feat(dashboard): add DashboardViewModel, metric gauge pager, chart integration

- Add DashboardScreenContract and DashboardViewModel with dummy data
- Extend MetricGauge with pager, page indicators, sensor config
- Integrate AirMQChart and city selector
- ManageScreen: scaffold contentWindowInsets for edge-to-edge header
- Add compose-foundation dependency for HorizontalPager

Made-with: Cursor

app/build.gradle.kts

@@ -81,6 +81,7 @@ dependencies {
     implementation(libs.androidx.compose.ui.graphics)
     implementation(libs.androidx.compose.ui.tooling.preview)
     implementation(libs.androidx.compose.material3)
+    implementation(libs.androidx.compose.foundation)
     implementation(libs.androidx.navigation.compose)
     implementation(libs.hilt.android)
     implementation(libs.androidx.hilt.navigation.compose)

app/src/main/kotlin/org/db3/airmq/features/common/chart/AirMQChart.kt

@@ -63,7 +63,7 @@ import java.text.SimpleDateFormat
 import java.util.Date
 import java.util.Locale
 
-private val ChartPaddingLeftDp = 56.dp
+private val ChartPaddingLeftDp = 40.dp
 private val ChartPaddingRightDp = 40.dp
 private val ChartPaddingTopDp = 8.dp
 private val ChartPaddingBottomDp = 52.dp

app/src/main/kotlin/org/db3/airmq/features/common/metric/MetricGauge.kt

@@ -13,9 +13,11 @@ import androidx.compose.foundation.shape.RoundedCornerShape
 import androidx.compose.material3.Icon
 import androidx.compose.material3.Text
 import androidx.compose.runtime.Composable
+import androidx.compose.runtime.LaunchedEffect
 import androidx.compose.runtime.remember
 import androidx.compose.ui.Alignment
 import androidx.compose.ui.Modifier
+import androidx.compose.foundation.shape.CircleShape
 import androidx.compose.ui.draw.clip
 import androidx.compose.ui.graphics.Color
 import androidx.compose.ui.res.painterResource
@@ -23,8 +25,15 @@ import androidx.compose.ui.text.font.FontWeight
 import androidx.compose.ui.tooling.preview.Preview
 import androidx.compose.ui.unit.dp
 import androidx.compose.ui.unit.sp
+import androidx.compose.foundation.ExperimentalFoundationApi
 import androidx.compose.foundation.layout.Arrangement
 import androidx.compose.foundation.layout.Row
+import androidx.compose.foundation.layout.Spacer
+import androidx.compose.foundation.layout.fillMaxWidth
+import androidx.compose.foundation.layout.height
+import androidx.compose.foundation.layout.width
+import androidx.compose.foundation.pager.HorizontalPager
+import androidx.compose.foundation.pager.rememberPagerState
 import org.db3.airmq.features.common.metric.getColorFromMetrics
 import org.db3.airmq.features.common.metric.getSensorIconRes
 import org.db3.airmq.ui.theme.AirMQTheme
@@ -126,21 +135,20 @@ fun MetricGauge(
     }
 }
 
-/** Default sensor order for dashboard gauge row. */
+/** Page 1: dust, radioactivity, temperature. */
-private val DashboardGaugeOrder = listOf(
+private val Page1Sensors = listOf(
     SensorType.DUST,
     SensorType.RADIOACTIVITY,
     SensorType.TEMPERATURE
 )
 
-/**
+/** Page 2: humidity, pressure. */
- * Horizontal row of metric gauges (dust, radioactivity, temperature).
+private val Page2Sensors = listOf(
- *
+    SensorType.HUMIDITY,
- * @param selectedSensor Currently selected sensor; null if none
+    SensorType.PRESSURE
- * @param values Map of sensor type to value
+)
- * @param onGaugeSelected Called when a gauge is tapped
+
- * @param modifier Modifier
+/** @deprecated Use MetricGaugePager. Kept for backward compatibility. */
- */
 @Composable
 fun MetricGaugeRow(
     selectedSensor: SensorType?,
@@ -152,7 +160,7 @@ fun MetricGaugeRow(
         modifier = modifier,
         horizontalArrangement = Arrangement.SpaceEvenly
     ) {
-        for (sensorType in DashboardGaugeOrder) {
+        for (sensorType in Page1Sensors) {
             MetricGauge(
                 value = values[sensorType],
                 sensorType = sensorType,
@@ -163,6 +171,90 @@ fun MetricGaugeRow(
     }
 }
 
