/*
 * SlipBandAreaChart.java
 * Android-Charts
 *
 * Created by limc on 2014.
 *
 * Copyright 2011 limc.cn All rights reserved.
 *
 * 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 net.bither.charts.view;

import java.util.List;

import net.bither.charts.entity.DateValueEntity;
import net.bither.charts.entity.LineEntity;
import android.content.Context;
import android.graphics.Canvas;
import android.graphics.Paint;
import android.graphics.Path;
import android.util.AttributeSet;

/**
 * <p>
 * en
 * </p>
 * <p>
 * jp
 * </p>
 * <p>
 * cn
 * </p>
 * 
 * @author limc
 * @version v1.0 2014/01/22 18:03:26
 * 
 */
public class SlipBandAreaChart extends SlipLineChart {

	/**
	 * <p>
	 * Constructor of SlipBandAreaChart
	 * </p>
	 * <p>
	 * SlipBandChart类对象的构造函数
	 * </p>
	 * <p>
	 * SlipBandChartのコンストラクター
	 * </p>
	 * 
	 * @param context
	 * @param attrs
	 * @param defStyle
	 */
	public SlipBandAreaChart(Context context, AttributeSet attrs, int defStyle) {
		super(context, attrs, defStyle);

	}

	/**
	 * <p>
	 * Constructor of SlipBandAreaChart
	 * </p>
	 * <p>
	 * SlipBandChart类对象的构造函数
	 * </p>
	 * <p>
	 * SlipBandChartのコンストラクター
	 * </p>
	 * 
	 * @param context
	 * @param attrs
	 */
	public SlipBandAreaChart(Context context, AttributeSet attrs) {
		super(context, attrs);

	}

	/**
	 * <p>
	 * Constructor of SlipBandAreaChart
	 * </p>
	 * <p>
	 * SlipBandChart类对象的构造函数
	 * </p>
	 * <p>
	 * SlipBandChartのコンストラクター
	 * </p>
	 * 
	 * @param context
	 */
	public SlipBandAreaChart(Context context) {
		super(context);

	}

	/*
	 * (non-Javadoc)
	 * 
	 * <p>Called when is going to draw this chart<p> <p>チャートを書く前、メソッドを呼ぶ<p>
	 * <p>绘制图表时调用<p>
	 * 
	 * @param canvas
	 * 
	 * @see android.view.View#onDraw(android.graphics.Canvas)
	 */
	@Override
	protected void onDraw(Canvas canvas) {
		super.onDraw(canvas);
		// draw lines
		drawAreas(canvas);
	}

	/**
	 * <p>
	 * draw lines
	 * </p>
	 * <p>
	 * ラインを書く
	 * </p>
	 * <p>
	 * 绘制线条
	 * </p>
	 * 
	 * @param canvas
	 */
	protected void drawAreas(Canvas canvas) {
		if (null == linesData) {
			return;
		}
		if (linesData.size() < 2) {
			return;
		}
		LineEntity<DateValueEntity> line1 = (LineEntity<DateValueEntity>) linesData
				.get(0);
		LineEntity<DateValueEntity> line2 = (LineEntity<DateValueEntity>) linesData
				.get(1);
		List<DateValueEntity> line1Data = line1.getLineData();
		List<DateValueEntity> line2Data = line2.getLineData();

		if (line1.isDisplay() == false || line2.isDisplay() == false) {
			return;
		}
		if (line1Data == null || line2Data == null) {
			return;
		}

		Paint mPaint = new Paint();
		mPaint.setColor(line1.getLineColor());
		mPaint.setAlpha(70);
		mPaint.setAntiAlias(true);

		// distance between two points
		float lineLength = getDataQuadrantPaddingWidth() / displayNumber - 1;
		// start point‘s X
		// set start point’s X
		float startX = getDataQuadrantPaddingStartX() + lineLength / 2f;
		float lastY = 0;
		float lastX = 0;

		Path areaPath = new Path();

		for (int j = displayFrom; j < displayFrom + displayNumber; j++) {
			float value1 = line1Data.get(j).getValue();
			float value2 = line2Data.get(j).getValue();

			// calculate Y
			float valueY1 = (float) ((1f - (value1 - minValue)
					/ (maxValue - minValue)) * getDataQuadrantPaddingHeight())
					+ getDataQuadrantPaddingStartY();
			float valueY2 = (float) ((1f - (value2 - minValue)
					/ (maxValue - minValue)) * getDataQuadrantPaddingHeight())
					+ getDataQuadrantPaddingStartY();

			// 绘制线条路径
			if (j == displayFrom) {
				areaPath.moveTo(startX, valueY1);
				areaPath.lineTo(startX, valueY2);
				areaPath.moveTo(startX, valueY1);
			} else {
				areaPath.lineTo(startX, valueY1);
				areaPath.lineTo(startX, valueY2);
				areaPath.lineTo(lastX, lastY);
				areaPath.close();
				areaPath.moveTo(startX, valueY1);
			}

			lastX = startX;
			lastY = valueY2;
			startX = startX + 1 + lineLength;
		}
		areaPath.close();
		canvas.drawPath(areaPath, mPaint);
	}
}
