Improve isolate_trkseg feature by querying its endpoints for more.

app/src/main/java/net/voussoir/trkpt/Database.kt

@@ -85,11 +85,11 @@ class Database(val trackbook: Trackbook)
         connection.insert("trkpt", null, values)
     }
 
-    fun select_trkpt_start_end(device_id: String, start_time: Long, end_time: Long): Iterator<Trkpt>
+    fun select_trkpt_start_end(device_id: String, start_time: Long, end_time: Long, order: String="ASC"): Iterator<Trkpt>
     {
         Log.i("VOUSSOIR", "Track.trkpt_generator: Querying points between ${start_time} -- ${end_time}.")
         return _trkpt_generator(this.connection.rawQuery(
-            "SELECT device_id, lat, lon, time, provider, ele, accuracy, sat FROM trkpt WHERE device_id = ? AND time >= ? AND time <= ? ORDER BY time ASC",
+            "SELECT device_id, lat, lon, time, provider, ele, accuracy, sat FROM trkpt WHERE device_id = ? AND time >= ? AND time <= ? ORDER BY time ${order}",
             arrayOf(device_id, start_time.toString(), end_time.toString())
         ))
     }

app/src/main/java/net/voussoir/trkpt/Track.kt

@@ -36,10 +36,42 @@ data class Track (
     var name: String = "",
     var _start_time: Long = 0L,
     var _end_time: Long = 0L,
-    val trkpts: ArrayList<Trkpt> = ArrayList<Trkpt>(),
+    val trkpts: ArrayDeque<Trkpt> = ArrayDeque<Trkpt>(),
     var trackFormatVersion: Int = Keys.CURRENT_TRACK_FORMAT_VERSION,
 )
 {
+    /**
+     * Discover the true bounds of this trkseg by querying for points until the stop over threshold.
+     * This is extremely helpful when using the "when was I here" button on an area, then expanding
+     * the trkseg to its ends.
+     */
+    fun expand_to_trkseg_bounds()
+    {
+        if (trkpts.isEmpty())
+        {
+            return
+        }
+        var previous = trkpts.first()
+        for (trkpt in database.select_trkpt_start_end(device_id, start_time=0L, end_time=trkpts.first().time, order="DESC"))
+        {
+            if ((previous.time - trkpt.time) > Keys.STOP_OVER_THRESHOLD)
+            {
+                break
+            }
+            trkpts.addFirst(trkpt)
+            previous = trkpt
+        }
+        previous = trkpts.last()
+        for (trkpt in database.select_trkpt_start_end(device_id, start_time=trkpts.last().time, end_time=Long.MAX_VALUE, order="ASC"))
+        {
+            if ((trkpt.time - previous.time) > Keys.STOP_OVER_THRESHOLD)
+            {
+                break
+            }
+            trkpts.add(trkpt)
+            previous = trkpt
+        }
+    }
     fun export_gpx(context: Context, fileuri: Uri): Uri?
     {
         if (! database.ready)
@@ -133,7 +165,7 @@ data class Track (
 }
 
 data class TrackStatistics(
-    val trkpts: ArrayList<Trkpt>,
+    val trkpts: ArrayDeque<Trkpt>,
     var distance: Double = 0.0,
     var duration: Long = 0,
     var pause_duration: Long = 0,

app/src/main/java/net/voussoir/trkpt/TrackFragment.kt

@@ -311,6 +311,9 @@ class TrackFragment : Fragment(), MapListener, YesNoDialog.YesNoDialogListener
                         (polyline.actualPoints.first() as Trkpt).time,
                         (polyline.actualPoints.last() as Trkpt).time,
                     ))
+
+                    track.expand_to_trkseg_bounds()
+
                     set_datetimes_from_track()
                     render_track()
                 }
@@ -468,10 +471,7 @@ class TrackFragment : Fragment(), MapListener, YesNoDialog.YesNoDialogListener
                 delete_selected_trkpt_button.visibility = View.VISIBLE
                 use_trkpt_as_start_button.visibility = View.VISIBLE
                 use_trkpt_as_end_button.visibility = View.VISIBLE
-                if (track_segment_overlays.size > 1)
-                {
-                    isolate_trkseg_button.visibility = View.VISIBLE
-                }
+                isolate_trkseg_button.visibility = View.VISIBLE
                 return
             }
         })

app/src/main/java/net/voussoir/trkpt/Trkpt.kt

@@ -20,6 +20,7 @@ import android.location.Location
 import org.osmdroid.util.GeoPoint
 import org.osmdroid.views.overlay.Polyline
 import net.voussoir.trkpt.helpers.getNumberOfSatellites
+import net.voussoir.trkpt.helpers.iso8601_local
 
 class Trkpt(
     val device_id: String,
@@ -53,4 +54,9 @@ class Trkpt(
         location.time = this.time
         return location
     }
+
+    override fun toString(): String
+    {
+        return "${device_id} ${iso8601_local(time)} ${latitude}/${longitude}"
+    }
 }