package com.limelight.preferences;

import java.net.Inet4Address;
import java.net.InetAddress;
import java.net.InterfaceAddress;
import java.net.NetworkInterface;
import java.net.SocketException;
import java.net.UnknownHostException;
import java.util.Collections;
import java.util.concurrent.LinkedBlockingQueue;

import com.limelight.computers.ComputerManagerService;
import com.limelight.R;
import com.limelight.utils.Dialog;
import com.limelight.utils.SpinnerDialog;
import com.limelight.utils.UiHelper;

import android.app.Activity;
import android.app.Service;
import android.content.ComponentName;
import android.content.Context;
import android.content.Intent;
import android.content.ServiceConnection;
import android.os.Bundle;
import android.os.IBinder;
import android.view.KeyEvent;
import android.view.inputmethod.EditorInfo;
import android.view.inputmethod.InputMethodManager;
import android.widget.TextView;
import android.widget.Toast;

public class AddComputerManually extends Activity {
    private TextView hostText;
    private ComputerManagerService.ComputerManagerBinder managerBinder;
    private final LinkedBlockingQueue<String> computersToAdd = new LinkedBlockingQueue<>();
    private Thread addThread;
    private final ServiceConnection serviceConnection = new ServiceConnection() {
        public void onServiceConnected(ComponentName className, final IBinder binder) {
            managerBinder = ((ComputerManagerService.ComputerManagerBinder)binder);
            startAddThread();
        }

        public void onServiceDisconnected(ComponentName className) {
            joinAddThread();
            managerBinder = null;
        }
    };

    private boolean isWrongSubnetSiteLocalAddress(String address) {
        try {
            InetAddress targetAddress = InetAddress.getByName(address);
            if (!(targetAddress instanceof Inet4Address) || !targetAddress.isSiteLocalAddress()) {
                return false;
            }

            // We have a site-local address. Look for a matching local interface.
            for (NetworkInterface iface : Collections.list(NetworkInterface.getNetworkInterfaces())) {
                for (InterfaceAddress addr : iface.getInterfaceAddresses()) {
                    if (!(addr.getAddress() instanceof Inet4Address) || !addr.getAddress().isSiteLocalAddress()) {
                        // Skip non-site-local or non-IPv4 addresses
                        continue;
                    }

                    byte[] targetAddrBytes = targetAddress.getAddress();
                    byte[] ifaceAddrBytes = addr.getAddress().getAddress();

                    // Compare prefix to ensure it's the same
                    boolean addressMatches = true;
                    for (int i = 0; i < addr.getNetworkPrefixLength(); i++) {
                        if ((ifaceAddrBytes[i / 8] & (1 << (i % 8))) != (targetAddrBytes[i / 8] & (1 << (i % 8)))) {
                            addressMatches = false;
                            break;
                        }
                    }

                    if (addressMatches) {
                        return false;
                    }
                }
            }

            // Couldn't find a matching interface
            return true;
        } catch (SocketException e) {
            e.printStackTrace();
            return false;
        } catch (UnknownHostException e) {
            return false;
        }
    }

    private void doAddPc(String host) {
        String msg;
        boolean wrongSiteLocal = false;
        boolean success;

        SpinnerDialog dialog = SpinnerDialog.displayDialog(this, getResources().getString(R.string.title_add_pc),
            getResources().getString(R.string.msg_add_pc), false);

        success = managerBinder.addComputerBlocking(host, true);
        if (!success){
            wrongSiteLocal = isWrongSubnetSiteLocalAddress(host);
        }

        dialog.dismiss();

        if (wrongSiteLocal) {
            Dialog.displayDialog(this, getResources().getString(R.string.conn_error_title), getResources().getString(R.string.addpc_wrong_sitelocal), false);
        }
        else if (!success) {
            Dialog.displayDialog(this, getResources().getString(R.string.conn_error_title), getResources().getString(R.string.addpc_fail), false);
        }
        else {
            AddComputerManually.this.runOnUiThread(new Runnable() {
                @Override
                public void run() {
                Toast.makeText(AddComputerManually.this, getResources().getString(R.string.addpc_success), Toast.LENGTH_LONG).show();

                if (!isFinishing()) {
                    // Close the activity
                    AddComputerManually.this.finish();
                }
                }
            });
        }

    }

    private void startAddThread() {
        addThread = new Thread() {
            @Override
            public void run() {
                while (!isInterrupted()) {
                    String computer;

                    try {
                        computer = computersToAdd.take();
                    } catch (InterruptedException e) {
                        return;
                    }

                    doAddPc(computer);
                }
            }
        };
        addThread.setName("UI - AddComputerManually");
        addThread.start();
    }

    private void joinAddThread() {
        if (addThread != null) {
            addThread.interrupt();

            try {
                addThread.join();
            } catch (InterruptedException ignored) {}

            addThread = null;
        }
    }

    @Override
    protected void onStop() {
        super.onStop();

        Dialog.closeDialogs();
        SpinnerDialog.closeDialogs(this);
    }

    @Override
    protected void onDestroy() {
        super.onDestroy();

        if (managerBinder != null) {
            joinAddThread();
            unbindService(serviceConnection);
        }
    }

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

        UiHelper.setLocale(this);

        setContentView(R.layout.activity_add_computer_manually);

        UiHelper.notifyNewRootView(this);

        this.hostText = findViewById(R.id.hostTextView);
        hostText.setImeOptions(EditorInfo.IME_ACTION_DONE);
        hostText.setOnEditorActionListener(new TextView.OnEditorActionListener() {
            @Override
            public boolean onEditorAction(TextView textView, int actionId, KeyEvent keyEvent) {
                if (actionId == EditorInfo.IME_ACTION_DONE ||
                        (keyEvent != null &&
                                keyEvent.getAction() == KeyEvent.ACTION_DOWN &&
                                keyEvent.getKeyCode() == KeyEvent.KEYCODE_ENTER)) {
                    if (hostText.getText().length() == 0) {
                        Toast.makeText(AddComputerManually.this, getResources().getString(R.string.addpc_enter_ip), Toast.LENGTH_LONG).show();
                        return true;
                    }

                    computersToAdd.add(hostText.getText().toString().trim());
                }
                else if (actionId == EditorInfo.IME_ACTION_PREVIOUS) {
                    // This is how the Fire TV dismisses the keyboard
                    InputMethodManager imm = (InputMethodManager)getSystemService(Context.INPUT_METHOD_SERVICE);
                    imm.hideSoftInputFromWindow(hostText.getWindowToken(), 0);
                    return false;
                }

                return false;
            }
        });

        // Bind to the ComputerManager service
        bindService(new Intent(AddComputerManually.this,
                    ComputerManagerService.class), serviceConnection, Service.BIND_AUTO_CREATE);
    }
}