package net.sf.appstatus.services;
   
   public class CallStatistics {
   
   	private Long maxResponseTime;
   	private double avgResponseTime = 0;
   	private long failures = 0;
   	private long errors = 0;
   	private long hits = 0;
  	private Long minResponseTime;
  	private double avgNestedCalls = 0;
  
  	private int minMaxDelay;
  
  	/**
  	 * Because firsts runs are always longer than real times, min and max
  	 * measurements can be delayed until the services is called a few times.
  	 * 
  	 * @param minMaxDelay
  	 *            number of hits before starting to measure min and max times.
  	 */
  	public CallStatistics(int minMaxDelay) {
  		this.minMaxDelay = minMaxDelay;
  	}
  
  	public Long getMaxResponseTime() {
  		return maxResponseTime;
  	}
  
  	public double getAvgResponseTime() {
  		return avgResponseTime;
  	}
  
  	public long getFailures() {
  		return failures;
  	}
  
  	public long getErrors() {
  		return errors;
  	}
  
  	public long getHits() {
  		return hits;
  	}
  
  	public Long getMinResponseTime() {
  		return minResponseTime;
  	}
  
  	/**
  	 * @return the avgNestedCalls
  	 */
  	public double getAvgNestedCalls() {
  		return avgNestedCalls;
  	}
  
  	public void addCall(Long executionTime, boolean failure, boolean error, int nestedCalls) {
  		synchronized (this) {
  			hits++;
  			if (failure) {
  				failures++;
  			}
  
  			if (error) {
  				errors++;
  			}
  
  			if (hits > minMaxDelay) {
  				if (maxResponseTime == null || maxResponseTime < executionTime) {
  					maxResponseTime = executionTime;
  				}
  
  				if (minResponseTime == null || minResponseTime > executionTime) {
  					minResponseTime = executionTime;
  				}
  			}
  
  			avgResponseTime = (avgResponseTime * (hits - 1) + executionTime) / (hits);
  
  			avgNestedCalls = (avgNestedCalls * (hits - 1) + (double) nestedCalls) / hits;
  		}
  
  	}
  }