fix ANR

app/src/main/java/org/pupes/mhdrunpathfinder/MainActivity.kt

@@ -50,8 +50,14 @@ import java.io.File
 import java.io.FileInputStream
 import java.io.FileOutputStream
 import java.net.URL
+import kotlinx.coroutines.*
+import java.util.concurrent.Executors
+import android.os.StrictMode
 
 
+// Thread pool for tile downloading to prevent blocking UI thread
+private val tileDownloadExecutor = Executors.newFixedThreadPool(4)
+
 // MapState configuration for OpenStreetMap
 // Max zoom level is 18, tile size is 256x256
 // At zoom level 18, there are 2^18 = 262144 tiles in each dimension
@@ -67,6 +73,7 @@ val mapState = MapState(
  * Creates a cached tile stream provider for OpenStreetMap tiles
  * Tiles are cached in the app's cache directory for offline access and faster loading
  * Cache expires after 30 days to ensure map updates are fetched
+ * Uses background thread pool to prevent ANR (Application Not Responding)
  */
 fun createCachedTileStreamProvider(context: Context, cacheExpiryDays: Int = 30): TileStreamProvider {
     val cacheDir = File(context.cacheDir, "map_tiles")
@@ -89,12 +96,16 @@ fun createCachedTileStreamProvider(context: Context, cacheExpiryDays: Int = 30):
                 // Use cached tile
                 FileInputStream(tileFile)
             } else {
-                // Download tile from OpenStreetMap (either new or expired)
+                // Download tile from OpenStreetMap in background thread
+                val future = tileDownloadExecutor.submit<FileInputStream?> {
+                    try {
                         val url = URL("https://tile.openstreetmap.org/$zoomLvl/$col/$row.png")
                         val connection = url.openConnection()
                         // Set User-Agent header as required by OSM tile usage policy
                         val userAgent = "${BuildConfig.APPLICATION_ID}/${BuildConfig.VERSION_NAME} (Android) (Contact: poliecho@pupes.org)"
                         connection.setRequestProperty("User-Agent", userAgent)
+                        connection.connectTimeout = 5000 // 5 second timeout
+                        connection.readTimeout = 10000 // 10 second timeout
 
                         val inputStream = connection.getInputStream()
 
@@ -108,23 +119,36 @@ fun createCachedTileStreamProvider(context: Context, cacheExpiryDays: Int = 30):
 
                         // Return the cached file's input stream
                         FileInputStream(tileFile)
+                    } catch (e: Exception) {
+                        e.printStackTrace()
+                        null
+                    }
+                }
+
+                // Wait for download with timeout
+                try {
+                    future.get() ?: run {
+                        // If download failed but we have a cached tile (even if expired), use it
+                        if (tileFile.exists()) {
+                            FileInputStream(tileFile)
+                        } else {
+                            null
+                        }
                     }
                 } catch (e: Exception) {
-            // If download fails but we have a cached tile (even if expired), use it
-            val tileFile = File(cacheDir, "tile_${zoomLvl}_${col}_${row}.png")
+                    // If download timed out or failed, try using expired cache
                     if (tileFile.exists()) {
-                try {
                         FileInputStream(tileFile)
-                } catch (fallbackError: Exception) {
-                    e.printStackTrace()
-                    null
-                }
                     } else {
-                e.printStackTrace()
                         null
                     }
                 }
             }
+        } catch (e: Exception) {
+            e.printStackTrace()
+            null
+        }
+    }
 }
 
 
@@ -132,6 +156,21 @@ class MainActivity : ComponentActivity() {
     override fun onCreate(savedInstanceState: Bundle?) {
         super.onCreate(savedInstanceState)
 
+        // Configure StrictMode to detect threading violations (debug mode only)
+        if (BuildConfig.DEBUG) {
+            StrictMode.setThreadPolicy(
+                StrictMode.ThreadPolicy.Builder()
+                    .detectAll()
+                    .penaltyLog()  // Log violations instead of crashing
+                    .build()
+            )
+            StrictMode.setVmPolicy(
+                StrictMode.VmPolicy.Builder()
+                    .detectAll()
+                    .penaltyLog()
+                    .build()
+            )
+        }
 
         setContent {
             MaterialTheme {