Fixed crash when style is not fully loaded

lib/maplibre-compose/src/androidMain/kotlin/dev/sargunv/maplibrecompose/core/AndroidStyle.kt

@@ -18,6 +18,8 @@ import org.maplibre.android.style.sources.VectorSource as MLNVectorSource
 internal class AndroidStyle(style: MLNStyle) : Style {
   private var impl: MLNStyle = style
 
+  override var isLoaded: Boolean = true
+
   override fun addImage(id: String, image: ImageBitmap, sdf: Boolean) {
     impl.addImage(id, image.asAndroidBitmap(), sdf)
   }

lib/maplibre-compose/src/commonMain/kotlin/dev/sargunv/maplibrecompose/compose/MaplibreMap.kt

@@ -113,6 +113,9 @@ public fun MaplibreMap(
       object : MaplibreMap.Callbacks {
         override fun onStyleChanged(map: MaplibreMap, style: Style?) {
           map as StandardMaplibreMap
+
+          if (style == null) rememberedStyle?.isLoaded = false
+
           styleState.attach(style)
           rememberedStyle = style
           cameraState.metersPerDpAtTargetState.value =
@@ -133,6 +136,8 @@ public fun MaplibreMap(
         override fun onCameraMoveEnded(map: MaplibreMap) {}
 
         private fun layerNodesInOrder(): List<LayerNode<*>> {
+          if (styleComposition?.style?.isLoaded != true) return emptyList()
+
           val layerNodes =
             (styleComposition?.children?.filterIsInstance<LayerNode<*>>() ?: emptyList())
               .associateBy { node -> node.layer.id }

lib/maplibre-compose/src/commonMain/kotlin/dev/sargunv/maplibrecompose/compose/StyleState.kt

@@ -22,21 +22,26 @@ public class StyleState internal constructor() {
 
   public fun queryAttributionLinks(): List<AttributionLink> {
     // TODO expose this as State somehow?
-    return style?.getSources()?.flatMap { it.attributionLinks } ?: emptyList()
+    return getStyleIfLoaded()?.getSources()?.flatMap { it.attributionLinks } ?: emptyList()
   }
 
   /**
    * Retrieves all sources from the style.
    *
-   * @return A list of sources, or an empty list if the style is null or has no sources.
+   * @return A list of sources, or an empty list if the style is not fully loaded or has no sources.
    */
-  public fun getSources(): List<Source> = style?.getSources() ?: emptyList()
+  public fun getSources(): List<Source> = getStyleIfLoaded()?.getSources() ?: emptyList()
 
   /**
    * Retrieves a source by its [id].
    *
    * @param id The ID of the source to retrieve.
-   * @return The source with the specified ID, or null if no such source exists.
+   * @return The source with the specified ID, or null if no such source exists, or the style is not
+   *   fully loaded.
    */
-  public fun getSource(id: String): Source? = style?.getSource(id)
+  public fun getSource(id: String): Source? = getStyleIfLoaded()?.getSource(id)
+
+  private fun getStyleIfLoaded(): Style? {
+    return if (style?.isLoaded == true) style else null
+  }
 }

lib/maplibre-compose/src/commonMain/kotlin/dev/sargunv/maplibrecompose/compose/engine/ImageManager.kt

@@ -20,6 +20,8 @@ internal class ImageManager(private val node: StyleNode) {
   private val painterBitmaps = mutableMapOf<PainterKey, ImageBitmap>()
 
   internal fun acquireBitmap(key: BitmapKey): String {
+    if (!node.style.isLoaded) return ""
+
     bitmapCounter.increment(key) {
       val id = bitmapIds.addId(key)
       node.logger?.i { "Adding bitmap $id" }
@@ -29,6 +31,8 @@ internal class ImageManager(private val node: StyleNode) {
   }
 
   internal fun releaseBitmap(key: BitmapKey) {
+    if (!node.style.isLoaded) return
+
     bitmapCounter.decrement(key) {
       val id = bitmapIds.removeId(key)
       node.logger?.i { "Removing bitmap $id" }
@@ -50,6 +54,8 @@ internal class ImageManager(private val node: StyleNode) {
   }
 
