experimental headlines loader with diffutil

5 files changed, 454 insertions, 21 deletions

diff --git a/org.fox.ttrss/src/main/java/org/fox/ttrss/Application.java b/org.fox.ttrss/src/main/java/org/fox/ttrss/Application.java
index 07f1a3b5..9ad069f1 100755
--- a/org.fox.ttrss/src/main/java/org/fox/ttrss/Application.java
+++ b/org.fox.ttrss/src/main/java/org/fox/ttrss/Application.java
@@ -1,5 +1,8 @@
 package org.fox.ttrss;
 
+import android.content.Context;
+import android.net.ConnectivityManager;
+import android.net.NetworkInfo;
 import android.os.Bundle;
 
 import org.fox.ttrss.types.ArticleList;
@@ -17,6 +20,7 @@ public class Application extends android.app.Application {
 	private String m_sessionId;
 	private int m_apiLevel;
 	public LinkedHashMap<String, String> m_customSortModes = new LinkedHashMap<>();
+	ConnectivityManager m_cmgr;
 
 	public static Application getInstance(){
 		return m_singleton;
@@ -31,6 +35,7 @@ public class Application extends android.app.Application {
 		super.onCreate();
 
 		m_singleton = this;
+		m_cmgr = (ConnectivityManager) getSystemService(Context.CONNECTIVITY_SERVICE);
 	}
 
 	public String getSessionId() {
@@ -68,6 +73,15 @@ public class Application extends android.app.Application {
 			m_customSortModes.clear();
 			m_customSortModes.putAll(tmp);
 		}
-				
 	}
+
+	public boolean isWifiConnected() {
+		NetworkInfo wifi = m_cmgr.getNetworkInfo(ConnectivityManager.TYPE_WIFI);
+
+		if (wifi != null)
+			return wifi.isConnected();
+
+		return false;
+	}
+
 }
diff --git a/org.fox.ttrss/src/main/java/org/fox/ttrss/ArticlePager.java b/org.fox.ttrss/src/main/java/org/fox/ttrss/ArticlePager.java
index da9dc8f3..46cf36ee 100755
--- a/org.fox.ttrss/src/main/java/org/fox/ttrss/ArticlePager.java
+++ b/org.fox.ttrss/src/main/java/org/fox/ttrss/ArticlePager.java
@@ -146,8 +146,12 @@ public class ArticlePager extends androidx.fragment.app.Fragment {
 
 		return view;
 	}
-	
+
 	protected void refresh(final boolean append) {
+		//
+	}
+
+	/* protected void refresh(final boolean append) {
 
 		if (!append) {
 			m_lazyLoadDisabled = false;
@@ -291,7 +295,7 @@ public class ArticlePager extends androidx.fragment.app.Fragment {
 		Log.d(TAG, "[AP] request more headlines, firstId=" + m_firstId);
 
 		req.execute(map);
-	}
+	} */
 	
 	@Override
 	public void onAttach(@NonNull Activity activity) {
diff --git a/org.fox.ttrss/src/main/java/org/fox/ttrss/HeadlinesFragment.java b/org.fox.ttrss/src/main/java/org/fox/ttrss/HeadlinesFragment.java
index ad023a7e..0030d2a6 100755
--- a/org.fox.ttrss/src/main/java/org/fox/ttrss/HeadlinesFragment.java
+++ b/org.fox.ttrss/src/main/java/org/fox/ttrss/HeadlinesFragment.java
@@ -44,11 +44,16 @@ import android.widget.PopupMenu;
 import android.widget.ProgressBar;
 import android.widget.TextView;
 
+import androidx.annotation.NonNull;
+import androidx.annotation.Nullable;
 import androidx.core.app.ActivityCompat;
 import androidx.core.app.ActivityOptionsCompat;
 import androidx.core.view.ViewCompat;
+import androidx.loader.app.LoaderManager;
+import androidx.loader.content.Loader;
 import androidx.preference.PreferenceManager;
 import androidx.recyclerview.widget.DefaultItemAnimator;
+import androidx.recyclerview.widget.DiffUtil;
 import androidx.recyclerview.widget.ItemTouchHelper;
 import androidx.recyclerview.widget.LinearLayoutManager;
 import androidx.recyclerview.widget.RecyclerView;
@@ -84,7 +89,106 @@ import java.util.TimeZone;
 
 import jp.wasabeef.glide.transformations.CropCircleTransformation;
 
