From ff106ea1c9adf6ecef70dc96c883680836959817 Mon Sep 17 00:00:00 2001
From: Ahmed El-Helw <ahmedre@gmail.com>
Date: Wed, 2 Mar 2022 22:54:25 +0400
Subject: [PATCH] Fix incorrect ayah highlight during selection

---
 .../labs/androidquran/data/QuranDisplayData.kt    | 13 ++++---------
 .../labs/androidquran/data/SuraAyahIterator.kt    |  8 ++++++++
 .../quran/ayahtracker/AyahTrackerPresenter.kt     | 15 +++++++++------
 3 files changed, 21 insertions(+), 15 deletions(-)

diff --git a/app/src/main/java/com/quran/labs/androidquran/data/QuranDisplayData.kt b/app/src/main/java/com/quran/labs/androidquran/data/QuranDisplayData.kt
index 4d637f813e..f16f071456 100644
--- a/app/src/main/java/com/quran/labs/androidquran/data/QuranDisplayData.kt
+++ b/app/src/main/java/com/quran/labs/androidquran/data/QuranDisplayData.kt
@@ -173,17 +173,12 @@ class QuranDisplayData @Inject constructor(private val quranInfo: QuranInfo) {
     return context.getString(R.string.quran_sura_title, getSuraNameFromPage(context, page))
   }
 
-  fun getAyahKeysOnPage(page: Int, lowerBound: SuraAyah?, upperBound: SuraAyah?): Set<String> {
+  fun getAyahKeysOnPage(page: Int): Set<String> {
     val ayahKeys: MutableSet<String> = LinkedHashSet()
     val bounds = quranInfo.getPageBounds(page)
-    var start = SuraAyah(bounds[0], bounds[1])
-    var end = SuraAyah(bounds[2], bounds[3])
-    if (lowerBound != null) {
-      start = SuraAyah.max(start, lowerBound)
-    }
-    if (upperBound != null) {
-      end = SuraAyah.min(end, upperBound)
-    }
+    val start = SuraAyah(bounds[0], bounds[1])
+    val end = SuraAyah(bounds[2], bounds[3])
+
     val iterator = SuraAyahIterator(quranInfo, start, end)
     while (iterator.next()) {
       ayahKeys.add(iterator.sura.toString() + ":" + iterator.ayah.toString())
diff --git a/app/src/main/java/com/quran/labs/androidquran/data/SuraAyahIterator.kt b/app/src/main/java/com/quran/labs/androidquran/data/SuraAyahIterator.kt
index 0508d019b3..dbb8622ff8 100644
--- a/app/src/main/java/com/quran/labs/androidquran/data/SuraAyahIterator.kt
+++ b/app/src/main/java/com/quran/labs/androidquran/data/SuraAyahIterator.kt
@@ -54,4 +54,12 @@ class SuraAyahIterator(
     }
     return true
   }
+
+  fun asSet(): Set<String> {
+    val suraAyahSet = mutableSetOf<String>()
+    while (next()) {
+      suraAyahSet.add("$sura:$ayah")
+    }
+    return suraAyahSet
+  }
 }
diff --git a/app/src/main/java/com/quran/labs/androidquran/presenter/quran/ayahtracker/AyahTrackerPresenter.kt b/app/src/main/java/com/quran/labs/androidquran/presenter/quran/ayahtracker/AyahTrackerPresenter.kt
index 5f96dba044..115c1d33e5 100644
--- a/app/src/main/java/com/quran/labs/androidquran/presenter/quran/ayahtracker/AyahTrackerPresenter.kt
+++ b/app/src/main/java/com/quran/labs/androidquran/presenter/quran/ayahtracker/AyahTrackerPresenter.kt
@@ -17,6 +17,7 @@ import com.quran.data.model.selection.startSuraAyah
 import com.quran.labs.androidquran.common.LocalTranslation
 import com.quran.labs.androidquran.common.QuranAyahInfo
 import com.quran.labs.androidquran.data.QuranDisplayData
+import com.quran.labs.androidquran.data.SuraAyahIterator
 import com.quran.labs.androidquran.presenter.Presenter
 import com.quran.labs.androidquran.presenter.quran.ayahtracker.AyahTrackerPresenter.AyahInteractionHandler
 import com.quran.labs.androidquran.ui.PagerActivity
@@ -111,13 +112,15 @@ class AyahTrackerPresenter @Inject constructor(
         highlightAyah(suraAyah.sura, suraAyah.ayah, -1, HighlightTypes.SELECTION, false)
       }
       is AyahSelection.AyahRange -> {
+        val highlightAyatIterator =
+          SuraAyahIterator(quranInfo, ayahSelection.startSuraAyah, ayahSelection.endSuraAyah)
+        val highlightedAyat = highlightAyatIterator.asSet()
         items.forEach {
-          val elements = quranDisplayData.getAyahKeysOnPage(
-            it.page,
-            ayahSelection.startSuraAyah,
-            ayahSelection.endSuraAyah
-          )
-          it.onHighlightAyat(it.page, elements, HighlightTypes.SELECTION)
+          val pageAyat = quranDisplayData.getAyahKeysOnPage(it.page)
+          val elements = pageAyat.intersect(highlightedAyat)
+          if (elements.isNotEmpty()) {
+            it.onHighlightAyat(it.page, elements, HighlightTypes.SELECTION)
+          }
         }
       }
       else -> { /* nothing is selected, and we already cleared */ }