   internal fun acquirePainter(key: PainterKey): String {
+    if (!node.style.isLoaded) return ""
+
     painterCounter.increment(key) {
       val id = painterIds.addId(key)
       node.logger?.i { "Adding painter $id" }
@@ -62,6 +68,8 @@ internal class ImageManager(private val node: StyleNode) {
   }
 
   internal fun releasePainter(key: PainterKey) {
+    if (!node.style.isLoaded) return
+
     painterCounter.decrement(key) {
       val id = painterIds.removeId(key)
       node.logger?.i { "Removing painter $id" }

lib/maplibre-compose/src/commonMain/kotlin/dev/sargunv/maplibrecompose/compose/engine/LayerManager.kt

@@ -4,7 +4,7 @@ import dev.sargunv.maplibrecompose.compose.layer.Anchor
 import dev.sargunv.maplibrecompose.core.layer.Layer
 
 internal class LayerManager(private val styleNode: StyleNode) {
-  private val baseLayers = styleNode.style.getLayers().associateBy { it.id }
+  private val baseLayers = getLayers().associateBy { it.id }
 
   private val userLayers = mutableListOf<LayerNode<*>>()
 
@@ -13,6 +13,8 @@ internal class LayerManager(private val styleNode: StyleNode) {
   private val replacementCounters = mutableMapOf<Anchor.Replace, Int>()
 
   internal fun addLayer(node: LayerNode<*>, index: Int) {
+    if (!styleNode.style.isLoaded) return
+
     require(node.layer.id !in baseLayers) {
       "Layer ID '${node.layer.id}' already exists in base style"
     }
@@ -24,6 +26,8 @@ internal class LayerManager(private val styleNode: StyleNode) {
   }
 
   internal fun removeLayer(node: LayerNode<*>, oldIndex: Int) {
+    if (!styleNode.style.isLoaded) return
+
     userLayers.removeAt(oldIndex)
 
     // special handling for Replace anchors
@@ -52,6 +56,8 @@ internal class LayerManager(private val styleNode: StyleNode) {
   }
 
   internal fun applyChanges() {
+    if (!styleNode.style.isLoaded) return
+
     val tailLayerIds = mutableMapOf<Anchor, String>()
     val missedLayers = mutableMapOf<Anchor, MutableList<LayerNode<*>>>()
 
@@ -132,4 +138,7 @@ internal class LayerManager(private val styleNode: StyleNode) {
         is Anchor.Replace -> layerId
         else -> null
       }
+
+  private fun getLayers() =
+    if (styleNode.style.isLoaded) styleNode.style.getLayers() else emptyList()
 }

lib/maplibre-compose/src/commonMain/kotlin/dev/sargunv/maplibrecompose/compose/engine/SourceManager.kt

@@ -4,7 +4,7 @@ import dev.sargunv.maplibrecompose.core.source.Source
 
 internal class SourceManager(private val node: StyleNode) {
 
-  private val baseSources = node.style.getSources().associateBy { it.id }
+  private val baseSources = getSources().associateBy { it.id }
   private val sourcesToAdd = mutableListOf<Source>()
   private val counter = ReferenceCounter<Source>()
 
@@ -13,6 +13,8 @@ internal class SourceManager(private val node: StyleNode) {
   }
 
   internal fun addReference(source: Source) {
+    if (!node.style.isLoaded) return
+
     require(source.id !in baseSources) { "Source ID '${source.id}' already exists in base style" }
     counter.increment(source) {
       node.logger?.i { "Queuing source ${source.id} for addition" }
@@ -21,6 +23,8 @@ internal class SourceManager(private val node: StyleNode) {
   }
 
   internal fun removeReference(source: Source) {
+    if (!node.style.isLoaded) return
+
     require(source.id !in baseSources) {
       "Source ID '${source.id}' is part of the base style and can't be removed here"
     }
@@ -31,11 +35,15 @@ internal class SourceManager(private val node: StyleNode) {
   }
 
   internal fun applyChanges() {
+    if (!node.style.isLoaded) return
+
     sourcesToAdd
       .onEach {
         node.logger?.i { "Adding source ${it.id}" }
         node.style.addSource(it)
       }
       .clear()
   }
+
+  private fun getSources() = if (node.style.isLoaded) node.style.getSources() else emptyList()
 }

lib/maplibre-compose/src/commonMain/kotlin/dev/sargunv/maplibrecompose/core/Style.kt

