Fixes Issue 5933: Nearby: Display of all nearby pins makes the app sluggish, leads to crashes (#6181)

* Place.java: change getWikiDataEntityID() method to increase speed

Before this commit, this method would perform the String replace method on the Wikidata link every time
getWikiDataEntityID() was called. Also, getWikiDataLink() was called. This caused poor performance
since both method calls are slow.

This commit changes the method to only run the slow methods if the entityID field is empty or
null. Once the field is populated, the method simply returns the field. This change allows
getWikiDataEntityID() to run much faster.

* NearbyParentFragmentPresenter.kt: change async and place update parameters

Before this commit, the parameters that configure the async and place update code contributed to
the slow loading of the red and green map markers.

This commit changes the parameters such that the red and green map markers load much faster.

These parameters may need further tuning. This commit's changes are simply an educated
guess at a good parameter set.

* NearbyParentFragment.kt: rewrite Java Drawable caching code to Kotlin

Before this commit, the code which cached Drawables was written in Java.

This commit rewrites that code into the new Kotlin file, which replaces the Java file.

* NearbyParentFragmentPresenter.kt: change loadPlacesDataAsync to retry HTTP requests after failure

Before this commit, when an HTTP request failed, the entire batch of Places would not get updated,
even if it was only one Place in the batch that caused the failure.

This commit changes the code such that upon HTTP request failure, new HTTP requests are sent with
one Place per request. This allows more Places to be fetched from the server.

app/src/main/java/fr/free/nrw/commons/nearby/Place.java

@@ -232,13 +232,23 @@ public class Place implements Parcelable {
      */
     @Nullable
     public String getWikiDataEntityId() {
+        if (this.entityID != null && !this.entityID.equals("")) {
+            return this.entityID;
+        }
+
         if (!hasWikidataLink()) {
             Timber.d("Wikidata entity ID is null for place with sitelink %s", siteLinks.toString());
             return null;
         }
 
+        //Determine entityID from link
         String wikiDataLink = siteLinks.getWikidataLink().toString();
-        return wikiDataLink.replace("http://www.wikidata.org/entity/", "");
+
+        if (wikiDataLink.contains("http://www.wikidata.org/entity/")) {
+            this.entityID = wikiDataLink.substring("http://www.wikidata.org/entity/".length());
+            return this.entityID;
+        }
+        return null;
     }
 
     /**

app/src/main/java/fr/free/nrw/commons/nearby/fragments/NearbyParentFragment.kt

@@ -11,6 +11,7 @@ import android.content.IntentFilter
 import android.content.res.Configuration
 import android.graphics.Color
 import android.graphics.Paint
+import android.graphics.drawable.Drawable
 import android.location.Location
 import android.location.LocationManager
 import android.net.Uri
@@ -219,6 +220,7 @@ class NearbyParentFragment : CommonsDaggerSupportFragment(), NearbyParentFragmen
 
     @Volatile
     private var stopQuery = false
+    private var drawableCache: MutableMap<Pair<Context, Int>, Drawable>? = null
 
     // Explore map data (for if we came from Explore)
     private var prevZoom = 0.0
@@ -721,6 +723,7 @@ class NearbyParentFragment : CommonsDaggerSupportFragment(), NearbyParentFragmen
                 startMapWithoutPermission()
             }
         }
+        drawableCache = HashMap()
     }
 
     /**
@@ -1501,7 +1504,7 @@ class NearbyParentFragment : CommonsDaggerSupportFragment(), NearbyParentFragmen
                         marker.showInfoWindow()
                         presenter!!.handlePinClicked(updatedPlace)
                         savePlaceToDatabase(place)
-                        val icon = ContextCompat.getDrawable(
+                        val icon = getDrawable(
                             requireContext(),
                             getIconFor(updatedPlace, isBookMarked)
                         )
@@ -2027,8 +2030,35 @@ class NearbyParentFragment : CommonsDaggerSupportFragment(), NearbyParentFragmen
             )
     }
 
