From 28ab24a4ecdc4bc33200b6ee6b051050b6b06686 Mon Sep 17 00:00:00 2001
From: Pi Patel <pi.patel@gmail.com>
Date: Tue, 28 Apr 2026 04:59:28 +0530
Subject: [PATCH] area: upload: Fix duplicate validation bypass and thread
 starvation

* Replaced synchronous .blockingGet() with .await() in CustomSelectorUtils.kt to prevent IO dispatcher starvation.

* Overloaded checkImageQuality in UploadMediaDetailsContract and Presenter to allow single-parameter (index) validation without breaking existing call sites.

* Triggered image verification in UploadMediaDetailFragment's onBecameVisible to ensure validation fires on ViewPager swipe.

Fixes #6401
---
 .../upload/mediaDetails/UploadMediaDetailFragment.kt |  3 +++
 .../mediaDetails/UploadMediaDetailsContract.kt       |  6 ++++++
 .../upload/mediaDetails/UploadMediaPresenter.kt      | 12 ++++++++++++
 .../fr/free/nrw/commons/utils/CustomSelectorUtils.kt |  4 +++-
 4 files changed, 24 insertions(+), 1 deletion(-)

diff --git a/app/src/main/java/fr/free/nrw/commons/upload/mediaDetails/UploadMediaDetailFragment.kt b/app/src/main/java/fr/free/nrw/commons/upload/mediaDetails/UploadMediaDetailFragment.kt
index 8c2faff3433..20e996a4f05 100644
--- a/app/src/main/java/fr/free/nrw/commons/upload/mediaDetails/UploadMediaDetailFragment.kt
+++ b/app/src/main/java/fr/free/nrw/commons/upload/mediaDetails/UploadMediaDetailFragment.kt
@@ -495,6 +495,9 @@ class UploadMediaDetailFragment : UploadBaseFragment(), UploadMediaDetailsContra
             return
         }
         presenter.fetchTitleAndDescription(indexOfFragment)
+        if (indexOfFragment > 0) {
+            presenter.checkImageQuality(indexOfFragment)
+        }
         if (showNearbyFound) {
             if (UploadActivity.nearbyPopupAnswers!!.containsKey(nearbyPlace!!)) {
                 val response = UploadActivity.nearbyPopupAnswers!![nearbyPlace!!]!!
diff --git a/app/src/main/java/fr/free/nrw/commons/upload/mediaDetails/UploadMediaDetailsContract.kt b/app/src/main/java/fr/free/nrw/commons/upload/mediaDetails/UploadMediaDetailsContract.kt
index d6d77420852..a5501eb1128 100644
--- a/app/src/main/java/fr/free/nrw/commons/upload/mediaDetails/UploadMediaDetailsContract.kt
+++ b/app/src/main/java/fr/free/nrw/commons/upload/mediaDetails/UploadMediaDetailsContract.kt
@@ -105,6 +105,12 @@ interface UploadMediaDetailsContract {
          */
         fun checkImageQuality(uploadItem: UploadItem, index: Int)
 
+        /**
+         * Forces a check on the image quality for a specific fragment index
+         * * @param index Index of the UploadItem whose quality is to be checked
+         */
+        fun checkImageQuality(index: Int)
+
         /**
          * Updates the image qualities stored in JSON, whenever an image is deleted
          *
diff --git a/app/src/main/java/fr/free/nrw/commons/upload/mediaDetails/UploadMediaPresenter.kt b/app/src/main/java/fr/free/nrw/commons/upload/mediaDetails/UploadMediaPresenter.kt
index 6e26e02a6cc..243b1c0e544 100644
--- a/app/src/main/java/fr/free/nrw/commons/upload/mediaDetails/UploadMediaPresenter.kt
+++ b/app/src/main/java/fr/free/nrw/commons/upload/mediaDetails/UploadMediaPresenter.kt
@@ -372,6 +372,18 @@ class UploadMediaPresenter @Inject constructor(
         }
     }
 
+    /**
+     * Forces a check on the image quality for a specific fragment index
+     *
+     * @param index Index of the UploadItem whose quality is to be checked
+     */
+    override fun checkImageQuality(index: Int) {
+        val uploadItems = repository.getUploads()
+        if (index in uploadItems.indices) {
+            checkImageQuality(uploadItems[index], index)
+        }
+    }
+
     /**
      * Updates the image qualities stored in JSON, whenever an image is deleted
      *
diff --git a/app/src/main/java/fr/free/nrw/commons/utils/CustomSelectorUtils.kt b/app/src/main/java/fr/free/nrw/commons/utils/CustomSelectorUtils.kt
index 79cf87e538a..02aee73d12d 100644
--- a/app/src/main/java/fr/free/nrw/commons/utils/CustomSelectorUtils.kt
+++ b/app/src/main/java/fr/free/nrw/commons/utils/CustomSelectorUtils.kt
@@ -12,6 +12,7 @@ import fr.free.nrw.commons.upload.FileProcessor
 import fr.free.nrw.commons.upload.FileUtilsWrapper
 import kotlinx.coroutines.CoroutineDispatcher
 import kotlinx.coroutines.withContext
+import kotlinx.coroutines.rx2.await
 import timber.log.Timber
 import java.io.FileNotFoundException
 import java.io.IOException
@@ -82,7 +83,8 @@ class CustomSelectorUtils {
             withContext(ioDispatcher) {
                 var result: ImageLoader.Result = ImageLoader.Result.FALSE
                 try {
-                    if (mediaClient.checkFileExistsUsingSha(SHA1).blockingGet()) {
+                    // Changed .blockingGet() to .await()
+                    if (mediaClient.checkFileExistsUsingSha(SHA1).await()) {
                         result = ImageLoader.Result.TRUE
                     }
                 } catch (e: Exception) {