+/**
+ * Paged metric gauges: 2 pages, 5 gauges total.
+ * Page 0: dust, radioactivity, temperature.
+ * Page 1: humidity, pressure.
+ *
+ * @param selectedSensor Currently selected sensor
+ * @param values Map of sensor type to value
+ * @param currentPage Current page index (0 or 1)
+ * @param onGaugeSelected Called when a gauge is tapped
+ * @param onPageChanged Called when page changes (e.g. after swipe)
+ * @param modifier Modifier
+ */
+@OptIn(ExperimentalFoundationApi::class)
+@Composable
+fun MetricGaugePager(
+    selectedSensor: SensorType,
+    values: Map<SensorType, Float?>,
+    currentPage: Int,
+    onGaugeSelected: (SensorType) -> Unit,
+    onPageChanged: (Int) -> Unit,
+    modifier: Modifier = Modifier
+) {
+    val pagerState = rememberPagerState(pageCount = { 2 })
+    LaunchedEffect(currentPage) {
+        if (pagerState.currentPage != currentPage) {
+            pagerState.animateScrollToPage(currentPage)
+        }
+    }
+    LaunchedEffect(pagerState.currentPage) {
+        onPageChanged(pagerState.currentPage)
+    }
+    Column(modifier = modifier) {
+        HorizontalPager(
+            state = pagerState,
+            modifier = Modifier.height(132.dp),
+            userScrollEnabled = true
+        ) { page ->
+            val sensors = if (page == 0) Page1Sensors else Page2Sensors
+            Row(
+                modifier = Modifier
+                    .fillMaxWidth()
+                    .padding(horizontal = 16.dp),
+                horizontalArrangement = Arrangement.SpaceEvenly
+            ) {
+                for (sensorType in sensors) {
+                    MetricGauge(
+                        value = values[sensorType],
+                        sensorType = sensorType,
+                        selected = selectedSensor == sensorType,
+                        onClick = { onGaugeSelected(sensorType) }
+                    )
+                }
+            }
+        }
+        Row(
+            modifier = Modifier
+                .fillMaxWidth()
+                .padding(top = 4.dp, bottom = 12.dp),
+            horizontalArrangement = Arrangement.Center,
+            verticalAlignment = Alignment.CenterVertically
+        ) {
+            PageIndicatorDot(selected = pagerState.currentPage == 0)
+            Spacer(modifier = Modifier.width(8.dp))
+            PageIndicatorDot(selected = pagerState.currentPage == 1)
+        }
+    }
+}
+
+@Composable
+private fun PageIndicatorDot(
+    selected: Boolean,
+    modifier: Modifier = Modifier
+) {
+    Box(
+        modifier = modifier
+            .size(8.dp)
+            .clip(CircleShape)
+            .background(
+                if (selected) Color.White
+                else Color.White.copy(alpha = 0.38f)
+            )
+    )
+}
+
 @Preview(showBackground = true, name = "Dust – value 6")
 @Composable
 private fun PreviewMetricGaugeDust() {
@@ -301,6 +393,36 @@ private fun PreviewMetricGaugeSelected() {
     }
 }
 
