package fr.gouv.etalab.mastodon.fragments;
/* Copyright 2017 Thomas Schneider
 *
 * This file is a part of Mastalab
 *
 * This program is free software; you can redistribute it and/or modify it under the terms of the
 * GNU General Public License as published by the Free Software Foundation; either version 3 of the
 * License, or (at your option) any later version.
 *
 * Mastalab is distributed in the hope that it will be useful, but WITHOUT ANY WARRANTY; without even
 * the implied warranty of MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU General
 * Public License for more details.
 *
 * You should have received a copy of the GNU General Public License along with Mastalab; if not,
 * see <http://www.gnu.org/licenses>. */
import android.content.Context;
import android.content.SharedPreferences;
import android.os.AsyncTask;
import android.os.Bundle;
import android.os.Handler;
import android.os.Looper;
import android.support.annotation.NonNull;
import android.support.v4.app.Fragment;
import android.support.v4.widget.SwipeRefreshLayout;
import android.support.v7.widget.DividerItemDecoration;
import android.support.v7.widget.LinearLayoutManager;
import android.support.v7.widget.RecyclerView;
import android.view.LayoutInflater;
import android.view.View;
import android.view.ViewGroup;
import android.widget.RelativeLayout;
import android.widget.Toast;
import java.util.ArrayList;
import java.util.List;

import fr.gouv.etalab.mastodon.R;
import fr.gouv.etalab.mastodon.activities.MainActivity;
import fr.gouv.etalab.mastodon.asynctasks.RetrieveMissingNotificationsAsyncTask;
import fr.gouv.etalab.mastodon.client.APIResponse;
import fr.gouv.etalab.mastodon.drawers.NotificationsListAdapter;
import fr.gouv.etalab.mastodon.helper.Helper;
import fr.gouv.etalab.mastodon.interfaces.OnRetrieveMissingNotificationsInterface;
import fr.gouv.etalab.mastodon.asynctasks.RetrieveNotificationsAsyncTask;
import fr.gouv.etalab.mastodon.client.Entities.Notification;
import fr.gouv.etalab.mastodon.interfaces.OnRetrieveNotificationsInterface;


/**
 * Created by Thomas on 28/04/2017.
 * Fragment to display notifications related to accounts
 */
public class DisplayNotificationsFragment extends Fragment implements OnRetrieveNotificationsInterface, OnRetrieveMissingNotificationsInterface {



    private boolean flag_loading;
    private Context context;
    private AsyncTask<Void, Void, Void> asyncTask;
    private NotificationsListAdapter notificationsListAdapter;
    private String max_id;
    private List<Notification> notifications;
    private RelativeLayout mainLoader, nextElementLoader, textviewNoAction;
    private boolean firstLoad;
    private SwipeRefreshLayout swipeRefreshLayout;
    private boolean swiped;
    private RecyclerView lv_notifications;
    private String lastReadNotifications;
    private String userId;
    LinearLayoutManager mLayoutManager;

    public DisplayNotificationsFragment(){
    }

    @Override
    public View onCreateView(@NonNull LayoutInflater inflater, ViewGroup container, Bundle savedInstanceState) {

        View rootView = inflater.inflate(R.layout.fragment_notifications, container, false);
        max_id = null;
        context = getContext();
        firstLoad = true;
        flag_loading = true;
        notifications = new ArrayList<>();
        swiped = false;

        swipeRefreshLayout = rootView.findViewById(R.id.swipeContainer);
        final SharedPreferences sharedpreferences = context.getSharedPreferences(Helper.APP_PREFS, Context.MODE_PRIVATE);
        lv_notifications = rootView.findViewById(R.id.lv_notifications);
        lv_notifications.addItemDecoration(new DividerItemDecoration(context, DividerItemDecoration.VERTICAL));
        mainLoader = rootView.findViewById(R.id.loader);
        nextElementLoader = rootView.findViewById(R.id.loading_next_notifications);
        textviewNoAction = rootView.findViewById(R.id.no_action);
        mainLoader.setVisibility(View.VISIBLE);
        nextElementLoader.setVisibility(View.GONE);
        boolean isOnWifi = Helper.isOnWIFI(context);
        int behaviorWithAttachments = sharedpreferences.getInt(Helper.SET_ATTACHMENT_ACTION, Helper.ATTACHMENT_ALWAYS);
        userId = sharedpreferences.getString(Helper.PREF_KEY_ID, null);
        lastReadNotifications = sharedpreferences.getString(Helper.LAST_NOTIFICATION_MAX_ID + userId, null);
        notificationsListAdapter = new NotificationsListAdapter(context,isOnWifi, behaviorWithAttachments,this.notifications);
        lv_notifications.setAdapter(notificationsListAdapter);
        mLayoutManager = new LinearLayoutManager(context);
        lv_notifications.setLayoutManager(mLayoutManager);
        lv_notifications.addOnScrollListener(new RecyclerView.OnScrollListener() {
            public void onScrolled(RecyclerView recyclerView, int dx, int dy)
            {
                if(dy > 0) {
                    int visibleItemCount = mLayoutManager.getChildCount();
                    int totalItemCount = mLayoutManager.getItemCount();
                    int firstVisibleItem = mLayoutManager.findFirstVisibleItemPosition();
                    if (firstVisibleItem + visibleItemCount == totalItemCount && context != null) {
                        if (!flag_loading) {
                            flag_loading = true;
                            asyncTask = new RetrieveNotificationsAsyncTask(context, true, null, null, max_id, null, null, DisplayNotificationsFragment.this).executeOnExecutor(AsyncTask.THREAD_POOL_EXECUTOR);
                            nextElementLoader.setVisibility(View.VISIBLE);
                        }
                    } else {
                        nextElementLoader.setVisibility(View.GONE);
                    }
                }
            }
        });