-public class HeadlinesFragment extends androidx.fragment.app.Fragment {
+public class HeadlinesFragment extends androidx.fragment.app.Fragment implements LoaderManager.LoaderCallbacks<ArticleList> {
+
+	public class HeadlinesDiffutilCallback extends DiffUtil.Callback {
+		private ArticleList m_oldList;
+		private ArticleList m_newList;
+
+		public HeadlinesDiffutilCallback(ArticleList oldList, ArticleList newList) {
+			m_oldList = oldList;
+			m_newList = newList;
+		}
+
+		@Override
+		public int getOldListSize() {
+			return m_oldList != null ? m_oldList.size() : 0;
+		}
+
+		@Override
+		public int getNewListSize() {
+			return m_newList != null ? m_newList.size() : 0;
+		}
+
+		@Override
+		public boolean areItemsTheSame(int oldItemPosition, int newItemPosition) {
+			return m_newList.get(newItemPosition).id == m_oldList.get(oldItemPosition).id;
+		}
+
+		@Override
+		public boolean areContentsTheSame(int oldItemPosition, int newItemPosition) {
+			return false;
+		}
+	}
+
+
+	private HeadlinesLoader m_loader;
+
+	@NonNull
+	@Override
+	public Loader<ArticleList> onCreateLoader(int id, @Nullable Bundle args) {
+		return new HeadlinesLoader(getContext(), m_feed, m_activity.getResizeWidth());
+	}
+
+	@Override
+	public void onLoadFinished(@NonNull Loader<ArticleList> loader, ArticleList data) {
+		Log.d(TAG, "onLoadFinished loader=" + loader + " count=" + data.size());
+
+		HeadlinesLoader headlinesLoader = (HeadlinesLoader) loader;
+
+		// successful update
+		if (data != null) {
+			ArticleList articles = Application.getArticles();
+
+			articles.stripFooters();
+
+			DiffUtil.DiffResult diffResult = DiffUtil.calculateDiff(new HeadlinesDiffutilCallback(articles, data));
+
+			articles.clear();
+			articles.addAll(data);
+
+			diffResult.dispatchUpdatesTo(m_adapter);
+
+			// detail activity does not use footers (see above)
+			if (!(m_activity instanceof DetailActivity)) {
+				articles.add(new Article(Article.TYPE_AMR_FOOTER));
+				m_adapter.notifyItemInserted(articles.size());
+			}
+
+			if (!headlinesLoader.getAppend())
+				m_list.scrollToPosition(0);
+
+			//m_adapter.notifyDataSetChanged();
+
+			if (headlinesLoader.getFirstIdChanged()) {
+				//if (m_activity.isSmallScreen() || !m_activity.isPortrait()) {
+					Snackbar.make(getView(), R.string.headlines_row_top_changed, Snackbar.LENGTH_LONG)
+							.setAction(R.string.reload, v -> refresh(false)).show();
+				//}
+			}
+
+		} else {
+			if (headlinesLoader.getLastError() == ApiCommon.ApiError.LOGIN_FAILED) {
+				m_activity.login();
+			} else {
+
+				if (headlinesLoader.getLastErrorMessage() != null) {
+					m_activity.toast(m_activity.getString(headlinesLoader.getErrorMessage()) + "\n" + headlinesLoader.getLastErrorMessage());
+				} else {
+					m_activity.toast(headlinesLoader.getErrorMessage());
+				}
+			}
+
+		}
+
+		if (m_swipeLayout != null)
+			m_swipeLayout.setRefreshing(false);
+	}
+
+	@Override
+	public void onLoaderReset(@NonNull Loader<ArticleList> loader) {
+
+	}
 
 	public enum ArticlesSelection { ALL, NONE, UNREAD }
 
@@ -98,7 +202,7 @@ public class HeadlinesFragment extends androidx.fragment.app.Fragment {
 	private String m_searchQuery = "";
 	private boolean m_refreshInProgress = false;
 	private int m_firstId = 0;
-	private boolean m_lazyLoadDisabled = false;
+	//private boolean m_lazyLoadDisabled = false;
 
 	private SharedPreferences m_prefs;
 