+@Preview(showBackground = true, name = "Gauge pager – page 1")
+@Composable
+private fun PreviewMetricGaugePager() {
+    AirMQTheme {
+        Box(
+            modifier = Modifier
+                .background(
+                    androidx.compose.ui.graphics.Brush.verticalGradient(
+                        colors = listOf(LegacyNavGradientStart, LegacyNavGradientEnd)
+                    )
+                )
+                .padding(16.dp)
+        ) {
+            MetricGaugePager(
+                selectedSensor = SensorType.DUST,
+                values = mapOf(
+                    SensorType.DUST to 6f,
+                    SensorType.RADIOACTIVITY to 0f,
+                    SensorType.TEMPERATURE to 3f,
+                    SensorType.HUMIDITY to 65f,
+                    SensorType.PRESSURE to 745f
+                ),
+                currentPage = 0,
+                onGaugeSelected = {},
+                onPageChanged = {}
+            )
+        }
+    }
+}
+
 @Preview(showBackground = true, name = "Gauge row")
 @Composable
 private fun PreviewMetricGaugeRow() {

app/src/main/kotlin/org/db3/airmq/features/dashboard/DashboardScreenContract.kt

@@ -0,0 +1,86 @@
+package org.db3.airmq.features.dashboard
+
+import androidx.compose.runtime.Composable
+import androidx.compose.ui.platform.LocalContext
+import org.db3.airmq.R
+import org.db3.airmq.features.common.chart.ChartConfig
+import org.db3.airmq.features.common.chart.ChartDataset
+import org.db3.airmq.features.common.chart.generateSineWaveData
+import org.db3.airmq.features.common.metric.SensorType
+import org.db3.airmq.ui.theme.ChartBackground
+import org.db3.airmq.ui.theme.ChartFill
+import androidx.compose.ui.graphics.Color
+
+object DashboardScreenContract {
+
+    @Composable
+    fun previewState(
+        city: String = "Minsk",
+        selectedSensor: SensorType = SensorType.DUST,
+        currentPage: Int = 0
+    ): State {
+        val chartData = when (selectedSensor) {
+            SensorType.DUST -> ChartDataset.Single(generateSineWaveData(amplitude = 8f, offset = 10f, periodCount = 1.5f))
+            SensorType.RADIOACTIVITY -> ChartDataset.Single(generateSineWaveData(amplitude = 0.15f, offset = 0.2f, periodCount = 1f))
+            SensorType.TEMPERATURE -> ChartDataset.Single(generateSineWaveData(amplitude = 5f, offset = 15f, periodCount = 2f))
+            SensorType.HUMIDITY -> ChartDataset.Single(generateSineWaveData(amplitude = 15f, offset = 55f, periodCount = 1.2f))
+            SensorType.PRESSURE -> ChartDataset.Single(generateSineWaveData(amplitude = 10f, offset = 740f, periodCount = 0.8f))
+            else -> ChartDataset.Single(generateSineWaveData())
+        }
+        val chartConfig = ChartConfig(
+            lineColor = Color.White,
+            fillColor = ChartFill,
+            backgroundColor = ChartBackground,
+            labelColor = Color.White,
+            leftTimeLabel = "Yesterday",
+            rightTimeLabel = "Now",
+            unit = selectedSensor.units(),
+            centerLabel = LocalContext.current.getString(
+                when (selectedSensor) {
+                    SensorType.DUST -> R.string.sensor_dust
+                    SensorType.RADIOACTIVITY -> R.string.sensor_radioactivity
+                    SensorType.TEMPERATURE -> R.string.sensor_temperature
+                    SensorType.HUMIDITY -> R.string.sensor_humidity
+                    SensorType.PRESSURE -> R.string.sensor_pressure
+                    else -> R.string.sensor_dust
+                }
+            )
+        )
+        return State(
+            city = city,
+            gaugeValues = mapOf(
+                SensorType.DUST to 6f,
+                SensorType.RADIOACTIVITY to 0f,
+                SensorType.TEMPERATURE to 3f,
+                SensorType.HUMIDITY to 65f,
+                SensorType.PRESSURE to 745f
+            ),
+            selectedSensor = selectedSensor,
+            currentPage = currentPage,
+            chartData = chartData,
+            chartConfig = chartConfig,
+            chartSensorLabel = chartConfig.centerLabel ?: ""
+        )
+    }
+
+    data class State(
+        val city: String,
+        val gaugeValues: Map<SensorType, Float?>,
+        val selectedSensor: SensorType,
+        val currentPage: Int,
+        val chartData: ChartDataset?,
+        val chartConfig: ChartConfig,
+        val chartSensorLabel: String
+    )
+
+    sealed interface Action {
+        data object OpenCity : Action
+        data object OpenNews : Action
+        data object OpenWidgetConstructor : Action
+    }
+
+    sealed interface Event {
+        data class GaugeSelected(val sensor: SensorType) : Event
+        data class PageChanged(val page: Int) : Event
+    }
+}

