package gueei.binding.converters;

import gueei.binding.Binder;
import gueei.binding.Binder.InflateResult;
import gueei.binding.BindingLog;
import gueei.binding.Converter;
import gueei.binding.DynamicObject;
import gueei.binding.IObservable;
import gueei.binding.v30.viewAttributes.adapterView.viewPager.PagerAdapterObservable;
import gueei.binding.viewAttributes.templates.Layout;
import android.view.View;
import android.view.ViewGroup;

/**
 * PAGERADAPTER accepts unlimited number of DynamicObjects
 * It will return a PagerAdapter
 * 
 * @usage params
 * 
 * @arg params DynamicObject
 * 
 * @item template gueei.binding.viewAttributes.templates.Layout
 * @item item Object Item View Model
 * @item @optional width float
 * @item @optional title String
 * 
 * @return android.widget.Adapter
 * 
 * @author andy
 *
 */
public class PAGERITEMS extends Converter<PagerAdapterObservable> {
	public PAGERITEMS(IObservable<?>[] dependents) {
	    super(PagerAdapterObservable.class, dependents);
    }

	@Override
    public PagerAdapterObservable calculateValue(Object... args) throws Exception {
		DynamicObject[] dobjs = new DynamicObject[args.length];
		System.arraycopy(args, 0, dobjs, 0, args.length);
		
		return new ObsPagerAdapter(dobjs);
    }
	
	private static class ObsPagerAdapter extends PagerAdapterObservable{
		@Override
        public CharSequence getPageTitle(int position) {
			return items[position].tryGetObservableValue("title", "");
        }

		private final DynamicObject[] items;
		
		public ObsPagerAdapter(DynamicObject... objs){
			items = objs;
		}
		
		@Override
        public float getPageWidth(int position) {
			return items[position].tryGetObservableValue("width", 1.0f);
        }

		@Override
        public Object instantiateItem(ViewGroup container, int position) {
			// TODO: cache the view, handle the destroy also
			try {
				Layout layout;
	            layout = (Layout)items[position].getObservableByName("template").get();
	            InflateResult result = 
	            		Binder.inflateView(container.getContext(), layout.getDefaultLayoutId(), container, false);
	            View root = 
	            		Binder.bindView(container.getContext(), result, items[position].getObservableByName("item").get());
	            container.addView(root);
	            return root;
            } catch (Exception e) {
	            BindingLog.exception("PAGERADAPTER", e);
	            return null;
            }
        }

		@Override
        public void notifyDataSetChanged() {
	        // TODO Auto-generated method stub
	        super.notifyDataSetChanged();
        }

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

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

		@Override
        public boolean isViewFromObject(View arg0, Object arg1) {
			return arg0.equals(arg1);
        }
	}
}