From 1856196851bf6db076ce1d637b1f516fa79e487a Mon Sep 17 00:00:00 2001
From: neslihanturan <tur.neslihan@gmail.com>
Date: Mon, 17 Aug 2020 14:30:46 +0300
Subject: [PATCH] Todo for user (#3851)

* Add a simple message

* Categories are edited

* Display categories

* read whole page

* Revert wrong changes

* Add newly added category field

* Doesnt displaey alreasy added categories

* add strings for notifications

* clean code

* Readd accidentally removed imports

* Fix edit layout style

* Fix category update messages

* Pass isWikipediaButtonDisplayed information to fragment

* Remove unused class

* Fix strings

* Fix string

* Add exeption for uncategorised images too

* Revert project.xml changes

* fix update buttonvisibility issue

* Make sure it works for auto added categories too

* make the button visible

* Make the button appear when categories are entered

* Include cancel button

* Make view updated too

* Make category view edited

* Update categories in an hacky way

* Fix unnecessary method call

* Add notes for short term fix to display added category

* Fix tests

* Fix strings

* Fix click issue
---
 .idea/codeStyles/Project.xml                  |   2 +-
 .../main/java/fr/free/nrw/commons/Media.kt    |  10 +
 .../nrw/commons/actions/PageEditClient.java   |  18 +-
 .../nrw/commons/category/CategoryClient.kt    |   2 +
 .../commons/category/CategoryEditHelper.java  | 109 ++++++++
 ...CategoryEditSearchRecyclerViewAdapter.java | 176 +++++++++++++
 .../contributions/ContributionViewHolder.java |   4 +-
 .../contributions/ContributionsFragment.java  |   4 +-
 .../ContributionsListAdapter.java             |   3 +-
 .../ContributionsListFragment.java            |  11 +-
 .../commons/media/MediaDetailFragment.java    | 232 +++++++++++++++++-
 .../media/MediaDetailPagerFragment.java       |   9 +-
 .../notification/NotificationHelper.java      |   1 +
 .../nrw/commons/widget/PicOfDayAppWidget.java |   5 +-
 .../main/res/drawable/ic_baseline_edit_24.xml |  10 +
 .../main/res/layout/fragment_media_detail.xml |  57 ++++-
 .../res/layout/layout_edit_categories.xml     | 114 +++++++++
 .../res/layout/layout_edit_category_item.xml  |  27 ++
 app/src/main/res/values/strings.xml           |  15 ++
 .../nrw/commons/actions/PageEditClientTest.kt |  26 +-
 20 files changed, 799 insertions(+), 36 deletions(-)
 create mode 100644 app/src/main/java/fr/free/nrw/commons/category/CategoryEditHelper.java
 create mode 100644 app/src/main/java/fr/free/nrw/commons/category/CategoryEditSearchRecyclerViewAdapter.java
 create mode 100644 app/src/main/res/drawable/ic_baseline_edit_24.xml
 create mode 100644 app/src/main/res/layout/layout_edit_categories.xml
 create mode 100644 app/src/main/res/layout/layout_edit_category_item.xml

diff --git a/.idea/codeStyles/Project.xml b/.idea/codeStyles/Project.xml
index 405537524..084bac90e 100644
--- a/.idea/codeStyles/Project.xml
+++ b/.idea/codeStyles/Project.xml
@@ -325,4 +325,4 @@
       </indentOptions>
     </codeStyleSettings>
   </code_scheme>
-</component>
\ No newline at end of file
+</component>
diff --git a/app/src/main/java/fr/free/nrw/commons/Media.kt b/app/src/main/java/fr/free/nrw/commons/Media.kt
index 1aad1ea38..e2580284f 100644
--- a/app/src/main/java/fr/free/nrw/commons/Media.kt
+++ b/app/src/main/java/fr/free/nrw/commons/Media.kt
@@ -121,4 +121,14 @@ class Media constructor(
         get() = captions[Locale.getDefault().language]
             ?: captions.values.firstOrNull()
             ?: displayTitle
+
+    /**
+     * Gets the categories the file falls under.
+     * @return file categories as an ArrayList of Strings
+     */
+    var addedCategories: List<String>? = null
+        // TODO added categories should be removed. It is added for a short fix. On category update,
+        //  categories should be re-fetched instead
+        get() = field                     // getter
+        set(value) { field = value }      // setter
 }
diff --git a/app/src/main/java/fr/free/nrw/commons/actions/PageEditClient.java b/app/src/main/java/fr/free/nrw/commons/actions/PageEditClient.java
index 46005d006..a2d7bd543 100644
--- a/app/src/main/java/fr/free/nrw/commons/actions/PageEditClient.java
+++ b/app/src/main/java/fr/free/nrw/commons/actions/PageEditClient.java
@@ -1,5 +1,7 @@
 package fr.free.nrw.commons.actions;
 
+import io.reactivex.Single;
+import io.reactivex.SingleOnSubscribe;
 import org.wikipedia.csrf.CsrfTokenClient;
 import org.wikipedia.dataclient.Service;
 
@@ -48,12 +50,16 @@ public class PageEditClient {
      * @param summary     Edit summary
      */
     public Observable<Boolean> appendEdit(String pageTitle, String appendText, String summary) {
-        try {
-            return pageEditInterface.postAppendEdit(pageTitle, summary, appendText, csrfTokenClient.getTokenBlocking())
-                    .map(editResponse -> editResponse.edit().editSucceeded());
-        } catch (Throwable throwable) {
-            return Observable.just(false);
-        }
+        return Single.create((SingleOnSubscribe<String>) emitter -> {
+            try {
+                emitter.onSuccess(csrfTokenClient.getTokenBlocking());
+            } catch (Throwable throwable) {
+                emitter.onError(throwable);
+                throwable.printStackTrace();
+            }
+        }).flatMapObservable(token -> pageEditInterface.postAppendEdit(pageTitle, summary, appendText, token)
+            .map(editResponse -> editResponse.edit().editSucceeded()));
+
     }
 
     /**
diff --git a/app/src/main/java/fr/free/nrw/commons/category/CategoryClient.kt b/app/src/main/java/fr/free/nrw/commons/category/CategoryClient.kt
index 2af925317..bcdb1cdd7 100644
--- a/app/src/main/java/fr/free/nrw/commons/category/CategoryClient.kt
+++ b/app/src/main/java/fr/free/nrw/commons/category/CategoryClient.kt
@@ -8,6 +8,8 @@ import javax.inject.Singleton
 const val CATEGORY_PREFIX = "Category:"
 const val SUB_CATEGORY_CONTINUATION_PREFIX = "sub_category_"
 const val PARENT_CATEGORY_CONTINUATION_PREFIX = "parent_category_"
+const val CATEGORY_UNCATEGORISED = "uncategorised"
+const val CATEGORY_NEEDING_CATEGORIES = "needing categories"
 
