From 2c6b35dbdf878b9f7666d2df9a1a255babb48467 Mon Sep 17 00:00:00 2001
From: andrekir <andrekir@pm.me>
Date: Sat, 8 Jul 2023 07:11:08 -0300
Subject: [PATCH] fix: revert zoomToNodes removal

revert https://github.com/meshtastic/Meshtastic-Android/pull/647/commits/4412a5d5aa6752c9bc1c71084c8570f6efea0df1
---
 .../com/geeksville/mesh/ui/map/MapFragment.kt  | 18 ++++++++++++++----
 .../com/geeksville/mesh/util/LocationUtils.kt  | 18 ++++++++++++++++++
 2 files changed, 32 insertions(+), 4 deletions(-)

diff --git a/app/src/main/java/com/geeksville/mesh/ui/map/MapFragment.kt b/app/src/main/java/com/geeksville/mesh/ui/map/MapFragment.kt
index 2da68ce52..ad969a502 100644
--- a/app/src/main/java/com/geeksville/mesh/ui/map/MapFragment.kt
+++ b/app/src/main/java/com/geeksville/mesh/ui/map/MapFragment.kt
@@ -50,11 +50,13 @@ import com.geeksville.mesh.ui.map.components.DownloadButton
 import com.geeksville.mesh.ui.map.components.EditWaypointDialog
 import com.geeksville.mesh.ui.map.components.MapStyleButton
 import com.geeksville.mesh.util.SqlTileWriterExt
+import com.geeksville.mesh.util.requiredZoomLevel
 import com.geeksville.mesh.util.formatAgo
 import com.geeksville.mesh.waypoint
 import com.google.accompanist.themeadapter.appcompat.AppCompatTheme
 import com.google.android.material.dialog.MaterialAlertDialogBuilder
 import dagger.hilt.android.AndroidEntryPoint
+import org.osmdroid.api.IMapController
 import org.osmdroid.config.Configuration
 import org.osmdroid.events.MapEventsReceiver
 import org.osmdroid.events.MapListener
@@ -111,6 +113,7 @@ fun MapView(model: UIViewModel = viewModel()) {
     // constants
     val defaultMinZoom = 1.5
     val defaultMaxZoom = 18.0
+    val defaultZoomSpeed = 3000L
     val prefsName = "org.geeksville.osm.prefs"
     val mapStyleId = "map_style_id"
     val nodeLayer = 1
@@ -432,6 +435,16 @@ fun MapView(model: UIViewModel = viewModel()) {
 //        }
 //    }
 
+    fun zoomToNodes(controller: IMapController) {
+        if (nodeMarkers.isNotEmpty()) {
+            val box = BoundingBox.fromGeoPoints(nodeMarkers.map { it.position })
+            val center = GeoPoint(box.centerLatitude, box.centerLongitude)
+            val maximumZoomLevel = map.tileProvider.tileSource.maximumZoomLevel.toDouble()
+            val finalZoomLevel = minOf(box.requiredZoomLevel() * 0.8, maximumZoomLevel)
+            controller.animateTo(center, finalZoomLevel, defaultZoomSpeed)
+        } else controller.zoomIn()
+    }
+
     fun loadOnlineTileSourceBase(): ITileSource {
         val id = mPrefs.getInt(mapStyleId, 1)
         debug("mapStyleId from prefs: $id")
@@ -577,10 +590,7 @@ fun MapView(model: UIViewModel = viewModel()) {
                     map.apply {
                         setTileSource(loadOnlineTileSourceBase())
                         defaultMapSettings()
-                        if (nodeMarkers.isNotEmpty()) zoomToBoundingBox(
-                            BoundingBox.fromGeoPoints(nodeMarkers.map { it.position }),
-                            false
-                        ) else controller.zoomIn()
+                        zoomToNodes(controller)
                     }
                 },
                 modifier = Modifier.fillMaxSize(),
diff --git a/app/src/main/java/com/geeksville/mesh/util/LocationUtils.kt b/app/src/main/java/com/geeksville/mesh/util/LocationUtils.kt
index 434f9d4de..9fe6ed9f8 100644
--- a/app/src/main/java/com/geeksville/mesh/util/LocationUtils.kt
+++ b/app/src/main/java/com/geeksville/mesh/util/LocationUtils.kt
@@ -5,10 +5,13 @@ import com.geeksville.mesh.Position
 import mil.nga.grid.features.Point
 import mil.nga.mgrs.MGRS
 import mil.nga.mgrs.utm.UTM
+import org.osmdroid.util.BoundingBox
+import org.osmdroid.util.GeoPoint
 import kotlin.math.abs
 import kotlin.math.acos
 import kotlin.math.atan2
 import kotlin.math.cos
+import kotlin.math.log2
 import kotlin.math.sin
 
 /*******************************************************************************
@@ -233,3 +236,18 @@ fun bearing(
 fun radToBearing(rad: Double): Double {
     return (Math.toDegrees(rad) + 360) % 360
 }
+
+/**
+ * Calculates the zoom level required to fit the entire [BoundingBox] inside the map view.
+ * @return The zoom level as a Double value.
+ */
+fun BoundingBox.requiredZoomLevel(): Double {
+    val topLeft = GeoPoint(this.latNorth, this.lonWest)
+    val bottomRight = GeoPoint(this.latSouth, this.lonEast)
+    val latLonWidth = topLeft.distanceToAsDouble(GeoPoint(topLeft.latitude, bottomRight.longitude))
+    val latLonHeight = topLeft.distanceToAsDouble(GeoPoint(bottomRight.latitude, topLeft.longitude))
+    val requiredLatZoom = log2(360.0 / (latLonHeight / 111320))
+    val requiredLonZoom = log2(360.0 / (latLonWidth / 111320))
+    return maxOf(requiredLatZoom, requiredLonZoom)
+}
+