@@ -251,7 +355,6 @@ public class HeadlinesFragment extends androidx.fragment.app.Fragment {
 			m_activeArticleId = savedInstanceState.getInt("m_activeArticleId");
 			m_searchQuery = savedInstanceState.getString("m_searchQuery");
 			m_firstId = savedInstanceState.getInt("m_firstId");
-			m_lazyLoadDisabled = savedInstanceState.getBoolean("m_lazyLoadDisabled");
 			m_compactLayoutMode = savedInstanceState.getBoolean("m_compactLayoutMode");
 		}
 
@@ -268,7 +371,6 @@ public class HeadlinesFragment extends androidx.fragment.app.Fragment {
 		out.putInt("m_activeArticleId", m_activeArticleId);
 		out.putString("m_searchQuery", m_searchQuery);
 		out.putInt("m_firstId", m_firstId);
-		out.putBoolean("m_lazyLoadDisabled", m_lazyLoadDisabled);
 		out.putBoolean("m_compactLayoutMode", m_compactLayoutMode);
 	}
 
@@ -287,7 +389,7 @@ public class HeadlinesFragment extends androidx.fragment.app.Fragment {
 
 		m_swipeLayout = view.findViewById(R.id.headlines_swipe_container);
 
-	    m_swipeLayout.setOnRefreshListener(() -> refresh(false, true));
+	    m_swipeLayout.setOnRefreshListener(() -> refresh(false));
 
 		m_list = view.findViewById(R.id.headlines_list);
 		registerForContextMenu(m_list);
@@ -394,6 +496,11 @@ public class HeadlinesFragment extends androidx.fragment.app.Fragment {
 
 						new Handler().postDelayed(() -> m_activity.refresh(false), 100);
 					}
+
+					int lastVisibleItem = m_layoutManager.findLastVisibleItemPosition();
+
+					if (lastVisibleItem >= Application.getArticles().size() - 5)
+						new Handler().postDelayed(() -> refresh(true), 100);
 				}
 			}
 
@@ -423,11 +530,13 @@ public class HeadlinesFragment extends androidx.fragment.app.Fragment {
 					}
 				}
 
-				if (!m_refreshInProgress && !m_lazyLoadDisabled && lastVisibleItem >= Application.getArticles().size() - 5) {
+				/*if (!m_refreshInProgress && !m_lazyLoadDisabled && lastVisibleItem >= Application.getArticles().size() - 5) {
 					m_refreshInProgress = true;
 					new Handler().postDelayed(() -> refresh(true), 100);
-				}
+				}*/
 
+				/* if (lastVisibleItem >= Application.getArticles().size() - 5)
+					new Handler().postDelayed(() -> refresh(true), 100); */
 			}
 		});
 
@@ -444,7 +553,9 @@ public class HeadlinesFragment extends androidx.fragment.app.Fragment {
 	public void onResume() {
 		super.onResume();
 
-        if (Application.getArticles().isEmpty()) {
+		m_loader = (HeadlinesLoader) LoaderManager.getInstance(this).initLoader(0, null, this);
+
+        if (Application.getArticles().getSizeWithoutFooters() == 0) {
             refresh(false);
         } else {
 			Article activeArticle = Application.getArticles().getById(m_activeArticleId);
@@ -464,11 +575,20 @@ public class HeadlinesFragment extends androidx.fragment.app.Fragment {
 		m_listener = (HeadlinesEventListener) activity;
 	}
 
-	public void refresh(boolean append) {
-		refresh(append, false);
+	public void refresh(final boolean append) {
+
+		if (!(m_activity instanceof DetailActivity)) {
+			// detail activity does not use footers because it would break 1-to-1 mapping with pager view
+			// pager will need to work on a footerless subset of shared article view before this is possible
+
+			Application.getArticles().add(new Article(Article.TYPE_LOADMORE));
+			m_adapter.notifyDataSetChanged();
+		}
+
+		m_loader.refresh(append);
 	}
 
-	public void refresh(final boolean append, boolean userInitiated) {
+	/* public void __refresh(final boolean append) {
 		Application.getArticles().stripFooters();
 		m_adapter.notifyDataSetChanged();
 
