PreferenceManager preferenceManager;
LinearLayout Layout_bars;
TextView[] bottomBars;
TextView txt_login;
int[] screens;
Button signup;
ViewPager vp;
MyViewPagerAdapter myvpAdapter;
String TAG = "MainScreen";


@Override
protected void onCreate(Bundle savedInstanceState) {
    super.onCreate(savedInstanceState);
    setContentView(R.layout.activity_main_screen);

    LoadViewData();

    vp = findViewById(R.id.view_pager);
    Layout_bars = findViewById(R.id.layoutBars);
    txt_login = findViewById(R.id.txt_login);
    signup = findViewById(R.id.signup);
    screens = new int[]{
            R.layout.intro_screen1,
            R.layout.intro_screen2,
            R.layout.intro_screen3,
    };
    myvpAdapter = new MyViewPagerAdapter();
    vp.setAdapter(myvpAdapter);
    preferenceManager = new PreferenceManager(this);
    vp.addOnPageChangeListener(viewPagerPageChangeListener);
    if (!preferenceManager.FirstLaunch()) {
        launchMain();
        finish();
    }
    ColoredBars(0);
}

private void LoadViewData() {
    Call<ViewpagerBean> beanCall = APIClient
            .getapiClient()
            .getapiInterface()
            .getViewPagerResponce();

    beanCall.enqueue(new Callback<ViewpagerBean>() {
        int i;

        @Override
        public void onResponse(Call<ViewpagerBean> call, Response<ViewpagerBean> response) {
            ViewpagerBean viewpagerBean = response.body();


            Log.d(TAG, "onResponse: " + viewpagerBean.getData().size());
            Toast.makeText(MainScreen.this, viewpagerBean.getData().get(i).getHeading(), Toast.LENGTH_SHORT).show();

        }

        @Override
        public void onFailure(Call<ViewpagerBean> call, Throwable t) {
            Log.e(TAG, "Error" + t.getMessage());
            Toast.makeText(MainScreen.this, t.getMessage(), Toast.LENGTH_SHORT).show();
        }
    });
}

public void next(View v) {
    int i = getItem(+1);
    if (i < screens.length) {
        vp.setCurrentItem(i);
    } else {
        launchMain();
    }
}

public void skip(View view) {
    launchMain();
}

private void ColoredBars(int thisScreen) {
    int[] colorsInactive = getResources().getIntArray(R.array.dot_on_page_not_active);
    int[] colorsActive = getResources().getIntArray(R.array.dot_on_page_active);
    bottomBars = new TextView[screens.length];

    Layout_bars.removeAllViews();
    for (int i = 0; i < bottomBars.length; i++) {
        bottomBars[i] = new TextView(this);
        bottomBars[i].setTextSize(100);
        bottomBars[i].setText(Html.fromHtml("&#175"));
        Layout_bars.addView(bottomBars[i]);
        bottomBars[i].setTextColor(colorsInactive[thisScreen]);
        signup.setTextColor(colorsInactive[thisScreen]);

    }
    if (bottomBars.length > 0)
        bottomBars[thisScreen].setTextColor(colorsActive[thisScreen]);
    signup.setTextColor(colorsInactive[thisScreen]);

}

private int getItem(int i) {
    return vp.getCurrentItem() + i;
}

private void launchMain() {
    preferenceManager.setFirstTimeLaunch(false);
    startActivity(new Intent(MainScreen.this, MainActivity.class));
    finish();
}

ViewPager.OnPageChangeListener viewPagerPageChangeListener = new ViewPager.OnPageChangeListener() {

    @Override
    public void onPageSelected(int position) {
        ColoredBars(position);
        if (position == screens.length - 1) {

        } else {

        }
    }

    @Override
    public void onPageScrolled(int arg0, float arg1, int arg2) {

    }

    @Override
    public void onPageScrollStateChanged(int arg0) {

    }
};

public class MyViewPagerAdapter extends PagerAdapter {
    private LayoutInflater inflater;

    public MyViewPagerAdapter() {
    }

    @Override
    public Object instantiateItem(ViewGroup container, int position) {
        inflater = (LayoutInflater) getSystemService(Context.LAYOUT_INFLATER_SERVICE);
        View view = inflater.inflate(screens[position], container, false);
        container.addView(view);
        return view;
    }

    @Override
    public int getCount() {
        return screens.length;
    }

    @Override
    public void destroyItem(ViewGroup container, int position, Object object) {
        View v = (View) object;
        container.removeView(v);

    }

    @Override
    public boolean isViewFromObject(View v, Object object) {
        return v == object;
    }
}