 /**
  * Category Client to handle custom calls to Commons MediaWiki APIs
diff --git a/app/src/main/java/fr/free/nrw/commons/category/CategoryEditHelper.java b/app/src/main/java/fr/free/nrw/commons/category/CategoryEditHelper.java
new file mode 100644
index 000000000..7fa637b97
--- /dev/null
+++ b/app/src/main/java/fr/free/nrw/commons/category/CategoryEditHelper.java
@@ -0,0 +1,109 @@
+package fr.free.nrw.commons.category;
+
+import static fr.free.nrw.commons.notification.NotificationHelper.NOTIFICATION_EDIT_CATEGORY;
+
+import android.content.Context;
+import android.content.Intent;
+import android.net.Uri;
+import android.util.Log;
+import fr.free.nrw.commons.BuildConfig;
+import fr.free.nrw.commons.Media;
+import fr.free.nrw.commons.R;
+import fr.free.nrw.commons.actions.PageEditClient;
+import fr.free.nrw.commons.notification.NotificationHelper;
+import fr.free.nrw.commons.utils.ViewUtilWrapper;
+import io.reactivex.Observable;
+import io.reactivex.Single;
+import java.util.List;
+import javax.inject.Inject;
+import javax.inject.Named;
+import timber.log.Timber;
+
+public class CategoryEditHelper {
+    private final NotificationHelper notificationHelper;
+    public final PageEditClient pageEditClient;
+    private final ViewUtilWrapper viewUtil;
+    private final String username;
+    private Callback callback;
+
+    @Inject
+    public CategoryEditHelper(NotificationHelper notificationHelper,
+        @Named("commons-page-edit") PageEditClient pageEditClient,
+        ViewUtilWrapper viewUtil,
+        @Named("username") String username) {
+        this.notificationHelper = notificationHelper;
+        this.pageEditClient = pageEditClient;
+        this.viewUtil = viewUtil;
+        this.username = username;
+    }
+
+    /**
+     * Public interface to edit categories
+     * @param context
+     * @param media
+     * @param categories
+     * @return
+     */
+    public Single<Boolean> makeCategoryEdit(Context context, Media media, List<String> categories, Callback callback) {
+        viewUtil.showShortToast(context, context.getString(R.string.category_edit_helper_make_edit_toast));
+        return addCategory(media, categories)
+            .flatMapSingle(result -> Single.just(showCategoryEditNotification(context, media, result)))
+            .firstOrError();
+    }
+
+    /**
+     * Appends new categories
+     * @param media
+     * @param categories to be added
+     * @return
+     */
+    private Observable<Boolean> addCategory(Media media, List<String> categories) {
+        Timber.d("thread is category adding %s", Thread.currentThread().getName());
+        String summary = "Adding categories";
+
+        StringBuilder buffer = new StringBuilder();
+
+        if (categories != null && categories.size() != 0) {
+
+            for (int i = 0; i < categories.size(); i++) {
+                buffer.append("\n[[Category:").append(categories.get(i)).append("]]");
+            }
+        } else {
+            buffer.append("{{subst:unc}}");
+        }
+        String appendText = buffer.toString();
+        return pageEditClient.appendEdit(media.getFilename(), appendText + "\n", summary);
+    }
+
+    private boolean showCategoryEditNotification(Context context, Media media, boolean result) {
+        String message;
+        String title = context.getString(R.string.category_edit_helper_show_edit_title);
+
+        if (result) {
+            title += ": " + context.getString(R.string.category_edit_helper_show_edit_title_success);
+            StringBuilder categoriesInMessage = new StringBuilder();
+            List<String> mediaCategoryList = media.getCategories();
+            for (String category : mediaCategoryList) {
+                categoriesInMessage.append(category);
+                if (category.equals(mediaCategoryList.get(mediaCategoryList.size()-1))) {
+                    continue;
+                }
+                categoriesInMessage.append(",");
+            }
+
+            message = context.getResources().getQuantityString(R.plurals.category_edit_helper_show_edit_message_if, mediaCategoryList.size(), categoriesInMessage.toString());
+        } else {
+            title += ": " + context.getString(R.string.category_edit_helper_show_edit_title);
+            message = context.getString(R.string.category_edit_helper_edit_message_else) ;
+        }
+
+        String urlForFile = BuildConfig.COMMONS_URL + "/wiki/" + media.getFilename();
+        Intent browserIntent = new Intent(Intent.ACTION_VIEW, Uri.parse(urlForFile));
+        notificationHelper.showNotification(context, title, message, NOTIFICATION_EDIT_CATEGORY, browserIntent);
+        return result;
+    }
+
+    public interface  Callback {
+        boolean updateCategoryDisplay(List<String> categories);
+    }
+}
diff --git a/app/src/main/java/fr/free/nrw/commons/category/CategoryEditSearchRecyclerViewAdapter.java b/app/src/main/java/fr/free/nrw/commons/category/CategoryEditSearchRecyclerViewAdapter.java
new file mode 100644
index 000000000..78342777d
--- /dev/null
+++ b/app/src/main/java/fr/free/nrw/commons/category/CategoryEditSearchRecyclerViewAdapter.java
@@ -0,0 +1,176 @@
+package fr.free.nrw.commons.category;
+
+import android.content.Context;
+import android.view.LayoutInflater;
+import android.view.View;
+import android.view.ViewGroup;
+import android.widget.CheckBox;
+import android.widget.CompoundButton;
+import android.widget.CompoundButton.OnCheckedChangeListener;
+import android.widget.Filter;
+import android.widget.Filterable;
+import android.widget.TextView;
+import androidx.annotation.NonNull;
+import androidx.recyclerview.widget.RecyclerView;
+import fr.free.nrw.commons.R;
+import fr.free.nrw.commons.category.CategoryEditSearchRecyclerViewAdapter.RecyclerViewHolder;
+import fr.free.nrw.commons.nearby.Label;
+import java.util.ArrayList;
+import java.util.List;
+
+public class CategoryEditSearchRecyclerViewAdapter
+    extends RecyclerView.Adapter<RecyclerViewHolder>
+    implements Filterable {
+
+    private List<String> displayedCategories;
+    private List<String> categories = new ArrayList<>();
+    private List<String> newCategories = new ArrayList<>();
+    private final LayoutInflater inflater;
+    private CategoryClient categoryClient;
+    private Context context;
+
+    private Callback callback;
+
+    public CategoryEditSearchRecyclerViewAdapter(Context context, ArrayList<Label> labels,
+        RecyclerView categoryRecyclerView, CategoryClient categoryClient, Callback callback) {
+        this.context = context;
+        inflater = LayoutInflater.from(context);
+        this.categoryClient = categoryClient;
+        this.callback = callback;
+    }
+
+    public void addToCategories(List<String> categories) {
+        for(String category : categories) {
+            if (!this.categories.contains(category)) {
+                this.categories.add(category);
+            }
+        }
+    }
+
+    public void addToCategories(String categoryToBeAdded) {
+        if (!categories.contains(categoryToBeAdded)) {
+            categories.add(categoryToBeAdded);
+        }
+    }
+
+    public void removeFromCategories(String categoryToBeRemoved) {
+        if (categories.contains(categoryToBeRemoved)) {
+            categories.remove(categoryToBeRemoved);
+        }
+    }
+
+    public void removeFromNewCategories(String categoryToBeRemoved) {
+        if (newCategories.contains(categoryToBeRemoved)) {
+            newCategories.remove(categoryToBeRemoved);
+        }
+    }
+
+    public void addToNewCategories(List<String> newCategories) {
+        for(String category : newCategories) {
+            if (!this.newCategories.contains(category)) {
+                this.newCategories.add(category);
+            }
+        }
+    }
+
+    public void addToNewCategories(String addedCategory) {
+        if (!newCategories.contains(addedCategory)) {
+            newCategories.add(addedCategory);
+        }
+    }
+
+    public List<String> getCategories() {
+        return categories;
+    }
+
+    public List<String> getNewCategories() {
+        return newCategories;
+    }
+
+    @Override
+    public Filter getFilter() {
+        return new Filter() {
+
+            @Override
+            protected FilterResults performFiltering(CharSequence constraint) {
+                FilterResults results = new FilterResults();
+                List<String> resultCategories = categoryClient.searchCategories(constraint.toString(), 10).blockingGet();
+                results.values = resultCategories;
+                results.count = resultCategories.size();
+                return results;
+            }
+
+            @Override
+            protected void publishResults(CharSequence constraint, FilterResults results) {
+                List<String> resultList = (List<String>)results.values;
+                // Do not re-add already added categories
+                for (String category : categories) {
+                    if (resultList.contains(category)) {
+                        resultList.remove(category);
+                    }
+                }
+
+                displayedCategories = resultList;
+                notifyDataSetChanged();
+                if (displayedCategories.size()==0) {
+                    callback.noResultsFound();
+                } else {
+                    callback.someResultsFound();
+                }
+            }
+        };
+    }
+
+    public class RecyclerViewHolder extends RecyclerView.ViewHolder {
+        public CheckBox categoryCheckBox;
+        public TextView categoryTextView;
+
+        public RecyclerViewHolder(View view) {
+            super(view);
+            categoryCheckBox = view.findViewById(R.id.category_checkbox);
+            categoryTextView = view.findViewById(R.id.category_text);
+            categoryCheckBox.setOnCheckedChangeListener(new OnCheckedChangeListener() {
+                @Override
+                public void onCheckedChanged(CompoundButton buttonView, boolean isChecked) {
+                    if (isChecked) {
+                        addToNewCategories(categoryTextView.getText().toString());
+                    } else {
+                        removeFromNewCategories(categoryTextView.getText().toString());
+                    }
+                    List<String> allCategories = new ArrayList<>();
+                    allCategories.addAll(categories);
+                    allCategories.addAll(newCategories);
+                    callback.updateSelectedCategoriesTextView(allCategories);
+                }
+            });
+        }
+    }
+
+    @NonNull
+    @Override
+    public RecyclerViewHolder onCreateViewHolder(@NonNull ViewGroup parent, int viewType) {
+        View itemView = inflater.inflate(R.layout.layout_edit_category_item , parent, false);
+        return new RecyclerViewHolder(itemView);
+    }
+
+    @Override
+    public void onBindViewHolder(@NonNull RecyclerViewHolder holder, int position) {
+        holder.categoryTextView.setText(displayedCategories.get(position));
+    }
+
+    @Override
+    public long getItemId(int position) {
+        return displayedCategories.get(position).hashCode();
+    }
+
+    @Override
+    public int getItemCount() {
+        return (displayedCategories == null) ? 0 : displayedCategories.size();
+    }
+
+    public interface  Callback {
+        void updateSelectedCategoriesTextView(List<String> selectedCategories);
+        void noResultsFound();
+        void someResultsFound();
+    }
+}
diff --git a/app/src/main/java/fr/free/nrw/commons/contributions/ContributionViewHolder.java b/app/src/main/java/fr/free/nrw/commons/contributions/ContributionViewHolder.java
index ae81f8b76..6e3e7b21c 100644
--- a/app/src/main/java/fr/free/nrw/commons/contributions/ContributionViewHolder.java
+++ b/app/src/main/java/fr/free/nrw/commons/contributions/ContributionViewHolder.java
@@ -51,6 +51,7 @@ public class ContributionViewHolder extends RecyclerView.ViewHolder {
   private Contribution contribution;
   private final CompositeDisposable compositeDisposable = new CompositeDisposable();
   private final MediaClient mediaClient;
+  private boolean isWikipediaButtonDisplayed;
 