@@ -557,10 +677,9 @@ public class HeadlinesFragment extends androidx.fragment.app.Fragment {
 			final int skip = getSkip(append);
 
 			final boolean allowForceUpdate = m_activity.getApiLevel() >= 9 &&
-					!m_feed.is_cat && m_feed.id > 0 && !append && userInitiated &&
-					skip == 0;
+					!m_feed.is_cat && m_feed.id > 0 && !append && skip == 0;
 
-			Log.d(TAG, "allowForceUpdate=" + allowForceUpdate + " userInitiated=" + userInitiated + " skip=" + skip);
+			Log.d(TAG, "allowForceUpdate=" + allowForceUpdate + " skip=" + skip);
 
 			req.setOffset(skip);
 
@@ -636,7 +755,7 @@ public class HeadlinesFragment extends androidx.fragment.app.Fragment {
 		}
 
 		return skip;
-	}
+	} */
 
 	static class ArticleViewHolder extends RecyclerView.ViewHolder {
 		public View view;
@@ -1531,11 +1650,13 @@ public class HeadlinesFragment extends androidx.fragment.app.Fragment {
 	}
 
 	public void setSelection(ArticlesSelection select) {
-		for (Article a : Application.getArticles())
+		ArticleList articlesWithoutFooters = Application.getArticles().getWithoutFooters();
+
+		for (Article a : articlesWithoutFooters)
             a.selected = false;
 
