package com.javispedro.rempe;

import android.content.SharedPreferences;
import android.os.Bundle;
import android.util.Log;
import android.view.Menu;
import android.view.MenuItem;

import androidx.annotation.Nullable;
import androidx.appcompat.app.AppCompatActivity;
import androidx.appcompat.widget.Toolbar;
import androidx.preference.PreferenceManager;
import androidx.recyclerview.widget.DiffUtil;
import androidx.recyclerview.widget.LinearLayoutManager;
import androidx.recyclerview.widget.ListUpdateCallback;
import androidx.recyclerview.widget.RecyclerView;

import com.dsi.ant.plugins.antplus.pcc.AntPlusEnvironmentPcc;
import com.dsi.ant.plugins.antplus.pcc.defines.DeviceState;
import com.dsi.ant.plugins.antplus.pcc.defines.RequestAccessResult;
import com.dsi.ant.plugins.antplus.pccbase.AntPluginPcc;
import com.dsi.ant.plugins.antplus.pccbase.PccReleaseHandle;
import com.google.android.material.floatingactionbutton.FloatingActionButton;
import com.google.android.material.snackbar.Snackbar;

import java.util.ArrayList;
import java.util.List;

public class MainActivity extends AppCompatActivity {
    private final static String TAG = "MainActivity";

    private SharedPreferences mPrefs = null;
    private SharedPreferences.OnSharedPreferenceChangeListener mPrefsListener = new SharedPreferences.OnSharedPreferenceChangeListener() {
        @Override
        public void onSharedPreferenceChanged(SharedPreferences sharedPreferences, String key) {
            switch (key) {
                case Preferences.PREFS_DEVICES:
                    refreshDevices();
                    break;
            }
        }
    };

    private final ArrayList<Integer> mDeviceNumbers = new ArrayList<Integer>();
    private final ArrayList<Device> mDevices = new ArrayList<Device>();

    private DeviceListRecyclerViewListAdapter mDeviceListAdapter;

    private PccReleaseHandle<AntPlusEnvironmentPcc> mPccSearchHandle;

    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);

        mPrefs = PreferenceManager.getDefaultSharedPreferences(this);

        setContentView(R.layout.activity_main);
        Toolbar toolbar = findViewById(R.id.toolbar);
        setSupportActionBar(toolbar);

        FloatingActionButton fab = findViewById(R.id.fabAddDevice);
        fab.setOnClickListener(view -> onConnectButtonClicked());

        RecyclerView list = findViewById(R.id.list);
        list.setLayoutManager(new LinearLayoutManager(list.getContext()));
        mDeviceListAdapter = new DeviceListRecyclerViewListAdapter();
        list.setAdapter(mDeviceListAdapter);

        refreshDevices();
    }

    @Override
    protected void onDestroy() {
        disconnectAll();
        mPrefs = null;
        mDeviceListAdapter = null;
        super.onDestroy();
    }

    @Override
    public void onResume() {
        super.onResume();
        mPrefs.registerOnSharedPreferenceChangeListener(mPrefsListener);
        connectToDevices();
    }

    @Override
    public void onPause() {
        disconnectAll();
        mPrefs.unregisterOnSharedPreferenceChangeListener(mPrefsListener);
        super.onPause();
    }

    @Override
    public boolean onCreateOptionsMenu(Menu menu) {
        // Inflate the menu; this adds items to the action bar if it is present.
        getMenuInflater().inflate(R.menu.menu_main, menu);
        return true;
    }

    @Override
    public boolean onOptionsItemSelected(MenuItem item) {
        // Handle action bar item clicks here. The action bar will
        // automatically handle clicks on the Home/Up button, so long
        // as you specify a parent activity in AndroidManifest.xml.
        int id = item.getItemId();

        switch (id) {
            case R.id.action_remove_all:
                removeAllDevices();
                return true;
            case R.id.action_settings:
                return true;
        }

        return super.onOptionsItemSelected(item);
    }

    private void onConnectButtonClicked() {
        searchForNewDevice();
    }

    public void searchForNewDevice() {
        Log.d(TAG, "searchForNewDevice");
        if (mPccSearchHandle != null) {
            mPccSearchHandle.close();
            mPccSearchHandle = null;
        }
        mPccSearchHandle = AntPlusEnvironmentPcc.requestAccess(this, this, mResultReceiver, mDeviceStateChangeReceiver);
    }