+    /**
+     * Gets the specified Drawable object. This is a wrapper method for ContextCompat.getDrawable().
+     * This method caches results from previous calls for faster retrieval.
+     *
+     * @param context The context to use to get the Drawable
+     * @param id The integer that describes the Drawable resource
+     * @return The Drawable object
+     */
+    private fun getDrawable(context: Context?, id: Int?): Drawable? {
+        if (drawableCache == null || context == null || id == null) {
+            return null
+        }
+
+        val key = Pair(context, id)
+        if (!drawableCache!!.containsKey(key)) {
+            val drawable = ContextCompat.getDrawable(context, id)
+
+            if (drawable != null) {
+                drawableCache!![key] = drawable
+            } else {
+                return null
+            }
+        }
+
+        return drawableCache!![key]
+    }
+
     fun convertToMarker(place: Place, isBookMarked: Boolean): Marker {
-        val icon = ContextCompat.getDrawable(requireContext(), getIconFor(place, isBookMarked))
+        val icon = getDrawable(requireContext(), getIconFor(place, isBookMarked))
         val point = GeoPoint(place.location.latitude, place.location.longitude)
         val marker = Marker(binding!!.map)
         marker.position = point
@@ -2430,7 +2460,7 @@ class NearbyParentFragment : CommonsDaggerSupportFragment(), NearbyParentFragmen
                 Marker.ANCHOR_BOTTOM
             )
             startMarker.icon =
-                ContextCompat.getDrawable(
+                getDrawable(
                     this.requireContext(),
                     fr.free.nrw.commons.R.drawable.current_location_marker
                 )
@@ -2488,7 +2518,7 @@ class NearbyParentFragment : CommonsDaggerSupportFragment(), NearbyParentFragmen
             Marker(binding?.map).apply {
                 position = it
                 setAnchor(Marker.ANCHOR_CENTER, Marker.ANCHOR_BOTTOM)
-                icon = ContextCompat.getDrawable(context, R.drawable.current_location_marker)
+                icon = getDrawable(context, R.drawable.current_location_marker)
                 title = "Your Location"
                 textLabelFontSize = 24
                 overlays.add(this)

app/src/main/java/fr/free/nrw/commons/nearby/presenter/NearbyParentFragmentPresenter.kt

@@ -25,9 +25,12 @@ import kotlinx.coroutines.Job
 import kotlinx.coroutines.channels.Channel
 import kotlinx.coroutines.delay
 import kotlinx.coroutines.ensureActive
+import kotlinx.coroutines.job
 import kotlinx.coroutines.launch
 import kotlinx.coroutines.withContext
+import okhttp3.internal.wait
 import timber.log.Timber
+import java.io.IOException
 import java.lang.reflect.InvocationHandler
 import java.lang.reflect.Method
 import java.lang.reflect.Proxy
@@ -75,8 +78,8 @@ class NearbyParentFragmentPresenter
      * - **connnectionCount**: number of parallel requests
      */
     private object LoadPlacesAsyncOptions {
-        const val BATCH_SIZE = 3
+        const val BATCH_SIZE = 10
-        const val CONNECTION_COUNT = 3
+        const val CONNECTION_COUNT = 20
     }
 
     private var schedulePlacesUpdateJob: Job? = null
@@ -91,7 +94,7 @@ class NearbyParentFragmentPresenter
     private object SchedulePlacesUpdateOptions {
         var skippedCount = 0
         const val SKIP_LIMIT = 3
-        const val SKIP_DELAY_MS = 500L
+        const val SKIP_DELAY_MS = 100L
     }
 
     // used to tell the asynchronous place detail loading job that the places' bookmarked status
@@ -379,13 +382,32 @@ class NearbyParentFragmentPresenter
                             )
                         } catch (e: Exception) {
                             Timber.tag("NearbyPinDetails").e(e)
-                            collectResults.send(indices.map { Pair(it, updatedGroups[it]) })
+                            //HTTP request failed. Try individual places
+                            for (i in indices) {
+                                launch {
+                                    val onePlaceBatch = mutableListOf<Pair<Int, MarkerPlaceGroup>>()
+                                    try {
+                                        val fetchedPlace = nearbyController.getPlaces(
+                                            mutableListOf(updatedGroups[i].place)
+                                        )
+
+                                        onePlaceBatch.add(Pair(i, MarkerPlaceGroup(
+                                            bookmarkLocationDao.findBookmarkLocation(
+                                                fetchedPlace[0]),fetchedPlace[0])))
+                                    } catch (e: Exception) {
+                                        Timber.tag("NearbyPinDetails").e(e)
+                                        onePlaceBatch.add(Pair(i, updatedGroups[i]))
+                                    }
+                                    collectResults.send(onePlaceBatch)
+                                }
+                            }
                         }
                     }
                 }
             }
             var collectCount = 0
-            for (resultList in collectResults) {
+            while (collectCount < indicesToUpdate.size) {
+                val resultList = collectResults.receive()
                 for ((index, fetchedPlaceGroup) in resultList) {
                     val existingPlace = updatedGroups[index].place
                     val finalPlaceGroup = MarkerPlaceGroup(
@@ -442,9 +464,7 @@ class NearbyParentFragmentPresenter
                     }
                 }
                 schedulePlacesUpdate(updatedGroups)
-                if (++collectCount == totalBatches) {
+                collectCount += resultList.size
-                    break
-                }
             }
             collectResults.close()
         }