        swipeRefreshLayout.setOnRefreshListener(new SwipeRefreshLayout.OnRefreshListener() {
            @Override
            public void onRefresh() {
                max_id = null;
                notifications = new ArrayList<>();
                firstLoad = true;
                flag_loading = true;
                swiped = true;
                MainActivity.countNewNotifications = 0;
                if( context != null)
                    asyncTask = new RetrieveNotificationsAsyncTask(context, true, null, null, max_id, null, null, DisplayNotificationsFragment.this).executeOnExecutor(AsyncTask.THREAD_POOL_EXECUTOR);
            }
        });
        swipeRefreshLayout.setColorSchemeResources(R.color.mastodonC4,
                R.color.mastodonC2,
                R.color.mastodonC3);
        if( context != null)
            asyncTask = new RetrieveNotificationsAsyncTask(context, true, null, null, max_id, null, null, DisplayNotificationsFragment.this).executeOnExecutor(AsyncTask.THREAD_POOL_EXECUTOR);
        else
            new Handler(Looper.getMainLooper()).postDelayed(new Runnable() {
                @Override
                public void run() {
                    if( context != null)
                        asyncTask = new RetrieveNotificationsAsyncTask(context, true, null, null, max_id, null, null, DisplayNotificationsFragment.this).executeOnExecutor(AsyncTask.THREAD_POOL_EXECUTOR);
                }
            }, 500);
        return rootView;
    }



    @Override
    public void onCreate(Bundle saveInstance)
    {
        super.onCreate(saveInstance);
    }



    @Override
    public void onAttach(Context context) {
        super.onAttach(context);
        this.context = context;
    }

    public void onDestroy() {
        super.onDestroy();
        if(asyncTask != null && asyncTask.getStatus() == AsyncTask.Status.RUNNING)
            asyncTask.cancel(true);
    }

    @Override
    public void onRetrieveNotifications(APIResponse apiResponse, String acct, String userId, boolean refreshData) {
        final SharedPreferences sharedpreferences = context.getSharedPreferences(Helper.APP_PREFS, Context.MODE_PRIVATE);
        mainLoader.setVisibility(View.GONE);
        nextElementLoader.setVisibility(View.GONE);
        if( apiResponse.getError() != null){
            boolean show_error_messages = sharedpreferences.getBoolean(Helper.SET_SHOW_ERROR_MESSAGES, true);
            if( show_error_messages)
                Toast.makeText(context, apiResponse.getError().getError(),Toast.LENGTH_LONG).show();
            flag_loading = false;
            swipeRefreshLayout.setRefreshing(false);
            swiped = false;
            return;
        }
        int previousPosition = notifications.size();
        max_id = apiResponse.getMax_id();
        List<Notification> notifications = apiResponse.getNotifications();

        if( !swiped && firstLoad && (notifications == null || notifications.size() == 0))
            textviewNoAction.setVisibility(View.VISIBLE);
        else
            textviewNoAction.setVisibility(View.GONE);
        if( swiped ){
            boolean isOnWifi = Helper.isOnWIFI(context);
            int behaviorWithAttachments = sharedpreferences.getInt(Helper.SET_ATTACHMENT_ACTION, Helper.ATTACHMENT_ALWAYS);
            notificationsListAdapter = new NotificationsListAdapter(context,isOnWifi, behaviorWithAttachments, this.notifications);
            lv_notifications.setAdapter(notificationsListAdapter);
            swiped = false;
        }

        if( notifications != null && notifications.size() > 0) {
            for(Notification tmpNotification: notifications){
                if( lastReadNotifications != null && Long.parseLong(tmpNotification.getId()) > Long.parseLong(lastReadNotifications)) {
                    MainActivity.countNewNotifications++;
                }
                this.notifications.add(tmpNotification);
            }
            if( firstLoad) {
                //Update the id of the last notification retrieved
                MainActivity.lastNotificationId = notifications.get(0).getId();
                updateNotificationLastId(sharedpreferences, this.userId, notifications.get(0).getId());
            }
            notificationsListAdapter.notifyItemRangeInserted(previousPosition, notifications.size());
        }
        if( firstLoad )
            ((MainActivity)context).updateNotifCounter();
        swipeRefreshLayout.setRefreshing(false);
        firstLoad = false;
        //The initial call comes from a classic tab refresh
        flag_loading = (max_id == null );
    }