   ContributionViewHolder(final View parent, final Callback callback,
       final MediaClient mediaClient) {
@@ -160,6 +161,7 @@ public class ContributionViewHolder extends RecyclerView.ViewHolder {
   private void displayWikipediaButton(Boolean mediaExists) {
     if (!mediaExists) {
       addToWikipediaButton.setVisibility(View.VISIBLE);
+      isWikipediaButtonDisplayed = true;
       cancelButton.setVisibility(View.GONE);
       retryButton.setVisibility(View.GONE);
       imageOptions.setVisibility(View.VISIBLE);
@@ -199,7 +201,7 @@ public class ContributionViewHolder extends RecyclerView.ViewHolder {
 
   @OnClick(R.id.contributionImage)
   public void imageClicked() {
-    callback.openMediaDetail(position);
+    callback.openMediaDetail(position, isWikipediaButtonDisplayed);
   }
 
   @OnClick(R.id.wikipediaButton)
diff --git a/app/src/main/java/fr/free/nrw/commons/contributions/ContributionsFragment.java b/app/src/main/java/fr/free/nrw/commons/contributions/ContributionsFragment.java
index 8a8df6025..13c9a10c2 100644
--- a/app/src/main/java/fr/free/nrw/commons/contributions/ContributionsFragment.java
+++ b/app/src/main/java/fr/free/nrw/commons/contributions/ContributionsFragment.java
@@ -482,12 +482,12 @@ public class ContributionsFragment
      * contribution.
      */
     @Override
-    public void showDetail(int position) {
+    public void showDetail(int position, boolean isWikipediaButtonDisplayed) {
         if (mediaDetailPagerFragment == null || !mediaDetailPagerFragment.isVisible()) {
             mediaDetailPagerFragment = new MediaDetailPagerFragment();
             showMediaDetailPagerFragment();
         }
-        mediaDetailPagerFragment.showImage(position);
+        mediaDetailPagerFragment.showImage(position, isWikipediaButtonDisplayed);
     }
 
     @Override
diff --git a/app/src/main/java/fr/free/nrw/commons/contributions/ContributionsListAdapter.java b/app/src/main/java/fr/free/nrw/commons/contributions/ContributionsListAdapter.java
index b08b355b1..e6db7e3de 100644
--- a/app/src/main/java/fr/free/nrw/commons/contributions/ContributionsListAdapter.java
+++ b/app/src/main/java/fr/free/nrw/commons/contributions/ContributionsListAdapter.java
@@ -7,7 +7,6 @@ import androidx.paging.PagedListAdapter;
 import androidx.recyclerview.widget.DiffUtil;
 import fr.free.nrw.commons.R;
 import fr.free.nrw.commons.media.MediaClient;
-import org.wikipedia.dataclient.WikiSite;
 
     /**
  * Represents The View Adapter for the List of Contributions
@@ -75,7 +74,7 @@ public class ContributionsListAdapter extends
 
         void deleteUpload(Contribution contribution);
 
-        void openMediaDetail(int contribution);
+        void openMediaDetail(int contribution, boolean isWikipediaPageExists);
 
         void addImageToWikipedia(Contribution contribution);
 
diff --git a/app/src/main/java/fr/free/nrw/commons/contributions/ContributionsListFragment.java b/app/src/main/java/fr/free/nrw/commons/contributions/ContributionsListFragment.java
index 5d14cb01e..998b5d510 100644
--- a/app/src/main/java/fr/free/nrw/commons/contributions/ContributionsListFragment.java
+++ b/app/src/main/java/fr/free/nrw/commons/contributions/ContributionsListFragment.java
@@ -29,9 +29,8 @@ import fr.free.nrw.commons.Media;
 import fr.free.nrw.commons.R;
 import fr.free.nrw.commons.Utils;
 import fr.free.nrw.commons.di.CommonsDaggerSupportFragment;
-import fr.free.nrw.commons.media.MediaClient;
 import fr.free.nrw.commons.utils.DialogUtil;
-import fr.free.nrw.commons.wikidata.WikidataEditService;
+import fr.free.nrw.commons.media.MediaClient;
 import java.util.Locale;
 import javax.inject.Inject;
 import javax.inject.Named;
@@ -244,9 +243,9 @@ public class ContributionsListFragment extends CommonsDaggerSupportFragment impl
   }
 
   @Override
-  public void openMediaDetail(final int position) {
+  public void openMediaDetail(final int position, boolean isWikipediaButtonDisplayed) {
     if (null != callback) {//Just being safe, ideally they won't be called when detached
-      callback.showDetail(position);
+      callback.showDetail(position, isWikipediaButtonDisplayed);
     }
   }
 
