NewPipe/app/src/main/java/org/schabi/newpipe/fragments/local/BaseLocalListFragment.java

package org.schabi.newpipe.fragments.local;

import android.content.Context;
import android.os.Bundle;
import android.support.annotation.NonNull;
import android.support.v7.app.ActionBar;
import android.support.v7.widget.LinearLayoutManager;
import android.support.v7.widget.RecyclerView;
import android.util.Log;
import android.view.Menu;
import android.view.MenuInflater;
import android.view.View;

import org.schabi.newpipe.R;
import org.schabi.newpipe.database.LocalItem;
import org.schabi.newpipe.fragments.BaseStateFragment;
import org.schabi.newpipe.fragments.list.ListViewContract;
import org.schabi.newpipe.util.StateSaver;

import java.util.List;
import java.util.Queue;

import static org.schabi.newpipe.util.AnimationUtils.animateView;

public abstract class BaseLocalListFragment<I, N> extends BaseStateFragment<I>
        implements ListViewContract<I, N>, StateSaver.WriteRead {

    /*//////////////////////////////////////////////////////////////////////////
    // Views
    //////////////////////////////////////////////////////////////////////////*/

    protected LocalItemListAdapter itemListAdapter;
    protected RecyclerView itemsList;

    /*//////////////////////////////////////////////////////////////////////////
    // LifeCycle
    //////////////////////////////////////////////////////////////////////////*/

    @Override
    public void onAttach(Context context) {
        super.onAttach(context);
        itemListAdapter = new LocalItemListAdapter(activity);
    }

    @Override
    public void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setHasOptionsMenu(true);
    }

    @Override
    public void onDestroy() {
        super.onDestroy();
        StateSaver.onDestroy(savedState);
    }

    /*//////////////////////////////////////////////////////////////////////////
    // State Saving
    //////////////////////////////////////////////////////////////////////////*/

    protected StateSaver.SavedState savedState;

    @Override
    public String generateSuffix() {
        // Naive solution, but it's good for now (the items don't change)
        return "." + itemListAdapter.getItemsList().size() + ".list";
    }

    @Override
    public void writeTo(Queue<Object> objectsToSave) {
        objectsToSave.add(itemListAdapter.getItemsList());
    }

    @Override
    @SuppressWarnings("unchecked")
    public void readFrom(@NonNull Queue<Object> savedObjects) throws Exception {
        itemListAdapter.getItemsList().clear();
        itemListAdapter.getItemsList().addAll((List<LocalItem>) savedObjects.poll());
    }

    @Override
    public void onSaveInstanceState(Bundle bundle) {
        super.onSaveInstanceState(bundle);
        savedState = StateSaver.tryToSave(activity.isChangingConfigurations(), savedState, bundle, this);
    }

    @Override
    protected void onRestoreInstanceState(@NonNull Bundle bundle) {
        super.onRestoreInstanceState(bundle);
        savedState = StateSaver.tryToRestore(bundle, this);
    }

    /*//////////////////////////////////////////////////////////////////////////
    // Init
    //////////////////////////////////////////////////////////////////////////*/

    protected View getListHeader() {
        return null;
    }

    protected View getListFooter() {
        return activity.getLayoutInflater().inflate(R.layout.pignate_footer, itemsList, false);
    }

    protected RecyclerView.LayoutManager getListLayoutManager() {
        return new LinearLayoutManager(activity);
    }

    @Override
    protected void initViews(View rootView, Bundle savedInstanceState) {
        super.initViews(rootView, savedInstanceState);

        itemsList = rootView.findViewById(R.id.items_list);
        itemsList.setLayoutManager(getListLayoutManager());

        itemListAdapter.setFooter(getListFooter());
        itemListAdapter.setHeader(getListHeader());

        itemsList.setAdapter(itemListAdapter);
    }

    @Override
    protected void initListeners() {
        super.initListeners();
    }

    /*//////////////////////////////////////////////////////////////////////////
    // Menu
    //////////////////////////////////////////////////////////////////////////*/

    @Override
    public void onCreateOptionsMenu(Menu menu, MenuInflater inflater) {
        if (DEBUG) Log.d(TAG, "onCreateOptionsMenu() called with: menu = [" + menu + "], inflater = [" + inflater + "]");
        super.onCreateOptionsMenu(menu, inflater);
        ActionBar supportActionBar = activity.getSupportActionBar();
        if (supportActionBar != null) {
            supportActionBar.setDisplayShowTitleEnabled(true);
            if(useAsFrontPage) {
                supportActionBar.setDisplayHomeAsUpEnabled(false);
            } else {
                supportActionBar.setDisplayHomeAsUpEnabled(true);
            }
        }
    }

    /*//////////////////////////////////////////////////////////////////////////
    // Contract
    //////////////////////////////////////////////////////////////////////////*/

    @Override
    public void showLoading() {
        super.showLoading();
        // animateView(itemsList, false, 400);
    }

    @Override
    public void hideLoading() {
        super.hideLoading();
        animateView(itemsList, true, 300);
    }

    @Override
    public void showError(String message, boolean showRetryButton) {
        super.showError(message, showRetryButton);
        showListFooter(false);
        animateView(itemsList, false, 200);
    }

    @Override
    public void showEmptyState() {
        super.showEmptyState();
        showListFooter(false);
    }

    @Override
    public void showListFooter(final boolean show) {
        itemsList.post(() -> itemListAdapter.showFooter(show));
    }

    @Override
    public void handleNextItems(N result) {
        isLoading.set(false);
    }
}