/*
 * Copyright (C) 2012. Rayman Zhang <raymanzhang@gmail.com>
 *
 * This program is free software: you can redistribute it and/or modify
 * it under the terms of the GNU General Public License as published by
 * the Free Software Foundation, version 3 of the License.
 *
 * This program is distributed in the hope that it will be useful,
 * but WITHOUT ANY WARRANTY; without even the implied warranty of
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
 * GNU General Public License for more details.
 *
 * You should have received a copy of the GNU General Public License
 * along with this program.  If not, see <http://www.gnu.org/licenses/>.
 */

/**
 *
 */
package cn.mdict.widgets;

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

import android.content.Context;
import android.util.AttributeSet;
import android.view.View;
import android.view.ViewGroup;
import android.widget.Checkable;
import android.widget.RelativeLayout;

/**
 * Extension of a relative layout to provide a checkable behaviour
 *
 * @author marvinlabs
 */
public class CheckableLayout extends RelativeLayout implements
        Checkable {

    private boolean isChecked;
    private List<Checkable> checkableViews;

    public CheckableLayout(Context context, AttributeSet attrs,
                           int defStyle) {
        super(context, attrs, defStyle);
        initialise(attrs);
    }

    public CheckableLayout(Context context, AttributeSet attrs) {
        super(context, attrs);
        initialise(attrs);
    }

    public CheckableLayout(Context context, int checkableId) {
        super(context);
        initialise(null);
    }

    /*
     * @see android.widget.Checkable#isChecked()
     */
    public boolean isChecked() {
        return isChecked;
    }

    /*
     * @see android.widget.Checkable#setChecked(boolean)
     */
    public void setChecked(boolean isChecked) {
        this.isChecked = isChecked;
        for (Checkable c : checkableViews) {
            c.setChecked(isChecked);
        }
    }

    /*
     * @see android.widget.Checkable#toggle()
     */
    public void toggle() {
        this.isChecked = !this.isChecked;
        for (Checkable c : checkableViews) {
            c.toggle();
        }
    }

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

        final int childCount = this.getChildCount();
        for (int i = 0; i < childCount; ++i) {
            findCheckableChildren(this.getChildAt(i));
        }
    }

    /**
     * Read the custom XML attributes
     */
    private void initialise(AttributeSet attrs) {
        this.isChecked = false;
        this.checkableViews = new ArrayList<Checkable>(5);
    }

    /**
     * Add to our checkable list all the children of the view that implement the
     * interface Checkable
     */
    private void findCheckableChildren(View v) {
        if (v instanceof Checkable) {
            this.checkableViews.add((Checkable) v);
        }

        if (v instanceof ViewGroup) {
            final ViewGroup vg = (ViewGroup) v;
            final int childCount = vg.getChildCount();
            for (int i = 0; i < childCount; ++i) {
                findCheckableChildren(vg.getChildAt(i));
            }
        }
    }
}