@@ -334,8 +333,8 @@ public class ContributionsListFragment extends CommonsDaggerSupportFragment impl
 
     void retryUpload(Contribution contribution);
 
-    void pauseUpload(Contribution contribution);
+    void showDetail(int position, boolean isWikipediaButtonDisplayed);
 
-    void showDetail(int position);
+    void pauseUpload(Contribution contribution);
   }
 }
diff --git a/app/src/main/java/fr/free/nrw/commons/media/MediaDetailFragment.java b/app/src/main/java/fr/free/nrw/commons/media/MediaDetailFragment.java
index 2f0968ef4..eb5148fe7 100644
--- a/app/src/main/java/fr/free/nrw/commons/media/MediaDetailFragment.java
+++ b/app/src/main/java/fr/free/nrw/commons/media/MediaDetailFragment.java
@@ -2,7 +2,9 @@ package fr.free.nrw.commons.media;
 
 import static android.view.View.GONE;
 import static android.view.View.VISIBLE;
+import static fr.free.nrw.commons.category.CategoryClientKt.CATEGORY_NEEDING_CATEGORIES;
 import static fr.free.nrw.commons.category.CategoryClientKt.CATEGORY_PREFIX;
+import static fr.free.nrw.commons.category.CategoryClientKt.CATEGORY_UNCATEGORISED;
 
 import android.annotation.SuppressLint;
 import android.app.AlertDialog;
@@ -13,7 +15,9 @@ import android.graphics.drawable.Animatable;
 import android.net.Uri;
 import android.os.Bundle;
 import android.text.Editable;
+import android.text.TextUtils;
 import android.text.TextWatcher;
+import android.util.Log;
 import android.view.LayoutInflater;
 import android.view.View;
 import android.view.ViewGroup;
@@ -23,11 +27,15 @@ import android.widget.ArrayAdapter;
 import android.widget.Button;
 import android.widget.EditText;
 import android.widget.LinearLayout;
+import android.widget.ProgressBar;
 import android.widget.ScrollView;
+import android.widget.SearchView;
 import android.widget.Spinner;
 import android.widget.TextView;
 import android.widget.Toast;
 import androidx.annotation.Nullable;
+import androidx.recyclerview.widget.LinearLayoutManager;
+import androidx.recyclerview.widget.RecyclerView;
 import butterknife.BindView;
 import butterknife.ButterKnife;
 import butterknife.OnClick;
@@ -38,6 +46,8 @@ import com.facebook.drawee.interfaces.DraweeController;
 import com.facebook.drawee.view.SimpleDraweeView;
 import com.facebook.imagepipeline.image.ImageInfo;
 import com.facebook.imagepipeline.request.ImageRequest;
+import com.jakewharton.rxbinding2.view.RxView;
+import com.jakewharton.rxbinding2.widget.RxSearchView;
 import fr.free.nrw.commons.Media;
 import fr.free.nrw.commons.MediaDataExtractor;
 import fr.free.nrw.commons.R;
@@ -45,13 +55,18 @@ import fr.free.nrw.commons.Utils;
 import fr.free.nrw.commons.auth.AccountUtil;
 import fr.free.nrw.commons.category.CategoryClient;
 import fr.free.nrw.commons.category.CategoryDetailsActivity;
+import fr.free.nrw.commons.category.CategoryEditHelper;
+import fr.free.nrw.commons.category.CategoryEditSearchRecyclerViewAdapter;
+import fr.free.nrw.commons.category.CategoryEditSearchRecyclerViewAdapter.Callback;
 import fr.free.nrw.commons.contributions.ContributionsFragment;
 import fr.free.nrw.commons.delete.DeleteHelper;
 import fr.free.nrw.commons.delete.ReasonBuilder;
 import fr.free.nrw.commons.explore.depictions.WikidataItemDetailsActivity;
 import fr.free.nrw.commons.di.CommonsDaggerSupportFragment;
+import fr.free.nrw.commons.nearby.Label;
 import fr.free.nrw.commons.ui.widget.HtmlTextView;
 import fr.free.nrw.commons.utils.ViewUtilWrapper;
+import io.reactivex.Observable;
 import io.reactivex.Single;
 import io.reactivex.android.schedulers.AndroidSchedulers;
 import io.reactivex.schedulers.Schedulers;
@@ -59,22 +74,25 @@ import java.util.ArrayList;
 import java.util.Date;
 import java.util.List;
 import java.util.Locale;
+import java.util.concurrent.TimeUnit;
 import java.util.Map;
 import javax.inject.Inject;
 import org.apache.commons.lang3.StringUtils;
 import org.wikipedia.util.DateUtil;
 import timber.log.Timber;
 
-public class MediaDetailFragment extends CommonsDaggerSupportFragment {
+public class MediaDetailFragment extends CommonsDaggerSupportFragment implements Callback,
+    CategoryEditHelper.Callback {
 
     private boolean editable;
     private boolean isCategoryImage;
     private MediaDetailPagerFragment.MediaDetailProvider detailProvider;
     private int index;
     private boolean isDeleted = false;
+    private boolean isWikipediaButtonDisplayed;
 
 
-    public static MediaDetailFragment forMedia(int index, boolean editable, boolean isCategoryImage) {
+    public static MediaDetailFragment forMedia(int index, boolean editable, boolean isCategoryImage, boolean isWikipediaButtonDisplayed) {
         MediaDetailFragment mf = new MediaDetailFragment();
 
         Bundle state = new Bundle();
@@ -83,6 +101,7 @@ public class MediaDetailFragment extends CommonsDaggerSupportFragment {
         state.putInt("index", index);
         state.putInt("listIndex", 0);
         state.putInt("listTop", 0);
+        state.putBoolean("isWikipediaButtonDisplayed", isWikipediaButtonDisplayed);
 
         mf.setArguments(state);
 
@@ -96,7 +115,11 @@ public class MediaDetailFragment extends CommonsDaggerSupportFragment {
     @Inject
     DeleteHelper deleteHelper;
     @Inject
+    CategoryEditHelper categoryEditHelper;
+    @Inject
     ViewUtilWrapper viewUtil;
+    @Inject
+    CategoryClient categoryClient;
 
     private int initialListTop = 0;
 
@@ -132,6 +155,8 @@ public class MediaDetailFragment extends CommonsDaggerSupportFragment {
     LinearLayout nominatedForDeletion;
     @BindView(R.id.mediaDetailCategoryContainer)
     LinearLayout categoryContainer;
+    @BindView(R.id.categoryEditButton)
+    Button categoryEditButton;
     @BindView(R.id.media_detail_depiction_container)
     LinearLayout depictionContainer;
     @BindView(R.id.authorLinearLayout)
@@ -140,6 +165,29 @@ public class MediaDetailFragment extends CommonsDaggerSupportFragment {
     Button delete;
     @BindView(R.id.mediaDetailScrollView)
     ScrollView scrollView;
+    @BindView(R.id.toDoLayout)
+    LinearLayout toDoLayout;
+    @BindView(R.id.toDoReason)
+    TextView toDoReason;
+    @BindView(R.id.category_edit_layout)
+    LinearLayout categoryEditLayout;
+    @BindView(R.id.et_search)
+    SearchView categorySearchView;
+    @BindView(R.id.rv_categories)
+    RecyclerView categoryRecyclerView;
+    @BindView(R.id.update_categories_button)
+    Button updateCategoriesButton;
+    @BindView(R.id.dummy_category_edit_container)
+    LinearLayout dummyCategoryEditContainer;
+    @BindView(R.id.pb_categories)
+    ProgressBar progressbarCategories;
+    @BindView(R.id.existing_categories)
+    TextView existingCategories;
+    @BindView(R.id.no_results_found)
+    TextView noResultsFound;
+
+    private ArrayList<String> categoryNames = new ArrayList<>();
+    private String categorySearchQuery;
 
