MeteoSystem/app/src/main/java/cc/pogoda/mobile/meteosystem/adapter/WeatherStationRecyclerViewAdapter.java

package cc.pogoda.mobile.meteosystem.adapter;

import android.content.Context;
import android.os.Handler;
import android.os.Looper;
import android.util.TypedValue;
import android.view.LayoutInflater;
import android.view.View;
import android.view.ViewGroup;
import android.widget.Button;
import android.widget.TextView;

import androidx.annotation.NonNull;
import androidx.appcompat.app.AppCompatActivity;
import androidx.recyclerview.widget.RecyclerView;

import java.util.List;

import cc.pogoda.mobile.meteosystem.Main;
import cc.pogoda.mobile.meteosystem.R;
import cc.pogoda.mobile.meteosystem.activity.handler.AllStationsActRecyclerViewButtonClickEvent;
import cc.pogoda.mobile.meteosystem.activity.updater.FavouritesStationDetailsOnListUpdater;
import cc.pogoda.mobile.meteosystem.activity.view.AllStationsActRecyclerViewHolder;
import cc.pogoda.mobile.meteosystem.dao.AvailableParametersDao;
import cc.pogoda.mobile.meteosystem.dao.SummaryDao;
import cc.pogoda.mobile.meteosystem.type.ParceableFavsCallReason;
import cc.pogoda.mobile.meteosystem.type.WeatherStation;

public class WeatherStationRecyclerViewAdapter extends RecyclerView.Adapter<RecyclerView.ViewHolder> {

    final private List<WeatherStation> stations;

    AppCompatActivity activity;

    ParceableFavsCallReason.Reason reason;

    /**
     * This updater takes data stored in the hashmap and then updates TextViews on View Holders on
     * Favourites list
     */
    private FavouritesStationDetailsOnListUpdater favsUpdater = null;

    Handler handler = null;

    /**
     * This instance of 'Main' singleton class is used to obtain HashMap<String, Summary> stationSystemNameToSummary
     */
    Main main;

    private static final int VIEW_TYPE_EMPTY_LIST = 0;
    private static final int VIEW_TYPE_OBJECT = 1;

    public WeatherStationRecyclerViewAdapter(
            List<WeatherStation> stations,
            AppCompatActivity parentActivity,
            ParceableFavsCallReason.Reason callReason) {
        this.stations = stations;
        this.activity = parentActivity;
        this.reason = callReason;
        this.main = (Main) parentActivity.getApplication();
    }

    @NonNull
    @Override
    public RecyclerView.ViewHolder onCreateViewHolder(@NonNull ViewGroup parent, int viewType) {
        Context context = parent.getContext();
        LayoutInflater inflater = LayoutInflater.from(context);
        View view;

        switch (viewType){
            case VIEW_TYPE_OBJECT:
                // check the call reason
                if (reason.equals(ParceableFavsCallReason.Reason.FAVOURITES)) {
                    // inflate custom layout
                    view = inflater.inflate(R.layout.activity_favourites_linear_layout_data,
                            parent, false);
                }
                else {
                    // Inflate the custom layout without current data
                    view = inflater.inflate(R.layout.activity_all_stations_linear_layout,
                            parent, false);
                }
                return new AllStationsActRecyclerViewHolder(view, reason);

            case VIEW_TYPE_EMPTY_LIST:
            default:
                if (reason.equals(ParceableFavsCallReason.Reason.FAVOURITES)) {
                    view = inflater.inflate(R.layout.activity_favourites_empty, parent,
                            false);
                } else {
                    view = inflater.inflate(R.layout.activity_all_stations_empty, parent,
                            false);
                }
                return new EmptyViewHolder(view);
        }
    }

    @Override
    public int getItemViewType(int position) {
        if (stations.isEmpty()) {
            return VIEW_TYPE_EMPTY_LIST;
        } else {
            return VIEW_TYPE_OBJECT;
        }
    }

    @Override
    public void onBindViewHolder(@NonNull RecyclerView.ViewHolder viewHolder, int position) {

        if(viewHolder instanceof AllStationsActRecyclerViewHolder) {
            AllStationsActRecyclerViewHolder holder =
                    (AllStationsActRecyclerViewHolder) viewHolder;

            // this TextView shows the station name
            TextView textView = holder.textView;

            // this TextView shows station data if this is favourites list
            TextView textViewData = holder.textViewData;

            // button to go to the StationDetailsActivity
            Button button = holder.button;

            // get the station object from a list of either all stations or favourites
            WeatherStation station = stations.get(position);

            if (station != null) {
                textView.setText(station.getDisplayedName());
                button.setText(R.string.select_station);

                if (station.getDisplayedName().length() > 22) {
                    textView.setTextSize(TypedValue.COMPLEX_UNIT_SP, 20.0f);
                } else {
                    textView.setTextSize(TypedValue.COMPLEX_UNIT_SP, 22.0f);
                }

                button.setOnClickListener(new AllStationsActRecyclerViewButtonClickEvent(station, activity, reason));
            }

            // this if distinguish between All Stations and Favorites view
            if (textViewData != null && favsUpdater != null) {

                favsUpdater.addNewStation(station.getSystemName(), textViewData);
            }
        }
    }

    @Override
    public int getItemCount() {
        // In case of empty station list at least 1 should be returned to properly select view type
        // and render empty list info.
        return stations.isEmpty() ?  1 : stations.size();
    }

    public void createAndStartUpdater() {

        // check if there is previous instance of updater
        if (favsUpdater != null && favsUpdater.isEnabled()) {
            stopUpdater();
        }

        handler = new Handler(Looper.getMainLooper());
        favsUpdater = new FavouritesStationDetailsOnListUpdater(handler, main.getHashmapFavStationSystemNameToSummary(), main.getHashmapAllStationSystemNameToAvailParameters());

        handler.postDelayed(favsUpdater, 100);
        favsUpdater.setEnabled(true);
    }

    public void stopUpdater() {
        if (reason.equals(ParceableFavsCallReason.Reason.FAVOURITES)
                && handler != null && favsUpdater != null) {
            handler.removeCallbacks(favsUpdater);
            favsUpdater.setEnabled(false);
        }
    }


    private class EmptyViewHolder extends RecyclerView.ViewHolder{

        public EmptyViewHolder(@NonNull View itemView) {
            super(itemView);
        }
    }

}