package org.yeshi.utils.statistic.http;

import java.util.List;

public class LocalhostAccessLogUtil {

	/**
	 * 将单行日志文件解析为对象
	 * 
	 * @param content
	 * @return
	 */
	public static HttpRequestInfo parseTomcatSingleLine(String content) {

		try {
			HttpRequestInfo info = new HttpRequestInfo();
			int start = content.indexOf("\"");
			content = content.substring(start, content.length());
			start = content.indexOf("\"", 1);
			String url = content.substring(1, start);
			info.setMethod(url.split(" ")[0]);
			// 链接
			info.setUrl(url.split(" ")[1].split("\\?")[0]);
			// 时间
			info.setProtocal(url.split(" ")[2]);
			String[] sts = content.substring(start + 1, content.length()).trim().split(" ");
			info.setStateCode(Integer.parseInt(sts[0]));
			info.setTime(sts[1].trim().equalsIgnoreCase("-") ? Integer.MAX_VALUE : Integer.parseInt(sts[1]));
			return info;
		} catch (Exception e) {
		}

		return null;
	}

	/**
	 * 求请求时间的平均值
	 * 
	 * @param list
	 * @return
	 */
	public static int getTimeAvg(List<HttpRequestInfo> list) {
		int count = 0;
		long total = 0;
		for (HttpRequestInfo info : list) {
			// 去除最大数值与最小数值
			if (info.getTime() > 0 && info.getTime() < Integer.MAX_VALUE) {
				total += info.getTime();
				count++;
			}
		}
		if (count <= 0)
			return 0;

		return (int) (total / count);
	}

	/**
	 * 获取方差
	 * 
	 * @param list
	 * @return
	 */
	public static int getVariance(List<HttpRequestInfo> list) {
		int avg = getTimeAvg(list);
		long total = 0;
		for (HttpRequestInfo info : list) {
			total += Math.pow(info.getTime() - avg, 2);
		}
		return (int) (total / list.size());
	}

}