 		if (select != ArticlesSelection.NONE) {
-			for (Article a : Application.getArticles()) {
+			for (Article a : articlesWithoutFooters) {
 				if (select == ArticlesSelection.ALL || select == ArticlesSelection.UNREAD && a.unread) {
 					a.selected = true;
 				}
diff --git a/org.fox.ttrss/src/main/java/org/fox/ttrss/HeadlinesLoader.java b/org.fox.ttrss/src/main/java/org/fox/ttrss/HeadlinesLoader.java
new file mode 100755
index 00000000..5cd7503c
--- /dev/null
+++ b/org.fox.ttrss/src/main/java/org/fox/ttrss/HeadlinesLoader.java
@@ -0,0 +1,292 @@
+package org.fox.ttrss;
+
+import android.content.Context;
+import android.content.SharedPreferences;
+import android.util.Log;
+
+import androidx.loader.content.AsyncTaskLoader;
+import androidx.preference.PreferenceManager;
+
+import com.google.gson.Gson;
+import com.google.gson.JsonArray;
+import com.google.gson.JsonElement;
+import com.google.gson.JsonObject;
+import com.google.gson.reflect.TypeToken;
+
+import org.fox.ttrss.ApiCommon.ApiError;
+import org.fox.ttrss.types.Article;
+import org.fox.ttrss.types.ArticleList;
+import org.fox.ttrss.types.Feed;
+
+import java.lang.reflect.Type;
+import java.util.HashMap;
+import java.util.List;
+
+public class HeadlinesLoader extends AsyncTaskLoader<ArticleList> implements ApiCommon.ApiCaller {
+	private final String TAG = this.getClass().getSimpleName();
+
+	private final int m_responseCode = 0;
+	protected String m_responseMessage;
+	private int m_apiStatusCode = 0;
+
+	private Context m_context;
+	private String m_lastErrorMessage;
+	private ApiError m_lastError;
+	private ArticleList m_articles;
+	private Feed m_feed;
+	private SharedPreferences m_prefs;
+	private int m_firstId;
+	private String m_searchQuery = "";
+	private boolean m_firstIdChanged;
+	private int m_offset;
+	private int m_amountLoaded;
+	private int m_resizeWidth;
+	private boolean m_append;
+	private boolean m_lazyLoadEnabled;
+	private boolean m_loadingInProgress;
+
+	HeadlinesLoader(Context context, Feed feed, int resizeWidth) {
+		super(context);
+
+		m_context = context;
+		m_lastError = ApiError.NO_ERROR;
+		m_feed = feed;
+		m_articles = new ArticleList();
+		m_resizeWidth = resizeWidth;
+		m_prefs = PreferenceManager.getDefaultSharedPreferences(context);
+	}
+
+	protected void refresh(boolean append) {
+		Log.d(TAG, "refresh, append=" + append + " inProgress=" + m_loadingInProgress + " lazyLoadEnabled=" + m_lazyLoadEnabled);
+
+		if (!append) {
+			m_append = false;
+			m_lazyLoadEnabled = true;
+
+			forceLoad();
+		} else if (!m_loadingInProgress && m_lazyLoadEnabled) {
+			m_append = true;
+			forceLoad();
+		} else {
+			deliverResult(m_articles);
+		}
+	}
+
+	@Override
+	protected void onStartLoading() {
+		if (m_articles != null) {
+			deliverResult(m_articles);
+		} else {
+			forceLoad();
+		}
+	}
+
+	@Override
+	public void deliverResult(ArticleList data) {
+		m_articles = data;
+
+		super.deliverResult(m_articles);
+	}
+
+	public int getErrorMessage() {
+		return ApiCommon.getErrorMessage(m_lastError);
+	}
+
+	ApiError getLastError() {
+		return m_lastError;
+	}
+
+	String getLastErrorMessage() {
+		return m_lastErrorMessage;
+	}
+
+	public boolean lazyLoadEnabled() {
+		return m_lazyLoadEnabled;
+	}
+
+	@Override
+	public ArticleList loadInBackground() {
+
+		m_loadingInProgress = true;
+
+		final int skip = getSkip(m_append);
+		final boolean allowForceUpdate = Application.getInstance().getApiLevel() >= 9 &&
+				!m_feed.is_cat && m_feed.id > 0 && !m_append && skip == 0;
+
+		HashMap<String,String> params = new HashMap<>();
+
+		params.put("op", "getHeadlines");
+		params.put("sid", Application.getInstance().getSessionId());
+		params.put("feed_id", String.valueOf(m_feed.id));
+		params.put("show_excerpt", "true");
+		params.put("excerpt_length", String.valueOf(CommonActivity.EXCERPT_MAX_LENGTH));
+		params.put("show_content", "true");
+		params.put("include_attachments", "true");
+		params.put("view_mode", m_prefs.getString("view_mode", "adaptive"));
+		params.put("limit", m_prefs.getString("headlines_request_size", "15"));
+		params.put("skip", String.valueOf(skip));
+		params.put("include_nested", "true");
+		params.put("has_sandbox", "true");
+		params.put("order_by", m_prefs.getString("headlines_sort_mode", "default"));
+
+		if (m_prefs.getBoolean("enable_image_downsampling", false)) {
+			if (m_prefs.getBoolean("always_downsample_images", false) || !Application.getInstance().isWifiConnected()) {
+				params.put("resize_width", String.valueOf(m_resizeWidth));
+			}
+		}
+
+		if (m_feed.is_cat)
+			params.put("is_cat", "true");
+
+		if (allowForceUpdate) {
+			params.put("force_update", "true");
+		}
+