     /**
      * Depicts is a feature part of Structured data. Multiple Depictions can be added for an image just like categories.
@@ -151,6 +199,7 @@ public class MediaDetailFragment extends CommonsDaggerSupportFragment {
     private int newWidthOfImageView;
     private boolean heightVerifyingBoolean = true; // helps in maintaining aspect ratio
     private ViewTreeObserver.OnGlobalLayoutListener layoutListener; // for layout stuff, only used once!
+    private CategoryEditSearchRecyclerViewAdapter categoryEditSearchRecyclerViewAdapter;
 
     //Had to make this class variable, to implement various onClicks, which access the media, also I fell why make separate variables when one can serve the purpose
     private Media media;
@@ -163,6 +212,7 @@ public class MediaDetailFragment extends CommonsDaggerSupportFragment {
         outState.putInt("index", index);
         outState.putBoolean("editable", editable);
         outState.putBoolean("isCategoryImage", isCategoryImage);
+        outState.putBoolean("isWikipediaButtonDisplayed", isWikipediaButtonDisplayed);
 
         getScrollPosition();
         outState.putInt("listTop", initialListTop);
@@ -182,11 +232,13 @@ public class MediaDetailFragment extends CommonsDaggerSupportFragment {
         if (savedInstanceState != null) {
             editable = savedInstanceState.getBoolean("editable");
             isCategoryImage = savedInstanceState.getBoolean("isCategoryImage");
+            isWikipediaButtonDisplayed = savedInstanceState.getBoolean("isWikipediaButtonDisplayed");
             index = savedInstanceState.getInt("index");
             initialListTop = savedInstanceState.getInt("listTop");
         } else {
             editable = getArguments().getBoolean("editable");
             isCategoryImage = getArguments().getBoolean("isCategoryImage");
+            isWikipediaButtonDisplayed = getArguments().getBoolean("isWikipediaButtonDisplayed");
             index = getArguments().getInt("index");
             initialListTop = 0;
         }
@@ -232,6 +284,12 @@ public class MediaDetailFragment extends CommonsDaggerSupportFragment {
                     .getParentFragment())).nearbyNotificationCardView
                     .setVisibility(View.GONE);
         }
+        categoryEditSearchRecyclerViewAdapter =
+            new CategoryEditSearchRecyclerViewAdapter(getContext(), new ArrayList<>(
+                Label.valuesAsList()), categoryRecyclerView, categoryClient, this);
+        categoryRecyclerView.setLayoutManager(new LinearLayoutManager(getActivity()));
+        categoryRecyclerView.setAdapter(categoryEditSearchRecyclerViewAdapter);
+
         media = detailProvider.getMediaAtPosition(index);
         scrollView.getViewTreeObserver().addOnGlobalLayoutListener(
             new OnGlobalLayoutListener() {
@@ -311,6 +369,8 @@ public class MediaDetailFragment extends CommonsDaggerSupportFragment {
                 .observeOn(AndroidSchedulers.mainThread())
                 .subscribe(this::onDepictionsLoaded, Timber::e)
         );
+        // compositeDisposable.add(disposable);
+        setupToDo();
     }
 
     private void onDiscussionLoaded(String discussion) {
@@ -385,6 +445,63 @@ public class MediaDetailFragment extends CommonsDaggerSupportFragment {
         imageLandscape.setController(controllerLandscape);
     }
 
+    /**
+     * Displays layout about missing actions to inform user
+     * - Images that they uploaded with no categories/descriptions, so that they can add them
+     * - Images that can be added to associated Wikipedia articles that have no pictures
+     */
+    private void setupToDo() {
+        updateToDoWarning();
+        compositeDisposable.add(RxSearchView.queryTextChanges(categorySearchView)
+            .takeUntil(RxView.detaches(categorySearchView))
+            .debounce(500, TimeUnit.MILLISECONDS)
+            .observeOn(AndroidSchedulers.mainThread())
+            .subscribe(query -> {
+                    this.categorySearchQuery = query.toString();
+                    //update image list
+                    if (!TextUtils.isEmpty(query)) {
+                        if (categoryEditLayout.getVisibility() == VISIBLE) {
+                            ((CategoryEditSearchRecyclerViewAdapter) categoryRecyclerView.getAdapter()).
+                                getFilter().filter(query.toString());
+                        }
+                    }
+                }, Timber::e
+            ));
+    }
+
+    private void updateToDoWarning() {
+        String toDoMessage = "";
+        boolean toDoNeeded = false;
+        boolean categoriesPresent = media.getCategories() == null ? false : (media.getCategories().size() == 0 ? false : true);
+
+        // Check if the presented category is about need of category
+        if (categoriesPresent) {
+            for (String category : media.getCategories()) {
+                if (category.toLowerCase().contains(CATEGORY_NEEDING_CATEGORIES) ||
+                    category.toLowerCase().contains(CATEGORY_UNCATEGORISED)) {
+                    categoriesPresent = false;
+                }
+                break;
+            }
+        }
+        if (!categoriesPresent) {
+            toDoNeeded = true;
+            toDoMessage += getString(R.string.missing_category);
+        }
+        if (isWikipediaButtonDisplayed) {
+            toDoNeeded = true;
+            toDoMessage += (toDoMessage.isEmpty()) ? "" : "\n" + getString(R.string.missing_article);
+        }
+
+        if (toDoNeeded) {
+            toDoMessage = getString(R.string.todo_improve) + "\n" + toDoMessage;
+            toDoLayout.setVisibility(VISIBLE);
+            toDoReason.setText(toDoMessage);
+        } else {
+            toDoLayout.setVisibility(GONE);
+        }
+    }
+
     @Override
     public void onDestroyView() {
         if (layoutListener != null && getView() != null) {
@@ -409,15 +526,12 @@ public class MediaDetailFragment extends CommonsDaggerSupportFragment {
             mediaCaption.setText(prettyCaption(media));
         }
 
-        final List<String> categories = media.getCategories();
-        if (categories.isEmpty()) {
-            // Stick in a filler element.
-            categories.add(getString(R.string.detail_panel_cats_none));
-        }
-
-        rebuildCatList(categories);
-
+        categoryNames.clear();
+        categoryNames.addAll(media.getCategories());
+        categoryEditSearchRecyclerViewAdapter.addToCategories(media.getCategories());
+        updateSelectedCategoriesTextView(categoryEditSearchRecyclerViewAdapter.getCategories());
 
+        updateCategoryList();
 
         if (media.getCreator() == null || media.getCreator().equals("")) {
             authorLayout.setVisibility(GONE);
@@ -426,6 +540,49 @@ public class MediaDetailFragment extends CommonsDaggerSupportFragment {
         }
     }
 