    /**
     * Called from main activity in onResume to retrieve missing notifications
     * @param sinceId String
     */
    public void retrieveMissingNotifications(String sinceId){
        asyncTask = new RetrieveMissingNotificationsAsyncTask(context, sinceId, DisplayNotificationsFragment.this).executeOnExecutor(AsyncTask.THREAD_POOL_EXECUTOR);
    }

    @Override
    public void setMenuVisibility(final boolean visible) {
        super.setMenuVisibility(visible);
        if( context == null)
            return;
        //Store last notification id to avoid to notify for those that have been already seen
        SharedPreferences sharedpreferences = context.getSharedPreferences(Helper.APP_PREFS, Context.MODE_PRIVATE);
        if (visible && notifications != null && notifications.size() > 0) {
            updateNotificationLastId(sharedpreferences, this.userId, notifications.get(0).getId());
        }
    }

    public void scrollToTop(){
        if( lv_notifications != null)
            lv_notifications.setAdapter(notificationsListAdapter);
        //Store last toot id for home timeline to avoid to notify for those that have been already seen
        //Store last notification id to avoid to notify for those that have been already seen
        SharedPreferences sharedpreferences = context.getSharedPreferences(Helper.APP_PREFS, Context.MODE_PRIVATE);
        if (notifications != null && notifications.size() > 0) {
            updateNotificationLastId(sharedpreferences, this.userId, notifications.get(0).getId());
        }
    }

    public void refreshAll(){
        if( context == null)
            return;
        max_id = null;
        notifications = new ArrayList<>();
        firstLoad = true;
        flag_loading = true;
        swiped = true;
        MainActivity.countNewNotifications = 0;
        if( context != null)
            asyncTask = new RetrieveNotificationsAsyncTask(context, true, null, null, max_id, null, null, DisplayNotificationsFragment.this).executeOnExecutor(AsyncTask.THREAD_POOL_EXECUTOR);
        else {
            new Handler(Looper.getMainLooper()).postDelayed(new Runnable() {
                @Override
                public void run() {
                    if( context != null){
                        asyncTask = new RetrieveNotificationsAsyncTask(context, true, null, null, max_id, null, null, DisplayNotificationsFragment.this).executeOnExecutor(AsyncTask.THREAD_POOL_EXECUTOR);
                    }
                }
            }, 500);
        }
    }


    public void refresh(Notification notification){
        if( context == null)
            return;
        if( notification != null){
            //Makes sure the notifications is not already displayed
            if( notification.getId() != null && notifications != null && notifications.size() > 0 && notifications.get(0)!= null
                    && Long.parseLong(notification.getId()) > Long.parseLong(notifications.get(0).getId())) {
                //Update the id of the last notification retrieved
                MainActivity.lastNotificationId = notification.getId();
                notifications.add(0, notification);
                MainActivity.countNewNotifications++;
                int firstVisibleItem = mLayoutManager.findFirstVisibleItemPosition();
                if (firstVisibleItem > 0)
                    notificationsListAdapter.notifyItemInserted(0);
                else
                    notificationsListAdapter.notifyDataSetChanged();
                if (textviewNoAction.getVisibility() == View.VISIBLE)
                    textviewNoAction.setVisibility(View.GONE);
            }
        }
    }



    @Override
    public void onRetrieveMissingNotifications(List<Notification> notifications) {
        if( notifications != null && notifications.size() > 0) {
            for (int i = notifications.size()-1 ; i >= 0 ; i--) {
                if (this.notifications.size() == 0 ||
                        Long.parseLong(notifications.get(i).getId()) > Long.parseLong(this.notifications.get(0).getId())) {
                    MainActivity.countNewNotifications++;
                    this.notifications.add(0, notifications.get(i));
                }
            }
            notificationsListAdapter.notifyDataSetChanged();
            try {
                ((MainActivity) context).updateNotifCounter();
            }catch (Exception ignored){}
        }
    }

    /**
     * Records the id of the notification only if its greater than the previous one.
     * @param sharedPreferences SharedPreferences
     * @param userId String current logged user
     * @param notificationId String current notification id to check
     */
    private void updateNotificationLastId(SharedPreferences sharedPreferences, String userId, String notificationId){
        String lastNotif = sharedPreferences.getString(Helper.LAST_NOTIFICATION_MAX_ID + userId, null);
        if( lastNotif != null && notificationId != null && Long.parseLong(notificationId) > Long.parseLong(lastNotif)){
            SharedPreferences.Editor editor = sharedPreferences.edit();
            editor.putString(Helper.LAST_NOTIFICATION_MAX_ID + userId, notificationId);
            editor.apply();
            lastReadNotifications = notificationId;
        }
    }
}