+		if (m_searchQuery != null && !m_searchQuery.isEmpty()) {
+			params.put("search", m_searchQuery);
+			params.put("search_mode", "");
+			params.put("match_on", "both");
+		}
+
+		if (m_firstId > 0)
+			params.put("check_first_id", String.valueOf(m_firstId));
+
+		if (Application.getInstance().getApiLevel() >= 12) {
+			params.put("include_header", "true");
+		}
+
+		Log.d(TAG, "request more headlines, firstId=" + m_firstId + ", append=" + m_append + ", skip=" + skip);
+
+		JsonElement result = ApiCommon.performRequest(m_context, params, this);
+
+		Log.d(TAG, "got result=" + result);
+
+		if (result != null) {
+			try {
+				JsonArray content = result.getAsJsonArray();
+				if (content != null) {
+					final List<Article> articlesJson;
+					final JsonObject header;
+
+					if (Application.getInstance().getApiLevel() >= 12) {
+						header = content.get(0).getAsJsonObject();
+
+						m_firstIdChanged = header.get("first_id_changed") != null;
+
+						try {
+							m_firstId = header.get("first_id").getAsInt();
+						} catch (NumberFormatException e) {
+							m_firstId = 0;
+						}
+
+						Log.d(TAG, "firstID=" + m_firstId + " firstIdChanged=" + m_firstIdChanged);
+
+						Type listType = new TypeToken<List<Article>>() {}.getType();
+						articlesJson = new Gson().fromJson(content.get(1), listType);
+					} else {
+						Type listType = new TypeToken<List<Article>>() {}.getType();
+						articlesJson = new Gson().fromJson(content, listType);
+					}
+
+					if (skip == 0)
+						m_articles.clear();
+					/* else
+						m_articles.stripFooters(); */
+
+					m_amountLoaded = articlesJson.size();
+
+					for (Article f : articlesJson)
+						if (!m_articles.containsId(f.id)) {
+							f.collectMediaInfo();
+							f.cleanupExcerpt();
+							m_articles.add(f);
+						}
+
+					if (m_firstIdChanged) {
+						Log.d(TAG, "first id changed, disabling lazy load");
+						m_lazyLoadEnabled = false;
+					}
+
+					if (m_amountLoaded < Integer.parseInt(m_prefs.getString("headlines_request_size", "15"))) {
+						Log.d(TAG, "amount loaded "+m_amountLoaded+" < request size, disabling lazy load");
+						m_lazyLoadEnabled = false;
+					}
+
+					m_loadingInProgress = false;
+
+					return m_articles;
+				}
+
+			} catch (Exception e) {
+				e.printStackTrace();
+			}
+		}
+
+		m_loadingInProgress = false;
+
+		return null;
+
+		/* TODO move to onLoaderFinished() if (m_lastError == ApiCommon.ApiError.LOGIN_FAILED) {
+			m_activity.login();
+		} else {
+
+			if (m_lastErrorMessage != null) {
+				m_activity.toast(m_activity.getString(getErrorMessage()) + "\n" + m_lastErrorMessage);
+			} else {
+				m_activity.toast(getErrorMessage());
+			}
+			//m_activity.setLoadingStatus(getErrorMessage(), false);
+		} */
+	}
+
+	private int getSkip(boolean append) {
+		int skip = 0;
+
+		if (append) {
+			// adaptive, all_articles, marked, published, unread
+			String viewMode = m_prefs.getString("view_mode", "adaptive");
+
+			int numUnread = Math.toIntExact(m_articles.getUnreadCount());
+			int numAll = Math.toIntExact(m_articles.getSizeWithoutFooters());
+
+			if ("marked".equals(viewMode)) {
+				skip = numAll;
+			} else if ("published".equals(viewMode)) {
+				skip = numAll;
+			} else if ("unread".equals(viewMode)) {
+				skip = numUnread;
+			} else if (m_searchQuery != null && !m_searchQuery.isEmpty()) {
+				skip = numAll;
+			} else if ("adaptive".equals(viewMode)) {
+				skip = numUnread > 0 ? numUnread : numAll;
+			} else {
+				skip = numAll;
+			}
+		}
+
+		return skip;
+	}
+
+	@Override
+	public void setStatusCode(int statusCode) {
+		m_apiStatusCode = statusCode;
+	}
+
+	@Override
+	public void setLastError(ApiError lastError) {
+		m_lastError = lastError;
+	}
+
+	@Override
+	public void setLastErrorMessage(String message) {
+		m_lastErrorMessage = message;
+	}
+
+	public boolean getFirstIdChanged() {
+		return m_firstIdChanged;
+	}
+
+	public boolean getAppend() {
+		return m_append;
+	}
+}
diff --git a/org.fox.ttrss/src/main/java/org/fox/ttrss/types/Article.java b/org.fox.ttrss/src/main/java/org/fox/ttrss/types/Article.java
index 7d476ad6..ec620337 100755
--- a/org.fox.ttrss/src/main/java/org/fox/ttrss/types/Article.java
+++ b/org.fox.ttrss/src/main/java/org/fox/ttrss/types/Article.java
@@ -3,6 +3,8 @@ package org.fox.ttrss.types;
 import android.os.Parcel;
 import android.os.Parcelable;
 
+import androidx.annotation.NonNull;
+
 import org.jsoup.Jsoup;
 import org.jsoup.nodes.Document;
 import org.jsoup.nodes.Element;
@@ -268,7 +270,7 @@ public class Article implements Parcelable {
 			return false;
 		}
 	}
-	
+
 	@SuppressWarnings("rawtypes")
 	public static final Parcelable.Creator CREATOR =
     	new Parcelable.Creator() {