app/src/main/kotlin/org/db3/airmq/features/dashboard/DashboardViewModel.kt

@@ -0,0 +1,114 @@
+package org.db3.airmq.features.dashboard
+
+import android.content.Context
+import androidx.lifecycle.ViewModel
+import dagger.hilt.android.lifecycle.HiltViewModel
+import dagger.hilt.android.qualifiers.ApplicationContext
+import kotlinx.coroutines.flow.MutableSharedFlow
+import kotlinx.coroutines.flow.MutableStateFlow
+import kotlinx.coroutines.flow.SharedFlow
+import kotlinx.coroutines.flow.StateFlow
+import kotlinx.coroutines.flow.asSharedFlow
+import kotlinx.coroutines.flow.asStateFlow
+import kotlinx.coroutines.flow.update
+import javax.inject.Inject
+import org.db3.airmq.R
+import org.db3.airmq.features.common.chart.ChartConfig
+import org.db3.airmq.features.common.chart.ChartDataset
+import org.db3.airmq.features.common.chart.generateSineWaveData
+import org.db3.airmq.features.common.metric.SensorType
+import org.db3.airmq.ui.theme.ChartBackground
+import org.db3.airmq.ui.theme.ChartFill
+import androidx.compose.ui.graphics.Color
+
+@HiltViewModel
+class DashboardViewModel @Inject constructor(
+    @ApplicationContext private val context: Context
+) : ViewModel() {
+
+    private val _uiState = MutableStateFlow(initialState())
+    val uiState: StateFlow<DashboardScreenContract.State> = _uiState.asStateFlow()
+
+    private val _actions = MutableSharedFlow<DashboardScreenContract.Action>(extraBufferCapacity = 1)
+    val actions: SharedFlow<DashboardScreenContract.Action> = _actions.asSharedFlow()
+
+    fun onEvent(event: DashboardScreenContract.Event) {
+        when (event) {
+            is DashboardScreenContract.Event.GaugeSelected -> {
+                _uiState.update { state ->
+                    state.copy(
+                        selectedSensor = event.sensor,
+                        chartData = chartDataFor(event.sensor),
+                        chartConfig = chartConfigFor(event.sensor),
+                        chartSensorLabel = chartLabelFor(event.sensor)
+                    )
+                }
+            }
+            is DashboardScreenContract.Event.PageChanged -> {
+                _uiState.update { it.copy(currentPage = event.page) }
+            }
+        }
+    }
+
+    private fun initialState(): DashboardScreenContract.State {
+        val selected = SensorType.DUST
+        return DashboardScreenContract.State(
+            city = "Minsk",
+            gaugeValues = dummyGaugeValues(),
+            selectedSensor = selected,
+            currentPage = 0,
+            chartData = chartDataFor(selected),
+            chartConfig = chartConfigFor(selected),
+            chartSensorLabel = chartLabelFor(selected)
+        )
+    }
+
+    private fun dummyGaugeValues(): Map<SensorType, Float?> = mapOf(
+        SensorType.DUST to 6f,
+        SensorType.RADIOACTIVITY to 0f,
+        SensorType.TEMPERATURE to 3f,
+        SensorType.HUMIDITY to 65f,
+        SensorType.PRESSURE to 745f
+    )
+
+    private fun chartDataFor(sensor: SensorType): ChartDataset = when (sensor) {
+        SensorType.DUST -> ChartDataset.Single(
+            generateSineWaveData(amplitude = 8f, offset = 10f, periodCount = 1.5f)
+        )
+        SensorType.RADIOACTIVITY -> ChartDataset.Single(
+            generateSineWaveData(amplitude = 0.15f, offset = 0.2f, periodCount = 1f)
+        )
+        SensorType.TEMPERATURE -> ChartDataset.Single(
+            generateSineWaveData(amplitude = 5f, offset = 15f, periodCount = 2f)
+        )
+        SensorType.HUMIDITY -> ChartDataset.Single(
+            generateSineWaveData(amplitude = 15f, offset = 55f, periodCount = 1.2f)
+        )
+        SensorType.PRESSURE -> ChartDataset.Single(
+            generateSineWaveData(amplitude = 10f, offset = 740f, periodCount = 0.8f)
+        )
+        else -> ChartDataset.Single(generateSineWaveData())
+    }
+
+    private fun chartConfigFor(sensor: SensorType): ChartConfig = ChartConfig(
+        lineColor = Color.White,
+        fillColor = ChartFill,
+        backgroundColor = ChartBackground,
+        labelColor = Color.White,
+        leftTimeLabel = "Yesterday",
+        rightTimeLabel = "Now",
+        unit = sensor.units(),
+        centerLabel = chartLabelFor(sensor)
+    )
+
+    private fun chartLabelFor(sensor: SensorType): String = context.getString(
+        when (sensor) {
+            SensorType.DUST -> R.string.sensor_dust
+            SensorType.RADIOACTIVITY -> R.string.sensor_radioactivity
+            SensorType.TEMPERATURE -> R.string.sensor_temperature
+            SensorType.HUMIDITY -> R.string.sensor_humidity
+            SensorType.PRESSURE -> R.string.sensor_pressure
+            else -> R.string.sensor_dust
+        }
+    )
+}

