-                    val distinctCalls = qsos.map { it.call }.distinct().size
+                            text = grid,
-                    Text(
+                            style = MaterialTheme.typography.titleLarge,
-                        text = stringResource(R.string.grid_qso_calls_count, distinctCalls, qsos.size),
+                            color = MaterialTheme.colorScheme.primary,
-                        style = MaterialTheme.typography.bodySmall,
+                            fontFamily = androidx.compose.ui.text.font.FontFamily.Monospace
-                        color = MaterialTheme.colorScheme.onSurfaceVariant
+                        )
-                    )
+                        val distinctCalls = qsos.map { it.call }.distinct().size
+                        Text(
+                            text = stringResource(R.string.grid_qso_calls_count, distinctCalls, qsos.size),
+                            style = MaterialTheme.typography.bodySmall,
+                            color = MaterialTheme.colorScheme.onSurfaceVariant
+                        )
+                    }
+                    TextButton(
+                        onClick = {
+                            onDismiss()
+                            onMatch()
+                        }
+                    ) {
+                        Icon(
+                            painter = painterResource(R.drawable.ic_radio_tower),
+                            contentDescription = null,
+                            modifier = Modifier.size(18.dp)
+                        )
+                        Spacer(Modifier.width(4.dp))
+                        Text(stringResource(R.string.grid_qso_match))
+                    }
                 }
                 androidx.compose.material3.HorizontalDivider()
-                if (qsos.isEmpty()) {
+                if (qsos.isNotEmpty()) {
-                    Text(
-                        text = stringResource(R.string.grid_qso_no_sat),
-                        style = MaterialTheme.typography.bodySmall,
-                        modifier = Modifier.padding(16.dp)
-                    )
-                } else {
                     // Group by callsign preserving first-contact order (list is
                     // already sorted oldest-first); expandable rows.
                     val grouped = remember(qsos) {

feature/mutual/src/main/java/com/rtbishop/look4sat/feature/mutual/MutualScreen.kt

@@ -246,7 +246,7 @@ private fun MutualContent(
         }
 
         // Input form
-        item {
+        item(key = "stationInputs") {
             Column(
                 modifier = Modifier.fillMaxWidth(),
                 verticalArrangement = Arrangement.spacedBy(6.dp)
@@ -323,16 +323,21 @@ private fun MutualContent(
                         )
                     }
                 }
-
-                MatchSearchCard(
-                    hoursAhead = state.hoursAhead,
-                    isCalculating = state.isCalculating,
-                    onHoursAhead = onHoursAhead,
-                    onQuery = onQuery
-                )
             }
         }
 
+        // Time range + query card. Its own LazyColumn item so a prefill from
+        // the map (grid-QSO dialog "Match" button) can scroll the page exactly
+        // to the time-range selector.
+        item(key = "matchSearch") {
+            MatchSearchCard(
+                hoursAhead = state.hoursAhead,
+                isCalculating = state.isCalculating,
+                onHoursAhead = onHoursAhead,
+                onQuery = onQuery
+            )
+        }
+
         // Results
         itemsIndexed(state.mutualPasses) { index, pass ->
             val mutualData = MutualPassData(
@@ -364,6 +369,17 @@ private fun MutualContent(
             )
         }
     }
+
+    // Prefill from the map's grid-QSO dialog "Match" button: jump straight to
+    // the time-range card. Index accounts for the optional error card at the
+    // top (error = 0, station inputs = 1, time range = 2; else 1).
+    val matchSearchIndex = if (state.errorMessage != null) 2 else 1
+    LaunchedEffect(state.scrollToTimeRange, matchSearchIndex) {
+        if (state.scrollToTimeRange) {
+            listState.scrollToItem(matchSearchIndex)
+            viewModel.consumeScrollToTimeRange()
+        }
+    }
 }
 
 @Composable

feature/mutual/src/main/java/com/rtbishop/look4sat/feature/mutual/MutualViewModel.kt

@@ -55,7 +55,11 @@ data class MutualUiState(
     val hasSearched: Boolean = false,
     val selectedPassIndex: Int = -1,
     val isUtc: Boolean = false,
-    val errorMessage: String? = null
+    val errorMessage: String? = null,
+    // One-shot flag set by prefillMatchFromGrid() (map grid → Match button):
+    // the page scrolls to the time-range card, then consumeScrollToTimeRange()
+    // clears it.
+    val scrollToTimeRange: Boolean = false
 )
 
 class MutualViewModel(
@@ -183,6 +187,32 @@ class MutualViewModel(
     fun onHoursAhead(value: Int) = _uiState.update { it.copy(hoursAhead = value) }
     fun onSelectPass(index: Int) = _uiState.update { it.copy(selectedPassIndex = index) }
 
+    /**
+     * Pre-fill the match page for a target grid picked from the map's grid-QSO
+     * dialog ("Match" button): set the opposite-station grid (with its
+     * coordinates), reset the time range to 24h, flag the page to scroll
+     * straight to the time-range card, and start the query immediately so
+     * results are ready when the page opens.
+     */
+    fun prefillMatchFromGrid(grid: String) {
+        val g = grid.trim().uppercase()
+        val pos = qthToPosition(g)
+        _uiState.update {
+            it.copy(
+                stationBGrid = g,
+                stationBLat = pos?.let { p -> "%.4f".format(p.latitude) } ?: it.stationBLat,
+                stationBLon = pos?.let { p -> "%.4f".format(p.longitude) } ?: it.stationBLon,
+                hoursAhead = 24,
+                scrollToTimeRange = true
+            )
+        }
+        queryMutualPasses()
+    }
+
+    fun consumeScrollToTimeRange() {
+        _uiState.update { it.copy(scrollToTimeRange = false) }
+    }
+
     fun queryMutualPasses() {
         val state = _uiState.value