@@ -5,33 +5,53 @@ import dev.sargunv.maplibrecompose.core.layer.Layer
 import dev.sargunv.maplibrecompose.core.source.Source
 
 internal interface Style {
+  /**
+   * Returns true if the style is loaded. Returns false if a new style is underway of being loaded.
+   */
+  var isLoaded: Boolean
+
+  /** @throws IllegalStateException on Android if [isLoaded] is false. */
   fun addImage(id: String, image: ImageBitmap, sdf: Boolean)
 
+  /** @throws IllegalStateException on Android if [isLoaded] is false. */
   fun removeImage(id: String)
 
+  /** @throws IllegalStateException on Android if [isLoaded] is false. */
   fun getSource(id: String): Source?
 
+  /** @throws IllegalStateException on Android if [isLoaded] is false. */
   fun getSources(): List<Source>
 
+  /** @throws IllegalStateException on Android if [isLoaded] is false. */
   fun addSource(source: Source)
 
+  /** @throws IllegalStateException on Android if [isLoaded] is false. */
   fun removeSource(source: Source)
 
+  /** @throws IllegalStateException on Android if [isLoaded] is false. */
   fun getLayer(id: String): Layer?
 
+  /** @throws IllegalStateException on Android if [isLoaded] is false. */
   fun getLayers(): List<Layer>
 
+  /** @throws IllegalStateException on Android if [isLoaded] is false. */
   fun addLayer(layer: Layer)
 
+  /** @throws IllegalStateException on Android if [isLoaded] is false. */
   fun addLayerAbove(id: String, layer: Layer)
 
+  /** @throws IllegalStateException on Android if [isLoaded] is false. */
   fun addLayerBelow(id: String, layer: Layer)
 
+  /** @throws IllegalStateException on Android if [isLoaded] is false. */
   fun addLayerAt(index: Int, layer: Layer)
 
+  /** @throws IllegalStateException on Android if [isLoaded] is false. */
   fun removeLayer(layer: Layer)
 
   object Null : Style {
+    override var isLoaded: Boolean = false
+
     override fun addImage(id: String, image: ImageBitmap, sdf: Boolean) {}
 
     override fun removeImage(id: String) {}

lib/maplibre-compose/src/commonTest/kotlin/dev/sargunv/maplibrecompose/compose/FakeStyle.kt

@@ -15,6 +15,8 @@ internal class FakeStyle(
   private val layerList = layers.toMutableList()
   private val layerMap = layers.associateBy { it.id }.toMutableMap()
 
+  override var isLoaded: Boolean = true
+
   override fun addImage(id: String, image: ImageBitmap, sdf: Boolean) {
     if (id in imageMap) error("Image ID '${id}' already exists in style")
     imageMap[id] = image

lib/maplibre-compose/src/iosMain/kotlin/dev/sargunv/maplibrecompose/core/IosStyle.kt

@@ -19,6 +19,8 @@ import dev.sargunv.maplibrecompose.core.util.toUIImage
 internal class IosStyle(style: MLNStyle, private val getScale: () -> Float) : Style {
   private var impl: MLNStyle = style
 
+  override var isLoaded: Boolean = true
+
   override fun addImage(id: String, image: ImageBitmap, sdf: Boolean) {
     impl.setImage(image.toUIImage(getScale(), sdf), forName = id)
   }

lib/maplibre-compose/src/jsMain/kotlin/dev/sargunv/maplibrecompose/core/JsStyle.kt

@@ -7,6 +7,8 @@ import dev.sargunv.maplibrejs.Map as MlJsMap
 
 internal class JsStyle(internal val impl: MlJsMap) : Style {
 
+  override var isLoaded: Boolean = true
+
   override fun addImage(id: String, image: ImageBitmap, sdf: Boolean) {}
 
   override fun removeImage(id: String) {}