/*******************************************************************************
 * Copyright 2011 See AUTHORS file.
 * 
 * Licensed under the Apache License, Version 2.0 (the "License");
 * you may not use this file except in compliance with the License.
 * You may obtain a copy of the License at
 * 
 *   http://www.apache.org/licenses/LICENSE-2.0
 * 
 * Unless required by applicable law or agreed to in writing, software
 * distributed under the License is distributed on an "AS IS" BASIS,
 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 * See the License for the specific language governing permissions and
 * limitations under the License.
 ******************************************************************************/

package com.badlogic.gdx.tests;

import com.badlogic.gdx.Gdx;
import com.badlogic.gdx.graphics.Color;
import com.badlogic.gdx.graphics.GL20;
import com.badlogic.gdx.graphics.Pixmap;
import com.badlogic.gdx.graphics.Pixmap.Format;
import com.badlogic.gdx.graphics.Texture;
import com.badlogic.gdx.graphics.g2d.BitmapFont;
import com.badlogic.gdx.graphics.g2d.SpriteBatch;
import com.badlogic.gdx.scenes.scene2d.Actor;
import com.badlogic.gdx.scenes.scene2d.Stage;
import com.badlogic.gdx.scenes.scene2d.ui.Image;
import com.badlogic.gdx.scenes.scene2d.ui.Skin;
import com.badlogic.gdx.scenes.scene2d.ui.Table;
import com.badlogic.gdx.scenes.scene2d.ui.TextButton;
import com.badlogic.gdx.scenes.scene2d.ui.TextButton.TextButtonStyle;
import com.badlogic.gdx.scenes.scene2d.utils.ChangeListener;
import com.badlogic.gdx.tests.utils.GdxTest;

public class UISimpleTest extends GdxTest {
	Skin skin;
	Stage stage;
	SpriteBatch batch;

	@Override
	public void create () {
		batch = new SpriteBatch();
		stage = new Stage();
		Gdx.input.setInputProcessor(stage);

		// A skin can be loaded via JSON or defined programmatically, either is fine. Using a skin is optional but strongly
		// recommended solely for the convenience of getting a texture, region, etc as a drawable, tinted drawable, etc.
		skin = new Skin();

		// Generate a 1x1 white texture and store it in the skin named "white".
		Pixmap pixmap = new Pixmap(1, 1, Format.RGBA8888);
		pixmap.setColor(Color.WHITE);
		pixmap.fill();
		skin.add("white", new Texture(pixmap));

		// Store the default libgdx font under the name "default".
		skin.add("default", new BitmapFont());

		// Configure a TextButtonStyle and name it "default". Skin resources are stored by type, so this doesn't overwrite the font.
		TextButtonStyle textButtonStyle = new TextButtonStyle();
		textButtonStyle.up = skin.newDrawable("white", Color.DARK_GRAY);
		textButtonStyle.down = skin.newDrawable("white", Color.DARK_GRAY);
		textButtonStyle.checked = skin.newDrawable("white", Color.BLUE);
		textButtonStyle.over = skin.newDrawable("white", Color.LIGHT_GRAY);
		textButtonStyle.font = skin.getFont("default");
		skin.add("default", textButtonStyle);

		// Create a table that fills the screen. Everything else will go inside this table.
		Table table = new Table();
		table.setFillParent(true);
		stage.addActor(table);

		// Create a button with the "default" TextButtonStyle. A 3rd parameter can be used to specify a name other than "default".
		final TextButton button = new TextButton("Click me!", skin);
		table.add(button);

		// Add a listener to the button. ChangeListener is fired when the button's checked state changes, eg when clicked,
		// Button#setChecked() is called, via a key press, etc. If the event.cancel() is called, the checked state will be reverted.
		// ClickListener could have been used, but would only fire when clicked. Also, canceling a ClickListener event won't
		// revert the checked state.
		button.addListener(new ChangeListener() {
			public void changed (ChangeEvent event, Actor actor) {
				System.out.println("Clicked! Is checked: " + button.isChecked());
				button.setText("Good job!");
			}
		});

		// Add an image actor. Have to set the size, else it would be the size of the drawable (which is the 1x1 texture).
		table.add(new Image(skin.newDrawable("white", Color.RED))).size(64);
	}

	@Override
	public void render () {
		Gdx.gl.glClearColor(0.2f, 0.2f, 0.2f, 1);
		Gdx.gl.glClear(GL20.GL_COLOR_BUFFER_BIT);
		stage.act(Math.min(Gdx.graphics.getDeltaTime(), 1 / 30f));
		stage.draw();
	}

	@Override
	public void resize (int width, int height) {
		stage.getViewport().update(width, height, true);
	}

	@Override
	public void dispose () {
		stage.dispose();
		skin.dispose();
	}
}