/**
 * @author vivek
 */
//=========================================================
public class CategoriesSlideView extends LinearLayout implements View.OnTouchListener{

    private final static int Offset = 30, MaxAlpha = 180;
    private float startX = 0;
    private int dwidth = 0;
    private View overlay;

    //=================================
    public CategoriesSlideView(Context context, AttributeSet attrs) {
        super(context, attrs);
    }

    //=================================
    @Override
    public void onAttachedToWindow(){
        super.onAttachedToWindow();
        if(android.os.Build.VERSION.SDK_INT>=android.os.Build.VERSION_CODES.LOLLIPOP)
            setElevation(20f);
        setOnTouchListener(this);
        animate().alpha(0).setDuration(0).start();
        startX = getX();
        postDelayed(new Runnable(){public void run(){

            WindowManager mgr = (WindowManager)getContext().getSystemService(Context.WINDOW_SERVICE);
            DisplayMetrics dm = new DisplayMetrics();
            mgr.getDefaultDisplay().getMetrics(dm);
            dwidth = dm.widthPixels;

            View parent = (View)getParent();
            ValueAnimator anim = ObjectAnimator.ofFloat(CategoriesSlideView.this, "translationX", 0, parent.getX()+parent.getWidth()-Offset);
            anim.setDuration(0);
            anim.start();
        }}, 400);
    }

    //=================================
    private void openIt(){
        animate().alpha(1).setDuration(0).start();
        ValueAnimator anim = ObjectAnimator.ofFloat(CategoriesSlideView.this, "translationX", getX(), dwidth-getWidth());
        anim.setDuration(200);
        anim.start();
    }

    //=================================
    public void openDirect(){
        openIt();
        addOverlay();
        overlay.getBackground().setAlpha(MaxAlpha);
    }

    //=================================
    public void closeDirect(){
        closeIt();
    }

    //=================================
    private void closeIt(){
        ValueAnimator anim = ObjectAnimator.ofFloat(CategoriesSlideView.this, "translationX", getX(), dwidth-Offset);
        anim.setDuration(200);
        anim.start();
        animate().alpha(0).setDuration(300).start();
        overlay.setVisibility(View.GONE);
    }

    //=================================
    private void addOverlay(){
        if(overlay!=null && overlay.getVisibility()==View.VISIBLE) return;
        ViewGroup parent = (ViewGroup)getParent();
        overlay = new View(getContext());
        overlay.setBackgroundColor(Color.BLACK);
        overlay.getBackground().setAlpha(10);
        parent.addView(overlay);
        overlay.setOnClickListener(new View.OnClickListener() {
            public void onClick(View v) {
                closeIt();
            }
        });
        bringToFront();
    }

    //=================================
    @Override
    public boolean onInterceptTouchEvent(MotionEvent event){
        return false;
    }

    //=================================
    @Override
    public boolean onTouch(View v, MotionEvent event) {
        switch(event.getAction()){
            case MotionEvent.ACTION_DOWN:
                addOverlay();
                animate().alpha(1).start();
                break;
            case MotionEvent.ACTION_UP:
                if((dwidth-event.getRawX())>((getWidth()*2)/3)){
                    openIt();
                }else{
                    closeIt();
                }
                break;
            default:
                if((dwidth-event.getRawX())>(startX+getWidth()))
                    return true;
                v.setX(event.getRawX());
                overlay.getBackground().setAlpha((int)((1-(event.getRawX()/dwidth))*MaxAlpha));
                break;
        }
        return true;
    }
}