Group overdue tasks together

app/src/main/java/org/tasks/tasklist/AdapterSection.kt

@@ -18,7 +18,7 @@ data class AdapterSection(
 ) {
     fun headerColor(context: Context, sortMode: Int, textColor: Int = R.color.text_secondary) =
             ContextCompat.getColor(context, if ((sortMode == SORT_DUE || sortMode == SORT_START)
-                    && value > 0
+                    && (value > 0 || value == -1L)
                     && value.toDateTime().plusDays(1).startOfDay().isBeforeNow) {
                 R.color.overdue
             } else {
@@ -35,6 +35,7 @@ data class AdapterSection(
     ): String =
             when {
                 sortMode == SORT_IMPORTANCE -> context.getString(priorityToString())
+                value == -1L -> context.getString(R.string.filter_overdue)
                 value == 0L -> context.getString(when (sortMode) {
                     SORT_DUE -> R.string.no_due_date
                     SORT_START -> R.string.no_start_date

app/src/main/java/org/tasks/tasklist/SectionedDataSource.kt

@@ -2,9 +2,9 @@ package org.tasks.tasklist
 
 import android.util.SparseArray
 import androidx.core.util.forEach
+import com.todoroo.andlib.utility.DateUtilities.now
 import com.todoroo.astrid.core.SortHelper
 import org.tasks.data.TaskContainer
-import org.tasks.date.DateTimeUtils
 import org.tasks.time.DateTimeUtils.startOfDay
 import java.util.*
 
@@ -58,11 +58,18 @@ class SectionedDataSource constructor(
 
     private fun getSections(): SparseArray<AdapterSection> {
         val sections = ArrayList<AdapterSection>()
+        val startOfToday = now().startOfDay()
         for (i in tasks.indices) {
             val task = tasks[i]
             val sortGroup = task.sortGroup ?: continue
             val header = if (sortMode == SortHelper.SORT_IMPORTANCE || sortGroup == 0L) {
                 sortGroup
+            } else if (sortMode == SortHelper.SORT_DUE) {
+                when {
+                    sortGroup == 0L -> 0
+                    sortGroup < startOfToday -> -1
+                    else -> sortGroup.startOfDay()
+                }
             } else {
                 sortGroup.startOfDay()
             }
@@ -75,7 +82,17 @@ class SectionedDataSource constructor(
                     SortHelper.SORT_IMPORTANCE -> if (header != previous) {
                         sections.add(AdapterSection(i, header, 0, isCollapsed))
                     }
-                    else -> if (previous > 0 && header != DateTimeUtils.newDateTime(previous).startOfDay().millis) {
+                    SortHelper.SORT_DUE -> {
+                        val previousOverdue = previous < startOfToday
+                        val currentOverdue = header == -1L
+                        if (previous > 0 &&
+                            ((currentOverdue != previousOverdue) ||
+                                    (!currentOverdue && header != previous.startOfDay()))
+                        ) {
+                            sections.add(AdapterSection(i, header, 0, isCollapsed))
+                        }
+                    }
+                    else -> if (previous > 0 && header != previous.startOfDay()) {
                         sections.add(AdapterSection(i, header, 0, isCollapsed))
                     }
                 }

app/src/main/java/org/tasks/tasklist/TaskViewHolder.kt

@@ -10,6 +10,7 @@ import android.widget.TextView
 import androidx.recyclerview.widget.RecyclerView
 import com.google.android.material.chip.ChipGroup
 import com.todoroo.andlib.utility.DateUtilities
+import com.todoroo.andlib.utility.DateUtilities.now
 import com.todoroo.astrid.api.Filter
 import com.todoroo.astrid.core.SortHelper.SORT_DUE
 import com.todoroo.astrid.core.SortHelper.SORT_START
@@ -193,8 +194,9 @@ class TaskViewHolder internal constructor(
                 dueDate.setTextColor(textColorSecondary)
             }
             val dateValue: String? = if (sortByDueDate
-                    && task.sortGroup?.startOfDay() == task.dueDate.startOfDay()
-                    && preferences.showGroupHeaders()) {
+                    && task.sortGroup >= now().startOfDay()
+                    && preferences.showGroupHeaders()
+            ) {
                 task.takeIf { it.hasDueTime() }?.let {
                     DateUtilities.getTimeString(context, newDateTime(task.dueDate))
                 }