+    private void updateCategoryList() {
+        List<String> allCategories = new ArrayList<String>( media.getCategories());
+        if (media.getAddedCategories() != null) {
+            // TODO this added categories logic should be removed.
+            //  It is just a short term hack. Categories should be fetch everytime they are updated.
+            // if media.getCategories contains addedCategory, then do not re-add them
+            for (String addedCategory : media.getAddedCategories()) {
+                if (allCategories.contains(addedCategory)) {
+                    media.setAddedCategories(null);
+                    break;
+                }
+            }
+            allCategories.addAll(media.getAddedCategories());
+        }
+        if (allCategories.isEmpty()) {
+            // Stick in a filler element.
+            allCategories.add(getString(R.string.detail_panel_cats_none));
+        }
+
+        rebuildCatList(allCategories);
+    }
+
+    @Override
+    public void updateSelectedCategoriesTextView(List<String> selectedCategories) {
+        if (selectedCategories == null || selectedCategories.size() == 0) {
+            updateCategoriesButton.setClickable(false);
+        }
+        if (selectedCategories != null) {
+            existingCategories.setText(StringUtils.join(selectedCategories,", "));
+            updateCategoriesButton.setClickable(true);
+        }
+    }
+
+    @Override
+    public void noResultsFound() {
+        noResultsFound.setVisibility(VISIBLE);
+    }
+
+    @Override
+    public void someResultsFound() {
+        noResultsFound.setVisibility(GONE);
+    }
+
     /**
      * Populates media details fragment with depiction list
      * @param idAndCaptions
@@ -467,6 +624,50 @@ public class MediaDetailFragment extends CommonsDaggerSupportFragment {
         Toast.makeText(getContext(), getString(R.string.wikicode_copied), Toast.LENGTH_SHORT).show();
     }
 
+    @OnClick(R.id.dummy_category_edit_container)
+    public void onOutsideOfCategoryEditClicked() {
+        if (dummyCategoryEditContainer.getVisibility() == VISIBLE) {
+            dummyCategoryEditContainer.setVisibility(GONE);
+        }
+    }
+
+    @OnClick(R.id.categoryEditButton)
+    public void onCategoryEditButtonClicked(){
+        displayHideCategorySearch();
+    }
+
+    public void displayHideCategorySearch() {
+        if (dummyCategoryEditContainer.getVisibility() != VISIBLE) {
+            dummyCategoryEditContainer.setVisibility(VISIBLE);
+        } else {
+            dummyCategoryEditContainer.setVisibility(GONE);
+        }
+    }
+
+    @OnClick(R.id.update_categories_button)
+    public void onUpdateCategoriesClicked() {
+        updateCategories(categoryEditSearchRecyclerViewAdapter.getNewCategories());
+        displayHideCategorySearch();
+    }
+
+    @OnClick(R.id.cancel_categories_button)
+    public void onCancelCategoriesClicked() {
+        displayHideCategorySearch();
+    }
+
+    public void updateCategories(List<String> selectedCategories) {
+        compositeDisposable.add(categoryEditHelper.makeCategoryEdit(getContext(), media, selectedCategories, this)
+            .subscribeOn(Schedulers.io())
+            .observeOn(AndroidSchedulers.mainThread())
+            .subscribe(s -> {
+                Timber.d("Categories are added.");
+                onOutsideOfCategoryEditClicked();
+                media.setAddedCategories(selectedCategories);
+                updateCategoryList();
+            }));
+    }
+
+    @SuppressLint("StringFormatInvalid")
     @OnClick(R.id.nominateDeletion)
     public void onDeleteButtonClicked(){
             if (AccountUtil.getUserName(getContext()) != null && AccountUtil.getUserName(getContext()).equals(media.getCreator())) {
@@ -537,7 +738,6 @@ public class MediaDetailFragment extends CommonsDaggerSupportFragment {
             }
         }
 
-
     @SuppressLint("CheckResult")
     private void onDeleteClicked(Spinner spinner) {
         String reason = spinner.getSelectedItem().toString();
@@ -588,6 +788,7 @@ public class MediaDetailFragment extends CommonsDaggerSupportFragment {
     }
 
     private void rebuildCatList(List<String> categories) {
+        Log.d("deneme","rebuild cat list size:"+categories.size());
         categoryContainer.removeAllViews();
         for (String category : categories) {
             categoryContainer.addView(buildCatLabel(sanitise(category), categoryContainer));
@@ -706,4 +907,13 @@ public class MediaDetailFragment extends CommonsDaggerSupportFragment {
         return media.getCoordinates().getPrettyCoordinateString();
     }
 
+    @Override
+    public boolean updateCategoryDisplay(List<String> categories) {
+        if (categories == null) {
+            return false;
+        } else {
+            rebuildCatList(categories);
+            return true;
+        }
+    }
 }
diff --git a/app/src/main/java/fr/free/nrw/commons/media/MediaDetailPagerFragment.java b/app/src/main/java/fr/free/nrw/commons/media/MediaDetailPagerFragment.java
index f98e66db3..5e1b7e8ef 100644
--- a/app/src/main/java/fr/free/nrw/commons/media/MediaDetailPagerFragment.java
+++ b/app/src/main/java/fr/free/nrw/commons/media/MediaDetailPagerFragment.java
@@ -41,6 +41,7 @@ public class MediaDetailPagerFragment extends CommonsDaggerSupportFragment imple
     @BindView(R.id.mediaDetailsPager) ViewPager pager;
     private Boolean editable;
     private boolean isFeaturedImage;
+    private boolean isWikipediaButtonDisplayed;
     MediaDetailAdapter adapter;
     private Bookmark bookmark;
     private MediaDetailProvider provider;
@@ -249,6 +250,12 @@ public class MediaDetailPagerFragment extends CommonsDaggerSupportFragment imple
         item.setIcon(icon);
     }
 
+    public void showImage(int i, boolean isWikipediaButtonDisplayed) {
+        this.isWikipediaButtonDisplayed = isWikipediaButtonDisplayed;
+        Handler handler =  new Handler();
+        handler.postDelayed(() -> pager.setCurrentItem(i), 5);
+    }
+
     public void showImage(int i) {
         Handler handler =  new Handler();
         handler.postDelayed(() -> pager.setCurrentItem(i), 5);
@@ -310,7 +317,7 @@ public class MediaDetailPagerFragment extends CommonsDaggerSupportFragment imple
                 }
                 pager.postDelayed(() -> getActivity().invalidateOptionsMenu(), 5);
             }
-            return MediaDetailFragment.forMedia(i, editable, isFeaturedImage);
+            return MediaDetailFragment.forMedia(i, editable, isFeaturedImage, isWikipediaButtonDisplayed);
         }
 
         @Override
diff --git a/app/src/main/java/fr/free/nrw/commons/notification/NotificationHelper.java b/app/src/main/java/fr/free/nrw/commons/notification/NotificationHelper.java
index d950502c9..76b51bb57 100644
--- a/app/src/main/java/fr/free/nrw/commons/notification/NotificationHelper.java
+++ b/app/src/main/java/fr/free/nrw/commons/notification/NotificationHelper.java
@@ -24,6 +24,7 @@ import static androidx.core.app.NotificationCompat.PRIORITY_HIGH;
 public class NotificationHelper {
 
     public static final int NOTIFICATION_DELETE = 1;
+    public static final int NOTIFICATION_EDIT_CATEGORY = 2;
 
     private NotificationManager notificationManager;
     private NotificationCompat.Builder notificationBuilder;
diff --git a/app/src/main/java/fr/free/nrw/commons/widget/PicOfDayAppWidget.java b/app/src/main/java/fr/free/nrw/commons/widget/PicOfDayAppWidget.java
index 41bc04fdf..e3d989798 100644
--- a/app/src/main/java/fr/free/nrw/commons/widget/PicOfDayAppWidget.java
+++ b/app/src/main/java/fr/free/nrw/commons/widget/PicOfDayAppWidget.java
@@ -23,12 +23,12 @@ import com.facebook.imagepipeline.image.CloseableImage;
 import com.facebook.imagepipeline.request.ImageRequest;
 import com.facebook.imagepipeline.request.ImageRequestBuilder;
 
