Fix image deselection issue in ImageAdapter to update UI correctly (#6409)

app/src/main/java/fr/free/nrw/commons/customselector/ui/adapter/ImageAdapter.kt

@@ -165,13 +165,8 @@ class ImageAdapter(
             val selectedIndex: Int =
                 if (showAlreadyActionedImages) {
                     ImageHelper.getIndex(selectedImages, image)
-
-                    // Getting selected index when switch is off
                 } else if (actionableImagesMap.size > position) {
-                    ImageHelper
+                    ImageHelper.getIndex(selectedImages, ArrayList(actionableImagesMap.values)[position])
-                        .getIndex(selectedImages, ArrayList(actionableImagesMap.values)[position])
-
-                    // For any other case return -1
                 } else {
                     -1
                 }
@@ -204,8 +199,6 @@ class ImageAdapter(
                             uploadingContributionList
                         )
                         _isLoadingImages.value = false
-                        // If the position is already visited, that means the image is already present
-                        // inside map, so it will fetch the image from the map and load in the holder
                     } else {
                         val actionableImages: List<Image> = ArrayList(actionableImagesMap.values)
                         if (actionableImages.size > position) {
@@ -217,9 +210,6 @@ class ImageAdapter(
                                 .into(holder.image)
                         }
                     }
-
-                    // If switch is turned off, it just fetches the image from all images without any
-                    // further operations
                 } else {
                     Glide
                         .with(holder.image)
@@ -263,10 +253,6 @@ class ImageAdapter(
         // finding next actionable image will start from this position
         if (next > -1) {
             nextImagePosition = next + 1
-
-            // If map doesn't contains the next actionable image, that means it's a
-            // new actionable image, it will put it to the map as actionable images
-            // and it will load the new image in the view holder
             if (!actionableImagesMap.containsKey(next)) {
                 actionableImagesMap[next] = allImages[next]
                 alreadyAddedPositions.add(imagePositionAsPerIncreasingOrder)
@@ -280,9 +266,6 @@ class ImageAdapter(
                 notifyItemInserted(position)
                 notifyItemRangeChanged(position, itemCount + 1)
             }
-
-            // If next actionable image is not found, that means searching is
-            // complete till end, and it will stop searching.
         } else {
             reachedEndOfFolder = true
             notifyItemRemoved(position)
@@ -296,14 +279,39 @@ class ImageAdapter(
     private fun onThumbnailClicked(
         position: Int,
         holder: ImageViewHolder,
+    ) {
+        val sharedPreferences: SharedPreferences =
+            context.getSharedPreferences(CUSTOM_SELECTOR_PREFERENCE_KEY, 0)
+        val switchState =
+            sharedPreferences.getBoolean(SHOW_ALREADY_ACTIONED_IMAGES_PREFERENCE_KEY, true)
+
+        // While switch is turned off, lets user click on image only if the position is
+        // added inside map
+        if (!switchState) {
+            if (actionableImagesMap.size > position) {
+                selectOrRemoveImage(holder, position)
+            }
+        } else {
+            selectOrRemoveImage(holder, position)
+        }
+    }
+
+    /**
+     * Handle click event on an image, update counter on images.
+     */
+    private fun selectOrRemoveImage(
+        holder: ImageViewHolder,
+        position: Int,
     ) {
         val sharedPreferences: SharedPreferences =
             context.getSharedPreferences(CUSTOM_SELECTOR_PREFERENCE_KEY, 0)
         val showAlreadyActionedImages =
             sharedPreferences.getBoolean(SHOW_ALREADY_ACTIONED_IMAGES_PREFERENCE_KEY, true)
 
-        // Single Selection mode
+        // Getting clicked index from all images index when show_already_actioned_images
+        // switch is on
         if (singleSelection) {
+            // If single selection mode, clear previous selection and select only the new one
             if (selectedImages.isNotEmpty() && (selectedImages[0] != images[position])) {
                 val prevIndex = images.indexOf(selectedImages[0])
                 selectedImages.clear()
@@ -323,7 +331,8 @@ class ImageAdapter(
                 numberOfSelectedImagesMarkedAsNotForUpload--
             }
             notifyItemChanged(position, ImageUnselected())
-            imageSelectListener.onSelectedImagesChanged(selectedImages, numberOfSelectedImagesMarkedAsNotForUpload)  // Added this line to notify the activity
+            // Notify listener of deselection to update UI
+            imageSelectListener.onSelectedImagesChanged(selectedImages, numberOfSelectedImagesMarkedAsNotForUpload)
         } else {
             val image = images[position]
             scope.launch(ioDispatcher) {
@@ -349,7 +358,6 @@ class ImageAdapter(
                     }
                     selectedImages.add(image)
                     notifyItemChanged(position, ImageSelectedOrUpdated())
-
                     imageSelectListener.onSelectedImagesChanged(selectedImages, numberOfSelectedImagesMarkedAsNotForUpload)
                 }
             }
@@ -431,7 +439,6 @@ class ImageAdapter(
         } else {
             val iterator = actionableImagesMap.entries.iterator()
             var index = 0
-
             while (iterator.hasNext()) {
                 val entry = iterator.next()
                 if (entry.value == image) {
@@ -459,17 +466,10 @@ class ImageAdapter(
         val showAlreadyActionedImages =
             sharedPreferences.getBoolean(SHOW_ALREADY_ACTIONED_IMAGES_PREFERENCE_KEY, true)
 
-        // While switch is on initializes the holder with all images size
         return if (showAlreadyActionedImages) {
             allImages.size
-
-            // While switch is off and searching for next actionable has ended, initializes the holder
-            // with size of all actionable images
         } else if (actionableImagesMap.size == allImages.size || reachedEndOfFolder) {
             actionableImagesMap.size
-
-            // While switch is off, initializes the holder with and extra view holder so that finding
-            // and addition of the next actionable image in the adapter can be continued
         } else {
             actionableImagesMap.size + 1
         }