app/src/main/kotlin/org/db3/airmq/features/manage/ManageScreen.kt

@@ -14,6 +14,7 @@ import androidx.compose.foundation.layout.height
 import androidx.compose.foundation.layout.padding
 import androidx.compose.foundation.layout.size
 import androidx.compose.foundation.layout.statusBarsPadding
+import androidx.compose.foundation.layout.WindowInsets
 import androidx.compose.foundation.layout.width
 import androidx.compose.foundation.lazy.LazyColumn
 import androidx.compose.foundation.lazy.items
@@ -85,7 +86,10 @@ private fun ManageScreenContent(
     uiState: State,
     onEvent: (Event) -> Unit
 ) {
-    Scaffold(modifier = Modifier.fillMaxSize()) { innerPadding ->
+    Scaffold(
+        modifier = Modifier.fillMaxSize(),
+        contentWindowInsets = WindowInsets(0, 0, 0, 0)
+    ) { innerPadding ->
         Column(
             modifier = Modifier
                 .fillMaxSize()

gradle/libs.versions.toml

@@ -44,6 +44,7 @@ androidx-compose-ui-tooling-preview = { group = "androidx.compose.ui", name = "u
 androidx-compose-ui-test-manifest = { group = "androidx.compose.ui", name = "ui-test-manifest" }
 androidx-compose-ui-test-junit4 = { group = "androidx.compose.ui", name = "ui-test-junit4" }
 androidx-compose-material3 = { group = "androidx.compose.material3", name = "material3" }
+androidx-compose-foundation = { group = "androidx.compose.foundation", name = "foundation" }
 androidx-navigation-compose = { group = "androidx.navigation", name = "navigation-compose", version.ref = "navigationCompose" }
 firebase-bom = { group = "com.google.firebase", name = "firebase-bom", version.ref = "firebaseBom" }
 firebase-analytics = { group = "com.google.firebase", name = "firebase-analytics" }