+import fr.free.nrw.commons.media.MediaClient;
 import javax.inject.Inject;
 
 import fr.free.nrw.commons.R;
 import fr.free.nrw.commons.contributions.MainActivity;
 import fr.free.nrw.commons.di.ApplicationlessInjection;
-import fr.free.nrw.commons.media.MediaClient;
 import io.reactivex.android.schedulers.AndroidSchedulers;
 import io.reactivex.disposables.CompositeDisposable;
 import io.reactivex.schedulers.Schedulers;
@@ -43,7 +43,8 @@ public class PicOfDayAppWidget extends AppWidgetProvider {
 
     private CompositeDisposable compositeDisposable = new CompositeDisposable();
 
-    @Inject MediaClient mediaClient;
+    @Inject
+    MediaClient mediaClient;
 
     void updateAppWidget(Context context, AppWidgetManager appWidgetManager, int appWidgetId) {
         RemoteViews views = new RemoteViews(context.getPackageName(), R.layout.pic_of_day_app_widget);
diff --git a/app/src/main/res/drawable/ic_baseline_edit_24.xml b/app/src/main/res/drawable/ic_baseline_edit_24.xml
new file mode 100644
index 000000000..2844bafeb
--- /dev/null
+++ b/app/src/main/res/drawable/ic_baseline_edit_24.xml
@@ -0,0 +1,10 @@
+<vector xmlns:android="http://schemas.android.com/apk/res/android"
+    android:width="24dp"
+    android:height="24dp"
+    android:viewportWidth="24"
+    android:viewportHeight="24"
+    android:tint="?attr/colorControlNormal">
+  <path
+      android:fillColor="@android:color/white"
+      android:pathData="M3,17.25V21h3.75L17.81,9.94l-3.75,-3.75L3,17.25zM20.71,7.04c0.39,-0.39 0.39,-1.02 0,-1.41l-2.34,-2.34c-0.39,-0.39 -1.02,-0.39 -1.41,0l-1.83,1.83 3.75,3.75 1.83,-1.83z"/>
+</vector>
diff --git a/app/src/main/res/layout/fragment_media_detail.xml b/app/src/main/res/layout/fragment_media_detail.xml
index 40264af8d..863f2cb4f 100644
--- a/app/src/main/res/layout/fragment_media_detail.xml
+++ b/app/src/main/res/layout/fragment_media_detail.xml
@@ -8,6 +8,20 @@
     android:background="?attr/mainBackground"
     >
 
+    <LinearLayout
+      android:id="@+id/dummy_category_edit_container"
+      android:layout_width="match_parent"
+      android:layout_height="match_parent"
+      android:elevation="35dp"
+      android:layout_gravity="bottom"
+      android:visibility="gone"
+      android:orientation="vertical"
+      android:weightSum="10">
+
+        <include
+          layout="@layout/layout_edit_categories" />
+    </LinearLayout>
+
     <ImageView
         android:id="@+id/mediaDetailImageFailed"
         android:layout_height="wrap_content"
@@ -53,9 +67,12 @@
 
                 <LinearLayout
                     android:layout_width="match_parent"
-                    android:layout_height="@dimen/dimen_250"
+                    android:layout_height="wrap_content"
                     android:orientation="vertical"
-                    android:id="@+id/mediaDetailImageViewSpacer" />
+                    android:id="@+id/mediaDetailImageViewSpacer"
+                  >
+
+                </LinearLayout>
 
             </FrameLayout>
 
@@ -88,6 +105,30 @@
                         tools:text="Title of the media" />
                 </LinearLayout>
 
+                <LinearLayout
+                  android:id="@+id/toDoLayout"
+                  android:layout_width="match_parent"
+                  android:layout_height="wrap_content"
+                  android:orientation="vertical"
+                  android:visibility="gone"
+                  android:background="@color/layout_light_grey"
+                  >
+
+                    <TextView
+                      android:layout_width="match_parent"
+                      android:layout_height="wrap_content"
+                      style="@style/MediaDetailTextLabel"
+                      android:text="@string/warning" />
+
+                    <TextView
+                      android:id="@+id/toDoReason"
+                      android:layout_width="match_parent"
+                      android:layout_height="wrap_content"
+                      android:layout_marginStart="@dimen/activity_margin_vertical"
+                      style="@style/MediaDetailTextBody" />
+
+                </LinearLayout>
+
                 <LinearLayout
                     style="@style/MediaDetailContainer"
                     android:layout_width="match_parent"
@@ -255,9 +296,19 @@
                         android:layout_width="@dimen/widget_margin"
                         android:layout_height="match_parent"
                         android:layout_weight="70"
-                        android:orientation="vertical" />
+                        android:orientation="vertical">
+                    </LinearLayout>
+
                 </LinearLayout>
 