    private AntPluginPcc.IPluginAccessResultReceiver<AntPlusEnvironmentPcc> mResultReceiver = new AntPluginPcc.IPluginAccessResultReceiver<AntPlusEnvironmentPcc>() {
        @Override
        public void onResultReceived(AntPlusEnvironmentPcc result, RequestAccessResult resultCode, DeviceState initialDeviceState) {
            Log.d(TAG, "onResultReceived resultCode=" + resultCode);
            if (resultCode == RequestAccessResult.SUCCESS) {
                int deviceNumber = result.getAntDeviceNumber();
                result.releaseAccess();
                runOnUiThread(() -> addDevice(result.getAntDeviceNumber()));
            } else if (resultCode != RequestAccessResult.USER_CANCELLED) {
                runOnUiThread(() -> {
                    final String resultText = Device.connectionRequestAccessResultToString(MainActivity.this, resultCode);
                    Snackbar.make(findViewById(R.id.fabAddDevice),
                            getString(R.string.add_device_failed, resultText), Snackbar.LENGTH_INDEFINITE).show();
                });
            }
            mPccSearchHandle.close();
            mPccSearchHandle = null;
        }
    };

    private AntPluginPcc.IDeviceStateChangeReceiver mDeviceStateChangeReceiver = new AntPluginPcc.IDeviceStateChangeReceiver() {
        @Override
        public void onDeviceStateChange(DeviceState newDeviceState) {
            Log.d(TAG, "onDeviceStateChange newDeviceState=" + newDeviceState);
        }
    };

    public void addDevice(int deviceNumber) {
        Log.d(TAG, "addDevice " + deviceNumber);
        List<Integer> list = Preferences.getDeviceNumbers(mPrefs);
        if (list.contains(deviceNumber)) {
            Snackbar.make(findViewById(R.id.fabAddDevice),
                    getString(R.string.add_device_already), Snackbar.LENGTH_INDEFINITE).show();
            return;
        }
        list.add(deviceNumber);
        Preferences.saveDeviceNumbers(mPrefs, list);
    }

    public void removeAllDevices() {
        List<Integer> list = new ArrayList<Integer>();
        Preferences.saveDeviceNumbers(mPrefs, list);
    }

    public void refreshDevices() {
        Log.d(TAG, "refreshDevices");

        setDeviceNumberList(Preferences.getDeviceNumbers(mPrefs));
    }

    public void connectToDevices() {
        Log.d(TAG, "connectToDevices");
        for (Device dev : mDevices) {
            if (!dev.isOpen()) {
                dev.connect(this);
            }
        }
    }

    public void disconnectAll() {
        Log.d(TAG, "disconnectAll");
        for (Device dev : mDevices) {
            dev.close();
        }
    }

    void setDeviceNumberList(List<Integer> newDeviceNumbers) {
            DiffUtil.DiffResult diff = DiffUtil.calculateDiff(new DiffUtil.Callback() {
            @Override
            public int getOldListSize() {
                return mDeviceNumbers.size();
            }

            @Override
            public int getNewListSize() {
                return newDeviceNumbers.size();
            }

            @Override
            public boolean areItemsTheSame(int oldItemPosition, int newItemPosition) {
                return mDeviceNumbers.get(oldItemPosition).equals(newDeviceNumbers.get(newItemPosition));
            }

            @Override
            public boolean areContentsTheSame(int oldItemPosition, int newItemPosition) {
                return areItemsTheSame(oldItemPosition, newItemPosition);
            }
        });

        diff.dispatchUpdatesTo(new ListUpdateCallback() {
            @Override
            public void onInserted(int position, int count) {
                for (int i = 0; i < count; ++i) {
                    final int deviceNumber = newDeviceNumbers.get(position + i);
                    Device device = new Device(deviceNumber);
                    mDeviceNumbers.add(position + i, deviceNumber);
                    mDevices.add(position + i, device);
                }
            }

            @Override
            public void onRemoved(int position, int count) {
                for (int i = 0; i < count; ++i) {
                    mDevices.get(position + i).close();
                }
                mDevices.subList(position, position + count).clear();
                mDeviceNumbers.subList(position, position + count).clear();
            }

            @Override
            public void onMoved(int fromPosition, int toPosition) {
                mDevices.set(toPosition, mDevices.get(fromPosition));
                mDevices.set(fromPosition, null);
                mDeviceNumbers.set(toPosition, mDeviceNumbers.get(fromPosition));
                mDeviceNumbers.set(fromPosition, 0);
            }

            @Override
            public void onChanged(int position, int count, @Nullable Object payload) {
                // Nothing to be done
            }
        });

        if (mDeviceListAdapter != null) {
            mDeviceListAdapter.setDeviceList(mDevices);
            diff.dispatchUpdatesTo(mDeviceListAdapter);
        }
    }

    public List<Integer> getDeviceNumberList() {
        return mDeviceNumbers;
    }
}