+                <Button
+                  android:id="@+id/categoryEditButton"
+                  android:layout_width="24dp"
+                  android:layout_height="24dp"
+                  android:layout_margin="@dimen/standard_gap"
+                  android:layout_gravity="end"
+                  android:background="@drawable/ic_baseline_edit_24" />
+
                 <LinearLayout
                     style="@style/MediaDetailContainer"
                     android:layout_width="match_parent"
diff --git a/app/src/main/res/layout/layout_edit_categories.xml b/app/src/main/res/layout/layout_edit_categories.xml
new file mode 100644
index 000000000..aca58d040
--- /dev/null
+++ b/app/src/main/res/layout/layout_edit_categories.xml
@@ -0,0 +1,114 @@
+<?xml version="1.0" encoding="utf-8"?>
+<LinearLayout
+xmlns:android="http://schemas.android.com/apk/res/android" android:layout_width="match_parent"
+  android:id="@+id/category_edit_layout"
+  android:layout_height="wrap_content"
+  android:layout_margin="15dp"
+  android:orientation="vertical"
+  android:background="@color/white"
+  android:elevation="30dp">
+
+  <TextView
+    android:id="@+id/tv_subtitle"
+    android:layout_width="wrap_content"
+    android:layout_height="@dimen/half_standard_height"
+    android:layout_margin="@dimen/quarter_standard_height"
+    android:gravity="center_vertical"
+    android:text="Type categories"
+    android:textSize="@dimen/subtitle_text"
+    android:visibility="visible" />
+
+  <FrameLayout
+    android:id="@+id/category_search_layout"
+    android:layout_width="match_parent"
+    android:layout_height="wrap_content"
+    android:layout_marginTop="@dimen/standard_gap"
+    >
+    <com.google.android.material.textfield.TextInputLayout
+      android:id="@+id/til_container_search"
+      android:layout_width="match_parent"
+      android:layout_height="wrap_content">
+
+      <SearchView
+        android:id="@+id/et_search"
+        android:layout_width="match_parent"
+        android:layout_height="wrap_content"
+        android:hint="@string/categories_search_text_hint"
+        android:imeOptions="actionSearch"
+        android:inputType="text"
+        android:maxLines="1"/>
+    </com.google.android.material.textfield.TextInputLayout>
+
+    <ProgressBar
+      android:id="@+id/pb_categories"
+      style="?android:progressBarStyleSmall"
+      android:layout_width="wrap_content"
+      android:layout_height="wrap_content"
+      android:layout_marginEnd="@dimen/tiny_gap"
+      android:layout_marginRight="@dimen/tiny_gap"
+      android:layout_gravity="center_vertical|end"
+      android:indeterminate="true"
+      android:indeterminateOnly="true"
+      android:visibility="gone" />
+  </FrameLayout>
+
+  <TextView
+    android:id="@+id/existing_categories"
+    android:layout_width="match_parent"
+    android:layout_height="wrap_content"
+    android:layout_margin="@dimen/quarter_standard_height"
+    android:gravity="center_vertical"
+    android:textSize="@dimen/subtitle_text"
+    android:visibility="visible" />
+
+  <TextView
+    android:id="@+id/no_results_found"
+    android:layout_width="match_parent"
+    android:layout_height="wrap_content"
+    android:layout_margin="@dimen/quarter_standard_height"
+    android:gravity="center_vertical"
+    android:text="No results found"
+    android:textSize="@dimen/description_text_size"
+    android:visibility="gone" />
+  <LinearLayout
+    android:layout_width="match_parent"
+    android:layout_height="match_parent"
+    android:orientation="vertical"
+    android:weightSum="6"
+    >
+
+    <androidx.recyclerview.widget.RecyclerView
+      android:id="@+id/rv_categories"
+      android:layout_width="match_parent"
+      android:layout_height="0dp"
+      android:layout_weight="4"
+      android:background="@color/white"/>
+
+    <LinearLayout
+      android:layout_width="match_parent"
+      android:layout_height="0dp"
+      android:layout_weight="2">
+      <Button
+        android:id="@+id/cancel_categories_button"
+        android:layout_width="wrap_content"
+        android:layout_margin="@dimen/quarter_standard_height"
+        android:layout_height="wrap_content"
+        android:text="@string/cancel"
+        android:padding="@dimen/small_gap"
+        android:textColor="@color/white"
+        android:background="@color/opak_middle_grey"
+        />
+      <Button
+        android:id="@+id/update_categories_button"
+        android:layout_width="wrap_content"
+        android:layout_margin="@dimen/quarter_standard_height"
+        android:layout_height="wrap_content"
+        android:text="@string/category_edit_button_text"
+        android:padding="@dimen/small_gap"
+        android:textColor="@color/white"
+        android:background="@color/button_blue"
+        />
+    </LinearLayout>
+  </LinearLayout>
+
+</LinearLayout>
\ No newline at end of file
diff --git a/app/src/main/res/layout/layout_edit_category_item.xml b/app/src/main/res/layout/layout_edit_category_item.xml
new file mode 100644
index 000000000..b4d82dc20
--- /dev/null
+++ b/app/src/main/res/layout/layout_edit_category_item.xml
@@ -0,0 +1,27 @@
+<?xml version="1.0" encoding="utf-8"?>
+<androidx.constraintlayout.widget.ConstraintLayout xmlns:android="http://schemas.android.com/apk/res/android"
+  xmlns:app="http://schemas.android.com/apk/res-auto"
+  android:id="@+id/category_layout"
+  android:layout_width="match_parent"
+  android:layout_height="wrap_content"
+  android:orientation="horizontal">
+
+  <CheckBox
+    android:id="@+id/category_checkbox"
+    android:layout_width="wrap_content"
+    android:layout_height="wrap_content"
+    android:checkMark="?android:attr/textCheckMark"
+    android:checked="false"
+    android:gravity="center_vertical"
+    android:padding="@dimen/tiny_gap"
+    app:layout_constraintLeft_toLeftOf="parent"
+    app:layout_constraintTop_toTopOf="parent" />
+
+  <TextView
+    android:id="@+id/category_text"
+    android:layout_width="wrap_content"
+    android:layout_height="wrap_content"
+    android:text="Category"
+    app:layout_constraintLeft_toRightOf="@+id/category_checkbox"
+    app:layout_constraintTop_toTopOf="parent"/>
+</androidx.constraintlayout.widget.ConstraintLayout>
diff --git a/app/src/main/res/values/strings.xml b/app/src/main/res/values/strings.xml
index d666785dd..bf908f718 100644
--- a/app/src/main/res/values/strings.xml
+++ b/app/src/main/res/values/strings.xml
@@ -598,6 +598,17 @@ Upload your first media by tapping on the add button.</string>
   <string name="delete_helper_ask_reason_copyright_logo">Logo</string>
   <string name="delete_helper_ask_reason_copyright_other">Other</string>
   <string name="delete_helper_ask_alert_set_positive_button_reason">Because it is</string>
+
+  <string name="category_edit_helper_make_edit_toast">Trying to update categories.</string>
+  <string name="category_edit_helper_show_edit_title">Category update</string>
+  <string name="category_edit_helper_show_edit_title_success">Success</string>
+  <plurals name="category_edit_helper_show_edit_message_if">
+    <item quantity="one">Category %1$s is added.</item>
+    <item quantity="other">Categories %1$s are added.</item>
+  </plurals>
+  <string name="category_edit_helper_edit_message_else">Could not add categories.</string>
+  <string name="category_edit_button_text">Update categories</string>
+
   <string name="share_image_via">Share image via</string>
   <string name="no_achievements_yet">You haven\'t made any contributions yet</string>
   <string name="account_created">Account created!</string>
@@ -636,6 +647,10 @@ Upload your first media by tapping on the add button.</string>
   <string name="load_more">Load More</string>
   <string name="nearby_no_results">No places found, try changing your search criteria.</string>
 
+  <string name="todo_improve">Suggested improvements:</string>
+  <string name="missing_category">- Add categories to this image to improve usability.</string>
+  <string name="missing_article">- Add this image to the associated Wikipedia article that has no images.</string>
+  <string name="edit_category">Edit categories</string>
   <string name="add_picture_to_wikipedia_article_title">Add image to Wikipedia</string>
   <string name="add_picture_to_wikipedia_article_desc">Do you want to add this picture to the %1$s language Wikipedia article?</string>
 
diff --git a/app/src/test/kotlin/fr/free/nrw/commons/actions/PageEditClientTest.kt b/app/src/test/kotlin/fr/free/nrw/commons/actions/PageEditClientTest.kt
index dc635f43e..186b57610 100644
--- a/app/src/test/kotlin/fr/free/nrw/commons/actions/PageEditClientTest.kt
+++ b/app/src/test/kotlin/fr/free/nrw/commons/actions/PageEditClientTest.kt
@@ -2,13 +2,16 @@ package fr.free.nrw.commons.actions
 
 import com.nhaarman.mockitokotlin2.eq
 import com.nhaarman.mockitokotlin2.verify
+import io.reactivex.Observable
 import org.junit.Before
 import org.junit.Test
+import org.mockito.ArgumentMatchers
 import org.mockito.Mock
 import org.mockito.Mockito
 import org.mockito.MockitoAnnotations
 import org.wikipedia.csrf.CsrfTokenClient
 import org.wikipedia.dataclient.Service
+import org.wikipedia.edit.Edit
 
 class PageEditClientTest {
     @Mock
@@ -20,6 +23,12 @@ class PageEditClientTest {
 
     private lateinit var pageEditClient: PageEditClient
 
+    @Mock
+    lateinit var edit: Edit
+
+    @Mock
+    lateinit var editResult: Edit.Result
+
     /**
      * initial setup, test environment
      */
@@ -46,8 +55,23 @@ class PageEditClientTest {
     @Test
     fun testAppendEdit() {
         Mockito.`when`(csrfTokenClient.tokenBlocking).thenReturn("test")
-        pageEditClient.appendEdit("test", "test", "test")
+        Mockito.`when`(
+            pageEditInterface.postAppendEdit(
+                ArgumentMatchers.anyString(),
+                ArgumentMatchers.anyString(),
+                ArgumentMatchers.anyString(),
+                ArgumentMatchers.anyString()
+            )
+        ).thenReturn(
+            Observable.just(edit)
+        )
+        Mockito.`when`(edit.edit()).thenReturn(editResult)
+        Mockito.`when`(editResult.editSucceeded()).thenReturn(true)
+        pageEditClient.appendEdit("test", "test", "test").test()
+        verify(csrfTokenClient).tokenBlocking
         verify(pageEditInterface).postAppendEdit(eq("test"), eq("test"), eq("test"), eq("test"))
+        verify(edit).edit()
+        verify(editResult).editSucceeded()
     }
 
     /**